Metabolite fingerprinting of Camptotheca acuminata and the HPLC-ESI-MS/MS analysis of camptothecin and related alkaloids.

PubMed

Montoro, Paola; Maldini, Mariateresa; Piacente, Sonia; Macchia, Mario; Pizza, Cosimo

2010-01-20

The major phytochemical constituents, namely, alkaloids, flavonoids and ellagic acid derivatives, of leaves of Camptotheca acuminata were identified using high performance liquid chromatography (HPLC) coupled with electrospray mass spectrometry (ESI-MS) in extracts of plants cultivated in Italy and collected at different growth stages. Alkaloids related to camptothecin were identified and quantified by HPLC coupled with ESI-tandem mass spectrometry (MS/MS) employing, respectively, an ion trap and a triple quadrupole mass analyser. The fragmentation patterns of alkaloids related to camptothecin were analysed and a specific Multiple Reaction Monitoring HPLC-MS/MS method was developed for the quantitative determination of these constituents. The described method provides high sensitivity and specificity for the characterisation and quantitative determination of the alkaloids in C. acuminata.

HPLC Analysis of Chlorophyll a, Chlorophyll b, and Beta-Carotene in Collard Greens: A Project for a Problem-Oriented Laboratory Course.

ERIC Educational Resources Information Center

Silveira, Augustine, Jr.; And Others

1984-01-01

High performance liquid chromatography (HPLC) is used to separate and quantitate beta-carotene, chlorophyll a, and chlorophyll b originating from collard greens. Experimental procedures used and typical results obtained are discussed. (JN)

A novel approach for quantitation of nonderivatized sialic acid in protein therapeutics using hydrophilic interaction chromatographic separation and nano quantity analyte detection.

PubMed

Chemmalil, Letha; Suravajjala, Sreekanth; See, Kate; Jordan, Eric; Furtado, Marsha; Sun, Chong; Hosselet, Stephen

2015-01-01

This paper describes a novel approach for the quantitation of nonderivatized sialic acid in glycoproteins, separated by hydrophilic interaction chromatography, and detection by Nano Quantity Analyte Detector (NQAD). The detection technique of NQAD is based on measuring change in the size of dry aerosol and converting the particle count rate into chromatographic output signal. NQAD detector is suitable for the detection of sialic acid, which lacks sufficiently active chromophore or fluorophore. The water condensation particle counting technology allows the analyte to be enlarged using water vapor to provide highest sensitivity. Derivatization-free analysis of glycoproteins using HPLC/NQAD method with PolyGLYCOPLEX™ amide column is well correlated with HPLC method with precolumn derivatization using 1, 2-diamino-4, 5-methylenedioxybenzene (DMB) as well as the Dionex-based high-pH anion-exchange chromatography (or ion chromatography) with pulsed amperometric detection (HPAEC-PAD). With the elimination of derivatization step, HPLC/NQAD method is more efficient than HPLC/DMB method. HPLC/NQAD method is more reproducible than HPAEC-PAD method as HPAEC-PAD method suffers high variability because of electrode fouling during analysis. Overall, HPLC/NQAD method offers broad linear dynamic range as well as excellent precision, accuracy, repeatability, reliability, and ease of use, with acceptable comparability to the commonly used HPAEC-PAD and HPLC/DMB methods. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

[The qualitative analysis and quantitative analysis of purification of salvianolic acids by macroreticular resin].

PubMed

Fang, Xin-sheng; Tan, Xiao-mei

2005-09-01

To purify salvianolic acids by macroreticular resin,then mensurate the contents of salvianolic acids and analyse the chromatogram with HPLC. Make salvianolic acids with macroreticular resin; mensurate the content of Salvianolic acids with UV spestrophotometry: the control compound is protocaechuic aldehyde, and the wavelength is 281 nm. Analysis the chromatogram with HPLC, and compare the chromatogram in different technics: zorbax ODS column (4.6 mm x 250 mm, 5 microm), mobilephase: 1% aceticacid-water and methanol in different proportions, the wavelength is 281 nm. The contents of salvianolic acids is 53.8%; HPLC chromatogram indicate that the method is reasonable to make salvianolic acids. Determination of contents and HPLC chromatogram can control the quality of Salvianolic acids more accurately.

Simultaneous HPLC quantitative analysis of active compounds in leaves of Moringa oleifera Lam.

PubMed

Vongsak, Boonyadist; Sithisarn, Pongtip; Gritsanapan, Wandee

2014-08-01

Moringa oleifera Lam. has been used as a traditional medicine for the treatment of numerous diseases. A simultaneous high-performance liquid chromatography (HPLC) analysis was developed and validated for the determination of the contents of crypto-chlorogenic acid, isoquercetin and astragalin, the primary antioxidative compounds, in M. oleifera leaves. HPLC analysis was successfully conducted by using a Hypersil BDS C18 column, eluted with a gradient of methanol-1% acetic acid with a flow rate of 1 mL/min, and detected at 334 nm. Parameters for the validation included linearity, precision, accuracy and limits of detection and quantitation. The developed HPLC method was precise, with relative standard deviation < 2%. The recovery values of crypto-chlorogenic acid, isoquercetin and astragalin in M. oleifera leaf extracts were 98.50, 98.47 and 98.59%, respectively. The average contents of these compounds in the dried ethanolic extracts of the leaves of M. oleifera collected from different regions of Thailand were 0.081, 0.120 and 0.153% (w/w), respectively. The developed HPLC method was appropriate and practical for the simultaneous analysis of crypto-chlorogenic acid, isoquercetin and astragalin in the leaf extract of M. oleifera. This work is valuable as guidance for the standardization of the leaf extracts and pharmaceutical products of M. oleifera. © The Author [2013]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

DETERMINATION OF CHLOROPHEONIS, NITROPHENOIS AND METHYLPHENOIS IN GROUND-WATER SAMPLES USING HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

EPA Science Inventory

A high performance liquid chromatography (HPLC) method was developed to quantitatively determine phenolic compounds and their isomers in aqueous samples. The HPLC method can analyze a mixture of 15 contaminants in the same analytical run with an analysis time of 25 minutes. The...

DETERMINATION OF CHLOROPHENOLS, NITROPHENOLS, AND METHYLPHENOLS IN GROUND-WATER SAMPLES USING HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

EPA Science Inventory

A high performance liquid chromatography (HPLC) method was developed to quantitatively determine phenolic compounds and their isomers in aqueous samples. The HPLC method can analyze a mixture of 15 contaminants in the same analytical run with an analysis time of 25 minutes. The...

Qualitative and quantitative analyses of flavonoids in Spirodela polyrrhiza by high-performance liquid chromatography coupled with mass spectrometry.

PubMed

Qiao, Xue; He, Wen-ni; Xiang, Cheng; Han, Jian; Wu, Li-jun; Guo, De-an; Ye, Min

2011-01-01

Spirodela polyrrhiza (L.) Schleid. is a traditional Chinese herbal medicine for the treatment of influenza. Despite its wide use in Chinese medicine, no report on quality control of this herb is available so far. To establish qualitative and quantitative analytical methods by high-performance liquid chromatography (HPLC) coupled with mass spectrometry (MS) for the quality control of S. polyrrhiza. The methanol extract of S. polyrrhiza was analysed by HPLC/ESI-MS(n). Flavonoids were identified by comparing with reference standards or according to their MS(n) (n = 2-4) fragmentation behaviours. Based on LC/MS data, a standardised HPLC fingerprint was established by analysing 15 batches of commercial herbal samples. Furthermore, quantitative analysis was conducted by determining five major flavonoids, namely luteolin 8-C-glucoside, apigenin 8-C-glucoside, luteolin 7-O-glucoside, apigenin 7-O-glucoside and luteolin. A total of 18 flavonoids were identified by LC/MS, and 14 of them were reported from this herb for the first time. The HPLC fingerprints contained 10 common peaks, and could differentiate good quality batches from counterfeits. The total contents of five major flavonoids in S. polyrrhiza varied significantly from 4.28 to 19.87 mg/g. Qualitative LC/MS and quantitative HPLC analytical methods were established for the comprehensive quality control of S. polyrrhiza. Copyright © 2011 John Wiley & Sons, Ltd.

Simultaneous determination of eight major steroids from Polyporus umbellatus by high-performance liquid chromatography coupled with mass spectrometry detections.

PubMed

Zhao, Ying-yong; Cheng, Xian-long; Zhang, Yongmin; Zhao, Ye; Lin, Rui-chao; Sun, Wen-ji

2010-02-01

Polyporus umbellatus is a widely used diuretic herbal medicine. In this study, a high-performance liquid chromatography coupled with atmospheric pressure chemical ionization-mass spectrometric detection (HPLC-APCI-MS) method was developed for qualitative and quantitative analysis of steroids, as well as for the quality control of Polyporus umbellatus. The selectivity, reproducibility and sensitivity were compared with HPLC with photodiode array detection and evaporative light scattering detection (ELSD). Selective ion monitoring in positive mode was used for qualitative and quantitative analysis of eight major components and beta-ecdysterone was used as the internal standard. Limits of detection and quantification fell in the ranges 7-21 and 18-63 ng/mL for the eight analytes with an injection of 10 microL samples, and all calibration curves showed good linear regression (r(2) > 0.9919) within the test range. The quantitative results demonstrated that samples from different localities showed different qualities. Advantages, in comparison with conventional HPLC-diode array detection and HPLC-ELSD, are that reliable identification of target compounds could be achieved by accurate mass measurements along with characteristic retention time, and the great enhancement in selectivity and sensitivity allows identification and quantification of low levels of constituents in complex Polyporus umbellatus matrixes. (c) 2009 John Wiley & Sons, Ltd.

High pressure liquid chromatographic method for the separation and quantitation of water-soluble radiolabeled benzene metabolites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sabourin, P.J.; Bechtold, W.E.; Henderson, R.F.

1988-05-01

The glucuronide and sulfate conjugates of benzene metabolite as well as muconic acid and pre-phenyl- and phenylmercapturic acids were separated by ion-pairing HPLC. The HPLC method developed was suitable for automated analysis of a large number of tissue or excreta samples. p-Nitrophenyl (/sup 14/C)glucuronide was used as an internal standard for quantitation of these water-soluble metabolites. Quantitation was verified by spiking liver tissue with various amounts of phenylsulfate or glucuronides of phenol, catechol, or hydroquinone and analyzing by HPLC. Values determined by HPLC analysis were within 10% of the actual amount with which the liver was spiked. The amount ofmore » metabolite present in urine following exposure to (/sup 3/H)benzene was determined using p-nitrophenyl (/sup 14/C)glucuronide as an internal standard. Phenylsulfate was the major water-soluble metabolite in the urine of F344 rats exposed to 50 ppm (/sup 3/H)benzene for 6 h. Muconic acid and an unknown metabolite which decomposed in acidic media to phenylmercapturic acid were also present. Liver, however, contained a different metabolic profile. This indicates that urinary metabolite profiles may not be a true reflection of what is seen in individual tissues.« less

Geographical classification of Epimedium based on HPLC fingerprint analysis combined with multi-ingredients quantitative analysis.

PubMed

Xu, Ning; Zhou, Guofu; Li, Xiaojuan; Lu, Heng; Meng, Fanyun; Zhai, Huaqiang

2017-05-01

A reliable and comprehensive method for identifying the origin and assessing the quality of Epimedium has been developed. The method is based on analysis of HPLC fingerprints, combined with similarity analysis, hierarchical cluster analysis (HCA), principal component analysis (PCA) and multi-ingredient quantitative analysis. Nineteen batches of Epimedium, collected from different areas in the western regions of China, were used to establish the fingerprints and 18 peaks were selected for the analysis. Similarity analysis, HCA and PCA all classified the 19 areas into three groups. Simultaneous quantification of the five major bioactive ingredients in the Epimedium samples was also carried out to confirm the consistency of the quality tests. These methods were successfully used to identify the geographical origin of the Epimedium samples and to evaluate their quality. Copyright © 2016 John Wiley & Sons, Ltd.

Analysis of biodiesel by high performance liquid chromatography using refractive index detector.

PubMed

Syed, Mahin Basha

2017-01-01

High-performance liquid chromatography (HPLC) was used for the determination of compounds occurring during the production of biodiesel from karanja and jatropha oil. Methanol was used for fast monitoring of conversion of karanja and jatropha oil triacylglycerols to fatty acid methyl esters and for quantitation of residual triacylglycerols (TGs), in the final biodiesel product. The individual sample compounds were identified using HPLC. Analysis of fatty acid methyl esters (FAMES) in blends of biodiesel by HPLC using a refractive index and a UV detector at 238 nm. Individual triacylglycerols, diacylglycerols, monoacylglycerols and methyl esters of oleic, linoleic and linolenic acids and free fatty acids were separated within 40 min. Hence HPLC was found to be best for the analysis of biodiesel. Analysis of biodiesel by HPLC using RID detector. Estimation of amount of FAMES in biodiesel. Individual triacylglycerols, diacylglycerols, monoacylglycerols and methyl esters of oleic, linoleic and linolenic acids and free fatty acids were separated within 40 min.

Comparison of high-performance liquid chromatography/tandem mass spectrometry and high-performance liquid chromatography/photo-diode array detection for the quantitation of carotenoids, retinyl esters, α-tocopherol and phylloquinone in chylomicron-rich fractions of human plasma.

PubMed

Kopec, Rachel E; Schweiggert, Ralf M; Riedl, Ken M; Carle, Reinhold; Schwartz, Steven J

2013-06-30

Bioavailability of essential lipophilic micronutrients and carotenoids is of utmost interest for human health, as the consumption of these compounds may help alleviate major nutritional deficiencies, cardiovascular disease, and cancer. High-performance liquid chromatography/photo-diode array detection (HPLC-PDA) and high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) were compared for the quantitative analysis of α- and β-carotene, β-cryptoxanthin, lutein, lycopene, α-tocopherol, phylloquinone, and several retinyl esters from chylomicron-containing triglyceride rich lipoprotein (TRL) fractions of human plasma obtained from two clinical trials. After selecting an efficient extraction method for the analytes, both the HPLC/PDA and the HPLC/MS/MS methods were developed and several parameters validated using an HP 1200 series HPLC system interfaced with a HP 1200 series diode-array detector (Agilent Technologies, Santa Clara, CA, USA) and a QTRAP 5500 (AB Sciex, Foster City, CA, USA) via an atmospheric pressure chemical ionization (APCI) probe operated in positive ion mode. For lycopene, α- and β-carotene, HPLC/MS/MS was up to 37 times more sensitive than HPLC-PDA. PDA detection was shown to be up to 8 times more sensitive for lutein. MS/MS signals were enhanced by matrix components for lutein and β-cryptoxanthin, as determined by referencing to the matrix-independent PDA signal. In contrast, matrix suppression was observed for retinyl palmitate, α-carotene, and β-carotene. Both detectors showed similar suitability for α-tocopherol, lycopene and retinyl palmitate (representing ~73% of total retinyl esters). MS/MS exclusively allowed the quantitation of minor retinyl esters, phylloquinone, and (Z)-lycopene isomers. HPLC/MS/MS was more sensitive than HPLC-PDA for six of the eight analytes and represents a powerful tool for the analysis of chylomicron samples and potentially other biological samples of limited sample size. When internal standards are available for the target carotenoid, employing MS/MS detection may reduce the necessary blood sample volume, which is particularly advantageous for minimizing risk and discomfort to human subjects during clinical studies. Copyright © 2013 John Wiley & Sons, Ltd.

Comparison of high-performance liquid chromatography/tandem mass spectrometry and high-performance liquid chromatography/photo-diode array detection for the quantitation of carotenoids, retinyl esters, α-tocopherol and phylloquinone in chylomicron-rich fractions of human plasma

PubMed Central

Kopec, Rachel E.; Schweiggert, Ralf M.; Riedl, Ken M.; Carle, Reinhold; Schwartz, Steven J.

2013-01-01

Rationale Bioavailability of essential lipophilic micronutrients and carotenoids is of utmost interest for human health, as the consumption of these compounds may help alleviate major nutritional deficiencies, cardiovascular disease, and cancer. High-performance liquid chromatography/photo-diode array detection (HPLC-PDA) and high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) were compared for the quantitative analysis of α- and β-carotene, β-cryptoxanthin, lutein, lycopene, α-tocopherol, phylloquinone, and several retinyl esters from chylomicron-containing triglyceride rich lipoprotein (TRL) fractions of human plasma obtained from two clinical trials. Methods After selecting an efficient extraction method for the analytes, both the HPLC/PDA and the HPLC/MS/MS methods were developed and several parameters validated using an HP 1200 series HPLC system interfaced with a HP 1200 series diode-array detector (Agilent Technologies, Santa Clara, CA, USA) and a QTRAP 5500 (AB Sciex, Foster City, CA, USA) via an atmospheric pressure chemical ionization (APCI) probe operated in positive ion mode. Results For lycopene, α- and β-carotene, HPLC/MS/MS was up to 37 times more sensitive than HPLC-PDA. PDA detection was shown to be up to 8 times more sensitive for lutein. MS/MS signals were enhanced by matrix components for lutein and β-cryptoxanthin, as determined by referencing to the matrix-independent PDA signal. In contrast, matrix suppression was observed for retinyl palmitate, α-carotene, and β-carotene. Both detectors showed similar suitability for α-tocopherol, lycopene and retinyl palmitate (representing ~73% of total retinyl esters). MS/MS exclusively allowed the quantitation of minor retinyl esters, phylloquinone, and (Z)-lycopene isomers. Conclusions HPLC/MS/MS was more sensitive than HPLC-PDA for six of the eight analytes and represents a powerful tool for the analysis of chylomicron samples and potentially other biological samples of limited sample size. When internal standards are available for the target carotenoid, employing MS/MS detection may reduce the necessary blood sample volume, which is particularly advantageous for minimizing risk and discomfort to human subjects during clinical studies. PMID:23681818

High performance liquid chromatography used for quality control of Achyranthis Radix.

PubMed

Zhao, Bing Tian; Jeong, Su Yang; Moon, Dong Cheul; Son, Kun Ho; Son, Jong Keun; Woo, Mi Hee

2012-08-01

To establish a standard of quality control and to identify reliable Achyranthis Radix, three phytoecdysones including ecdysterone (1), 25R-inokosterone (2) and 25S-inokosterone (3) were determined by quantitative HPLC/UV analysis. Three phytoecdysones were separated with an YMC J'sphere ODS C(18) column (250 mm × 4.6 mm, 4 μm) by isocratic elution using 0.1% formic acid in water and acetonitrile (85:15, v/v%) as the mobile phase. The flow rate was 1.0 mL/min and the UV detector wavelength was set at 245 nm. The standards were quantified by HPLC/UV from Achyranthes bidentata Blume and Achyranthes japonica Nakai, as well as Cyathula capitata Moq. and Cyathula officinalis Kuan, which are of a different genus but are comparative herbs. The method was successfully used in the analysis of Achyranthis Radix of different geographical origin or genera with relatively simple conditions and procedures, and the assay results were satisfactory for linearity, recovery, precision, accuracy, stability and robustness. The HPLC analytical method for pattern recognition analysis was validated by repeated analysis of eighteen A. bidentata Blume samples and ten A. japonica Nakai samples. The results indicate that the established HPLC/UV method is suitable for quantitation and pattern recognition analyses for quality evaluation of Achyranthis Radix.

A convenient method for the quantitative determination of elemental sulfur in coal by HPLC analysis of perchloroethylene extracts

USGS Publications Warehouse

Buchanan, D.H.; Coombs, K.J.; Murphy, P.M.; Chaven, C.

1993-01-01

A convenient method for the quantitative determination of elemental sulfur in coal is described. Elemental sulfur is extracted from the coal with hot perchloroethylene (PCE) (tetrachloroethene, C2Cl4) and quantitatively determined by HPLC analysis on a C18 reverse-phase column using UV detection. Calibration solutions were prepared from sublimed sulfur. Results of quantitative HPLC analyses agreed with those of a chemical/spectroscopic analysis. The HPLC method was found to be linear over the concentration range of 6 ?? 10-4 to 2 ?? 10-2 g/L. The lower detection limit was 4 ?? 10-4 g/L, which for a coal sample of 20 g is equivalent to 0.0006% by weight of coal. Since elemental sulfur is known to react slowly with hydrocarbons at the temperature of boiling PCE, standard solutions of sulfur in PCE were heated with coals from the Argonne Premium Coal Sample program. Pseudo-first-order uptake of sulfur by the coals was observed over several weeks of heating. For the Illinois No. 6 premium coal, the rate constant for sulfur uptake was 9.7 ?? 10-7 s-1, too small for retrograde reactions between solubilized sulfur and coal to cause a significant loss in elemental sulfur isolated during the analytical extraction. No elemental sulfur was produced when the following pure compounds were heated to reflux in PCE for up to 1 week: benzyl sulfide, octyl sulfide, thiane, thiophene, benzothiophene, dibenzothiophene, sulfuric acid, or ferrous sulfate. A sluury of mineral pyrite in PCE contained elemental sulfur which increased in concentration with heating time. ?? 1993 American Chemical Society.

Analysis of anthocyanins in commercial fruit juices by using nano-liquid chromatography-electrospray-mass spectrometry and high-performance liquid chromatography with UV-vis detector.

PubMed

Fanali, Chiara; Dugo, Laura; D'Orazio, Giovanni; Lirangi, Melania; Dachà, Marina; Dugo, Paola; Mondello, Luigi

2011-01-01

Nano-LC and conventional HPLC techniques were applied for the analysis of anthocyanins present in commercial fruit juices using a capillary column of 100 μm id and a 2.1 mm id narrow-bore C(18) column. Analytes were detected by UV-Vis at 518 nm and ESI-ion trap MS with HPLC and nano-LC, respectively. Commercial blueberry juice (14 anthocyanins detected) was used to optimize chromatographic separation of analytes and other analysis parameters. Qualitative identification of anthocyanins was performed by comparing the recorded mass spectral data with those of published papers. The use of the same mobile phase composition in both techniques revealed that the miniaturized method exhibited shorter analysis time and higher sensitivity than narrow-bore chromatography. Good intra-day and day-to-day precision of retention time was obtained in both methods with values of RSD less than 3.4 and 0.8% for nano-LC and HPLC, respectively. Quantitative analysis was performed by external standard curve calibration of cyanidin-3-O-glucoside standard. Calibration curves were linear in the concentration ranges studied, 0.1-50 and 6-50 μg/mL for HPLC-UV/Vis and nano-LC-MS, respectively. LOD and LOQ values were good for both methods. In addition to commercial blueberry juice, qualitative and quantitative analysis of other juices (e.g. raspberry, sweet cherry and pomegranate) was performed. The optimized nano-LC-MS method allowed an easy and selective identification and quantification of anthocyanins in commercial fruit juices; it offered good results, shorter analysis time and reduced mobile phase volume with respect to narrow-bore HPLC. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Analysis of limette and bergamot distilled essential oils by HPLC.

PubMed

Buiarelli, Francesca; Cartoni, Giampaolo; Coccioli, Franco; Jasionowska, Renata; Mazzarino, Monica

2002-04-01

This work examines the distilled essential oils of limette and bergamot in order to assess the presence of low volatile substances such as coumarins (bergapten) which, being toxic, must be eliminated before using these oils in the food industry. The quantitative determination of coumarins was carried out by spectrofluorimetric detection. The substances present in the chromatograms, obtained by HPLC with UV detection at 254 nm, were then identified. Moreover, a new coumarin that is present in small quantities was identified using HPLC-MS.

Optimization of Robust HPLC Method for Quantitation of Ambroxol Hydrochloride and Roxithromycin Using a DoE Approach.

PubMed

Patel, Rashmin B; Patel, Nilay M; Patel, Mrunali R; Solanki, Ajay B

2017-03-01

The aim of this work was to develop and optimize a robust HPLC method for the separation and quantitation of ambroxol hydrochloride and roxithromycin utilizing Design of Experiment (DoE) approach. The Plackett-Burman design was used to assess the impact of independent variables (concentration of organic phase, mobile phase pH, flow rate and column temperature) on peak resolution, USP tailing and number of plates. A central composite design was utilized to evaluate the main, interaction, and quadratic effects of independent variables on the selected dependent variables. The optimized HPLC method was validated based on ICH Q2R1 guideline and was used to separate and quantify ambroxol hydrochloride and roxithromycin in tablet formulations. The findings showed that DoE approach could be effectively applied to optimize a robust HPLC method for quantification of ambroxol hydrochloride and roxithromycin in tablet formulations. Statistical comparison between results of proposed and reported HPLC method revealed no significant difference; indicating the ability of proposed HPLC method for analysis of ambroxol hydrochloride and roxithromycin in pharmaceutical formulations. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

High performance liquid chromatographic assay for the quantitation of total glutathione in plasma

NASA Technical Reports Server (NTRS)

Abukhalaf, Imad K.; Silvestrov, Natalia A.; Menter, Julian M.; von Deutsch, Daniel A.; Bayorh, Mohamed A.; Socci, Robin R.; Ganafa, Agaba A.

2002-01-01

A simple and widely used homocysteine HPLC procedure was applied for the HPLC identification and quantitation of glutathione in plasma. The method, which utilizes SBDF as a derivatizing agent utilizes only 50 microl of sample volume. Linear quantitative response curve was generated for glutathione over a concentration range of 0.3125-62.50 micromol/l. Linear regression analysis of the standard curve exhibited correlation coefficient of 0.999. Limit of detection (LOD) and limit of quantitation (LOQ) values were 5.0 and 15 pmol, respectively. Glutathione recovery using this method was nearly complete (above 96%). Intra-assay and inter-assay precision studies reflected a high level of reliability and reproducibility of the method. The applicability of the method for the quantitation of glutathione was demonstrated successfully using human and rat plasma samples.

Quantitation of repaglinide and metabolites in mouse whole-body thin tissue sections using droplet-based liquid microjunction surface sampling-high-performance liquid chromatography-electrospray ionization tandem mass spectrometry.

PubMed

Chen, Weiqi; Wang, Lifei; Van Berkel, Gary J; Kertesz, Vilmos; Gan, Jinping

2016-03-25

Herein, quantitation aspects of a fully automated autosampler/HPLC-MS/MS system applied for unattended droplet-based surface sampling of repaglinide dosed thin tissue sections with subsequent HPLC separation and mass spectrometric analysis of parent drug and various drug metabolites were studied. Major organs (brain, lung, liver, kidney and muscle) from whole-body thin tissue sections and corresponding organ homogenates prepared from repaglinide dosed mice were sampled by surface sampling and by bulk extraction, respectively, and analyzed by HPLC-MS/MS. A semi-quantitative agreement between data obtained by surface sampling and that by employing organ homogenate extraction was observed. Drug concentrations obtained by the two methods followed the same patterns for post-dose time points (0.25, 0.5, 1 and 2 h). Drug amounts determined in the specific tissues was typically higher when analyzing extracts from the organ homogenates. In addition, relative comparison of the levels of individual metabolites between the two analytical methods also revealed good semi-quantitative agreement. Copyright © 2015 Elsevier B.V. All rights reserved.

Quantitation of repaglinide and metabolites in mouse whole-body thin tissue sections using droplet-based liquid microjunction surface sampling-high-performance liquid chromatography-electrospray ionization tandem mass spectrometry

DOE PAGES

Chen, Weiqi; Wang, Lifei; Van Berkel, Gary J.; ...

2015-11-03

Herein, quantitation aspects of a fully automated autosampler/HPLC-MS/MS system applied for unattended droplet-based surface sampling of repaglinide dosed thin tissue sections with subsequent HPLC separation and mass spectrometric analysis of parent drug and various drug metabolites was studied. Major organs (brain, lung, liver, kidney, muscle) from whole-body thin tissue sections and corresponding organ homogenates prepared from repaglinide dosed mice were sampled by surface sampling and by bulk extraction, respectively, and analyzed by HPLC-MS/MS. A semi-quantitative agreement between data obtained by surface sampling and that by employing organ homogenate extraction was observed. Drug concentrations obtained by the two methods followed themore » same patterns for post-dose time points (0.25, 0.5, 1 and 2 h). Drug amounts determined in the specific tissues was typically higher when analyzing extracts from the organ homogenates. Furthermore, relative comparison of the levels of individual metabolites between the two analytical methods also revealed good semi-quantitative agreement.« less

Quantitation of repaglinide and metabolites in mouse whole-body thin tissue sections using droplet-based liquid microjunction surface sampling-high-performance liquid chromatography-electrospray ionization tandem mass spectrometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Weiqi; Wang, Lifei; Van Berkel, Gary J.

Herein, quantitation aspects of a fully automated autosampler/HPLC-MS/MS system applied for unattended droplet-based surface sampling of repaglinide dosed thin tissue sections with subsequent HPLC separation and mass spectrometric analysis of parent drug and various drug metabolites was studied. Major organs (brain, lung, liver, kidney, muscle) from whole-body thin tissue sections and corresponding organ homogenates prepared from repaglinide dosed mice were sampled by surface sampling and by bulk extraction, respectively, and analyzed by HPLC-MS/MS. A semi-quantitative agreement between data obtained by surface sampling and that by employing organ homogenate extraction was observed. Drug concentrations obtained by the two methods followed themore » same patterns for post-dose time points (0.25, 0.5, 1 and 2 h). Drug amounts determined in the specific tissues was typically higher when analyzing extracts from the organ homogenates. Furthermore, relative comparison of the levels of individual metabolites between the two analytical methods also revealed good semi-quantitative agreement.« less

High-Performance Liquid Chromatography (HPLC)-Based Detection and Quantitation of Cellular c-di-GMP.

PubMed

Petrova, Olga E; Sauer, Karin

2017-01-01

The modulation of c-di-GMP levels plays a vital role in the regulation of various processes in a wide array of bacterial species. Thus, investigation of c-di-GMP regulation requires reliable methods for the assessment of c-di-GMP levels and turnover. Reversed-phase high-performance liquid chromatography (RP-HPLC) analysis has become a commonly used approach to accomplish these goals. The following describes the extraction and HPLC-based detection and quantification of c-di-GMP from Pseudomonas aeruginosa samples, a procedure that is amenable to modifications for the analysis of c-di-GMP in other bacterial species.

Quantitative HPLC Analysis of Rosmarinic Acid in Extracts of "Melissa officinalis" and Spectrophotometric Measurement of Their Antioxidant Activities

ERIC Educational Resources Information Center

Canelas, Vera; da Costa, Cristina Teixeira

2007-01-01

The students prepare tea samples using different quantities of lemon balm leaves ("Melissa officinalis") and measure the rosmarinic acid contents by an HPLC-DAD method. The antioxidant properties of the tea samples are evaluated by a spectrophotometric method using a radical-scavenging assay with DPPH. (2,2-diphenyl-1-picrylhydrazyl). Finally the…

HPLC analysis and standardization of Brahmi vati - An Ayurvedic poly-herbal formulation.

PubMed

Mishra, Amrita; Mishra, Arun K; Tiwari, Om Prakash; Jha, Shivesh

2013-09-01

The aim of the present study was to standardize Brahmi vati (BV) by simultaneous quantitative estimation of Bacoside A3 and Piperine adopting HPLC-UV method. BV very important Ayurvedic polyherbo formulation used to treat epilepsy and mental disorders containing thirty eight ingredients including Bacopa monnieri L. and Piper longum L. An HPLC-UV method was developed for the standardization of BV in light of simultaneous quantitative estimation of Bacoside A3 and Piperine, the major constituents of B. monnieri L. and P. longum L. respectively. The developed method was validated on parameters including linearity, precision, accuracy and robustness. The HPLC analysis showed significant increase in amount of Bacoside A3 and Piperine in the in-house sample of BV when compared with all three different marketed samples of the same. Results showed variations in the amount of Bacoside A3 and Piperine in different samples which indicate non-uniformity in their quality which will lead to difference in their therapeutic effects. The outcome of the present investigation underlines the importance of standardization of Ayurvedic formulations. The developed method may be further used to standardize other samples of BV or other formulations containing Bacoside A3 and Piperine.

Development of high performance liquid chromatography method for miconazole analysis in powder sample

NASA Astrophysics Data System (ADS)

Hermawan, D.; Suwandri; Sulaeman, U.; Istiqomah, A.; Aboul-Enein, H. Y.

2017-02-01

A simple high performance liquid chromatography (HPLC) method has been developed in this study for the analysis of miconazole, an antifungal drug, in powder sample. The optimized HPLC system using C8 column was achieved using mobile phase composition containing methanol:water (85:15, v/v), a flow rate of 0.8 mL/min, and UV detection at 220 nm. The calibration graph was linear in the range from 10 to 50 mg/L with r 2 of 0.9983. The limit of detection (LOD) and limit of quantitation (LOQ) obtained were 2.24 mg/L and 7.47 mg/L, respectively. The present HPLC method is applicable for the determination of miconazole in the powder sample with a recovery of 101.28 % (RSD = 0.96%, n = 3). The developed HPLC method provides short analysis time, high reproducibility and high sensitivity.

Development of a Thiolysis HPLC Method for the Analysis of Procyanidins in Cranberry Products.

PubMed

Gao, Chi; Cunningham, David G; Liu, Haiyan; Khoo, Christina; Gu, Liwei

2018-03-07

The objective of this study was to develop a thiolysis HPLC method to quantify total procyanidins, the ratio of A-type linkages, and A-type procyanidin equivalents in cranberry products. Cysteamine was utilized as a low-odor substitute of toluene-α-thiol for thiolysis depolymerization. A reaction temperature of 70 °C and reaction time of 20 min, in 0.3 M of HCl, were determined to be optimum depolymerization conditions. Thiolytic products of cranberry procyanidins were separated by RP-HPLC and identified using high-resolution mass spectrometry. Standards curves of good linearity were obtained on thiolyzed procyanidin dimer A2 and B2 external standards. The detection and quantification limits, recovery, and precision of this method were validated. The new method was applied to quantitate total procyanidins, average degree of polymerization, ratio of A-type linkages, and A-type procyanidin equivalents in cranberry products. Results showed that the method was suitable for quantitative and qualitative analysis of procyanidins in cranberry products.

Assay of flavonoid aglycones from the species of genus Sideritis (Lamiaceae) from Macedonia with HPLC-UV DAD.

PubMed

Janeska, Bisera; Stefova, Marina; Alipieva, Kalina

2007-09-01

Flavonoids obtained from Sideritis species (Lamiaceae), S. raeseri and S. scardica, grown in Macedonia were studied. Qualitative and quantitative analyses of the flavonoid aglycones were performed using high-performance liquid chromatography (HPLC) with a UV diode array detector. Extracts were prepared by acid hydrolysis in acetone, re-extraction in ethyl acetate and evaporation to dryness; the residue dissolved in methanol was subjected to HPLC analysis.Isoscutellarein, chryseriol and apigenin were identified in the extracts. Also, a 4'-methyl ether derivative of isoscutellarein was found, together with hypolaetin and its methyl ether derivative, which were identified according to previously isolated glycosides and literature data. Quantitation was performed using calibration with apigenin.According to this screening analysis, the samples of the genus Sideritis from Macedonia are rich in polyhydroxy flavones and analogous with the previously studied Mediterranean Sideritis species from the Ibero-North African and Greek Sideritis species with respect to the presence of 8-OH flavones and their derivatives.

Quantitative Determination of Fluorinated Caffeic Acid Phenethyl Ester Derivative From Rat Blood Plasma by Liquid Chromatography-Electrospray Ionization Tandem Mass Spectrometry

DTIC Science & Technology

2008-03-06

Caffeic acid phenethyl ester (CAPE), a plant-derived polyphenolic compound (Fig. 1), is a component of bee propolis . Propolis has been used as a folk...analytical methods have been documented. These include an HPLC-UV determination of CAPE from a propolis -containing gel [13], HPLC-ESI-MS measurement...of CAPE from crude propolis [14], and HPLC- ESI-MS/MS analysis of CAPE in biological samples [15]. In this paper, we developed a method using ultra

Development and validation of an RP-HPLC method for quantitative determination of vanillin and related phenolic compounds in Vanilla planifolia.

PubMed

Sinha, Arun Kumar; Verma, Subash Chandra; Sharma, Upendra Kumar

2007-01-01

A simple and fast method was developed using RP-HPLC for separation and quantitative determination of vanillin and related phenolic compounds in ethanolic extract of pods of Vanilla planifolia. Ten phenolic compounds, namely 4-hydroxybenzyl alcohol, vanillyl alcohol, 3,4-dihydroxybenzaldehyde, 4-hydroxybenzoic acid, vanillic acid, 4-hydroxybenzaldehyde, vanillin, p-coumaric acid, ferulic acid, and piperonal were quantitatively determined using ACN, methanol, and 0.2% acetic acid in water as a mobile phase with a gradient elution mode. The method showed good linearity, high precision, and good recovery of compounds of interest. The present method would be useful for analytical research and for routine analysis of vanilla extracts for their quality control.

Qualitative and quantitative determination of yohimbine in authentic yohimbe bark and in commercial aphrodisiacs by HPLC-UV-API/ MS methods.

PubMed

Zanolari, Boris; Ndjoko, Karine; Ioset, Jean-Robert; Marston, Andrew; Hostettmann, Kurt

2003-01-01

The development and validation of a rapid qualitative and quantitative method based on an HPLC-UV-MS technique with atmospheric pressure chemical ionisation and electrospray ionisation for the analysis of yohimbine in a number of commercial aphrodisiac products is reported. HPLC with multiple-stage mass spectrometry experiments allowed the identification of the target compound and increased the selectivity of complex analyses such as those involved with multi-botanical preparations. The precision and the robustness of the method were improved by the use of two internal standards: codeine for UV detection and deuterium-labelled yohimbine for MS detection. Twenty commercial aphrodisiac preparations were analysed and the amount of yohimbine measured and expressed as the maximal dose per day suggested on product labels ranged from 1.32 to 23.16 mg.

Comparison of the phenolic composition of fruit juices by single step gradient HPLC analysis of multiple components versus multiple chromatographic runs optimised for individual families.

PubMed

Bremner, P D; Blacklock, C J; Paganga, G; Mullen, W; Rice-Evans, C A; Crozier, A

2000-06-01

After minimal sample preparation, two different HPLC methodologies, one based on a single gradient reversed-phase HPLC step, the other on multiple HPLC runs each optimised for specific components, were used to investigate the composition of flavonoids and phenolic acids in apple and tomato juices. The principal components in apple juice were identified as chlorogenic acid, phloridzin, caffeic acid and p-coumaric acid. Tomato juice was found to contain chlorogenic acid, caffeic acid, p-coumaric acid, naringenin and rutin. The quantitative estimates of the levels of these compounds, obtained with the two HPLC procedures, were very similar, demonstrating that either method can be used to analyse accurately the phenolic components of apple and tomato juices. Chlorogenic acid in tomato juice was the only component not fully resolved in the single run study and the multiple run analysis prior to enzyme treatment. The single run system of analysis is recommended for the initial investigation of plant phenolics and the multiple run approach for analyses where chromatographic resolution requires improvement.

Development and validation of a reversed-phase fluorescence HPLC method for determination of bucillamine in human plasma using pre-column derivatization with monobromobimane.

PubMed

Lee, Kang Choon; Chun, Young Goo; Kim, Insoo; Shin, Beom Soo; Park, Eun-Seok; Yoo, Sun Dong; Youn, Yu Seok

2009-07-15

A simple, specific and sensitive derivatization with monobromobimane (mBrB) and the corresponding HPLC-fluorescence quantitation method for the analysis of bucillamine in human plasma was developed and validated. The analytical procedure involves a simple protein precipitation, pre-column fluorescence derivatization, and separation by reversed-phase high performance liquid chromatography (RP-HPLC). The calibration curve showed good linearity over a wide concentration range (50 ng/mL to 10 microg/mL) in human plasma (r(2)=0.9998). The lower limit of quantitation (LLOQ) was 50 ng/mL. The average precision and accuracy at LLOQ were within 6.3% and 107.6%, respectively. This method was successfully applied to a pharmacokinetic study after oral administration of a dose (300 mg) of bucillamine to 20 healthy Korean volunteers.

Determination of isoxaflutole (balance) and its metabolites in water using solid phase extraction followed by high-performance liquid chromatography with ultraviolet or mass spectrometry

USGS Publications Warehouse

Lin, Chung-Ho; Lerch, Robert N.; Thurman, E. Michael; Garrett , Harold E.; George, Milon F.

2002-01-01

Balance (isoxaflutole, IXF) belongs to a new family of herbicides referred to as isoxazoles. IXF has a very short soil half-life (<24 h), degrading to a biologically active diketonitrile (DKN) metabolite that is more polar and considerably more stable. Further degradation of the DKN metabolite produces a nonbiologically active benzoic acid (BA) metabolite. Analytical methods using solid phase extraction followed by high-performance liquid chromatography−UV (HPLC-UV) or high-performance liquid chromatography−mass spectrometry (HPLC-MS) were developed for the analysis of IXF and its metabolites in distilled deionized water and ground water samples. To successfully detect and quantify the BA metabolite by HPLC-UV from ground water samples, a sequential elution scheme was necessary. Using HPLC-UV, the mean recoveries from sequential elution of the parent and its two metabolites from fortified ground water samples ranged from 68.6 to 101.4%. For HPLC-MS, solid phase extraction of ground water samples was performed using a polystyrene divinylbenzene polymer resin. The mean HPLC-MS recoveries of the three compounds from ground water samples spiked at 0.05−2 μg/L ranged from 100.9 to 110.3%. The limits of quantitation for HPLC-UV are approximately 150 ng/L for IXF, 100 ng/L for DKN, and 250 ng/L for BA. The limit of quantitation by HPLC-MS is 50 ng/L for each compound. The methods developed in this work can be applied to determine the transport and fate of Balance in the environment.

Determination of isoxaflutole (balance) and its metabolites in water using solid phase extraction followed by high-performance liquid chromatography with ultraviolet or mass spectrometry.

PubMed

Lin, Chung-Ho; Lerch, Robert N; Thurman, E Michael; Garrett, Harold E; George, Milon F

2002-10-09

Balance (isoxaflutole, IXF) belongs to a new family of herbicides referred to as isoxazoles. IXF has a very short soil half-life (<24 h), degrading to a biologically active diketonitrile (DKN) metabolite that is more polar and considerably more stable. Further degradation of the DKN metabolite produces a nonbiologically active benzoic acid (BA) metabolite. Analytical methods using solid phase extraction followed by high-performance liquid chromatography-UV (HPLC-UV) or high-performance liquid chromatography-mass spectrometry (HPLC-MS) were developed for the analysis of IXF and its metabolites in distilled deionized water and ground water samples. To successfully detect and quantify the BA metabolite by HPLC-UV from ground water samples, a sequential elution scheme was necessary. Using HPLC-UV, the mean recoveries from sequential elution of the parent and its two metabolites from fortified ground water samples ranged from 68.6 to 101.4%. For HPLC-MS, solid phase extraction of ground water samples was performed using a polystyrene divinylbenzene polymer resin. The mean HPLC-MS recoveries of the three compounds from ground water samples spiked at 0.05-2 microg/L ranged from 100.9 to 110.3%. The limits of quantitation for HPLC-UV are approximately 150 ng/L for IXF, 100 ng/L for DKN, and 250 ng/L for BA. The limit of quantitation by HPLC-MS is 50 ng/L for each compound. The methods developed in this work can be applied to determine the transport and fate of Balance in the environment.

Development and Validation of an HPLC Method for Karanjin in Pongamia pinnata linn. Leaves.

PubMed

Katekhaye, S; Kale, M S; Laddha, K S

2012-01-01

A rapid, simple and specific reversed-phase HPLC method has been developed for analysis of karanjin in Pongamia pinnata Linn. leaves. HPLC analysis was performed on a C(18) column using an 85:13.5:1.5 (v/v) mixtures of methanol, water and acetic acid as isocratic mobile phase at a flow rate of 1 ml/min. UV detection was at 300 nm. The method was validated for accuracy, precision, linearity, specificity. Validation revealed the method is specific, accurate, precise, reliable and reproducible. Good linear correlation coefficients (r(2)>0.997) were obtained for calibration plots in the ranges tested. Limit of detection was 4.35 μg and limit of quantification was 16.56 μg. Intra and inter-day RSD of retention times and peak areas was less than 1.24% and recovery was between 95.05 and 101.05%. The established HPLC method is appropriate enabling efficient quantitative analysis of karanjin in Pongamia pinnata leaves.

Development and Validation of an HPLC Method for Karanjin in Pongamia pinnata linn. Leaves

PubMed Central

Katekhaye, S; Kale, M. S.; Laddha, K. S.

2012-01-01

A rapid, simple and specific reversed-phase HPLC method has been developed for analysis of karanjin in Pongamia pinnata Linn. leaves. HPLC analysis was performed on a C18 column using an 85:13.5:1.5 (v/v) mixtures of methanol, water and acetic acid as isocratic mobile phase at a flow rate of 1 ml/min. UV detection was at 300 nm. The method was validated for accuracy, precision, linearity, specificity. Validation revealed the method is specific, accurate, precise, reliable and reproducible. Good linear correlation coefficients (r2>0.997) were obtained for calibration plots in the ranges tested. Limit of detection was 4.35 μg and limit of quantification was 16.56 μg. Intra and inter-day RSD of retention times and peak areas was less than 1.24% and recovery was between 95.05 and 101.05%. The established HPLC method is appropriate enabling efficient quantitative analysis of karanjin in Pongamia pinnata leaves. PMID:23204626

Quantitation of DNA adducts by stable isotope dilution mass spectrometry

PubMed Central

Tretyakova, Natalia; Goggin, Melissa; Janis, Gregory

2012-01-01

Exposure to endogenous and exogenous chemicals can lead to the formation of structurally modified DNA bases (DNA adducts). If not repaired, these nucleobase lesions can cause polymerase errors during DNA replication, leading to heritable mutations potentially contributing to the development of cancer. Due to their critical role in cancer initiation, DNA adducts represent mechanism-based biomarkers of carcinogen exposure, and their quantitation is particularly useful for cancer risk assessment. DNA adducts are also valuable in mechanistic studies linking tumorigenic effects of environmental and industrial carcinogens to specific electrophilic species generated from their metabolism. While multiple experimental methodologies have been developed for DNA adduct analysis in biological samples – including immunoassay, HPLC, and 32P-postlabeling – isotope dilution high performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS) generally has superior selectivity, sensitivity, accuracy, and reproducibility. As typical DNA adducts concentrations in biological samples are between 0.01 – 10 adducts per 108 normal nucleotides, ultrasensitive HPLC-ESI-MS/MS methodologies are required for their analysis. Recent developments in analytical separations and biological mass spectrometry – especially nanoflow HPLC, nanospray ionization MS, chip-MS, and high resolution MS – have pushed the limits of analytical HPLC-ESI-MS/MS methodologies for DNA adducts, allowing researchers to accurately measure their concentrations in biological samples from patients treated with DNA alkylating drugs and in populations exposed to carcinogens from urban air, drinking water, cooked food, alcohol, and cigarette smoke. PMID:22827593

A clean-up method by photocatalysis for HPLC analysis of iprodione in dry basil.

PubMed

Maeda, Osamu; Oikawa, Chie; Shiomi, Nobuo; Toriba, Akira; Hayakawa, Kazuichi

2008-08-01

Titanium dioxide was used as a photocatalyst to decompose interfering substances for a quantitative analysis of a fungicide (iprodione) in dry basil by HPLC. A quartz vial containing basil extract and titanium dioxide was irradiated with black light. The interfering substances were almost completely decomposed by 180 min of irradiation, whereas 88.3% of iprodione remained. The recovery of iprodione was 102.6% by the proposed method in basil extracts. This may have been due to different decomposition rates of the analyte and interfering substances.

[Data fusion and multi-components quantitative analysis for identification and quality evaluation of Gentiana rigescens from different geographical origins].

PubMed

Wang, Qin-Qin; Shen, Tao; Zuo, Zhi-Tian; Huang, Heng-Yu; Wang, Yuan-Zhong

2018-03-01

The accumulation of secondary metabolites of traditional Chinese medicine (TCM) is closely related to its origins. The identification of origins and multi-components quantitative evaluation are of great significance to ensure the quality of medicinal materials. In this study, the identification of Gentiana rigescens from different geographical origins was conducted by data fusion of Fourier transform infrared (FTIR) spectroscopy and high performance liquid chromatography (HPLC) in combination of partial least squares discriminant analysis; meanwhile quantitative analysis of index components was conducted to provide an accurate and comprehensive identification and quality evaluation strategy for selecting the best production areas of G. rigescens. In this study, the FTIR and HPLC information of 169 G. rigescens samples from Yunnan, Sichuan, Guangxi and Guizhou Provinces were collected. The raw infrared spectra were pre-treated by multiplicative scatter correction, standard normal variate (SNV) and Savitzky-Golay (SG) derivative. Then the performances of FTIR, HPLC, and low-level data fusion and mid-level data fusion for identification were compared, and the contents of gentiopicroside, swertiamarin, loganic acid and sweroside were determined by HPLC. The results showed that the FTIR spectra of G. rigescens from different geographical origins were different, and the best pre-treatment method was SNV+SG-derivative (second derivative, 15 as the window parameter, and 2 as the polynomial order). The results showed that the accuracy rate of low- and mid-level data fusion (96.43%) in prediction set was higher than that of FTIR and HPLC (94.64%) in prediction set. In addition, the accuracy of low-level data fusion (100%) in the training set was higher than that of mid-level data fusion (99.12%) in training set. The contents of the iridoid glycosides in Yunnan were the highest among different provinces. The average content of gentiopicroside, as a bioactive marker in Chinese pharmacopoeia, was 47.40 mg·g⁻¹, and the maximum was 79.83 mg·g⁻¹. The contents of loganic acid, sweroside and gentiopicroside in Yunnan were significantly different from other provinces ( P <0.05). In comparison of total content of iridoid glycosides in G. rigescens with different geographical origins in Yunnan, it was found that the amount of iridoid glycosides was higher in Eryuan Dali (68.59 mg·g⁻¹) and Yulong Lijiang (66.68 mg·g⁻¹), significantly higher than that in Wuding Chuxiong (52.99 mg·g⁻¹), Chengjiang Yuxi (52.29 mg·g⁻¹) and Xundian Kunming (46.71 mg·g⁻¹) ( P <0.05), so these two places can be used as a reference region for screening cultivation and excellent germplasm resources of G. rigescens. A comprehensive and accurate method was established by data fusion of HPLC-FTIR and quantitative analysis of HPLC for identification and quality evaluation of G. rigescens, which could provide a support for the development and utilization of G. rigescens. Copyright© by the Chinese Pharmaceutical Association.

Quantitative analysis of naphthenic acids in water by liquid chromatography-accurate mass time-of-flight mass spectrometry.

PubMed

Hindle, Ralph; Noestheden, Matthew; Peru, Kerry; Headley, John

2013-04-19

This study details the development of a routine method for quantitative analysis of oil sands naphthenic acids, which are a complex class of compounds found naturally and as contaminants in oil sands process waters from Alberta's Athabasca region. Expanding beyond classical naphthenic acids (CnH2n-zO2), those compounds conforming to the formula CnH2n-zOx (where 2≥x≤4) were examined in commercial naphthenic acid and environmental water samples. HPLC facilitated a five-fold reduction in ion suppression when compared to the more commonly used flow injection analysis. A comparison of 39 model naphthenic acids revealed significant variability in response factors, demonstrating the necessity of using naphthenic acid mixtures for quantitation, rather than model compounds. It was also demonstrated that naphthenic acidic heterogeneity (commercial and environmental) necessitates establishing a single NA mix as the standard against which all quantitation is performed. The authors present the first ISO17025 accredited method for the analysis of naphthenic acids in water using HPLC high resolution accurate mass time-of-flight mass spectrometry. The method detection limit was 1mg/L total oxy-naphthenic acids (Sigma technical mix). Copyright © 2013 Elsevier B.V. All rights reserved.

LC-NMR Technique in the Analysis of Phytosterols in Natural Extracts

PubMed Central

Horník, Štěpán; Sajfrtová, Marie; Sýkora, Jan; Březinová, Anna; Wimmer, Zdeněk

2013-01-01

The ability of LC-NMR to detect simultaneously free and conjugated phytosterols in natural extracts was tested. The advantages and disadvantages of a gradient HPLC-NMR method were compared to the fast composition screening using SEC-NMR method. Fractions of free and conjugated phytosterols were isolated and analyzed by isocratic HPLC-NMR methods. The results of qualitative and quantitative analyses were in a good agreement with the literature data. PMID:24455424

Determination of the Antibiotic Oxytetracycline in Commercial Milk by Solid-Phase Extraction: A High-Performance Liquid Chromatography (HPLC) Experiment for Quantitative Instrumental Analysis

ERIC Educational Resources Information Center

Mei-Ratliff, Yuan

2012-01-01

Trace levels of oxytetracylcine spiked into commercial milk samples are extracted, cleaned up, and preconcentrated using a C[subscript 18] solid-phase extraction column. The extract is then analyzed by a high-performance liquid chromatography (HPLC) instrument equipped with a UV detector and a C[subscript 18] column (150 mm x 4.6 mm x 3.5 [mu]m).…

Quantitation of polymethoxylated flavones in orange juice by high-performance liquid chromatography.

PubMed

Rouseff, R L; Ting, S V

1979-08-01

A quantitative high-performance liquid chromatographic (HPLC) procedure for the determination of the five major polymethoxylated flavones (PMFs) in orange juice has been developed. It employs a unique ternary solvent system with coupled UV-fluorescence detection. The dual detectors were employed to determine the presence of interfering substances and served as a cross check on quantitation. Stop flow UV and fluorescence scanning was used to identify peaks and determine the presence of impurities. Although all five citrus PMFs fluoresce, some HPLC fluorescence peaks were too small to be of much practical use. All five citrus PMFs could be quantitated satisfactorily with the fixed wavelength UV (313 nm) detector. The HPLC procedure has been used to evaluate each step in the preparation. The optimum extracting solvent was selected and one time consuming step was eliminated, as it was found to be unnecessary. HPLC values for nobiletin and sinensetin are in good agreement with the thin-layer chromatographic (TLC) values in the literature. HPLC values for the other three flavones were considerably lower than those reported in the literature. The HPLC procedure is considerably faster than the TLC procedure with equal or superior precision and accuracy.

[Study on ethnic medicine quantitative reference herb,Tibetan medicine fruits of Capsicum frutescens as a case].

PubMed

Zan, Ke; Cui, Gan; Guo, Li-Nong; Ma, Shuang-Cheng; Zheng, Jian

2018-05-01

High price and difficult to get of reference substance have become obstacles to HPLC assay of ethnic medicine. A new method based on quantitative reference herb (QRH) was proposed. Specific chromatograms in fruits of Capsicum frutescens were employed to determine peak positions, and HPLC quantitative reference herb was prepared from fruits of C. frutescens. The content of capsaicin and dihydrocapsaicin in the quantitative control herb was determined by HPLC. Eleven batches of fruits of C. frutescens were analyzed with quantitative reference herb and reference substance respectively. The results showed no difference. The present method is feasible for quality control of ethnic medicines and quantitative reference herb is suitable to replace reference substances in assay. Copyright© by the Chinese Pharmaceutical Association.

Rapid, Standardized Method for Determination of Mycobacterium tuberculosis Drug Susceptibility by Use of Mycolic Acid Analysis▿

PubMed Central

Parrish, Nicole; Osterhout, Gerard; Dionne, Kim; Sweeney, Amy; Kwiatkowski, Nicole; Carroll, Karen; Jost, Kenneth C.; Dick, James

2007-01-01

Multidrug-resistant (MDR) Mycobacterium tuberculosis and extrensively drug-resistant (XDR) M. tuberculosis are emerging public health threats whose threats are compounded by the fact that current techniques for testing the susceptibility of M. tuberculosis require several days to weeks to complete. We investigated the use of high-performance liquid chromatography (HPLC)-based quantitation of mycolic acids as a means of rapidly determining drug resistance and susceptibility in M. tuberculosis. Standard susceptibility testing and determination of the MICs of drug-susceptible (n = 26) and drug-resistant M. tuberculosis strains, including MDR M. tuberculosis strains (n = 34), were performed by using the Bactec radiometric growth system as the reference method. The HPLC-based susceptibilities of the current first-line drugs, isoniazid (INH), rifampin (RIF), ethambutol (EMB), and pyrazinamide (PZA), were determined. The vials were incubated for 72 h, and aliquots were removed for HPLC analysis by using the Sherlock mycobacterial identification system. HPLC quantitation of total mycolic acid peaks (TMAPs) was performed with treated and untreated cultures. At 72 h, the levels of agreement of the HPLC method with the reference method were 99.5% for INH, EMB, and PZA and 98.7% for RIF. The inter- and intra-assay reproducibilities varied by drug, with an average precision of 13.4%. In summary, quantitation of TMAPs is a rapid, sensitive, and accurate method for antibiotic susceptibility testing of all first-line drugs currently used against M. tuberculosis and offers the potential of providing susceptibility testing results within hours, rather than days or weeks, for clinical M. tuberculosis isolates. PMID:17913928

Methods of analysis by the U.S. Geological Survey Organic Geochemistry Research Group; determination of chloroacetanilide herbicide metabolites in water using high-performance liquid chromatography-diode array detection and high-performance liquid chromatography/mass spectrometry

USGS Publications Warehouse

Zimmerman, L.R.; Hostetler, K.A.; Thurman, E.M.

2000-01-01

Analytical methods using high-performance liquid chromatography-diode array detection (HPLC-DAD) and high-performance liquid chromatography/mass spectrometry (HPLC/MS) were developed for the analysis of the following chloroacetanilide herbicide metabolites in water: acetochlor ethanesulfonic acid (ESA), acetochlor oxanilic acid (OXA), alachlor ESA, alachlor OXA, metolachlor ESA, and metolachlor OXA. Good precision and accuracy were demonstrated for both the HPLC-DAD and HPLC/MS methods in reagent water, surface water, and ground water. The mean HPLC-DAD recoveries of the chloroacetanilide herbicide metabolites from water samples spiked at 0.25, 0.50, and 2.0 mg/L (micrograms per liter) ranged from 84 to 112 percent, with relative standard deviations of 18 percent or less. The mean HPLC/MS recoveries of the metabolites from water samples spiked at 0.05, 0.20, and 2.0 mg/L ranged from 81 to 125 percent, with relative standard deviations of 20 percent or less. The limit of quantitation (LOQ) for all metabolites using the HPLC-DAD method was 0.20 mg/L, whereas the LOQ using the HPLC/MS method was 0.05 mg/L. These metabolite-determination methods are valuable for acquiring information about water quality and the fate and transport of the parent chloroacetanilide herbicides in water.

Repeatability Assessment by ISO 11843-7 in Quantitative HPLC for Herbal Medicines.

PubMed

Chen, Liangmian; Kotani, Akira; Hakamata, Hideki; Tsutsumi, Risa; Hayashi, Yuzuru; Wang, Zhimin; Kusu, Fumiyo

2015-01-01

We have proposed an assessment methods to estimate the measurement relative standard deviation (RSD) of chromatographic peaks in quantitative HPLC for herbal medicines by the methodology of ISO 11843 Part 7 (ISO 11843-7:2012), which provides detection limits stochastically. In quantitative HPLC with UV detection (HPLC-UV) of Scutellaria Radix for the determination of baicalin, the measurement RSD of baicalin by ISO 11843-7:2012 stochastically was within a 95% confidence interval of the statistically obtained RSD by repetitive measurements (n = 6). Thus, our findings show that it is applicable for estimating of the repeatability of HPLC-UV for determining baicalin without repeated measurements. In addition, the allowable limit of the "System repeatability" in "Liquid Chromatography" regulated in a pharmacopoeia can be obtained by the present assessment method. Moreover, the present assessment method was also successfully applied to estimate the measurement RSDs of quantitative three-channel liquid chromatography with electrochemical detection (LC-3ECD) of Chrysanthemi Flos for determining caffeoylquinic acids and flavonoids. By the present repeatability assessment method, reliable measurement RSD was obtained stochastically, and the experimental time was remarkably reduced.

Simultaneous Estimation of Withaferin A and Z-Guggulsterone in Marketed Formulation by RP-HPLC.

PubMed

Agrawal, Poonam; Vegda, Rashmi; Laddha, Kirti

2015-07-01

A simple, rapid, precise and accurate high-performance liquid chromatography (HPLC) method was developed for simultaneous estimation of withaferin A and Z-guggulsterone in a polyherbal formulation containing Withania somnifera and Commiphora wightii. The chromatographic separation was achieved on a Purosphere RP-18 column (particle size 5 µm) with a mobile phase consisting of Solvent A (acetonitrile) and Solvent B (water) with the following gradients: 0-7 min, 50% A in B; 7-9 min, 50-80% A in B; 9-20 min, 80% A in B at a flow rate of 1 mL/min and detection at 235 nm. The marker compounds were well separated on the chromatogram within 20 min. The results obtained indicate accuracy and reliability of the developed simultaneous HPLC method for the quantification of withaferin A and Z-guggulsterone. The proposed method was found to be reproducible, specific, precise and accurate for simultaneous estimation of these marker compounds in a combined dosage form. The HPLC method was appropriate and the two markers are well resolved, enabling efficient quantitative analysis of withaferin A and Z-guggulsterone. The method can be successively used for quantitative analysis of these two marker constituents in combination of marketed polyherbal formulation. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Evaluation of multiple reaction monitoring cubed for the analysis of tachykinin related peptides in rat spinal cord using a hybrid triple quadrupole-linear ion trap mass spectrometer.

PubMed

Pailleux, Floriane; Beaudry, Francis

2014-02-01

Targeted peptide methods generally use HPLC-MS/MRM approaches. Although dependent on the instrumental resolution, interferences may occur while performing analysis of complex biological matrices. HPLC-MS/MRM(3) is a technique, which provides a significantly better selectivity, compared with HPLC-MS/MRM assay. HPLC-MS/MRM(3) allows the detection and quantitation by enriching standard MRM with secondary product ions that are generated within the linear ion trap. Substance P (SP) and neurokinin A (NKA) are tachykinin peptides playing a central role in pain transmission. The objective of this study was to verify whether HPLC-MS/MRM(3) could provide significant advantages over a more traditional HPLC-MS/MRM assay for the quantification of SP and NKA in rat spinal cord. The results suggest that reconstructed MRM(3) chromatograms display significant improvements with the nearly complete elimination of interfering peaks but the sensitivity (i.e. signal-to-noise ratio) was severely reduced. The precision (%CV) observed was between 3.5% and 24.1% using HPLC-MS/MRM and in the range of 4.3-13.1% with HPLC-MS/MRM(3), for SP and NKA. The observed accuracy was within 10% of the theoretical concentrations tested. HPLC-MS/MRM(3) may improve the assay sensitivity to detect difference between samples by reducing significantly the potential of interferences and therefore reduce instrumental errors. Copyright © 2014 Elsevier B.V. All rights reserved.

Simultaneous determination of rhamnose, xylitol, arabitol, fructose, glucose, inositol, sucrose, maltose in jujube (Zizyphus jujube Mill.) extract: comparison of HPLC-ELSD, LC-ESI-MS/MS and GC-MS.

PubMed

Sun, Shihao; Wang, Hui; Xie, Jianping; Su, Yue

2016-01-01

Jujube extract is commonly used as a food additive and flavoring. The sensory properties of the extract, especially sweetness, are a critical factor determining the product quality and therefore affecting consumer acceptability. Small molecular carbohydrates make major contribution to the sweetness of the jujube extract, and their types and contents in the extract have direct influence on quality of the product. So, an appropriate qualitative and quantitative method for determination of the carbohydrates is vitally important for quality control of the product. High performance liquid chromatography-evaporative light scattering detection (HPLC-ELSD), liquid chromatography-electronic spay ionization tandem mass spectrometry (LC-ESI-MS/MS), and gas chromatography-mass spectrometry (GC-MS) methods have been developed and applied to determining small molecular carbohydrates in jujube extract, respectively. Eight sugars and alditols were identified from the extract, including rhamnose, xylitol, arabitol, fructose, glucose, inositol, sucrose, and maltose. Comparisons were carried out to investigate the performance of the methods. Although the methods have been found to perform satisfactorily, only three sugars (fructose, glucose and inositol) could be detected by all these methods. Meanwhile, a similar quantitative result for the three sugars can be obtained by the methods. Eight sugars and alditols in the jujube extract were determined by HPLC-ELSD, LC-ESI-MS/MS and GC-MS, respectively. The LC-ELSD method and the LC-ESI-MS/MS method with good precision and accuracy were suitable for quantitative analysis of carbohydrates in jujube extract; although the performance of the GC-MS method for quantitative analysis was inferior to the other methods, it has a wider scope in qualitative analysis. A multi-analysis technique should be adopted in order to obtain complete constituents of about the carbohydrates in jujube extract, and the methods should be employed according to the purpose of analysis.

Quantitative Determination of α-Arbutin, β-Arbutin, Kojic Acid, Nicotinamide, Hydroquinone, Resorcinol, 4-Methoxyphenol, 4-Ethoxyphenol, and Ascorbic Acid from Skin Whitening Products by HPLC-UV.

PubMed

Wang, Yan-Hong; Avonto, Cristina; Avula, Bharathi; Wang, Mei; Rua, Diego; Khan, Ikhlas A

2015-01-01

An HPLC-UV method was developed for the quantitative analysis of nine skin whitening agents in a single injection. These compounds are α-arbutin, β-arbutin, kojic acid, nicotinamide, resorcinol, ascorbic acid, hydroquinone, 4-methoxyphenol, and 4-ethoxyphenol. The separation was achieved on a reversed-phase C18 column within 30 min. The mobile phase was composed of water and methanol, both containing 0.1% acetic acid (v/v). The stability of the analytes was evaluated at different pH values between 2.3 and 7.6, and the extraction procedure was validated for different types of skin whitening product matrixes, which included two creams, a soap bar, and a capsule. The best solvent system for sample preparation was 20 mM NaH2PO4 containing 10% methanol at pH 2.3. The analytical method was validated for accuracy, precision, LOD, and LOQ. The developed HPLC-UV method was applied for the quantitation of the nine analytes in 59 skin whitening products including creams, lotions, sera, foams, gels, mask sheets, soap bars, tablets, and capsules.

Analysis of the extracts of Isatis tinctoria by new analytical approaches of HPLC, MS and NMR.

PubMed

Zhou, Jue; Qu, Fan

2011-01-01

The methods of extraction, separation and analysis of alkaloids and indole glucosinolates (GLs) ofIsatis tinctoria were reviewed. Different analytical approaches such as High-pressure Liquid Chromatography (HPLC), Liquid Chromatography with Electrospray Ionization Mass Spectrometry (LC/ESI/MS), Electrospray Ionization Time-Of-Flight Mass Spectrometry (ESI-TOF-MS), and Nuclear Magnetic Resonance (NMR) were used to validate and identity of these constituents. These methods provide rapid separation, identification and quantitative measurements of alkaloids and GLs of Isatis tinctoria. By connection with different detectors to HPLC such as PDA, ELSD, ESI- and APCI-MS in positive and negative ion modes, complicated compounds could be detected with at least two independent detection modes. The molecular formula can be derived in a second step of ESI-TOF-MS data. But for some constituents, UV and MS cannot provide sufficient structure identification. After peak purification, NMR by semi-preparative HPLC can be used as a complementary method.

Isolation and quantification of Quillaja saponaria Molina saponins and lipids in iscom-matrix and iscoms.

PubMed

Behboudi, S; Morein, B; Rönnberg, B

1995-12-01

In the iscom, multiple copies of antigen are attached by hydrophobic interaction to a matrix which is built up by Quillaja triterpenoid saponins and lipids. Thus, the iscom presents antigen in multimeric form in a small particle with a built-in adjuvant resulting in a highly immunogenic antigen formulation. We have designed a chloroform-methanol-water extraction procedure to isolate the triterpenoid saponins and lipids incorporated into iscom-matrix and iscoms. The triterpenoids in the triterpenoid phase were quantitated using orcinol sulfuric acid detecting their carbohydrate chains and by HPLC. The cholesterol and phosphatidylcholine in the lipid phase were quantitated by HPLC and a commercial colorimetric method for the cholesterol. The quantitative methods showed an almost total separation and recovery of triterpenoids and lipids in their respective phases, while protein was detected in all phases after extraction. The protein content was determined by the method of Lowry and by amino acid analysis. Amino acid analysis was shown to be the reliable method of the two to quantitate proteins in iscoms. In conclusion, simple, reproducible and efficient procedures have been designed to isolate and quantitate the triterpenoids and lipids added for preparation of iscom-matrix and iscoms. The procedures described should also be useful to adequately define constituents in prospective vaccines.

A Novel HPLC Method for the Concurrent Analysis and Quantitation of Seven Water-Soluble Vitamins in Biological Fluids (Plasma and Urine): A Validation Study and Application

PubMed Central

Grotzkyj Giorgi, Margherita; Howland, Kevin; Martin, Colin; Bonner, Adrian B.

2012-01-01

An HPLC method was developed and validated for the concurrent detection and quantitation of seven water-soluble vitamins (C, B1, B2, B5, B6, B9, B12) in biological matrices (plasma and urine). Separation was achieved at 30°C on a reversed-phase C18-A column using combined isocratic and linear gradient elution with a mobile phase consisting of 0.01% TFA aqueous and 100% methanol. Total run time was 35 minutes. Detection was performed with diode array set at 280 nm. Each vitamin was quantitatively determined at its maximum wavelength. Spectral comparison was used for peak identification in real samples (24 plasma and urine samples from abstinent alcohol-dependent males). Interday and intraday precision were <4% and <7%, respectively, for all vitamins. Recovery percentages ranged from 93% to 100%. PMID:22536136

A novel HPLC method for the concurrent analysis and quantitation of seven water-soluble vitamins in biological fluids (plasma and urine): a validation study and application.

PubMed

Giorgi, Margherita Grotzkyj; Howland, Kevin; Martin, Colin; Bonner, Adrian B

2012-01-01

An HPLC method was developed and validated for the concurrent detection and quantitation of seven water-soluble vitamins (C, B(1), B(2), B(5), B(6), B(9), B(12)) in biological matrices (plasma and urine). Separation was achieved at 30°C on a reversed-phase C18-A column using combined isocratic and linear gradient elution with a mobile phase consisting of 0.01% TFA aqueous and 100% methanol. Total run time was 35 minutes. Detection was performed with diode array set at 280 nm. Each vitamin was quantitatively determined at its maximum wavelength. Spectral comparison was used for peak identification in real samples (24 plasma and urine samples from abstinent alcohol-dependent males). Interday and intraday precision were <4% and <7%, respectively, for all vitamins. Recovery percentages ranged from 93% to 100%.

Differentiation of Cuscuta chinensis and Cuscuta australis by HPLC-DAD-MS analysis and HPLC-UV quantitation.

PubMed

He, Xianghui; Yang, Wenzhi; Ye, Min; Wang, Qing; Guo, Dean

2011-11-01

Cuscuta chinensis and Cuscuta australis, the two botanical sources of the Chinese herbal medicine Tu-Si-Zi, were distinguished from each other based on qualitative and quantitative chemical analysis. By HPLC‑DAD‑MS, a total of 36 compounds were characterized from these two Cuscuta species, including 14 flavonoids, 17 quinic acid derivatives, and 5 lignans. In addition, HPLC‑UV was applied to determine seven major compounds (6 flavonoids plus chlorogenic acid) in 27 batches of Tu-Si-Zi. The results revealed that the amounts of the three classes of compounds varied significantly between the species. C. australis contained more flavonoids but less quinic acid derivatives and lignans than C. chinensis. Particularly, the amounts of kaempferol and astragalin in C. australis were remarkably higher than in C. chinensis. This finding could be valuable for the quality control of Tu-Si-Zi. © Georg Thieme Verlag KG Stuttgart · New York.

From the street to the laboratory: analytical profiles of methoxetamine, 3-methoxyeticyclidine and 3-methoxyphencyclidine and their determination in three biological matrices.

PubMed

De Paoli, Giorgia; Brandt, Simon D; Wallach, Jason; Archer, Roland P; Pounder, Derrick J

2013-06-01

Three psychoactive arylcyclohexylamines, advertised as "research chemicals," were obtained from an online retailer and characterized by gas chromatography ion trap electron and chemical ionization mass spectrometry, nuclear magnetic resonance spectroscopy and diode array detection. The three phencyclidines were identified as 2-(ethylamino)-2-(3-methoxyphenyl)cyclohexanone (methoxetamine), N-ethyl-1-(3-methoxyphenyl)cyclohexanamine and 1-[1-(3-methoxyphenyl)cyclohexyl]piperidine. A qualitative/quantitative method of analysis was developed and validated using liquid chromatography (HPLC) electrospray tandem mass spectrometry and ultraviolet (UV) detection for the determination of these compounds in blood, urine and vitreous humor. HPLC-UV proved to be a robust, accurate and precise method for the qualitative and quantitative analysis of these substances in biological fluids (0.16-5.0 mg/L), whereas the mass spectrometer was useful as a confirmatory tool.

Quantitative determination of a chemically modified hammerhead ribozyme in blood plasma using 96-well solid-phase extraction coupled with high-performance liquid chromatography or capillary gel electrophoresis.

PubMed

Bellon, L; Maloney, L; Zinnen, S P; Sandberg, J A; Johnson, K E

2000-08-01

Versatile bioanalytical assays to detect chemically stabilized hammerhead ribozyme and putative ribozyme metabolites from plasma are described. The extraction protocols presented are based on serial solid-phase extractions performed on a 96-well plate format and are compatible with either IEX-HPLC or CGE back-end analysis. A validation of both assays confirmed that both the HPLC and the CGE methods possess the required linearity, accuracy, and precision to accurately measure concentrations of hammerhead ribozyme extracted from plasma. These methods should be of general use to detect and quantitate ribozymes from other biological fluids such as serum and urine. Copyright 2000 Academic Press.

High-Pressure Liquid Chromatography: Quantitative Analysis of Chinese Herbal Medicine

ERIC Educational Resources Information Center

Chan, W. F.; Lin, C. W.

2007-01-01

An HPLC undergraduate experiment on the analysis of traditional Chinese medicine (TCM) has been developed. Two commonly used herbs ("glycyrrhizae radix" and "cinnamomi ramulus") are studied. Glycyrrhizin, cinnamic acid, and cinnamaldehyde are chosen as markers for the herbs. The dried herbs in their natural state and a TCM…

Quantitative analysis of major dibenzocyclooctane lignans in Schisandrae fructus by online TLC-DART-MS.

PubMed

Kim, Hye Jin; Oh, Myung Sook; Hong, Jongki; Jang, Young Pyo

2011-01-01

Direct analysis in real time (DART) ion source is a powerful ionising technique for the quick and easy detection of various organic molecules without any sample preparation steps, but the lack of quantitation capacity limits its extensive use in the field of phytochemical analysis. To improvise a new system which utilize DART-MS as a hyphenated detector for quantitation. A total extract of Schisandra chinensis fruit was analyzed on a TLC plate and three major lignan compounds were quantitated by three different methods of UV densitometry, TLC-DART-MS and HPLC-UV to compare the efficiency of each method. To introduce the TLC plate into the DART ion source at a constant velocity, a syringe pump was employed. The DART-MS total ion current chromatogram was recorded for the entire TLC plate. The concentration of each lignan compound was calculated from the calibration curve established with standard compound. Gomisin A, gomisin N and schisandrin were well separated on a silica-coated TLC plate and the specific ion current chromatograms were successfully acquired from the TLC-DART-MS system. The TLC-DART-MS system for the quantitation of natural products showed better linearity and specificity than TLC densitometry, and consumed less time and solvent than conventional HPLC method. A hyphenated system for the quantitation of phytochemicals from crude herbal drugs was successfully established. This system was shown to have a powerful analytical capacity for the prompt and efficient quantitation of natural products from crude drugs. Copyright © 2010 John Wiley & Sons, Ltd.

Simultaneous qualitative and quantitative analysis of phenolic acids and flavonoids for the quality control of Apocynum venetum L. leaves by HPLC-DAD-ESI-IT-TOF-MS and HPLC-DAD.

PubMed

An, Haijuan; Wang, Hong; Lan, Yuexiang; Hashi, Yuki; Chen, Shizhong

2013-11-01

A reliable method based on high performance liquid chromatography-diode array detector-electrospray ionization-ion trap-time of flight-mass spectrometry (HPLC-DAD-ESI-IT-TOF-MS) was developed for the identification of phenolic acids and flavonoids in Apocynum venetum L. leaves and its adulterant, Pocynum hendersonii (Hook. f.) Woodson leaves. A total of 21 compounds were identified or tentatively identified, including 4 phenolic acids and 17 flavonoids. 3-O-caffeoylquinic acid (3-CQA) and caffeic acid were detected for the first time in A. venetum leaves; 4-O-caffeoylquinic acid (4-CQA), 3-CQA, caffeic acid, quercetin-3-O-(6"-O-malonyl)-galactoside, quercetin-3-O-(6"-O-malonyl)-glucoside, kaempferol-3-O-(6"-O-malonyl)-glucoside, kaempferol-3-O-(6"-O-acetyl)-glucoside, and kaempferol-3-O-dihexoside were detected for the first time in P. hendersonii leaves. Cluster analysis was employed to analyze 24 batches of A. venetum leaves and 5 batches of P. hendersonii leaves collected from various regions in China. The analysis, which was based on the 21 compounds, indicated that profiles of these compounds were distinct between the two species, and among A. venetum leaf samples from different origins. 18 of these 21 compounds were selected as the markers and simultaneously analyzed by HPLC-DAD for the first time. The quantitative analytical method was validated and subsequently applied to the comprehensive quality evaluation of 24 batches of A. venetum leaves. © 2013 Elsevier B.V. All rights reserved.

Analytical capabilities of high performance liquid chromatography - Atmospheric pressure photoionization - Orbitrap mass spectrometry (HPLC-APPI-Orbitrap-MS) for the trace determination of novel and emerging flame retardants in fish.

PubMed

Zacs, D; Bartkevics, V

2015-10-22

A new analytical method was established and validated for the analysis of 27 brominated flame retardants (BFRs), including so called "emerging" and "novel" BFRs (EBFRs and NBFRs) in fish samples. High performance liquid chromatography (HPLC) coupled to Orbitrap mass spectrometry (Orbitrap-MS) employing atmospheric pressure photoionization (APPI) interface operated in negative mode was used for the identification/quantitation of contaminants. HPLC-Orbitrap-MS analysis provided a fast separation of selected analytes within 14 min, thus demonstrating a high throughput processing of samples. The developed methodology was tested by intralaboratory validation in terms of recovery, repeatability, linear calibration ranges, instrumental and method limits of quantitation (i-LOQ and m-LOQ), and where possible, trueness was verified by analysis of certified reference materials (CRMs). Recoveries of analytes were between 80 and 119%, while the repeatability in terms of relative standard deviations (RSDs) was in the range from 1.2 to 15.5%. The measured values for both analyzed CRMs agreed with the provided consensus values, revealing the recovery of reference concentrations in 72-119% range. The elaborated method met the sensitivity criterion according to Commission Recommendation 2014/118/EU on monitoring of BFRs in food products for majority of the compounds. The concentrations of polybrominated diphenyl ethers (PBDEs) in real samples determined by HPLC-APPI-Orbitrap-MS method and validated gas chromatography-high-resolution mass spectrometry (GC-HRMS) method were found to be in a good agreement. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparison of UPLC and HPLC methods for determination of vitamin C.

PubMed

Klimczak, Inga; Gliszczyńska-Świgło, Anna

2015-05-15

Ultra performance liquid chromatography (UPLC) and high-performance liquid chromatography (HPLC) methods for determination of ascorbic acid (AA) and total AA (TAA) contents (as the sum of AA and dehydroascorbic acid (DHAA) after its reduction to AA) in fruit beverages and in pharmaceutical preparations were compared. Both methods are rapid: total time of analysis was 15 and 6 min for HPLC and UPLC methods, respectively. The methods were validated in terms of linearity, instrument precision, limits of detection (LOD) and quantification (LOQ), accuracy and recovery. Intra- and inter-day instrument precisions for fruit juices, expressed as RSD, were 2.2% and 2.4% for HPLC, respectively, and 1.7% and 1.9% for UPLC, respectively. For vitamin C tablets, inter- and intra-day precisions were 0.4% and 0.5%, respectively (HPLC), and 0.5% and 0.3%, respectively (UPLC). Both methods were sensitive: LOD was 0.049 μg/mL for HPLC and 0.024 μg/mL for UPLC while LOQs were 0.149 and 0.073 μg/mL for HPLC and UPLC, respectively. These methods could be useful in the routine qualitative and quantitative analysis of AA or TAA in pharmaceutical preparations or fruit beverages. However, UPLC method is more sensitive, faster and consumes less eluent. Copyright © 2014 Elsevier Ltd. All rights reserved.

HPLC-MS and GC-MS analyses combined with orthogonal partial least squares to identify cytotoxic constituents from turmeric (Curcuma longa L.).

PubMed

Jiang, Jianlan; Zhang, Huan; Li, Zidan; Zhang, Xiaohang; Su, Xin; Li, Yan; Qiao, Bin; Yuan, Yingjin

2013-08-01

We investigated the fingerprints of 48 batches of turmeric total extracts (TTE) by HPLC-MS-MS and GC-MS analyses and 43 characteristic peaks (22 constituents from HPLC-MS-MS; 21 from GC-MS) were analyzed qualitatively and quantitatively. An MTT {3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide} assay was implemented to measure the cytotoxicity of the TTE against HeLa cells. Then we utilized orthogonal partial least squares analysis, which correlated the chemical composition of the TTE to its cytotoxic activity, to identify potential cytotoxic constituents from turmeric. The result showed that 19 constituents contributed significantly to the cytotoxicity. The obtained result was verified by canonical correlation analysis. Comparison with previous reports also indicated some interaction between the curcuminoids and sesquiterpenoids in turmeric.

Influence of growing conditions on metabolite profile of Ammi visnaga umbels with special reference to bioactive furanochromones and pyranocoumarins.

PubMed

Sellami, Hela Kallel; Napolitano, Assunta; Masullo, Milena; Smiti, Samira; Piacente, Sonia; Pizza, Cosimo

2013-11-01

The medicinal plant Ammi visnaga is a valuable source of furanochromones and pyranocoumarins used as vasodilator agents. Its ability to germinate under unfavourable growth conditions, such as saline soil and hypoxia characterizing clay soils and marshes ecosystems, prompted us to qualitatively characterize secondary metabolites in umbels of A. visnaga plants grown under different conditions (in field, hydroponically controlled, and contrasted by salinity and/or hypoxia) by HPLC-ESI/IT/MS(n) analysis. Subsequently, the quantitative analysis of the bioactive compounds, above all furanochromones and pyranocoumarins, was carried out by HPLC-ESI/QqQ/MS/MS. The results show the influence of growing conditions on the quali-quantitative profile of A. visnaga secondary metabolites and evidence that hydroponic culture leads to increased level of A. visnaga active principles. Furthermore, two furanochromones never reported before were identified and characterized by 1D- and 2D-NMR analysis. Copyright © 2013 Elsevier Ltd. All rights reserved.

Validation of quantitative method for azoxystrobin residues in green beans and peas.

PubMed

Abdelraheem, Ehab M H; Hassan, Sayed M; Arief, Mohamed M H; Mohammad, Somaia G

2015-09-01

This study presents a method validation for extraction and quantitative analysis of azoxystrobin residues in green beans and peas using HPLC-UV and the results confirmed by GC-MS. The employed method involved initial extraction with acetonitrile after the addition of salts (magnesium sulfate and sodium chloride), followed by a cleanup step by activated neutral carbon. Validation parameters; linearity, matrix effect, LOQ, specificity, trueness and repeatability precision were attained. The spiking levels for the trueness and the precision experiments were (0.1, 0.5, 3 mg/kg). For HPLC-UV analysis, mean recoveries ranged between 83.69% to 91.58% and 81.99% to 107.85% for green beans and peas, respectively. For GC-MS analysis, mean recoveries ranged from 76.29% to 94.56% and 80.77% to 100.91% for green beans and peas, respectively. According to these results, the method has been proven to be efficient for extraction and determination of azoxystrobin residues in green beans and peas. Copyright © 2015 Elsevier Ltd. All rights reserved.

Determination of vitamins D2 and D3 in selected food matrices by online high-performance liquid chromatography-gas chromatography-mass spectrometry (HPLC-GC-MS).

PubMed

Nestola, Marco; Thellmann, Andrea

2015-01-01

An online normal-phase liquid chromatography-gas chromatography-mass spectrometry (HPLC-GC-MS) method was developed for the determination of vitamins D2 and D3 in selected food matrices. Transfer of the sample from HPLC to GC was realized by large volume on-column injection; detection was performed with a time-of-flight mass spectrometer (TOF-MS). Typical GC problems in the determination of vitamin D such as sample degradation or sensitivity issues, previously reported in the literature, were not observed. Determination of total vitamin D content was done by quantitation of its pyro isomer based on an isotopically labelled internal standard (ISTD). Extracted ion traces of analyte and ISTD showed cross-contribution, but non-linearity of the calibration curve was not determined inside the chosen calibration range by selection of appropriate quantifier ions. Absolute limits of detection (LOD) and quantitation (LOQ) for vitamins D2 and D3 were calculated as approximately 50 and 150 pg, respectively. Repeatability with internal standard correction was below 2 %. Good agreement between quantitative results of an established high-performance liquid chromatography with UV detection (HPLC-UV) method and HPLC-GC-MS was found. Sterol-enriched margarine was subjected to HPLC-GC-MS and HPLC-MS/MS for comparison, because HPLC-UV showed strong matrix interferences. HPLC-GC-MS produced comparable results with less manual sample cleanup. In summary, online hyphenation of HPLC and GC allowed a minimization in manual sample preparation with an increase of sample throughput.

Ultra high performance liquid chromatography with ion-trap TOF-MS for the fast characterization of flavonoids in Citrus bergamia juice.

PubMed

Sommella, Eduardo; Pepe, Giacomo; Pagano, Francesco; Tenore, Gian Carlo; Dugo, Paola; Manfra, Michele; Campiglia, Pietro

2013-10-01

We have developed a fast ultra HPLC with ion-trap TOF-MS method for the analysis of flavonoids in Citrus bergamia juice. With respect to the typical methods for the analysis of these matrices based on conventional HPLC techniques, a tenfold faster separation was attained. The use of a core-shell particle column ensured high resolution within the fast analysis time of only 5 min. Unambiguous determination of flavonoid identity was obtained by the employment of a hybrid ion-trap TOF mass spectrometer with high mass accuracy (average error 1.69 ppm). The system showed good retention time and peak area repeatability, with maximum RSD% values of 0.36 and 3.86, respectively, as well as good linearity (R(2) ≥ 0.99). Our results show that ultra HPLC can be a useful tool for ultra fast qualitative/quantitative analysis of flavonoid compounds in citrus fruit juices. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Towards the development of a rapid, portable, surface enhanced Raman spectroscopy based cleaning verification system for the drug nelarabine.

PubMed

Corrigan, Damion K; Salton, Neale A; Preston, Chris; Piletsky, Sergey

2010-09-01

Cleaning verification is a scientific and economic problem for the pharmaceutical industry. A large amount of potential manufacturing time is lost to the process of cleaning verification. This involves the analysis of residues on spoiled manufacturing equipment, with high-performance liquid chromatography (HPLC) being the predominantly employed analytical technique. The aim of this study was to develop a portable cleaning verification system for nelarabine using surface enhanced Raman spectroscopy (SERS). SERS was conducted using a portable Raman spectrometer and a commercially available SERS substrate to develop a rapid and portable cleaning verification system for nelarabine. Samples of standard solutions and swab extracts were deposited onto the SERS active surfaces, allowed to dry and then subjected to spectroscopic analysis. Nelarabine was amenable to analysis by SERS and the necessary levels of sensitivity were achievable. It is possible to use this technology for a semi-quantitative limits test. Replicate precision, however, was poor due to the heterogeneous drying pattern of nelarabine on the SERS active surface. Understanding and improving the drying process in order to produce a consistent SERS signal for quantitative analysis is desirable. This work shows the potential application of SERS for cleaning verification analysis. SERS may not replace HPLC as the definitive analytical technique, but it could be used in conjunction with HPLC so that swabbing is only carried out once the portable SERS equipment has demonstrated that the manufacturing equipment is below the threshold contamination level.

Extraction efficiency and implications for absolute quantitation of propranolol in mouse brain, liver and kidney thin tissue sections using droplet-based liquid microjunction surface sampling-HPLC ESI-MS/MS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kertesz, Vilmos; Weiskittel, Taylor M.; Vavek, Marissa

Currently, absolute quantitation aspects of droplet-based surface sampling for thin tissue analysis using a fully automated autosampler/HPLC-ESI-MS/MS system are not fully evaluated. Knowledge of extraction efficiency and its reproducibility is required to judge the potential of the method for absolute quantitation of analytes from thin tissue sections. Methods: Adjacent thin tissue sections of propranolol dosed mouse brain (10- μm-thick), kidney (10- μm-thick) and liver (8-, 10-, 16- and 24- μm-thick) were obtained. Absolute concentration of propranolol was determined in tissue punches from serial sections using standard bulk tissue extraction protocols and subsequent HPLC separations and tandem mass spectrometric analysis. Thesemore » values were used to determine propranolol extraction efficiency from the tissues with the droplet-based surface sampling approach. Results: Extraction efficiency of propranolol using 10- μm-thick brain, kidney and liver thin tissues using droplet-based surface sampling varied between ~45-63%. Extraction efficiency decreased from ~65% to ~36% with liver thickness increasing from 8 μm to 24 μm. Randomly selecting half of the samples as standards, precision and accuracy of propranolol concentrations obtained for the other half of samples as quality control metrics were determined. Resulting precision ( ±15%) and accuracy ( ±3%) values, respectively, were within acceptable limits. In conclusion, comparative quantitation of adjacent mouse thin tissue sections of different organs and of various thicknesses by droplet-based surface sampling and by bulk extraction of tissue punches showed that extraction efficiency was incomplete using the former method, and that it depended on the organ and tissue thickness. However, once extraction efficiency was determined and applied, the droplet-based approach provided the required quantitation accuracy and precision for assay validations. Furthermore, this means that once the extraction efficiency was calibrated for a given tissue type and drug, the droplet-based approach provides a non-labor intensive and high-throughput means to acquire spatially resolved quantitative analysis of multiple samples of the same type.« less

Extraction efficiency and implications for absolute quantitation of propranolol in mouse brain, liver and kidney thin tissue sections using droplet-based liquid microjunction surface sampling-HPLC ESI-MS/MS

DOE PAGES

Kertesz, Vilmos; Weiskittel, Taylor M.; Vavek, Marissa; ...

2016-06-22

Currently, absolute quantitation aspects of droplet-based surface sampling for thin tissue analysis using a fully automated autosampler/HPLC-ESI-MS/MS system are not fully evaluated. Knowledge of extraction efficiency and its reproducibility is required to judge the potential of the method for absolute quantitation of analytes from thin tissue sections. Methods: Adjacent thin tissue sections of propranolol dosed mouse brain (10- μm-thick), kidney (10- μm-thick) and liver (8-, 10-, 16- and 24- μm-thick) were obtained. Absolute concentration of propranolol was determined in tissue punches from serial sections using standard bulk tissue extraction protocols and subsequent HPLC separations and tandem mass spectrometric analysis. Thesemore » values were used to determine propranolol extraction efficiency from the tissues with the droplet-based surface sampling approach. Results: Extraction efficiency of propranolol using 10- μm-thick brain, kidney and liver thin tissues using droplet-based surface sampling varied between ~45-63%. Extraction efficiency decreased from ~65% to ~36% with liver thickness increasing from 8 μm to 24 μm. Randomly selecting half of the samples as standards, precision and accuracy of propranolol concentrations obtained for the other half of samples as quality control metrics were determined. Resulting precision ( ±15%) and accuracy ( ±3%) values, respectively, were within acceptable limits. In conclusion, comparative quantitation of adjacent mouse thin tissue sections of different organs and of various thicknesses by droplet-based surface sampling and by bulk extraction of tissue punches showed that extraction efficiency was incomplete using the former method, and that it depended on the organ and tissue thickness. However, once extraction efficiency was determined and applied, the droplet-based approach provided the required quantitation accuracy and precision for assay validations. Furthermore, this means that once the extraction efficiency was calibrated for a given tissue type and drug, the droplet-based approach provides a non-labor intensive and high-throughput means to acquire spatially resolved quantitative analysis of multiple samples of the same type.« less

Quantitative study of flavonoids in leaves of citrus plants.

PubMed

Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M; Koizumi, M; Ito, C; Furukawa, H

2000-09-01

Leaf flavonoids were quantitatively determined in 68 representative or economically important Citrus species, cultivars, and near-Citrus relatives. Contents of 23 flavonoids including 6 polymethoxylated flavones were analyzed by means of reversed phase HPLC analysis. Principal component analysis revealed that the 7 associations according to Tanaka's classification were observed, but some do overlap each other. Group VII species could be divided into two different subgroups, namely, the first-10-species class and the last-19-species class according to Tanaka's classification numbers.

Analysis of glycerophosphocholine molecular species as derivatives of 7-[(chlorocarbonyl)-methoxy]-4-methylcoumarin.

PubMed

Wheelan, P; Zirrolli, J A; Clay, K L

1992-01-01

A method has been developed for the analysis of derivatized diradylglycerols obtained from glycerophosphocholine (GPC) of transformed murine bone marrow-derived mast cells that provided high performance liquid chromatography (HPLC) separation of GPC subclasses and molecular species separation with on-line quantitation using UV detection. In addition, the derivatized diradylglycerol species were unequivocably identified by continuous flow fast-atom bombardment mass spectrometry. GPC was initially isolated by thin-layer chromatography (TLC), the phosphocholine group was hydrolyzed, and the resultant diradylglycerol was derivatized with 7-[(chlorocarbonyl)-methoxy]-4-methylcoumarin (CMMC). After separation of the derivatized subclasses by normal phase HPLC, the individual molecular species of the alkylacyl and diacyl subclasses were quantitated and collected during a subsequent reverse phase HPLC step. With an extinction coefficient of 14,700 l mol-1 cm-1 at a wavelength detection of 320 nm, the CMMC derivatives afforded sensitive UV detection (100 pmol) and quantitation of the molecular species. Continuous flow fast-atom bombardment mass spectrometry of the alkylacyl CMMC derivatives yielded abundant [MH]+ ions and a single fragment ion formed by loss of alkylketene from the sn-2 acyl group, [MH-(R = C = O)]+. No fragmentation of the sn-1 alkyl chain was observed. Diacyl derivatives also produced abundant [MH]+ ions plus two fragment ions arising from loss of RCOOH from each of the acyl substituents and two fragment ions from the loss of alkyketene from each acyl group. Individual molecular species substituents were assigned from these ions.

Development and validation of a single robust HPLC method for the characterization of a pharmaceutical starting material and impurities from three suppliers using three separate synthetic routes.

PubMed

Sheldon, E M; Downar, J B

2000-08-15

Novel approaches to the development of analytical procedures for monitoring incoming starting material in support of chemical/pharmaceutical processes are described. High technology solutions were utilized for timely process development and preparation of high quality clinical supplies. A single robust HPLC method was developed and characterized for the analysis of the key starting material from three suppliers. Each supplier used a different process for the preparation of this material and, therefore, each suppliers' material exhibited a unique impurity profile. The HPLC method utilized standard techniques acceptable for release testing in a QC/manufacturing environment. An automated experimental design protocol was used to characterize the robustness of the HPLC method. The method was evaluated for linearity, limit of quantitation, solution stability, and precision of replicate injections. An LC-MS method that emulated the release HPLC method was developed and the identities of impurities were mapped between the two methods.

Linear regression analysis and its application to multivariate chromatographic calibration for the quantitative analysis of two-component mixtures.

PubMed

Dinç, Erdal; Ozdemir, Abdil

2005-01-01

Multivariate chromatographic calibration technique was developed for the quantitative analysis of binary mixtures enalapril maleate (EA) and hydrochlorothiazide (HCT) in tablets in the presence of losartan potassium (LST). The mathematical algorithm of multivariate chromatographic calibration technique is based on the use of the linear regression equations constructed using relationship between concentration and peak area at the five-wavelength set. The algorithm of this mathematical calibration model having a simple mathematical content was briefly described. This approach is a powerful mathematical tool for an optimum chromatographic multivariate calibration and elimination of fluctuations coming from instrumental and experimental conditions. This multivariate chromatographic calibration contains reduction of multivariate linear regression functions to univariate data set. The validation of model was carried out by analyzing various synthetic binary mixtures and using the standard addition technique. Developed calibration technique was applied to the analysis of the real pharmaceutical tablets containing EA and HCT. The obtained results were compared with those obtained by classical HPLC method. It was observed that the proposed multivariate chromatographic calibration gives better results than classical HPLC.

[Bioactive saponins and glycosides. XIII. Horse chestnut. (3): Quantitative analysis of escins Ia, Ib, IIa, and IIb by means of high performance liquid chromatography].

PubMed

Yoshikawa, M; Murakami, T; Otuki, K; Yamahara, J; Matsuda, H

1999-01-01

As a part of our studies on the characterization of bioactive saponin constituents of horse chestnut trees, a quantitative method using high performance liquid chromatography (HPLC) has been developed for four principle saponin constituents, such as escins Ia, Ib, IIa, and IIb, isolated from the seeds of European horse chestnut trees (Aesculus hippocastanum L., Hippocastanaceae). As an application of this HPLC method, we examined the contents and compositions of these escins in the seeds of Japanese horse chestnut trees (A. turbinata BLUME) and in several commercial materials named as "beta-escin". Additionally, the distribution of escins in the Japanese horse chestnut trees was examined, and escins were found to be contained only in the seeds.

Quantitative Analysis and Comparison of Four Major Flavonol Glycosides in the Leaves of Toona sinensis (A. Juss.) Roemer (Chinese Toon) from Various Origins by High-Performance Liquid Chromatography-Diode Array Detector and Hierarchical Clustering Analysis

PubMed Central

Sun, Xiaoxiang; Zhang, Liting; Cao, Yaqi; Gu, Qinying; Yang, Huan; Tam, James P.

2016-01-01

Background: Toona sinensis (A. Juss.) Roemer is an endemic species of Toona genus native to Asian area. Its dried leaves are applied in the treatment of many diseases; however, few investigations have been reported for the quantitative analysis and comparison of major bioactive flavonol glycosides in the leaves harvested from various origins. Objective: To quantitatively analyze four major flavonol glycosides including rutinoside, quercetin-3-O-β-D-glucoside, quercetin-3-O-α-L-rhamnoside, and kaempferol-3-O-α-L-rhamnoside in the leaves from different production sites and classify them according to the content of these glycosides. Materials and Methods: A high-performance liquid chromatography-diode array detector (HPLC-DAD) method for their simultaneous determination was developed and validated for linearity, precision, accuracy, stability, and repeatability. Moreover, the method established was then employed to explore the difference in the content of these four glycosides in raw materials. Finally, a hierarchical clustering analysis was performed to classify 11 voucher specimens. Results: The separation was performed on a Waters XBridge Shield RP18 column (150 mm × 4.6 mm, 3.5 μm) kept at 35°C, and acetonitrile and H2O containing 0.30% trifluoroacetic acid as mobile phase was driven at 1.0 mL/min during the analysis. Ten microliters of solution were injected and 254 nm was selected to monitor the separation. A strong linear relationship between the peak area and concentration of four analytes was observed. And, the method was also validated to be repeatable, stable, precise, and accurate. Conclusion: An efficient and reliable HPLC-DAD method was established and applied in the assays for the samples from 11 origins successfully. Moreover, the content of those flavonol glycosides varied much among different batches, and the flavonoids could be considered as biomarkers to control the quality of Chinese Toon. SUMMARY Four major flavonol glycosides in the leaves of Toona sinensis were determined by HPLC-DAD and their contents were compared among various origins by HCA. Abbreviations used: HPLC-DAD: High-performance liquid chromatography-diode array detector, HCA: Hierarchical clustering analysis, MS: Mass spectrometry, RSD: Relative standard deviation. PMID:27279719

[Functional saponins in tea flower (flower buds of Camellia sinensis): gastroprotective and hypoglycemic effects of floratheasaponins and qualitative and quantitative analysis using HPLC].

PubMed

Yoshikawa, Masayuki; Wang, Tao; Sugimoto, Sachiko; Nakamura, Seikou; Nagatomo, Akifumi; Matsuda, Hisashi; Harima, Shoichi

2008-01-01

As a part of our characterization studies on the bioactive saponin constituents of tea flowers (Camellia sinensis, flower buds), the methanolic extract and 1-butanol-soluble portion (the saponin fraction) from the flower buds were found to exhibit potent inhibitory effects on ethanol- and indomethacin-induced gastric mucosal lesions in rats and on serum glucose elevation in sucrose-loaded rats. Among the constituents of the 1-butanol-soluble portion, floratheasaponins A, B, and C showed gastroprotective and hypoglycemic activities. Furthermore, we have developed qualitative and quantitative methods using HPLC for the principle saponins, floratheasaponins A-F, in tea flowers, which were previously found to show antiallergic and antiobesity effects. Using those methods, the saponin composition of Indian tea flowers were found to be similar to those of Chinese (Anhui) but not of Japanese tea flowers. On the other hand, it was found that the floratheasaponin contents in tea flowers varied markedly during the blooming period, and they were abundant at half-bloom. Additionally, the contents of caffeine in the tea flowers were examined using HPLC.

Quality evaluation and pattern recognition analyses of marker compounds from five medicinal drugs of Rutaceae family by HPLC/PDA.

PubMed

Zhao, Bing Tian; Kim, Eun Jung; Son, Kun Ho; Son, Jong Keun; Min, Byung Sun; Woo, Mi Hee

2015-08-01

To establish a standard of quality control and to identify different origins for the Rutaceae family [Citri Unshiu Peel (CU), Citri Unshiu Immature Peel (CI), Ponciri Immature Fructus (PI), Aurantii Immature Fructus (AI), and Aurantii Fructus (AU)], 13 standards including rutin (1), narirutin (2), naringin (3), hesperidin (4), neohesperidin (5), neoponcirin (6), poncirin (7), naringenin (8), isosinensetin (9), sinensetin (10), nobiletin (11), heptamethoxyflavone (12), and tangeretin (13) were determined by high performance liquid chromatography (HPLC)/photo-diode array (PDA) analysis. A YMC ODS C18 (250 × 4.6 mm, 5 µm) column was used and the ratio of mobile phases of water (A) and acetonitrile (B) delivered to the column for gradient elution was applied. This method was fully validated with respect to linearity, accuracy, precision, stability, and robustness. The HPLC/PDA method was applied successfully to quantify 13 major compounds in the extracts of CU, CI, PI, AI, and AU. The pattern recognition analysis combined with LC chromatographic data was performed by repeated analysis of 27 reference samples in the above five Rutaceae oriental medicinal drugs. The established HPLC method was rapid and reliable for quantitative analysis and quality control of multiple components in five Rutaceae species with different origins.

Improved hydrophilic interaction chromatography LC/MS of heparinoids using a chip with postcolumn makeup flow.

PubMed

Staples, Gregory O; Naimy, Hicham; Yin, Hongfeng; Kileen, Kevin; Kraiczek, Karsten; Costello, Catherine E; Zaia, Joseph

2010-01-15

Heparan sulfate (HS) and heparin are linear, heterogeneous carbohydrates of the glycosaminoglycan (GAG) family that are modified by N-acetylation, N-sulfation, O-sulfation, and uronic acid epimerization. HS interacts with growth factors in the extracellular matrix, thereby modulating signaling pathways that govern cell growth, development, differentiation, proliferation, and adhesion. High-performance liquid chromatography (HPLC)-chip-based hydrophilic interaction liquid chromatography/mass spectrometry has emerged as a method for analyzing the domain structure of GAGs. However, analysis of highly sulfated GAG structures decasaccharide or larger in size has been limited by spray instability in the negative-ion mode. This report demonstrates that addition of postcolumn makeup flow to the amide-HPLC-chip configuration permits robust and reproducible analysis of extended GAG domains (up to degree of polymerization 18) from HS and heparin. This platform provides quantitative information regarding the oligosaccharide profile, degree of sulfation, and nonreducing chain termini. It is expected that this technology will enable quantitative, comparative glycomics profiling of extended GAG oligosaccharide domains of functional interest.

Quantitative HPLC Analysis of an Analgesic/Caffeine Formulation: Determination of Caffeine

NASA Astrophysics Data System (ADS)

Ferguson, Glenda K.

1998-04-01

A modern high performance liquid chromatography (HPLC) laboratory experiment which entails the separation of acetaminophen, aspirin, and caffeine and the quantitative assay of caffeine in commercial mixtures of these compounds has been developed. Our HPLC protocol resolves these compounds in only three minutes with a straightforward chromatographic apparatus which consists of a C-18 column, an isocratic mobile phase, UV detection at 254 nm, and an integrator; an expensive, sophisticated system is not required. The separation is both repeatable and rapid. Moreover, the experiment can be completed in a single three-hour period. The experiment is appropriate for any chemistry student who has completed a minimum of one year of general chemistry and is ideal for an analytical or instrumental analysis course. The experiment detailed herein involves the determination of caffeine in Goody's Extra Strength Headache Powders, a commercially available medication which contains acetaminophen, aspirin, and caffeine as active ingredients. However, the separation scheme is not limited to this brand of medication nor is it limited to caffeine as the analyte. With only minor procedural modifications, students can simultaneously quantitate all of these compounds in a commercial mixture. In our procedure, students prepare a series of four caffeine standard solutions as well as a solution from a pharmaceutical analgesic/caffeine mixture, chromatographically analyze each solution in quadruplicate, and plot relative average caffeine standard peak area versus concentration. From the mathematical relationship that results, the concentration of caffeine in the commercial formulation is obtained. Finally, the absolute standard deviation of the mean concentration is calculated.

Oxalic Acid from Lentinula edodes Culture Filtrate: Antimicrobial Activity on Phytopathogenic Bacteria and Qualitative and Quantitative Analyses

PubMed Central

Kwak, A-Min; Lee, In-Kyoung; Lee, Sang-Yeop

2016-01-01

The culture filtrate of Lentinula edodes shows potent antimicrobial activity against the plant pathogenic bacteria Ralstonia solanacearum. Bioassay-guided fractionation was conducted using Diaion HP-20 column chromatography, and the insoluble active compound was not adsorbed on the resin. Further fractionation by high-performance liquid chromatography (HPLC) suggested that the active compounds were organic acids. Nine organic acids were detected in the culture filtrate of L. edodes; oxalic acid was the major component and exhibited antibacterial activity against nine different phytopathogenic bacteria. Quantitative analysis by HPLC revealed that the content of oxalic acid was higher in the water extract from spent mushroom substrate than in liquid culture. This suggests that the water extract of spent L. edodes substrate is an eco-friendly control agent for plant diseases. PMID:28154495

Determination of chloroacetanilide herbicide metabolites in water using high-performance liquid chromatography-diode array detection and high-performance liquid chromatography/mass spectrometry

USGS Publications Warehouse

Hostetler, K.A.; Thurman, E.M.

2000-01-01

Analytical methods using high-performance liquid chromatography-diode array detection (HPLC-DAD) and high-performance liquid chromatography/mass spectrometry (HPLC/MS) were developed for the analysis of the following chloroacetanilide herbicide metabolites in water: alachlor ethanesulfonic acid (ESA); alachlor oxanilic acid; acetochlor ESA; acetochlor oxanilic acid; metolachlor ESA; and metolachlor oxanilic acid. Good precision and accuracy were demonstrated for both the HPLC-DAD and HPLC/MS methods in reagent water, surface water, and ground water. The average HPLC-DAD recoveries of the chloroacetanilide herbicide metabolites from water samples spiked at 0.25, 0.5 and 2.0 ??g/l ranged from 84 to 112%, with relative standard deviations of 18% or less. The average HPLC/MS recoveries of the metabolites from water samples spiked at 0.05, 0.2 and 2.0 ??g/l ranged from 81 to 118%, with relative standard deviations of 20% or less. The limit of quantitation (LOQ) for all metabolites using the HPLC-DAD method was 0.20 ??g/l, whereas the LOQ using the HPLC/MS method was at 0.05 ??g/l. These metabolite-determination methods are valuable for acquiring information about water quality and the fate and transport of the parent chloroacetanilide herbicides in water. Copyright (C) 2000 Elsevier Science B.V.

Extraction and HPLC- UV Analysis of C60, C70, and [6,6]-phenyl C61-butyric acid methyl ester in Synthetic and Natural Waters

EPA Science Inventory

Studies have shown that C60 fullerene can form stable colloidal suspensions in water that result in C60 aqueous concentrations many orders of magnitude above C60's aqueous solubility; however, quantitative methods for the analysis of C60 and other fullerenes in environmental medi...

Quantification of appetite suppressing steroid glycosides from Hoodia gordonii in dried plant material, purified extracts and food products using HPLC-UV and HPLC-MS methods.

PubMed

Janssen, Hans-Gerd; Swindells, Chris; Gunning, Philip; Wang, Weijun; Grün, Christian; Mahabir, Krishna; Maharaj, Vinesh J; Apps, Peter J

2008-06-09

High-performance liquid chromatography (HPLC)-UV and HPLC-Mass Spectrometry (MS) methods were developed for the quantitative analysis of the family of Hoodia gordonii steroid glycosides with appetite suppressing properties in dried plant material, in purified and enriched extracts and in various prototype food-products fortified with H. gordonii extracts. For solid materials, e.g. dried plants or for non-fatty foods, extraction of the steroid glycosides is performed using methanol. For products where the steroid glycosides are present in an oil matrix, direct injection of the oil after dilution in tetrahydrofuran is applied. The HPLC separation is performed on an octyl-modified reversed-phase column in the gradient mode with UV detection at lambda = 220 nm. Quantification is performed against an external calibration line prepared using either one of the pure steroid glycosides or geranyl-tiglate. Short- and long-term repeatabilities of the methods are better than 3 and 6%, respectively. Recoveries are better than 85%, even in the analysis of the least abundant steroid glycosides in a complex yoghurt drink. Linearity is better than 3-4 orders of magnitude and the detection limits are below approximately 2 microg g(-1) for the individual steroid glycosides in dried plant material and food products. HPLC-MS is used to confirm that the steroid glycosides contain the characteristic steroid core, the carbohydrate chain and the tigloyl group.

Quality Evaluation of Potentilla fruticosa L. by High Performance Liquid Chromatography Fingerprinting Associated with Chemometric Methods.

PubMed

Liu, Wei; Wang, Dongmei; Liu, Jianjun; Li, Dengwu; Yin, Dongxue

2016-01-01

The present study was performed to assess the quality of Potentilla fruticosa L. sampled from distinct regions of China using high performance liquid chromatography (HPLC) fingerprinting coupled with a suite of chemometric methods. For this quantitative analysis, the main active phytochemical compositions and the antioxidant activity in P. fruticosa were also investigated. Considering the high percentages and antioxidant activities of phytochemicals, P. fruticosa samples from Kangding, Sichuan were selected as the most valuable raw materials. Similarity analysis (SA) of HPLC fingerprints, hierarchical cluster analysis (HCA), principle component analysis (PCA), and discriminant analysis (DA) were further employed to provide accurate classification and quality estimates of P. fruticosa. Two principal components (PCs) were collected by PCA. PC1 separated samples from Kangding, Sichuan, capturing 57.64% of the variance, whereas PC2 contributed to further separation, capturing 18.97% of the variance. Two kinds of discriminant functions with a 100% discrimination ratio were constructed. The results strongly supported the conclusion that the eight samples from different regions were clustered into three major groups, corresponding with their morphological classification, for which HPLC analysis confirmed the considerable variation in phytochemical compositions and that P. fruticosa samples from Kangding, Sichuan were of high quality. The results of SA, HCA, PCA, and DA were in agreement and performed well for the quality assessment of P. fruticosa. Consequently, HPLC fingerprinting coupled with chemometric techniques provides a highly flexible and reliable method for the quality evaluation of traditional Chinese medicines.

Quality Evaluation of Potentilla fruticosa L. by High Performance Liquid Chromatography Fingerprinting Associated with Chemometric Methods

PubMed Central

Liu, Wei; Wang, Dongmei; Liu, Jianjun; Li, Dengwu; Yin, Dongxue

2016-01-01

The present study was performed to assess the quality of Potentilla fruticosa L. sampled from distinct regions of China using high performance liquid chromatography (HPLC) fingerprinting coupled with a suite of chemometric methods. For this quantitative analysis, the main active phytochemical compositions and the antioxidant activity in P. fruticosa were also investigated. Considering the high percentages and antioxidant activities of phytochemicals, P. fruticosa samples from Kangding, Sichuan were selected as the most valuable raw materials. Similarity analysis (SA) of HPLC fingerprints, hierarchical cluster analysis (HCA), principle component analysis (PCA), and discriminant analysis (DA) were further employed to provide accurate classification and quality estimates of P. fruticosa. Two principal components (PCs) were collected by PCA. PC1 separated samples from Kangding, Sichuan, capturing 57.64% of the variance, whereas PC2 contributed to further separation, capturing 18.97% of the variance. Two kinds of discriminant functions with a 100% discrimination ratio were constructed. The results strongly supported the conclusion that the eight samples from different regions were clustered into three major groups, corresponding with their morphological classification, for which HPLC analysis confirmed the considerable variation in phytochemical compositions and that P. fruticosa samples from Kangding, Sichuan were of high quality. The results of SA, HCA, PCA, and DA were in agreement and performed well for the quality assessment of P. fruticosa. Consequently, HPLC fingerprinting coupled with chemometric techniques provides a highly flexible and reliable method for the quality evaluation of traditional Chinese medicines. PMID:26890416

Quantitative HPLC Analysis of a Psychotherapeutic Medication: Simultaneous Determination of Amitriptyline Hydrochloride and Perphenazine

NASA Astrophysics Data System (ADS)

Ferguson, Glenda K.

1998-12-01

A quantitative high-performance liquid chromatography (HPLC) laboratory experiment which entails the isocratic separation and simultaneous determination of the two active components of a commercial antipsychotic tablet has been developed. The prescription formulation used in this experiment contains amitriptyline hydrochloride (a tricyclic antidepressant) and perphenazine (a tranquilizer). Our experiment makes use of a straightforward HPLC separation on a cyanopropyl-packed column with an acetonitrile:methanol:aqueous monopotassium phosphate mobile phase pumped at a flow rate of 2.0 mL/min. Analytes are detected by UV absorbance at 215 nm. These conditions yield highly symmetrical and well-resolved peaks in less than 5 min after the injection of a mixture. In the experiment, students are given amitriptyline hydrochloride-perphenazine tablets without the manufacturer's labeled composition claim and a stock solution mixture with known concentrations of amitriptyline hydrochloride and perphenazine. They prepare four standards and a pharmaceutical sample of unknown concentration, assay each solution in quadruplicate, and plot average peak areas of the concentrations of the known solutions in the construction of a standard curve. From the mathematical relationships that result, the average masses of amitriptyline hydrochloride and perphenazine in the prescription tablet are determined. Finally, the standard deviations of the mean masses are calculated. The entire laboratory procedure and statistical data analysis can be completed in a single 3-hour period.

Application of solid-phase microextraction in the investigation of protein binding of pharmaceuticals.

PubMed

Theodoridis, Georgios

2006-01-18

Protein-drug interactions of seven common pharmaceuticals were studied using solid-phase microextraction (SPME). SPME can be used in such investigations on the condition that no analyte depletion occurs. In multi-compartment systems (e.g. a proteinaceous matrix) only the free portion of the analyte is able to partition into the SPME fiber. In addition if no sample depletion occurs, the bound drug-free drug equilibria are not disturbed. In the present study seven pharmaceuticals (quinine, quinidine, naproxen, ciprofloxacin, haloperidol, paclitaxel and nortriptyline) were assayed by SPME. For quantitative purposes SPME was validated first in the absence of proteins. Calibration curves were constructed for each drug by HPLC-fluorescence and HPLC-UV analysis. SPME was combined to HPLC off-line, desorption occurring in HPLC inserts filled with 200 microL methanol. Binding of each drug to human serum albumin was studied independently. Experimental results were in agreement with literature data and ultrafiltration experiments, indicating the feasibility of the method for such bioanalytical purposes.

Analysis of condensed and hydrolysable tannins from commercial plant extracts.

PubMed

Romani, A; Ieri, F; Turchetti, B; Mulinacci, N; Vincieri, F F; Buzzini, P

2006-05-03

High performance liquid chromatography (HPLC)/DAD and MS qualitative and quantitative analyses of polyphenols, hydrolysable and condensed tannins from Pinus maritima L. and tannic acid (TA) extracts were performed using normal and reverse phase. Normal-phase HPLC was more suitable for pine bark (PBE) and tannic acid extracts analysis. The chromatographic profile revealed that P. maritima L. extract was mainly composed by polymeric flavanols (containing from two to seven units) and tannic acid (characterized by a mixture of glucose gallates containing from three to seven units of gallic acid). Concerning their antimycotic properties, P. maritima L. extract exhibited a broad activity towards yeast strains of the genera Candida, Cryptococcus, Filobasidiella, Issatchenkia, Saccharomyces: MICs from 200 to 4000 microg/ml (corresponding to 140-2800 microg/ml of active polyphenols) were determined. Conversely, no activity of tannic acid was observed over the same target microorganisms. Taken into consideration the above results of HPLC analysis and on the basis of the current literature, we may conclude that only 70.2% of polyphenols (recognized as condensed tannins) occurring in P. maritima L. extract can be apparently considered responsible for its antimycotic activity.

Separating DDTs in edible animal fats using matrix solid-phase dispersion extraction with activated carbon filter, Toyobo-KF.

PubMed

Furusawa, Naoto

2006-09-01

A technique is presented for the economical, routine, and quantitative analysis of contamination by dichloro-diphenyl-trichloroethanes (DDTs) [pp'-DDT, pp'-dichlorodiphenyl dichloroethylene, and pp'-dichlorodiphenyl dichloreothane in beef tallow and chicken fat samples, based on their separation using matrix solid-phase dispersion (MSPD) extraction with Toyobo-KF, an activated carbon fiber. Toyobo-KF is a newly applied MSPD sorbent, and it is followed by reversed-phase high-performance liquid chromatography (HPLC) with a photodiode array detector. The resulting analytical performance parameters [recoveries of spiked DDTs (0.1, 0.2, and 0.4 microg/g) > or = 81%, with relative standard deviations of < or = 8% (n = 5), and quantitation limits < or = 0.03 microg/g], with minimal handling and cost-efficiency, indicate that the present MSPD-HPLC method may be a useful tool for routine monitoring of DDT contamination in meat.

Quantitative and Qualitative Determination of Polysulfide Species in the Electrolyte of a Lithium-Sulfur Battery using HPLC ESI/MS with One-Step Derivatization

DOE PAGES

Zheng, Dong; Qu, Deyu; Yang, Xiao-Qing; ...

2015-01-29

The polysulfide species dissolved in aprotic solvents can be separated and analyzed by reverse phase (RP) high performance liquid chromatography (HPLC) in tandem with electrospray-mass spectroscopy. The relative distribution of polysulfide species in the electrolyte recovered from Li-S batteries is quantitatively and reliably determined for the first time.

Quantitative and Qualitative Determination of Polysulfide Species in the Electrolyte of a Lithium-Sulfur Battery using HPLC ESI/MS with One-Step Derivatization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, Dong; Qu, Deyu; Yang, Xiao-Qing

The polysulfide species dissolved in aprotic solvents can be separated and analyzed by reverse phase (RP) high performance liquid chromatography (HPLC) in tandem with electrospray-mass spectroscopy. The relative distribution of polysulfide species in the electrolyte recovered from Li-S batteries is quantitatively and reliably determined for the first time.

Ion chromatography for the precise analysis of chloride and sodium in sweat for the diagnosis of cystic fibrosis.

PubMed

Doorn, J; Storteboom, T T R; Mulder, A M; de Jong, W H A; Rottier, B L; Kema, I P

2015-07-01

Measurement of chloride in sweat is an essential part of the diagnostic algorithm for cystic fibrosis. The lack in sensitivity and reproducibility of current methods led us to develop an ion chromatography/high-performance liquid chromatography (IC/HPLC) method, suitable for the analysis of both chloride and sodium in small volumes of sweat. Precision, linearity and limit of detection of an in-house developed IC/HPLC method were established. Method comparison between the newly developed IC/HPLC method and the traditional Chlorocounter was performed, and trueness was determined using Passing Bablok method comparison with external quality assurance material (Royal College of Pathologists of Australasia). Precision and linearity fulfill criteria as established by UK guidelines are comparable with inductively coupled plasma-mass spectrometry methods. Passing Bablok analysis demonstrated excellent correlation between IC/HPLC measurements and external quality assessment target values, for both chloride and sodium. With a limit of quantitation of 0.95 mmol/L, our method is suitable for the analysis of small amounts of sweat and can thus be used in combination with the Macroduct collection system. Although a chromatographic application results in a somewhat more expensive test compared to a Chlorocounter test, more accurate measurements are achieved. In addition, simultaneous measurements of sodium concentrations will result in better detection of false positives, less test repeating and thus faster and more accurate and effective diagnosis. The described IC/HPLC method, therefore, provides a precise, relatively cheap and easy-to-handle application for the analysis of both chloride and sodium in sweat. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Characterization of the isomeric configuration and impurities of (Z)-endoxifen by 2D NMR, high resolution LC⬜MS, and quantitative HPLC analysis.

PubMed

Elkins, Phyllis; Coleman, Donna; Burgess, Jason; Gardner, Michael; Hines, John; Scott, Brendan; Kroenke, Michelle; Larson, Jami; Lightner, Melissa; Turner, Gregory; White, Jonathan; Liu, Paul

2014-01-01

(Z)-Endoxifen (4-hydroxy-N-desmethyltamoxifen), an active metabolite generated via actions of CYP3A4/5 and CYP2D6, is a more potent selective estrogen receptor modulator (SERM) than tamoxifen. In the MCF-7 human mammary tumor xenograft model with female athymic mice, (Z)-endoxifen, at an oral dose of 4⬜8 mg/kg, significantly inhibits tumor growth. (Z)-Endoxifen's potential as an alternative therapeutic agent independent of CYP2D6 activities, which can vary widely in ER+ breast cancer patients, is being actively evaluated. This paper describes confirmation of the configuration of the active (Z)-isomer through 2D NMR experiments, including NOE (ROESY) to establish spatial proton⬜proton correlations, and identification of the major impurity as the (E)-isomer in endoxifen drug substance by HPLC/HRMS (HPLC/MS-TOF). Stability of NMR solutions was confirmed by HPLC/UV analysis. For pre-clinical studies, a reverse-phase HPLC⬜UV method, with methanol/water mobile phases containing 10 mM ammonium formate at pH 4.3, was developed and validated for the accurate quantitation and impurity profiling of drug substance and drug product. Validation included demonstration of linearity, method precision, accuracy, and specificity in the presence of impurities, excipients (for the drug product), and degradation products. Ruggedness and reproducibility of the method were confirmed by collaborative studies between two independent laboratories. The method is being applied for quality control of the API and oral drug product. Kinetic parameters of Z- to E-isomerization were also delineated in drug substance and in aqueous formulation, showing conversion at temperatures above 25 °C. Copyright © 2014 Elsevier B.V. All rights reserved.

The Second SeaWiFS HPLC Analysis Round-Robin Experiment (SeaHARRE-2)

NASA Technical Reports Server (NTRS)

2005-01-01

Eight international laboratories specializing in the determination of marine pigment concentrations using high performance liquid chromatography (HPLC) were intercompared using in situ samples and a variety of laboratory standards. The field samples were collected primarily from eutrophic waters, although mesotrophic waters were also sampled to create a dynamic range in chlorophyll concentration spanning approximately two orders of magnitude (0.3 25.8 mg m-3). The intercomparisons were used to establish the following: a) the uncertainties in quantitating individual pigments and higher-order variables (sums, ratios, and indices); b) an evaluation of spectrophotometric versus HPLC uncertainties in the determination of total chlorophyll a; and c) the reduction in uncertainties as a result of applying quality assurance (QA) procedures associated with extraction, separation, injection, degradation, detection, calibration, and reporting (particularly limits of detection and quantitation). In addition, the remote sensing requirements for the in situ determination of total chlorophyll a were investigated to determine whether or not the average uncertainty for this measurement is being satisfied. The culmination of the activity was a validation of the round-robin methodology plus the development of the requirements for validating an individual HPLC method. The validation process includes the measurements required to initially demonstrate a pigment is validated, and the measurements that must be made during sample analysis to confirm a method remains validated. The so-called performance-based metrics developed here describe a set of thresholds for a variety of easily-measured parameters with a corresponding set of performance categories. The aggregate set of performance parameters and categories establish a) the overall performance capability of the method, and b) whether or not the capability is consistent with the required accuracy objectives.

Development and comparison of HPLC-MS/MS and UPLC-MS/MS methods for determining eight coccidiostats in beef.

PubMed

Zhao, Xia; Wang, Bo; Xie, Kaizhou; Liu, Jianyu; Zhang, Yangyang; Wang, Yajuan; Guo, Yawen; Zhang, Genxi; Dai, Guojun; Wang, Jinyu

2018-06-15

A high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method and an ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for determining eight coccidiostat (halofuginone, lasalocid, maduramicin, monensin, narasin, nigericin, robenidine and salinomycin) residues in beef were developed and compared. Samples were extracted with a mixture of acetic acid, acetonitrile and ethyl acetate and were then purified on a C 18 solid-phase extraction (SPE) column. The purified samples were analyzed by HPLC-MS/MS and UPLC-MS/MS, using 0.1% formic acid-water solution (A) and pure methanol (B) as the mobile phase. The samples were fractionated on a C 18 column using different gradient elution procedures, followed by qualitative analysis using a mass spectrometer operated in multiple reaction monitoring (MRM) mode with positive electrospray ionization; the external standard method was used for quantitation. At spiked levels that ranged from the limit of quantification (LOQ) to 100 μg/kg, the average recoveries were 71.96%-100.32% and 71.24%-89.24%, with relative standard deviations (RSDs) of 2.65%-12.38% and 2.98%-14.86% for UPLC-MS/MS and HPLC-MS/MS, respectively. The limits of detection (LODs) and LOQs of the eight coccidiostats were 0.14-0.32 μg/kg and 0.43-1.21 μg/kg, respectively, for UPLC-MS/MS analysis and 0.16-0.58 μg/kg and 0.53-1.92 μg/kg, respectively, for HPLC-MS/MS analysis. Both methods had good accuracy and precision, but UPLC-MS/MS had higher sensitivity than HPLC-MS/MS. Copyright © 2018 Elsevier B.V. All rights reserved.

High-throughput quantitation of amino acids in rat and mouse biological matrices using stable isotope labeling and UPLC-MS/MS analysis.

PubMed

Takach, Edward; O'Shea, Thomas; Liu, Hanlan

2014-08-01

Quantifying amino acids in biological matrices is typically performed using liquid chromatography (LC) coupled with fluorescent detection (FLD), requiring both derivatization and complete baseline separation of all amino acids. Due to its high specificity and sensitivity, the use of UPLC-MS/MS eliminates the derivatization step and allows for overlapping amino acid retention times thereby shortening the analysis time. Furthermore, combining UPLC-MS/MS with stable isotope labeling (e.g., isobaric tag for relative and absolute quantitation, i.e., iTRAQ) of amino acids enables quantitation while maintaining sensitivity, selectivity and speed of analysis. In this study, we report combining UPLC-MS/MS analysis with iTRAQ labeling of amino acids resulting in the elution and quantitation of 44 amino acids within 5 min demonstrating the speed and convenience of this assay over established approaches. This chromatographic analysis time represented a 5-fold improvement over the conventional HPLC-MS/MS method developed in our laboratory. In addition, the UPLC-MS/MS method demonstrated improvements in both specificity and sensitivity without loss of precision. In comparing UPLC-MS/MS and HPLC-MS/MS results of 32 detected amino acids, only 2 amino acids exhibited imprecision (RSD) >15% using UPLC-MS/MS, while 9 amino acids exhibited RSD >15% using HPLC-MS/MS. Evaluating intra- and inter-assay precision over 3 days, the quantitation range for 32 detected amino acids in rat plasma was 0.90-497 μM, with overall mean intra-day precision of less than 15% and mean inter-day precision of 12%. This UPLC-MS/MS assay was successfully implemented for the quantitative analysis of amino acids in rat and mouse plasma, along with mouse urine and tissue samples, resulting in the following concentration ranges: 0.98-431 μM in mouse plasma for 32 detected amino acids; 0.62-443 μM in rat plasma for 32 detected amino acids; 0.44-8590μM in mouse liver for 33 detected amino acids; 0.61-1241 μM in mouse kidney for 37 detected amino acids; and 1.39-1,681 μM in rat urine for 34 detected amino acids. The utility of the assay was further demonstrated by measuring and comparing plasma amino acid levels between pre-diabetic Zucker diabetic fatty rats (ZDF/Gmi fa/fa) and their lean littermates (ZDF/Gmi fa/?). Significant differences (P<0.001) in 9 amino acid concentrations were observed, with the majority ranging from a 2- to 5-fold increase in pre-diabetic ZDF rats on comparison with ZDF lean rats, consistent with previous literature reports. Copyright © 2014 Elsevier B.V. All rights reserved.

Microwave-assisted extraction with water for fast extraction and simultaneous RP-HPLC determination of phenolic acids in radix Salviae Miltiorrhizae.

PubMed

Fang, Xinsheng; Wang, Jianhua; Zhou, Hongying; Jiang, Xingkai; Zhu, Lixiang; Gao, Xin

2009-07-01

An optimized microwave-assisted extraction method using water (MAE-W) as the extractant and an efficient HPLC analysis method were first developed for the fast extraction and simultaneous determination of D(+)-(3,4-dihydroxyphenyl) lactic acid (Dla), salvianolic acid B (SaB), and lithospermic acid (La) in radix Salviae Miltiorrhizae. The key parameters of MAE-W were optimized. It was found that the degradation of SaB was inhibited when using the optimized MAE-W and the stable content of Dla, La, and SaB in danshen was obtained. Furthermore, compared to the conventional extraction methods, the proposed MAE-W is a more rapid method with higher yield and lower solvent consumption with a reproducibility (RSD <6%). In addition, using water as extractant is safe and helpful for environment protection, which could be referred to as green extraction. The separation and quantitative determination of the three compounds was carried out by a developed reverse-phase high-performance liquid chromatographic (RP-HPLC) method with UV detection. Highly efficient separation was obtained using gradient solvent system. The optimized HPLC analysis method was validated to have specificity, linearity, precision, and accuracy. The results indicated that MAE-W followed by HPLC-UV determination is an appropriate alternative to previously proposed method for quality control of radix Salviae Miltiorrhizae.

[Quality evaluation of Artemisiae Argyi Folium based on fingerprint analysis and quantitative analysis of multicomponents].

PubMed

Guo, Long; Jiao, Qian; Zhang, Dan; Liu, Ai-Peng; Wang, Qian; Zheng, Yu-Guang

2018-03-01

Artemisiae Argyi Folium, the dried leaves of Artemisia argyi, has been widely used in traditional Chinese and folk medicines for treatment of hemorrhage, pain, and skin itch. Phytochemical studies indicated that volatile oil, organic acid and flavonoids were the main bioactive components in Artemisiae Argyi Folium. Compared to the volatile compounds, the research of nonvolatile compounds in Artemisiae Argyi Folium are limited. In the present study, an accurate and reliable fingerprint approach was developed using HPLC for quality control of Artemisiae Argyi Folium. A total of 10 common peaks were marked，and the similarity of all the Artemisiae Argyi Folium samples was above 0.940. The established fingerprint method could be used for quality control of Artemisiae Argyi Folium. Furthermore, an HPLC method was applied for simultaneous determination of seven bioactive compounds including five organic acids and two flavonoids in Artemisiae Argyi Folium and Artemisiae Lavandulaefoliae Folium samples. Moreover, chemometrics methods such as hierarchical clustering analysis and principal component analysis were performed to compare and discriminate the Artemisiae Argyi Folium and Artemisiae Lavandulaefoliae Folium based on the quantitative data of analytes. The results indicated that simultaneous quantification of multicomponents coupled with chemometrics analysis could be a well-acceptable strategy to identify and evaluate the quality of Artemisiae Argyi Folium. Copyright© by the Chinese Pharmaceutical Association.

[HPLC fingerprint of flavonoids in Sophora flavescens and determination of five components].

PubMed

Ma, Hong-Yan; Zhou, Wan-Shan; Chu, Fu-Jiang; Wang, Dong; Liang, Sheng-Wang; Li, Shao

2013-08-01

A simple and reliable method of high-performance liquid chromatography with photodiode array detection (HPLC-DAD) was developed to evaluate the quality of a traditional Chinese medicine Sophora flavescens through establishing chromatographic fingerprint and simultaneous determination of five flavonoids, including trifolirhizin, maackiain, kushenol I, kurarinone and sophoraflavanone G. The optimal conditions of separation and detection were achieved on an ULTIMATE XB-C18 column (4.6 mm x 250 mm, 5 microm) with a gradient of acetonitrile and water, detected at 295 nm. In the chromatographic fingerprint, 13 peaks were selected as the characteristic peaks to assess the similarities of different samples collected from different origins in China according to similarity evaluation for chromatographic fingerprint of traditional chinese medicine (2004AB) and principal component analysis (PCA) were used in data analysis. There were significant differences in the fingerprint chromatograms between S. flavescens and S. tonkinensis. Principal component analysis showed that kurarinone and sophoraflavanone G were the most important component. In quantitative analysis, the five components showed good regression (R > 0.999) with linear ranges, and their recoveries were in the range of 96.3% - 102.3%. This study indicated that the combination of quantitative and chromatographic fingerprint analysis can be readily utilized as a quality control method for S. flavescens and its related traditional Chinese medicinal preparations.

Comparison of high-performance liquid chromatography and supercritical fluid chromatography using evaporative light scattering detection for the determination of plasticizers in medical devices.

PubMed

Lecoeur, Marie; Decaudin, Bertrand; Guillotin, Yoann; Sautou, Valérie; Vaccher, Claude

2015-10-23

Recently, interest in supercritical fluid chromatography (SFC) has increased due to its high throughput and the development of new system improving chromatographic performances. However, most papers dealt with fundamental studies and chiral applications and only few works described validation process of SFC method. Likewise, evaporative light scattering detection (ELSD) has been widely employed in liquid chromatography but only a few recent works presented its quantitative performances hyphenated with SFC apparatus. The present paper discusses about the quantitative performances of SFC-ELSD compared to HPLC-ELSD, for the determination of plasticizers (ATBC, DEHA, DEHT and TOTM) in PVC tubing used as medical devices. After the development of HPLC-ELSD, both methods were evaluated based on the total error approach using accuracy profile. The results show that HPLC-ELSD was more precise than SFC-ELSD but lower limits of quantitation were obtained by SFC. Hence, HPLC was validated in the ± 10% acceptance limits whereas SFC lacks of accuracy to quantify plasticizers. Finally, both methods were used to determine the composition of plasticized-PVC medical devices. Results demonstrated that SFC and HPLC both hyphenated with ELSD provided similar results. Copyright © 2015 Elsevier B.V. All rights reserved.

Improved Quantitation of Gluten in Wheat Starch for Celiac Disease Patients by Gel-Permeation High-Performance Liquid Chromatography with Fluorescence Detection (GP-HPLC-FLD).

PubMed

Scherf, Katharina Anne; Wieser, Herbert; Koehler, Peter

2016-10-12

Purified wheat starch (WSt) is commonly used in gluten-free products for celiac disease (CD) patients. It is mostly well-tolerated, but doubts about its safety for CD patients persist. One reason may be that most ELISA kits primarily recognize the alcohol-soluble gliadin fraction of gluten, but insufficiently target the alcohol-insoluble glutenin fraction. To address this problem, a new sensitive method based on the sequential extraction of gliadins, glutenins, and gluten from WSt followed by gel-permeation high-performance liquid chromatography with fluorescence detection (GP-HPLC-FLD) was developed. It revealed that considerable amounts of glutenins were present in most WSt. The gluten contents quantitated by GP-HPLC-FLD as sum of gliadins and glutenins were higher than those by R5 ELISA (gluten as gliadin content multiplied by a factor of 2) in 19 out of 26 WSt. Despite its limited selectivity, GP-HPLC-FLD may be applied as confirmatory method to ELISA to quantitate gluten in WSt.

Matrix effects break the LC behavior rule for analytes in LC-MS/MS analysis of biological samples

USDA-ARS?s Scientific Manuscript database

High-performance liquid chromatography (HPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) are generally accepted as the preferred techniques for detecting and quantitating analytes of interest in biological matrices on the basis of the rule that one chemical compound yields one LC-...

HPLC-high-resolution mass spectrometry with polarity switching for increasing throughput of human in vitro cocktail drug-drug interaction assay.

PubMed

Ramanathan, Ragu; Ghosal, Anima; Ramanathan, Lakshmi; Comstock, Kate; Shen, Helen; Ramanathan, Dil

2018-05-01

Evaluation of HPLC-high-resolution mass spectrometry (HPLC-HRMS) full scan with polarity switching for increasing throughput of human in vitro cocktail drug-drug interaction assay. Microsomal incubates were analyzed using a high resolution and high mass accuracy Q-Exactive mass spectrometer to collect integrated qualitative and quantitative (qual/quant) data. Within assay, positive-to-negative polarity switching HPLC-HRMS method allowed quantification of eight and two probe compounds in the positive and negative ionization modes, respectively, while monitoring for LOR and its metabolites. LOR-inhibited CYP2C19 and showed higher activity for CYP2D6, CYP2E1 and CYP3A4. Overall, LC-HRMS-based nontargeted full scan quantitation allowed to improve the throughput of the in vitro cocktail drug-drug interaction assay.

Precision of dehydroascorbic acid quantitation with the use of the subtraction method--validation of HPLC-DAD method for determination of total vitamin C in food.

PubMed

Mazurek, Artur; Jamroz, Jerzy

2015-04-15

In food analysis, a method for determination of vitamin C should enable measuring of total content of ascorbic acid (AA) and dehydroascorbic acid (DHAA) because both chemical forms exhibit biological activity. The aim of the work was to confirm applicability of HPLC-DAD method for analysis of total content of vitamin C (TC) and ascorbic acid in various types of food by determination of validation parameters such as: selectivity, precision, accuracy, linearity and limits of detection and quantitation. The results showed that the method applied for determination of TC and AA was selective, linear and precise. Precision of DHAA determination by the subtraction method was also evaluated. It was revealed that the results of DHAA determination obtained by the subtraction method were not precise which resulted directly from the assumption of this method and the principles of uncertainty propagation. The proposed chromatographic method should be recommended for routine determinations of total vitamin C in various food. Copyright © 2014 Elsevier Ltd. All rights reserved.

Quantitative high-performance liquid chromatography of nucleosides in biological materials.

PubMed

Gehrke, C W; Kuo, K C; Davis, G E; Suits, R D; Waalkes, T P; Borek, E

1978-03-21

A rigorous, comprehensive, and reliable reversed-phase high-performance liquid chromatographic (HPLC) method has been developed for the analysis of ribonucleosides in urine (psi, m1A, m1I, m2G, A, m2(2)G). An initial isolation of ribonucleosides with an affinity gel containing an immobilized phenylboronic acid was used to improve selectivity and sensitivity. Response for all nucleosides was linear from 0.1 to 50 nmoles injected and good quantitation was obtained for 25 microliter or less of sample placed on the HPLC column. Excellent precision of analysis for urinary nucleosides was achieved on matrix dependent and independent samples, and the high resolution of the reversed-phase column allowed the complete separation of 9 nucleosides from other unidentified UV absorbing components at the 1-ng level. Supporting experimental data are presented on precision, recovery, chromatographic methods, minimum detection limit, retention time, relative molar response, sample clean-up, stability of nucleosides, boronate gel capacity, and application to analysis of urine from patients with leukemia and breast cancer. This method is now being used routinely for the determination of the concentration and ratios of nucleosides in urine from patients with different types of cancer and in chemotherapy response studies.

Rapid analysis of 2,4-D in soil samples by modified Soxhlet apparatus using HPLC with UV detection.

PubMed

Kashyap, Sanjay M; Pandya, Girish H; Kondawar, Vivek K; Gabhane, Sanjay S

2005-02-01

The 2,4-dichlorophenoxy acetic acid (2,4-D) is used as a systemic herbicide to control broadleaf weeds in wheat, corn, range land/pasture land, sorghum, and barley. In this study, a fast and efficient method is developed by selection of modified extraction apparatus and high-performance liquid chromatography (HPLC)-UV conditions for the determination of 2,4-D in soil samples. The method is applied to the study of soil samples collected from the agricultural field. The herbicide is extracted from soil samples by acetonitrile in a modified Soxhlet apparatus. The advantages of the apparatus are that it uses small volume of organic solvent, reduced time of extraction, and better recovery of the analyte. The extract is filtered using a very fine microfiber paper. The total extract is concentrated in a rotatory evaporator, dried under ultrahigh pure N2, and finally reconstituted in 1 mL of acetonitrile. HPLC-UV at 228 nm is used for analysis. The herbicide is identified and quantitated using the HPLC system. The method is validated by the analysis of spiked soil samples. Recoveries obtained varied from 85% to 100% for spiked soil samples. The limit of quantitation (LOQ) and the limit of detection (LOD) are 0.010 and 0.005 parts per million (ppm), respectively, for spiked soil samples. The LOQ and LOD are 0.006 and 0.003 ppm for unspiked soil samples. The measured concentrations of 2,4-D in spiked soil samples are between 0.010 and 0.020 ppm with an average of 0.016 +/- 0.003 ppm. For unspiked soil samples it is between 0.006 ppm and 0.012 ppm with an average of 0.009 +/- 0.002 ppm. The measured concentrations of 2,4-D in soil samples are generally low and do not exceed the regulatory agencies guidelines.

A novel approach of periodate oxidation coupled with HPLC-FLD for the quantitative determination of 3-chloro-1,2-propanediol in water and vegetable oil.

PubMed

Hu, Zhixiong; Cheng, Peng; Guo, Mingli; Zhang, Weinong; Qi, Yutang

2013-07-10

A novel approach of periodate oxidation coupled with high-performance liquid chromatography (HPLC)-fluorescence detection (FLD) for the quantitative determination of 3-chloro-1,2-propanediol (3-MCPD) has been established. The essence of this approach lies in the production of chloroacetaldehyde by the oxidization cleavage of 3-MCPD with sodium periodate and the HPLC analysis of chloroacetaldehyde monitored by an FLD detector after fluorescence derivatization with adenine. The experimental parameters relating to the efficiency of the derivative reaction such as concentration of adenine, chloroacetaldehyde reaction temperature, and time were studied. Under the optimized conditions, the proposed method can provide high sensitivity, good linearity (r(2) = 0.999), and repeatability (percent relative standard deviations between 2.57% and 3.44%), the limits of detection and quantification were 0.36 and 1.20 ng/mL, respectively, and the recoveries obtained for water samples were in the range 93.39-97.39%. This method has been successfully applied to the analysis of real water samples. Also this method has been successfully used for the analysis of vegetable oil samples after pretreatment with liquid-liquid extraction; the recoveries obtained by a spiking experiment with soybean oil ranged from 96.27% to 102.42%. In comparison with gas chromatography or gas chromatography-mass spectrometry, the proposed method can provide the advantages of simple instrumental requirement, easy operation, low cost, and high efficiency, thus making this approach another good choice for the sensitive determination of 3-MCPD.

A sensitive and rapid assay for 4-aminophenol in paracetamol drug and tablet formulation, by flow injection analysis with spectrophotometric detection.

PubMed

Bloomfield, M S

2002-12-06

4-Aminophenol (4AP) is the primary degradation product of paracetamol which is limited at a low level (50 ppm or 0.005% w/w) in the drug substance by the European, United States, British and German Pharmacopoeias, employing a manual colourimetric limit test. The 4AP limit is widened to 1000 ppm or 0.1% w/w for the tablet product monographs, which quote the use of a less sensitive automated HPLC method. The lower drug substance specification limit is applied to our products, (50 ppm, equivalent to 25 mug 4AP in a tablet containing 500-mg paracetamol) and the pharmacopoeial HPLC assay was not suitable at this low level due to matrix interference. For routine analysis a rapid, automated assay was required. This paper presents a highly sensitive, precise and automated method employing the technique of Flow Injection (FI) analysis to quantitatively assay low levels of this degradant. A solution of the drug substance, or an extract of the tablets, containing 4AP and paracetamol is injected into a solvent carrier stream and merged on-line with alkaline sodium nitroprusside reagent, to form a specific blue derivative which is detected spectrophotometrically at 710 nm. Standard HPLC equipment is used throughout. The procedure is fully quantitative and has been optimised for sensitivity and robustness using a multivariate experimental design (multi-level 'Central Composite' response surface) model. The method has been fully validated and is linear down to 0.01 mug ml(-1). The approach should be applicable to a range of paracetamol products.

Quantitative determination and classification of energy drinks using near-infrared spectroscopy.

PubMed

Rácz, Anita; Héberger, Károly; Fodor, Marietta

2016-09-01

Almost a hundred commercially available energy drink samples from Hungary, Slovakia, and Greece were collected for the quantitative determination of their caffeine and sugar content with FT-NIR spectroscopy and high-performance liquid chromatography (HPLC). Calibration models were built with partial least-squares regression (PLSR). An HPLC-UV method was used to measure the reference values for caffeine content, while sugar contents were measured with the Schoorl method. Both the nominal sugar content (as indicated on the cans) and the measured sugar concentration were used as references. Although the Schoorl method has larger error and bias, appropriate models could be developed using both references. The validation of the models was based on sevenfold cross-validation and external validation. FT-NIR analysis is a good candidate to replace the HPLC-UV method, because it is much cheaper than any chromatographic method, while it is also more time-efficient. The combination of FT-NIR with multidimensional chemometric techniques like PLSR can be a good option for the detection of low caffeine concentrations in energy drinks. Moreover, three types of energy drinks that contain (i) taurine, (ii) arginine, and (iii) none of these two components were classified correctly using principal component analysis and linear discriminant analysis. Such classifications are important for the detection of adulterated samples and for quality control, as well. In this case, more than a hundred samples were used for the evaluation. The classification was validated with cross-validation and several randomization tests (X-scrambling). Graphical Abstract The way of energy drinks from cans to appropriate chemometric models.

Near-Infrared Spectroscopy Assay of Key Quality-Indicative Ingredients of Tongkang Tablets.

PubMed

Pan, Wenjie; Ma, Jinfang; Xiao, Xue; Huang, Zhengwei; Zhou, Huanbin; Ge, Fahuan; Pan, Xin

2017-04-01

The objective of this paper is to develop an easy and fast near-infrared spectroscopy (NIRS) assay for the four key quality-indicative active ingredients of Tongkang tablets by comparing the true content of the active ingredients measured by high performance liquid chromatography (HPLC) and the NIRS data. The HPLC values for the active ingredients content of Cimicifuga glycoside, calycosin glucoside, 5-O-methylvisamminol and hesperidin in Tongkang tablets were set as reference values. The NIRS raw spectra of Tongkang tablets were processed using first-order convolution method. The iterative optimization method was chosen to optimize the band for Cimicifuga glycoside and 5-O-methylvisamminol, and correlation coefficient method was used to determine the optimal band of calycosin glucoside and hesperidin. A near-infrared quantitative calibration model was established for each quality-indicative ingredient by partial least-squares method on the basis of the contents detected by HPLC and the obtained NIRS spectra. The correlation coefficient R 2 values of the four models of Cimicifuga glycoside, calycosin glucoside, 5-O-methylvisamminol and hesperidin were 0.9025, 0.8582, 0.9250, and 0.9325, respectively. It was demonstrated that the accuracy of the validation values was approximately 90% by comparison of the predicted results from NIRS models and the HPLC true values, which suggested that NIRS assay was successfully established and validated. It was expected that the quantitative analysis models of the four indicative ingredients could be used to rapidly perform quality control in industrial production of Tongkang tablets.

Simultaneous separation and quantitation of amino acids and polyamines of forest tree tissues and cell cultures within a single high-performance liquid chromatography run using dansyl derivatization

Treesearch

Rakesh Minocha; Stephanie Long

2004-01-01

The objective of the present study was to develop a rapid HPLC method for simultaneous separation and quantitation of dansylated amino acids and common polyamines in the same matrix for analyzing forest tree tissues and cell cultures. The major modifications incorporated into this method as compared to previously published HPLC methods for separation of only dansyl...

Quantitative fundus autofluorescence in mice: correlation with HPLC quantitation of RPE lipofuscin and measurement of retina outer nuclear layer thickness.

PubMed

Sparrow, Janet R; Blonska, Anna; Flynn, Erin; Duncker, Tobias; Greenberg, Jonathan P; Secondi, Roberta; Ueda, Keiko; Delori, François C

2013-04-17

Our study was conducted to establish procedures and protocols for quantitative autofluorescence (qAF) measurements in mice, and to report changes in qAF, A2E bisretinoid concentration, and outer nuclear layer (ONL) thickness in mice of different genotypes and age. Fundus autofluorescence (AF) images (55° lens, 488 nm excitation) were acquired in albino Abca4(-/-), Abca4(+/-), and Abca4(+/+) mice (ages 2-12 months) with a confocal scanning laser ophthalmoscope (cSLO). Gray levels (GLs) in each image were calibrated to an internal fluorescence reference. The bisretinoid A2E was measured by quantitative high performance liquid chromatography (HPLC). Histometric analysis of ONL thicknesses was performed. The Bland-Altman coefficient of repeatability (95% confidence interval) was ±18% for between-session qAF measurements. Mean qAF values increased with age (2-12 months) in all groups of mice. qAF was approximately 2-fold higher in Abca4(-/-) mice than in Abca4(+/+) mice and approximately 20% higher in heterozygous mice. HPLC measurements of the lipofuscin fluorophore A2E also revealed age-associated increases, and the fold difference between Abca4(-/-) and wild-type mice was more pronounced (approximately 3-4-fold) than measurable by qAF. Moreover, A2E levels declined after 8 months of age, a change not observed with qAF. The decline in A2E levels in the Abca4(-/-) mice corresponded to reduced photoreceptor cell viability as reflected in ONL thinning beginning at 8 months of age. The qAF method enables measurement of in vivo lipofuscin and the detection of genotype and age-associated differences. The use of this approach has the potential to aid in understanding retinal disease processes and will facilitate preclinical studies.

Simultaneous determination of nine saponins from Panax notoginseng using HPLC and pressurized liquid extraction.

PubMed

Wan, J B; Lai, C M; Li, S P; Lee, M Y; Kong, L Y; Wang, Y T

2006-04-11

A HPLC and pressurized liquid extraction (PLE) method was developed for simultaneous determination of nine saponins, including notoginsenoside R1, ginsenoside Rg1, Re, Rf, Rb1, Rc, Rb2, Rb3 and Rd in Panax notoginseng. The analysis was performed on C18 column with water-acetonitrile gradient elution and the investigated saponins were authenticated by comparing retention time and mass spectra with their reference compounds. Several methods including PLE, ultrasonication, soxhlet extraction and immersion were used for sample preparation and their extraction efficiency was compared. The results showed that PLE has the highest extraction efficiency and repeatability, which would be valuable on standardization of sample preparation for quality control of Chinese medicines. The developed HPLC and PLE is an effective approach for simultaneously quantitative determination of sapoinins in P. notoginseng, which could be used for quality control of P. notoginseng and its preparations.

Identification of ionic chloroacetanilide-herbicide metabolites in surface water and groundwater by HPLC/MS using negative ion spray

USGS Publications Warehouse

Ferrer, I.; Thurman, E.M.; Barcelo, D.

1997-01-01

Solid-phase extraction (SPE) was combined with high-performance liquid chromatography/high-flow pneumatically assisted electrospray mass spectrometry (HPLC/ESP/MS) for the trace analysis of oxanilic and sulfonic acids of acetochlor, alachlor, and metolachlor. The isolation procedure separated the chloroacetanilide metabolites from the parent herbicides during the elution from C18 cartridges using ethyl acetate for parent compounds, followed by methanol for the anionic metabolites. The metabolites were separated chromatographically using reversed-phase HPLC and analyzed by negative-ion MS using electrospray ionization in selected ion mode. Quantitation limits were 0.01 ??g/L for both the oxanilic and sulfonic acids based on a 100-mL water sample. This combination of methods represents an important advance in environmental analysis of chloroacetanilide-herbicide metabolites in surface water and groundwater for two reasons. First, anionic chloroacetanilide metabolites are a major class of degradation products that are readily leached to groundwater in agricultural areas. Second, anionic metabolites, which are not able to be analyzed by conventional methods such as liquid extraction and gas chromatography/mass spectrometry, are effectively analyzed by SPE and high-flow pneumatically assisted electrospray mass spectrometry. This paper reports the first HPLC/MS identification of these metabolites in surface water and groundwater.

A reliable methodology for quantitative extraction of fruit and vegetable physiological amino acids and their subsequent analysis with commonly available HPLC systems

USDA-ARS?s Scientific Manuscript database

High performance liquid chromatography of dabsyl derivatives of amino acids was employed for quantification of physiological amino acids in selected fruits and vegetables. This method was found to be particularly useful because the dabsyl derivatives of glutamine and citrulline were sufficiently se...

Advances in HPLC-ICP-MS interface techniques for metal speciation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hill, S.J.

The relentless demand for lower detection limits is increasingly coupled to the requirement for elemental speciation. This is particularly true in environmental and clinical fields where total levels are often insufficient for mobility and toxicity studies. This demand for both qualitative and quantitative data on the individual species present in complex samples has led to the development of various interfaces to couple some form of chromatography, usually gas chromatography (GC) or high performance liquid chromatography (HPLC) to an element specific detector. Today inductively coupled plasma-mass spectrometry is often employed since it offers excellent detection limits, element specific information (including isotopicmore » data) and the potential for multi-element studies. Ms presentation will concentrate on HPLC couplings although the advantages and disadvantages of both GC and HPLC couplings to ICP-MS will be discussed. Particular attention will be given to the optimization of both the chromatography and detection systems. Details will be presented of several successful HPLC interface designs and ways of facilitating high levels of a range of organic solvents (e.g. methanol and THF) in the HPLC mobile phase will be highlighted. The advantages of using a sheath gas and practical ways of achieving this will also be discussed. Finally the use of isotope dilution analysis in conjunction with HPLC-ICP-MS will be outlined. In all cases the impact of using the most appropriate approach will be demonstrated using both environmental and clinical samples.« less

Separation and quantitation of debrisoquine and 4-hydroxydebrisoquine in human urine by capillary electrophoresis and high-performance liquid chromatography.

PubMed

Cifuentes, A; Valencia, J; Sanz, E; Sánchez, M J; Rodríguez-Delgado, M A

1997-08-22

A comparative study on the use of reversed-phase high-performance liquid chromatography (RP-HPLC) and capillary electrophoresis (CE) for the determination of debrisoquine (D) and its metabolite, 4-hydroxydebrisoquine (4-HD), in human urine is presented. Four different urine pre-treatments are compared for purification of samples prior to their injection in HPLC and CE. The use of a solid-phase extraction with a C18 cartridge provides the best results for the urine sample treatment, with good recoveries, i.e., 94.5% for D and 93.4% for 4-HD, and high reproducibility, i.e., R.S.D. N = 10 values of 1.7% and 1.2%, respectively. Under our separation conditions it is shown that CE is twice as fast and provides slightly better analysis time reproducibility than HPLC for this type of sample. Both the sensitivity and peak area reproducibility are better when HPLC is used. The two techniques show good agreement when employed for determination of phenotypes for hydroxylation, which seems to corroborate the usefulness of CE for this type of study.

On-line HPLC-DPPH screening method for evaluation of radical scavenging phenols extracted from apples (Malus domestica L.).

PubMed

Bandoniene, Donata; Murkovic, Michael

2002-04-24

An on-line HPLC-DPPH screening method for phenolic antioxidants in apple methanol/water (80:20, v/v) extracts was applied. The determination of antioxidants was based on a decrease in absorbance at 515 nm after postcolumn reaction of HPLC-separated antioxidants with the 2,2'-diphenyl-1-picrylhydrazyl radicals (DPPH*). Each of the antioxidants separated by the HPLC column was observed as a negative peak corresponding to its antioxidative activity. The on-line method was applied for quantitative analysis of the antioxidants. A linear dependence of negative peak area on concentration of the reference antioxidants was observed. For validation of the on-line method the limit of detection, LOD (microg/mL), and the limit of quantification, LOQ (microg/mL), of the phenolic compounds were determined. Comparison of the UV and DPPH radical quenching chromatograms with authentic compounds identified catechin, chlorogenic acid, caffeic acid, epicatechin, and phloridzin in the apple cultivars (Lobo, Golden Delicious, and Boskoop), and the distribution of total antioxidant activity was calculated.

Quantitative and pattern recognition analyses of magnoflorine, spinosin, 6'''-feruloyl spinosin and jujuboside A by HPLC in Zizyphi Semen.

PubMed

Kim, Won Il; Zhao, Bing Tian; Zhang, Hai Yan; Lee, Je Hyun; Son, Jong Keun; Woo, Mi Hee

2014-01-01

Two rapid and simple HPLC methods with UV detector to determine three main compounds (magnoflorine, spinosin and 6'''-feruloyl spinosin) and evaporative light scattering detector (ELSD) to determine jujuboside A were developed for the chemical analyses of Zizyphi Semen. Magnoflorine, spinosin, and 6'''-feruloyl spinosin were separated with an YMC J'sphere ODS-H80 column (250 mm × 4.6 mm, 4 μm) by the gradient elution followed by the isocratic elution using methanol with 0.1 % formic acid and water with 0.1 % formic acid as the mobile phase. The flow rate was 1.0 mL/min. Jujuboside A was separated by HPLC-ELSD with YoungJinBioChrom Aegispak C18-L column (250 mm × 4.6 mm, 5 μm) column in a gradient elution using methanol with 0.1 % formic acid (A) and water with 0.1 % formic acid as the mobile phase. These two methods were fully validated with respect to linearity, precision, accuracy, stability, and robustness. These HPLC methods were applied successfully to quantify four compounds in a Zizyphi Semen extract. The HPLC analytical methods were validated for pattern recognition analysis by repeated analysis of 91 seed samples corresponding to 48 Zizyphus jujuba var. spinosa (J01-J48) and 43 Zizyphus mauritiana (M01-M43). The results indicate that these methods are suitable for a quality evaluation of Zizyphi Semen.

Quantitation of zolpidem in biological fluids by electro-driven microextraction combined with HPLC-UV analysis.

PubMed

Yaripour, Saeid; Mohammadi, Ali; Esfanjani, Isa; Walker, Roderick B; Nojavan, Saeed

2018-01-01

In this study, for the first time, an electro-driven microextraction method named electromembrane extraction combined with a simple high performance liquid chromatography and ultraviolet detection was developed and validated for the quantitation of zolpidem in biological samples. Parameters influencing electromembrane extraction were evaluated and optimized. The membrane consisted of 2-ethylhexanol immobilized in the pores of a hollow fiber. As a driving force, a 150 V electric field was applied to facilitate the analyte migration from the sample matrix to an acceptor solution through a supported liquid membrane. The pHs of donor and acceptor solutions were optimized to 6.0 and 2.0, respectively. The enrichment factor was obtained >75 within 15 minutes. The effect of carbon nanotubes (as solid nano-sorbents) on the membrane performance and EME efficiency was evaluated. The method was linear over the range of 10-1000 ng/mL for zolpidem (R 2 >0.9991) with repeatability ( %RSD) between 0.3 % and 7.3 % ( n = 3). The limits of detection and quantitation were 3 and 10 ng/mL, respectively. The sensitivity of HPLC-UV for the determination of zolpidem was enhanced by electromembrane extraction. Finally, the method was employed for the quantitation of zolpidem in biological samples with relative recoveries in the range of 60-79 %.

Quantitation of zolpidem in biological fluids by electro-driven microextraction combined with HPLC-UV analysis

PubMed Central

Yaripour, Saeid; Mohammadi, Ali; Esfanjani, Isa; Walker, Roderick B.; Nojavan, Saeed

2018-01-01

In this study, for the first time, an electro-driven microextraction method named electromembrane extraction combined with a simple high performance liquid chromatography and ultraviolet detection was developed and validated for the quantitation of zolpidem in biological samples. Parameters influencing electromembrane extraction were evaluated and optimized. The membrane consisted of 2-ethylhexanol immobilized in the pores of a hollow fiber. As a driving force, a 150 V electric field was applied to facilitate the analyte migration from the sample matrix to an acceptor solution through a supported liquid membrane. The pHs of donor and acceptor solutions were optimized to 6.0 and 2.0, respectively. The enrichment factor was obtained >75 within 15 minutes. The effect of carbon nanotubes (as solid nano-sorbents) on the membrane performance and EME efficiency was evaluated. The method was linear over the range of 10-1000 ng/mL for zolpidem (R2 >0.9991) with repeatability ( %RSD) between 0.3 % and 7.3 % (n = 3). The limits of detection and quantitation were 3 and 10 ng/mL, respectively. The sensitivity of HPLC-UV for the determination of zolpidem was enhanced by electromembrane extraction. Finally, the method was employed for the quantitation of zolpidem in biological samples with relative recoveries in the range of 60-79 %. PMID:29805344

Qualitative and quantitative analysis of flavonoids in Sophora tonkinensis by LC/MS and HPLC.

PubMed

He, Chang-Ming; Cheng, Zhi-Hong; Chen, Dao-Feng

2013-11-01

To develop analytical methods for the identification and determination of the flavonoids in Sophora tonkinensis for comprehensive quality evaluation. An HPLC-DAD-ESI-MS method was used for the separation and characterization of the flavonoids in S. tonkinensis, and a liquid chromatographic method was employed to simultaneously determine five major active flavonoids in this crude drug. Seventeen flavonoids were identified, among which, seven were unambiguously identified as trifolirhizin, quercetin, formononetin, macckiain, kurarinone, sophoranone, and sophoranochromene by comparing their retention times, and UV and MS spectra with those of the authentic compounds, and the other ten flavonoids were tentatively identified by comparing their UV and MS/MS spectra with those of literature data. Furthermore, five major active flavonoids, including trifolirhizin, quercetin, maackiain, sophoranone, and sophoranochromene were determined in S. tonkinensis. All calibration curves expressed good linearity (r > 0.999 8) within the test ranges, and the recovery from this method was 96.40%-104.43%. The developed HPLC method was successfully applied to quantitatively determine the five flavonoids in seventeen samples of S. tonkinensis. The developed method rapidly characterized the bioactive flavonoids of S. tonkinensis, and could be readily utilized to enhance the quality assurance approaches for this traditional Chinese medicine. Copyright © 2013 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

Identification and Quantification of Alkaloid in KHR98 and Fragmentation Pathways in HPLC-Q-TOF-MS.

PubMed

Long, Jiakun; Wang, Yang; Xu, Chen; Liu, Tingting; Duan, Gengli; Yu, Yingjia

2018-05-01

Uncaria rhynchophylla is woody climber plant distributed mainly in China and Japan, the stems and hooks of which can be collected as "Gou-Teng" for the treatment of hyperpyrexia, epilepsy and preeclampsia. Fudan University first manufactured KHR98, the extract of Uncaria rhynchophylla. In order to study the active components and structural information of KHR98, we established a HPLC coupled with quadrupole time-of-flight (Q-TOF)-MS method for rapid analysis of alkaloids. In qualitative analysis, a total of eight compounds, including four known alkaloids and four unknown components, were detected and identified. The fragmentation behaviors, such as the fragment ion information and the fragmentation pathways of the eight components were summarized simultaneously, and the concentration of the above components was determined by HPLC-MS method. The quantitative method was proved to be reproducible, precise and accurate. This study shed light on the standardization and quality control of the KHR98 and provided a foundation for the further research on pharmacology, follow-up clinical research and New Drug Applications.

Study on the Multi-marker Components Quantitative HPLC Fingerprint of the Compound Chinese Medicine Wuwei Changyanning Granule

PubMed Central

Yang, Xian; Yang, Shui-Ping; Zhang, Xue; Yu, Xiao-Dong; He, Qi-Yi; Wang, Bo-Chu

2014-01-01

The aim of this paper is to develop a rapid and highly sensitive quantitative HPLC fingerprint method with multiple indicators by using the Compound Chinese Medicine Wuwei Changyanning granule and 5 herbs in the prescription. The quantitative fingerprint chromatogram with multiple indicators was investigated. і)6 compositions included rutin, gallic acid, chlorogenic acid, atractylenolide Ⅰ, pachymic acid and apigenin, which originated from 5 herbs respectively, were selected as quantitative compositions, and their contents were determined using HPLC from 11 batches granules and the corresponding 5 medicinal materials. ⅱ) The precision, stability and repeatability of fingerprinting were investigated. In addition, common peaks number, the percentage of non-common peaks and similarity were also studied. Among them, 21 common peaks in the granule could find the source of peaks from the 5 herbs, among of 10 peaks from Niuerfeng, 9 peaks from Laliao, 3 peaks from Baishu, 3 peaks from Fuling and 5 peaks from Guanghuoxiang. The results showed that the identification method of fingerprinting was reliable. PMID:25587307

Pungency Quantitation of Hot Pepper Sauces Using HPLC

NASA Astrophysics Data System (ADS)

Betts, Thomas A.

1999-02-01

A class of compounds known as capsaicinoids are responsible for the "heat" of hot peppers. To determine the pungency of a particular pepper or pepper product, one may quantify the capsaicinoids and relate those concentrations to the perceived heat. The format of the laboratory described here allows students to collectively develop an HPLC method for the quantitation of the two predominant capsaicinoids (capsaicin and dihydrocapsaicin) in hot-pepper products. Each small group of students investigated one of the following aspects of the method: detector wavelength, mobile-phase composition, extraction of capsaicinoids, calibration, and quantitation. The format of the lab forced students to communicate and cooperate to develop this method. The resulting HPLC method involves extraction with acetonitrile followed by solid-phase extraction clean-up, an isocratic 80:20 methanol-water mobile phase, a 4.6 mm by 25 cm C-18 column, and UV absorbance detection at 284 nm. The method developed by the students was then applied to the quantitation of capsaicinoids in a variety of hot pepper sauces. Editor's Note on Hazards in our April 2000 issue addresses the above.

Novel approaches to analysis of 3-chloropropane-1,2-diol esters in vegetable oils.

PubMed

Moravcova, Eliska; Vaclavik, Lukas; Lacina, Ondrej; Hrbek, Vojtech; Riddellova, Katerina; Hajslova, Jana

2012-03-01

A sensitive and accurate method utilizing ultrahigh performance liquid chromatography (U-HPLC) coupled to high resolution mass spectrometry based on orbitrap technology (orbitrapMS) for the analysis of nine 3-chloropropane-1,2-diol (3-MCPD) diesters in vegetable oils was developed. To remove the interfering triacylglycerols that induce strong matrix effects, a clean-up step on silica gel column was used. The quantitative analysis was performed with the use of deuterium-labeled internal standards. The lowest calibration levels estimated for the respective analytes ranged from 2 to 5 μg kg(-1). Good recovery values (89-120%) and repeatability (RSD 5-9%) was obtained at spiking levels of 2 and 10 mg kg(-1). As an alternative, a novel ambient desorption ionization technique, direct analysis in real time (DART), hyphenated with orbitrapMS, was employed for no separation, high-throughput, semi-quantitative screening of 3-MCPD diesters in samples obtained by chromatographic fractionation. Additionally, the levels of 3-MCPD diesters measured in reallife vegetable oil samples (palm oil, sunflower oil, rapeseed oil) using both methods are reported. Relatively good agreement of the data generated by U-HPLC-orbitrapMS and DART-orbitrapMS were observed. With regard to a low ionization yield achieved for 3-MCPD monoesters, the methods presented in this paper were not yet applicable for the analysis of these contaminants at the naturally occurring levels.

Determination of tocopheryl acetate and ascorbyl tetraisopalmitate in cosmetic formulations by HPLC.

PubMed

Almeida, M M; Alves, J M P; Patto, D C S; Lima, C R R C; Quenca-Guillen, J S; Santoro, M I R M; Kedor-Hackmann, E R M

2009-12-01

A rapid HPLC method was developed for the assay of tocopheryl acetate and ascorbyl tetraisopalmitate in cosmetic formulations. The validated method was applied for quantitative determination of these vitamins in simulated emulsion formulation. Samples were analysed directly on a RP-18 reverse phase column with UV detection at 222 nm. A mixture of methanol and isopropanol (25 : 75 v/v) was used as mobile phase. The retention time of tocopheryl acetate and ascorbyl tetraisopalmitate were 3.0 min and 5.9 min, respectively. Recovery was between 95% and 104%. In addition, the excipients did not interfere in the analysis. The method is simple, reproducible, selective and is suitable for routine analyses of commercial products.

2C-B: a new psychoactive phenylethylamine recently discovered in Ecstasy tablets sold on the Swiss black market.

PubMed

Giroud, C; Augsburger, M; Rivier, L; Mangin, P; Sadeghipour, F; Varesio, E; Veuthey, J L; Kamalaprija, P

1998-09-01

This study sought to identify, by means of several analytical methods (GC-MS, HPLC-DAD, CE-DAD, FTIR, and NMR), 4-bromo-2,5-dimethoxyphenethylamine (2C-B), which was found in two sets of tablets obtained from the Swiss black market. Unequivocal identification of 2C-B was only achieved by a combination of mass spectrometric and NMR analysis. Quantitation of 2C-B was performed by HPLC-DAD and CE-DAD. The amounts of 2C-B found in the tablets (3-8 mg) were in the range of the minimum quantity required to induce the effects characteristic of this drug.

[Study on quality standard of Mucuna pruriens var. utilis].

PubMed

Wu, Shi-Hong; Jiang, Wei-Zhe; Lv, Li; Wu, Ling-Ling; Lv, Cong; Shi, Xiao-Xia; Su, Gui-Liang

2009-03-01

To provide scientific basis for the utilization and development of Mucuna pruriens var. utilis by establishing its quality control standard. The bioactive constituents were analyzed by TLC and HPLC. Moisture, ash and the extracts of Mucuna pruriens var. utilis were all determined. The TLC spots of levodopa had similar color with the control group at the same position. The results of HPLC quantitative analysis showed that the linear range of levodopa was 26.45 to approximately 132.25 microg/mL, r = 0.9992, and the average recovery rate was 103.8%, RSD = 1.85%. This method is convenient, accurate, reliable with good reproducibility, so it can be used to establish quality standard for the medicinal material.

Quantitative analysis of PMR-15 polyimide resin by HPLC

NASA Technical Reports Server (NTRS)

Roberts, Gary D.; Lauver, Richard W.

1987-01-01

The concentration of individual components and of total solids of 50 wt pct PMR-15 resin solutions was determined using reverse-phase HPLC to within + or - 8 percent accuracy. Acid impurities, the major source of impurities in 3,3', 4,4'-benzophenonetetracarboxylic acid (BTDE), were eliminated by recrystallizing the BTDE prior to esterification. Triester formation was not a problem because of the high rate of esterification of the anhydride relative to that of the carboxylic acid. Aging of PMR-15 resin solutions resulted in gradual formation of the mononadimide and bisnadimide of 4,4'-methylenedianiline, with the BTDE concentration remaining constant. Similar chemical reactions occurred at a reduced rate in dried films of PMR-15 resin.

Quantitative analysis of the major constituents of St John's wort with HPLC-ESI-MS.

PubMed

Chandrasekera, Dhammitha H; Welham, Kevin J; Ashton, David; Middleton, Richard; Heinrich, Michael

2005-12-01

A method was developed to profile the major constituents of St John's wort extracts using high-performance liquid chromatography-electrospray mass spectrometry (HPLC-ESI-MS). The objective was to simultaneously separate, identify and quantify hyperforin, hypericin, pseudohypericin, rutin, hyperoside, isoquercetrin, quercitrin and chlorogenic acid using HPLC-MS. Quantification was performed using an external standardisation method with reference standards. The method consisted of two protocols: one for the analysis of flavonoids and glycosides and the other for the analysis of the more lipophilic hypericins and hyperforin. Both protocols used a reverse phase Luna phenyl hexyl column. The separation of the flavonoids and glycosides was achieved within 35 min and that of the hypericins and hyperforin within 9 min. The linear response range in ESI-MS was established for each compound and all had linear regression coefficient values greater than 0.97. Both protocols proved to be very specific for the constituents analysed. MS analysis showed no other signals within the analyte peaks. The method was robust and applicable to alcoholic tinctures, tablet/capsule extracts in various solvents and herb extracts. The method was applied to evaluate the phytopharmaceutical quality of St John's wort preparations available in the UK in order to test the method and investigate if they contain at least the main constituents and at what concentrations.

Automated sample preparation using membrane microtiter extraction for bioanalytical mass spectrometry.

PubMed

Janiszewski, J; Schneider, P; Hoffmaster, K; Swyden, M; Wells, D; Fouda, H

1997-01-01

The development and application of membrane solid phase extraction (SPE) in 96-well microtiter plate format is described for the automated analysis of drugs in biological fluids. The small bed volume of the membrane allows elution of the analyte in a very small solvent volume, permitting direct HPLC injection and negating the need for the time consuming solvent evaporation step. A programmable liquid handling station (Quadra 96) was modified to automate all SPE steps. To avoid drying of the SPE bed and to enhance the analytical precision a novel protocol for performing the condition, load and wash steps in rapid succession was utilized. A block of 96 samples can now be extracted in 10 min., about 30 times faster than manual solvent extraction or single cartridge SPE methods. This processing speed complements the high-throughput speed of contemporary high performance liquid chromatography mass spectrometry (HPLC/MS) analysis. The quantitative analysis of a test analyte (Ziprasidone) in plasma demonstrates the utility and throughput of membrane SPE in combination with HPLC/MS. The results obtained with the current automated procedure compare favorably with those obtained using solvent and traditional solid phase extraction methods. The method has been used for the analysis of numerous drug prototypes in biological fluids to support drug discovery efforts.

Industrial application of green chromatography - II. Separation and analysis of preservatives in skincare products using subcritical water chromatography.

PubMed

Yang, Y; Kapalavavi, B; Gujjar, L; Hadrous, S; Marple, R; Gamsky, C

2012-10-01

Several high-temperature liquid chromatography (HTLC) and subcritical water chromatography (SBWC) methods have been successfully developed in this study for separation and analysis of preservatives contained in Olay skincare creams. Efficient separation and quantitative analysis of preservatives have been achieved on four commercially available ZirChrom and Waters XBridge columns at temperatures ranging from 100 to 200°C. The quantification results obtained by both HTLC and SBWC methods developed for preservatives analysis are accurate and reproducible. A large number of replicate HTLC and SBWC runs also indicate no significant system building-up or interference for skincare cream analysis. Compared with traditional HPLC separation carried out at ambient temperature, the HTLC methods can save up to 90% methanol required in the HPLC mobile phase. However, the SBWC methods developed in this project completely eliminated the use of toxic organic solvents required in the HPLC mobile phase, thus saving a significant amount of money and making the environment greener. Although both homemade and commercial systems can accomplish SBWC separations, the SBWC methods using the commercial system for preservative analysis are recommended for industrial applications because they can be directly applied in industrial plant settings. © 2012 The Authors ICS © 2012 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

HPLC-DAD and HPLC-ESI-MS/MS methods for metabolite profiling of propolis extracts.

PubMed

Pellati, Federica; Orlandini, Giulia; Pinetti, Diego; Benvenuti, Stefania

2011-07-15

In this study, the composition of polyphenols (phenolic acids and flavonoids) in propolis extracts was investigated by HPLC-DAD and HPLC-ESI-MS/MS by comparing the performance of ion trap and triple quadrupole mass analyzers. The analyses were carried out on an Ascentis C(18) column (250mm×4.6mm I.D., 5μm), with a mobile phase composed by 0.1% formic acid in water and acetonitrile. Overall, the UV spectra, the MS and MS/MS data allowed the identification of 40 compounds. In the case of flavonoids, the triple quadrupole mass analyzer provided more collision energy if compared with the ion trap, originating product ions at best sensitivity. The HPLC method was validated in agreement with ICH guidelines: the correlation coefficients were >0.998; the limit of detection was in the range 1.6-4.6μg/ml; the recovery range was 96-105%; the intra- and inter-day %RSD values for retention times and peak areas were found to be <0.3 and 1.9%, respectively. The developed technique was applied to the analysis of hydroalcoholic extracts of propolis available on the Italian market. Although the chromatographic profile of the analyzed samples was similar, the quantitative analysis indicated that there is a great variability in the amount of the active compounds: the content of total phenolic acids ranged from 0.17 to 16.67mg/ml and the level of total flavonoids from 2.48 to 41.10mg/ml. The proposed method can be considered suitable for the phytochemical analysis of propolis extracts used in phytotherapy. Copyright © 2011 Elsevier B.V. All rights reserved.

Analysis of amide compounds in different parts of Piper ovatum Vahl by high-performance liquid chromatographic

PubMed Central

Silva, Daniel R.; Brenzan, Mislaine A.; Kambara, Lauro M.; Cortez, Lucia E. R.; Cortez, Diógenes A. G.

2013-01-01

Background: Piper ovatum (Piperaceae) has been used in traditional medicine for the treatment of inflammations and as an analgesic. Previous studies have showed important biological activities of the extracts and amides from P. ovatum leaves. Objective: In this study, a high-performance liquid chromatographic (HPLC) method was developed and validated for quantitative determination of the amides in different parts of Piper ovatum. Materials and Methods: The analysis was carried out on a Metasil ODS column (150 × 4.6 mm, 5μm) at room temperature. HPLC conditions were as follows: acetonitrile (A), and water (B), 1.0% acetic acid. The gradient elution used was 0–30 min, 0-60% A; 30–40 min, 60% A. Flow rate used was 1.0mL/min, and detection at 280nm. Results: The validation using piperlonguminine, as the standard, demonstrated that the method shows linearity (linear correlation coefficient = 0.998), precision (relative standard deviation <5%) and accuracy (mean recovery = 103.78%) in the concentration range 31.25 – 500μg/mL. The limit of detection and quantification were 1.21 and 4.03μg/mL, respectively. This method allowed the identification and quantification of piperlonguminine and piperovatine in the hydroethanolic extracts of P. ovatum obtained from the leaves, stems and roots. All the extracts showed the same chromatographic profile. The leaves and roots contained the highest concentrations of piperlonguminine and the stems and leaves showed the most concentrations of piperovatine. Conclusion: This HPLC method is suitable for routine quantitative analysis of amides in extracts of Piper ovatum and phytopharmaceuticals containing this herb. PMID:24174818

Quantitation of fumonisin B1 and B2 in feed using FMOC pre-column derivatization with HPLC and fluorescence detection.

PubMed

Smith, Lori L; Francis, Kyle A; Johnson, Joseph T; Gaskill, Cynthia L

2017-11-01

Pre-column derivatization with 9-fluorenylmethyl chloroformate (FMOC-Cl) was determined to be effective for quantitation of fumonisins B 1 and B 2 in feed. Liquid-solid extraction, clean-up using immunoaffinity solid phase extraction chromatography, and FMOC-derivatization preceded analysis by reverse phase HPLC with fluorescence. Instrument response was unchanged in the presence of matrix, indicating no need to use matrix-matched calibrants. Furthermore, high method recoveries indicated calibrants do not need to undergo clean-up to account for analyte loss. Established method features include linear instrument response from 0.04-2.5µg/mL and stable derivatized calibrants over 7days. Fortified cornmeal method recoveries from 0.1-30.0μg/g were determined for FB 1 (75.1%-109%) and FB 2 (96.0%-115.2%). Inter-assay precision ranged from 1.0%-16.7%. Method accuracy was further confirmed using certified reference material. Inter-laboratory comparison with naturally-contaminated field corn demonstrated equivalent results with conventional derivatization. These results indicate FMOC derivatization is a suitable alternative for fumonisins B 1 and B 2 quantitation in corn-based feeds. Copyright © 2017 Elsevier Ltd. All rights reserved.

A High-Performance Liquid Chromatography-Based Screening Method for the Analysis of Atrazine, Alachlor, and Ten of Their Transformation Products

USGS Publications Warehouse

Schroyer, B.R.; Capel, P.D.

1996-01-01

A high-performance liquid Chromatography (HPLC) method is presented for the for the fast, quantitative analysis of the target analytes in water and in low organic-carbon, sandy soils that are known to be contaminated with the parent herbicides. Speed and ease of sample preparation was prioritized above minimizing detection limits. Soil samples were extracted using 80:20 methanol:water (volume:volume). Water samples (50 ??L) were injected directly into the HPLC without prior preparation. Method quantification limits for soil samples (10 g dry weight) and water samples ranged from 20 to 110 ng/g and from 20 to 110 ??g/L for atrazine and its transformation products and from 80 to 320 ng/g and from 80 to 320 ??g/L for alachlor and its transformation products, respectively.

[Qualitative and quantitative analysis of amygdalin and its metabolite prunasin in plasma by ultra-high performance liquid chromatography-tandem quadrupole time of flight mass spectrometry and ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry].

PubMed

Gao, Meng; Wang, Yuesheng; Wei, Huizhen; Ouyang, Hui; He, Mingzhen; Zeng, Lianqing; Shen, Fengyun; Guo, Qiang; Rao, Yi

2014-06-01

A method was developed for the determination of amygdalin and its metabolite prunasin in rat plasma after intragastric administration of Maxing shigan decoction. The analytes were identified by ultra-high performance liquid chromatography-tandem quadrupole time of flight mass spectrometry and quantitatively determined by ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry. After purified by liquid-liquid extraction, the qualitative analysis of amygdalin and prunasin in the plasma sample was performed on a Shim-pack XR-ODS III HPLC column (75 mm x 2.0 mm, 1.6 microm), using acetonitrile-0.1% (v/v) formic acid aqueous solution. The detection was performed on a Triple TOF 5600 quadrupole time of flight mass spectrometer. The quantitative analysis of amygdalin and prunasin in the plasma sample was performed by separation on an Agilent C18 HPLC column (50 mm x 2.1 mm, 1.7 microm), using acetonitrile-0.1% (v/v) formic acid aqueous solution. The detection was performed on an AB Q-TRAP 4500 triple quadrupole mass spectrometer utilizing electrospray ionization (ESI) interface operated in negative ion mode and multiple-reaction monitoring (MRM) mode. The qualitative analysis results showed that amygdalin and its metabolite prunasin were detected in the plasma sample. The quantitative analysis results showed that the linear range of amygdalin was 1.05-4 200 ng/mL with the correlation coefficient of 0.999 0 and the linear range of prunasin was 1.25-2 490 ng/mL with the correlation coefficient of 0.997 0. The method had a good precision with the relative standard deviations (RSDs) lower than 9.20% and the overall recoveries varied from 82.33% to 95.25%. The limits of detection (LODs) of amygdalin and prunasin were 0.50 ng/mL. With good reproducibility, the method is simple, fast and effective for the qualitative and quantitative analysis of the amygdalin and prunasin in plasma sample of rats which were administered by Maxing shigan decoction.

Methods and applications of HPLC-AMS (WBio 5)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bucholz, B A; Clifford, A J; Duecker, S R

Pharmacokinetics of physiologic doses of nutrients, pesticides, and herbicides can easily be traced in humans using a {sup 14}C-labelled compound. Basic kinetics can be monitored in blood or urine by measuring the elevation in the {sup 14}C content above the control predose tissue and converting to equivalents of the parent compound. High Performance Liquid Chromatography (HPLC) is an excellent method for the chemical separation of complex mixtures whose profiles afford estimation of biochemical pathways of metabolism. Compounds elute from the HPLC systems with characteristic retention times and can be collected in fractions that can then be graphitized for AMS measurement.more » Unknowns are identified by coelution with known standards and chemical tests that reveal functional groupings. Metabolites are quantified with the {sup 14}C signal. Thoroughly accounting for the carbon inventory in the LC solvents, ion-pairing agents, samples, and carriers adds some complexity to the analysis. In most cases the total carbon inventory is dominated by carrier. Baseline background and stability need to be carefully monitored. Limits of quantitation near 10 amol of {sup 14}C per HPLC fraction are typically achieved. Baselines are maintained by limiting injected {sup 14}C activity <0.17 Bq (4.5 pCi) on the HPLC column.« less

Development of a micropulverized extraction method for rapid toxicological analysis of methamphetamine in hair.

PubMed

Miyaguchi, Hajime; Kakuta, Masaya; Iwata, Yuko T; Matsuda, Hideaki; Tazawa, Hidekatsu; Kimura, Hiroko; Inoue, Hiroyuki

2007-09-07

We developed a rapid sample preparation method for the toxicological analysis of methamphetamine and amphetamine (the major metabolite of methamphetamine) in human hair by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), to facilitate fast screening and quantitation. Two milligrams of hair were mechanically micropulverized for 5 min in a 2-ml plastic tube together with 100 microl of an aqueous solvent containing 10% acetonitrile, 100 mM trifluoroacetic acid and the corresponding deuterium analogues as internal standards. The pulverizing highly disintegrated the hair components, simultaneously allowing the extraction of any drugs present in the hair. After filtering the suspension with a membrane-filter unit, the clear filtrate was directly analyzed by HPLC-MS/MS. No evaporation processes were required for sample preparation. Method optimization and validation study were carried out using real-case specimens and fortified samples in which the drugs had been artificially absorbed, respectively. Concentration ranges for quantitation were 0.040-125 and 0.040-25 ng/mg for methamphetamine and amphetamine, respectively. Real-case specimens were analyzed by the method presented here and by conventional ones to verify the applicability of our method to real-world analysis. Our method took less than 30 min for a set of chromatograms to be obtained from a washed hair sample.

A rapid solid-phase extraction method for measurement of non-metabolised peripheral benzodiazepine receptor ligands, [(18)F]PBR102 and [(18)F]PBR111, in rat and primate plasma.

PubMed

Katsifis, Andrew; Loc'h, Christian; Henderson, David; Bourdier, Thomas; Pham, Tien; Greguric, Ivan; Lam, Peter; Callaghan, Paul; Mattner, Filomena; Eberl, Stefan; Fulham, Michael

2011-01-01

To develop a rapid and reliable method for estimating non-metabolised PBR ligands fluoroethoxy ([(18)F]PBR102)- and fluoropropoxy ([(18)F]PBR111)-substituted 2-(6-chloro-2-phenyl)imidazo[1,2-a]pyridine-3-yl)-N,N-diethylacetamides in plasma. Rats and baboons were imaged with PET up to 2 h postinjection of [(18)F]PBR102 and [(18)F]PBR111 under baseline conditions, after pre-blocking or displacement with PK11195. Arterial plasma samples were directly analysed by reverse-phase solid-phase extraction (RP-SPE) and RP-HPLC and by normal-phase TLC. SPE cartridges were successively washed with acetonitrile/water mixtures. SPE eluant radioactivity was measured in a γ-counter to determine the parent compound fraction and then analysed by HPLC and TLC for validation. In SPE, hydrophilic and lipophilic radiolabelled metabolites were eluted in water and 20% acetonitrile/water. All non-metabolised [(18)F]PBR102 and [(18)F]PBR111 were in SPE acetonitrile fraction as confirmed by HPLC and TLC analysis. Unchanged (%) [(18)F]PBR102 and [(18)F]PBR111 from SPE analysis in rat and baboon plasma agreed with those from HPLC and TLC analysis. In rats and baboons, the fraction of unchanged tracer followed a bi-exponential decrease, with half-lives of 7 to 10 min for the fast component and >80 min for the slow component for both tracers. Direct plasma SPE analysis of [(18)F]PBR102 and [(18)F]PBR111 can reliably estimate parent compound fraction. SPE was superior to HPLC for samples with low activity; it allows rapid and accurate metabolite analysis of a large number of plasma samples for improved estimation of metabolite-corrected input function during quantitative PET imaging studies. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.

Improved high-performance liquid chromatography (HPLC) method for qualitative and quantitative analysis of allantoin in Zea mays.

PubMed

Haghi, Ghasem; Arshi, Rohollah; Safaei, Alireza

2008-02-27

A high-performance liquid chromatography (HPLC) method for the qualitative and quantitative analysis of allantoin in silk and seed of Zea mays has been developed. Allantoin separation in crude extract was achieved using a C 18 column and phosphate buffer solution (pH 3.0) as a mobile phase at ambient temperature at a flow rate of 1.0 mL/min and detected at 210 nm. The results showed that the amount of allantoin in samples was between 14 and 271 mg/100 g of dry plant material. A comprehensive validation of the method including sensitivity, linearity, repeatability, and recovery was conducted. The calibration curve was linear over the range of 0.2-200 microg/mL with a correlation coefficient of r2>0.999. Limit of detection (LOD, S/N=3) and limit of quantification (LOQ) values of the allantoin were 0.05 and 0.2 microg/mL (1.0 and 4.0 ng) respectively. The relative standard deviation (RSD) value of the repeatability was reported within 1.2%. The average recovery of allantoin added to samples was 100.6% with RSD of 1.5%.

Determination of Flavonoids and Anthocyanins in Nitraria tangutorum by High Performance Liquid Chromatography Coupled with Tandem Mass Spectrometry.

PubMed

Zhe, Gao; Ying-Chun, Wang; Yan-Xu, Chang

2016-01-01

Using high-performance liquid chromatography coupled with diode array detection and electrospray ionization tandem mass spectrometry (HPLC-DAD-MSn) method, qualitative and quantitative analysis of flavonoids of stems, leaves, fruits and seeds, and anthocyanidin of fresh fruits in Nitraria tangutorum were performed. A total of 14 flavonoid components were identified from the seeds of N. tangutorum including three quercetin derivatives, three kaempferol derivatives, and eight isorhamnetin derivatives. A total of 12, 10, and 7 flavonoid components were identified from leaves, stems, and fruits of N. tangutorum, respectively; all were present in seeds also. The total content of flavonoids in leaves was the highest, up to 42.43 mg/g·dry weight. A total of 12 anthocyanidin components were identified from the fresh fruits of N. tangutorum, belonging to five anthocyanidin. The total content of anthocyanidin in fresh fruits was up to 45.83 mg/100 g· fresh weight, of which the acylated anthocyanidin accounted for 65.7%. The HPLC-DAD-MS(n) method can be operated easily, rapidly, and accurately, and is feasible for qualitative and quantitative analysis of flavone glycosides in N. tangutorum.

Sulfonium Ion Derivatization, Isobaric Stable Isotope Labeling and Data Dependent CID- and ETD-MS/MS for Enhanced Phosphopeptide Quantitation, Identification and Phosphorylation Site Characterization

PubMed Central

Lu, Yali; Zhou, Xiao; Stemmer, Paul M.; Reid, Gavin E.

2014-01-01

An amine specific peptide derivatization strategy involving the use of novel isobaric stable isotope encoded ‘fixed charge’ sulfonium ion reagents, coupled with an analysis strategy employing capillary HPLC, ESI-MS, and automated data dependent ion trap CID-MS/MS, -MS3, and/or ETD-MS/MS, has been developed for the improved quantitative analysis of protein phosphorylation, and for identification and characterization of their site(s) of modification. Derivatization of 50 synthetic phosphopeptides with S,S′-dimethylthiobutanoylhydroxysuccinimide ester iodide (DMBNHS), followed by analysis using capillary HPLC-ESI-MS, yielded an average 2.5-fold increase in ionization efficiencies and a significant increase in the presence and/or abundance of higher charge state precursor ions compared to the non-derivatized phosphopeptides. Notably, 44% of the phosphopeptides (22 of 50) in their underivatized states yielded precursor ions whose maximum charge states corresponded to +2, while only 8% (4 of 50) remained at this maximum charge state following DMBNHS derivatization. Quantitative analysis was achieved by measuring the abundances of the diagnostic product ions corresponding to the neutral losses of ‘light’ (S(CH3)2) and ‘heavy’ (S(CD3)2) dimethylsulfide exclusively formed upon CID-MS/MS of isobaric stable isotope labeled forms of the DMBNHS derivatized phosphopeptides. Under these conditions, the phosphate group stayed intact. Access for a greater number of peptides to provide enhanced phosphopeptide sequence identification and phosphorylation site characterization was achieved via automated data-dependent CID-MS3 or ETD-MS/MS analysis due to the formation of the higher charge state precursor ions. Importantly, improved sequence coverage was observed using ETD-MS/MS following introduction of the sulfonium ion fixed charge, but with no detrimental effects on ETD fragmentation efficiency. PMID:21952753

Quantitative determination of cucurbitane-type triterpenes and triterpene glycosides in dietary supplements containing bitter melon (Momordica charantia) by HPLC-MS/MS.

PubMed

Ma, Jun; Krynitsky, Alexander J; Grundel, Erich; Rader, Jeanne I

2012-01-01

Momordica charantia L. (Cucurbitaceae), commonly known as bitter melon, is widely cultivated in many tropical and subtropical areas of the world. It is a common food staple; its fruits, leaves, seeds, stems, and roots also have a long history of use in traditional medicine. In the United States, dietary supplements labeled as containing bitter melon can be purchased over-the-counter and from Internet suppliers. Currently, no quantitative analytical method is available for monitoring the content of cucurbitane-type triterpenes and triterpene glycosides, the major constituents of bitter melon, in such supplements. We investigated the use of HPLC-electrospray ionization (ESI)-MS/MS for the quantitative determination of such compounds in dietary supplements containing bitter melon. Values for each compound obtained from external calibration were compared with those obtained from the method of standard additions to address matrix effects associated with ESI. In addition, the cucurbitane-type triterpene and triterpene glycoside contents of two dietary supplements determined by the HPLC-ESI-MS/MS method with standard additions were compared with those measured by an HPLC method with evaporative light scattering detection, which was recently developed for quantification of such compounds in dried fruits of M. charantia. The contents of five cucurbitane-type triterpenes and triterpene glycosides in 10 dietary supplements were measured using the HPLC-ESI-MS/MS method with standard additions. The total contents of the five compounds ranged from 17 to 3464 microg/serving.

A Simple, Fast, Low Cost, HPLC/UV Validated Method for Determination of Flutamide: Application to Protein Binding Studies.

PubMed

Esmaeilzadeh, Sara; Valizadeh, Hadi; Zakeri-Milani, Parvin

2016-06-01

The main goal of this study was development of a reverse phase high performance liquid chromatography (RP-HPLC) method for flutamide quantitation which is applicable to protein binding studies. Ultrafilteration method was used for protein binding study of flutamide. For sample analysis, flutamide was extracted by a simple and low cost extraction method using diethyl ether and then was determined by HPLC/UV. Acetanilide was used as an internal standard. The chromatographic system consisted of a reversed-phase C8 column with C8 pre-column, and the mobile phase of a mixture of 29% (v/v) methanol, 38% (v/v) acetonitrile and 33% (v/v) potassium dihydrogen phosphate buffer (50 mM) with pH adjusted to 3.2. Acetanilide and flutamide were eluted at 1.8 and 2.9 min, respectively. The linearity of method was confirmed in the range of 62.5-16000 ng/ml (r(2) > 0.99). The limit of quantification was shown to be 62.5 ng/ml. Precision and accuracy ranges found to be (0.2-1.4%, 90-105%) and (0.2-5.3 %, 86.7-98.5 %) respectively. Acetanilide and flutamide capacity factor values of 1.35 and 2.87, tailing factor values of 1.24 and 1.07 and resolution values of 1.8 and 3.22 were obtained in accordance with ICH guidelines. Based on the obtained results a rapid, precise, accurate, sensitive and cost-effective analysis procedure was proposed for quantitative determination of flutamide.

A Simple, Fast, Low Cost, HPLC/UV Validated Method for Determination of Flutamide: Application to Protein Binding Studies

PubMed Central

Esmaeilzadeh, Sara; Valizadeh, Hadi; Zakeri-Milani, Parvin

2016-01-01

Purpose: The main goal of this study was development of a reverse phase high performance liquid chromatography (RP-HPLC) method for flutamide quantitation which is applicable to protein binding studies. Methods: Ultrafilteration method was used for protein binding study of flutamide. For sample analysis, flutamide was extracted by a simple and low cost extraction method using diethyl ether and then was determined by HPLC/UV. Acetanilide was used as an internal standard. The chromatographic system consisted of a reversed-phase C8 column with C8 pre-column, and the mobile phase of a mixture of 29% (v/v) methanol, 38% (v/v) acetonitrile and 33% (v/v) potassium dihydrogen phosphate buffer (50 mM) with pH adjusted to 3.2. Results: Acetanilide and flutamide were eluted at 1.8 and 2.9 min, respectively. The linearity of method was confirmed in the range of 62.5-16000 ng/ml (r2 > 0.99). The limit of quantification was shown to be 62.5 ng/ml. Precision and accuracy ranges found to be (0.2-1.4%, 90-105%) and (0.2-5.3 %, 86.7-98.5 %) respectively. Acetanilide and flutamide capacity factor values of 1.35 and 2.87, tailing factor values of 1.24 and 1.07 and resolution values of 1.8 and 3.22 were obtained in accordance with ICH guidelines. Conclusion: Based on the obtained results a rapid, precise, accurate, sensitive and cost-effective analysis procedure was proposed for quantitative determination of flutamide. PMID:27478788

Anion-exchange high-performance liquid chromatography with post-column detection for the analysis of phytic acid and other inositol phosphates

NASA Technical Reports Server (NTRS)

Rounds, M. A.; Nielsen, S. S.; Mitchell, C. A. (Principal Investigator)

1993-01-01

The use of gradient anion-exchange HPLC, with a simple post-column detection system, is described for the separation of myo-inositol phosphates, including "phytic acid" (myo-inositol hexaphosphate). Hexa-, penta-, tetra-, tri- and diphosphate members of this homologous series are clearly resolved within 30 min. This method should facilitate analysis and quantitation of "phytic acid" and other inositol phosphates in plant, food, and soil samples.

Component analysis of Iranian crack; a newly abused narcotic substance in iran.

PubMed

Farhoudian, Ali; Sadeghi, Mandana; Khoddami Vishteh, Hamid Reza; Moazen, Babak; Fekri, Monir; Rahimi Movaghar, Afarin

2014-01-01

Iranian crack is a new form of narcotic substance that has found widespread prevalence in Iran in the past years. Crack only nominally resembles crack cocaine as it is widely different in its clinical signs. Thus the present study aims to quantify the chemical combination of this drug. The samples included 18 specimen of Crack collected from different zones of Tehran, Iran. All specimens were in the form of inodorous cream solid powdery substance. TLC and HPLC methods were used to perform semi-quantitative and quantitative analysis of the components, respectively. The TLC analysis showed no cocaine compound in the specimens while they all revealed to contain heroin, codeine, morphine and caffeine. All but two specimens contained thebaine. None of the specimens contained amphetamine, benzodiazepines, tricyclic antidepressants, aspirin, barbiturates, tramadol and buprenorphine. Acetaminophen was found in four specimens. HPLC revealed heroin to be the foundation substance in all specimens and most of them contained a significant amount of acetylcodeine. The present analysis of the chemical combination of Crack showed that this substance is a heroin-based narcotic which is basically different from the cocaine-based crack used in Western countries. Studies like the present one at different time points, especially when abnormal clinical signs are detected, can reveal the chemical combination of the target substance and contribute to the clinical management of its acute or chronic poisoning.

[Analysis of phenylethanoid glycosides of Herba cistanchis by RP-HPLC].

PubMed

Tu, P F; Wang, B; Deyama, T; Zhang, Z G; Lou, Z C

1997-04-01

The Chinese drug "Rou Cong-rong" (Herba Cistanchis) is one of the commonly used drugs in Chinese traditional medicine. It is used to reinforce the vital function of kidney, especially that of the sexual organs and induce laxation, for the treatment of impotence, premature ejaculation in men, infertility, morbid leukorrhea, profuse metrorrhagia in women, and chronic constipation in the aged. This paper deals with the qualitative and quantitative analysis of phenylethanoid glycosides of four species and one variety of Genus Cistanche and 23 lots of commercial crude drugs of Herba Cistanchis by RP-HPLC. The results were as follows: the chemical constituents of Cistanche deserticola Ma, C. salsa (C. A. Mey) G. Beck, C. salsa var. albiflora P. F. Tu et Z. C. Lou and C. tubulosa were similar while those of C. sinensis were different from the others; the contents of echinacoside and acteoside of C. salsa, which were 2.13% and 1.51%, were the highest of the genus Cistanche. An ODS column (Alltima C18, 5 microns, 250 x 4.6 mm) was employed. Linear gradient elution of acetonitrile--1.5% acetic acid was used as mobile phase, and concentration of acetontrile was from 8% to 20% (0-60 min) in the qualitative analysis, and from 11.5 to 20% (0-35 min) in the quantitative analysis. The flow rate was 1.2 ml.min-1. The detection wavelength was set at 335 nm.

[Cerebral vasospasm and lipid peroxidation--lipid peroxides in the cerebrospinal fluid after subarachnoid hemorrhage].

PubMed

Sasaki, T; Asano, T; Takakura, K; Sano, K; Nakamura, T; Suzuki, N; Imabayashi, S; Ishikawa, Y

1982-12-01

The relationship between lipid peroxides in cerebrospinal fluid (CSF) and the occurrence of cerebral vasospasm following subarachnoid hemorrhage (SAH) was evaluated by analyzing CSF with high-performance liquid chromatography (HPLC) and gas chromatography mass spectrometry (GC-MS). Hydroperoxy eicosatetraenoic acids (HPETEs) and hydroxy eicosatetraenoic acids (HETEs) were synthesized by the treatment of arachidonic acid with hydrogen peroxide and cupric chloride. The retention time of these HPETEs and HETEs were determined on HPLC. The position of oxydation occurred was determined after methylation, reduction and trimethyl silylation using GC-MS. Thus the elucidation of positional isomers of HPETEs and HETEs was made possible by the retention time on HPLC. The supernant of CSF after SAH was adjusted to pH 3.0 and then absorbed to octadecyl silyl silica column. The eluted fraction with 15% ethanol-water from octadecyl silyl silica column was analyzed by HPLC detecting at 238 nm. No peak was observed on HPLC at the region of HPETEs and HETEs in the CSF obtained from healthy person. In SAH patients, several peaks were recognized in accordance with the occurrence of cerebral vasospasm. One of the peaks was identified as 5-HETE by HPLC and GC-MS. In 10 SAH patients, semi-quantitative analysis of 5-HETE in the CSF was performed by measuring the height of the peak identified as 5-HETE on HPLC. The close correlation was recognized between the occurrence of cerebral vasospasm and the appearance of 5-HETE in the CSF. The results of the present study suggest that lipid peroxidation is involved in the pathogenesis of chronic vasospasm after SAH.

Chemical fingerprinting and quantitative constituent analysis of Siwu decoction categorized formulae by UPLC-QTOF/MS/MS and HPLC-DAD

PubMed Central

2013-01-01

Background Siwu decoction categorized formulae (SWDCF) are widely used for treating gynecological diseases. This study aims to elucidate the differences of bioactive constituents in SWDCF by ultra-high performance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC - QTOF - MS /MS) and HPLC-DAD. Methods An efficient method based on UPLC - QTOF - MS /MS was developed for identifying the chemical profiles of SWDCF. HPLC-DAD method was used for quantifying seven chemical markers in SWDCF. Results Eighty four components were identified or characterized, including ten organic acids, thirty glycosides (monoterpene or iridoid or phenylpropanoids glycosides), fourteen lactones, eighteen flavonoids, and eleven alkaloids in the complex system. The datasets of tR-m/z pairs, ion intensities and sample codes were processed with supervised orthogonal partial least squared discriminant analysis to compare these decoction samples. After a clear classification was established, OPLS-DA was performed and 16 common components with relative quantity in SWDCF samples were determined. Gallic acid, protocatechuic acid, vanillic acid, caffeic acid, paeoniflorin, ferulic acid, and senkyunolide I were selected as the chemical markers to identify SWDCF by HPLC-DAD. Conclusion The chemical profiles with 84 components in SWDCF, including monoterpene glycosides, acetophenones, galloyl glucoses, even some isomers in the complex system were characterized by UPLC–QTOF–MS/MS. PMID:23453004

Quality Assessment of Kumu Injection, a Traditional Chinese Medicine Preparation, Using HPLC Combined with Chemometric Methods and Qualitative and Quantitative Analysis of Multiple Alkaloids by Single Marker.

PubMed

Wang, Ning; Li, Zhi-Yong; Zheng, Xiao-Li; Li, Qiao; Yang, Xin; Xu, Hui

2018-04-09

Kumu injection (KMI) is a common-used traditional Chinese medicine (TCM) preparation made from Picrasma quassioides (D. Don) Benn. rich in alkaloids. An innovative technique for quality assessment of KMI was developed using high performance liquid chromatography (HPLC) combined with chemometric methods and qualitative and quantitative analysis of multi-components by single marker (QAMS). Nigakinone (PQ-6, 5-hydroxy-4-methoxycanthin-6-one), one of the most abundant alkaloids responsible for the major pharmacological activities of Kumu, was used as a reference substance. Six alkaloids in KMI were quantified, including 6-hydroxy- β -carboline-1-carboxylic acid (PQ-1), 4,5-dimethoxycanthin-6-one (PQ-2), β -carboline-1-carboxylic acid (PQ-3), β -carboline-1-propanoic acid (PQ-4), 3-methylcanthin-5,6-dione (PQ-5), and PQ-6. Based on the outcomes of twenty batches of KMI samples, the contents of six alkaloids were used for further chemometric analysis. By hierarchical cluster analysis (HCA), radar plots, and principal component analysis (PCA), all the KMI samples could be categorized into three groups, which were closely related to production date and indicated the crucial influence of herbal raw material on end products of KMI. QAMS combined with chemometric analysis could accurately measure and clearly distinguish the different quality samples of KMI. Hence, QAMS is a feasible and promising method for the quality control of KMI.

Determination of salicylic acid by HPLC in plasma and saliva from children with juvenile chronic arthritis.

PubMed

Legaz, M E; Acitores, E; Valverde, F

1992-12-01

A high performance liquid chromatography (HPLC) method has been developed for measuring salicylic acid in the plasma and saliva of children with juvenile chronic arthritis (JCA). Samples were extracted with diethyl ether and, after drying, redissolved in methanol to be chromatographed. Quantitation of salicylic acid was performed by reverse phase HPLC on a spherisorb ODS-2 column, using methanol: water: acetic acid as mobile phase. Phenolic was monitored by absorbance at 237 nm. Linearity between the amount of mass injected and the response in the detector was determined. This method was applied to compare concentrations of salivary and plasma salicylic acid. The method also permitted the quantitation of salivary salicylate as a non-invasive, indirect method for monitoring the concentration of plasma salicylate in patients with JCA.

Determination of GABA and vigabatrin in human plasma by a rapid and simple HPLC method: correlation between clinical response to vigabatrin and increase in plasma GABA.

PubMed

Löscher, W; Fassbender, C P; Gram, L; Gramer, M; Hörstermann, D; Zahner, B; Stefan, H

1993-03-01

The novel antiepileptic drug vigabatrin (Sabril) acts by inhibiting degradation of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), increasing the GABA concentrations in the brain. Because the GABA degrading enzyme GABA aminotransferase (GABA-T) is also present in peripheral tissues, including blood platelets, measurement of plasma GABA levels might be a useful indication of the pharmacological response to vigabatrin during therapeutic monitoring. However, because of the very low concentrations of GABA in plasma, the few methods available for plasma GABA analysis are time-consuming, difficult to perform and/or not selective enough because of potential interference with other plasma constituents. In the present study, a rapid, selective and sensitive amino acid analysis HPLC method has been developed for plasma GABA determination with fluorescence detection, using o-phthaldialdehyde as a precolumn derivatizing agent. By employing a 3 microns particle size reversed-phase column and a multi-step gradient system of two solvents, the very low endogenous concentration of GABA in human plasma could be reproducibly quantitated without interference of other endogenous compounds. Incubation of human plasma samples with GABA degrading enzyme(s) resulted in an almost total loss of the GABA peak, thus demonstrating the specificity of the method for GABA analysis. In addition to GABA and other endogenous amino acids, the HPLC method could be used to quantitate plasma levels of vigabatrin. Thus, this improved HPLC amino acid assay might be used to examine whether concomitant monitoring of plasma GABA and vigabatrin is useful for clinical purposes. This was examined in 20 epileptic patients undergoing chronic treatment with vigabatrin. The average plasma GABA level of these 20 patients did not differ significantly from non-epileptic controls. However, when epileptic patients were subdivided according to their clinical response to vigabatrin, vigabatrin responders had significantly higher GABA levels than nonresponders or controls. In contrast to the difference in plasma GABA, vigabatrin responders and nonresponders did not differ in dose or plasma level of vigabatrin. These data may indicate that determination of plasma GABA is a valuable non-invasive method for therapeutic monitoring in patients on medication with vigabatrin.

Preliminary Phytochemical Screening, Quantitative Analysis of Alkaloids, and Antioxidant Activity of Crude Plant Extracts from Ephedra intermedia Indigenous to Balochistan.

PubMed

Gul, Rahman; Jan, Syed Umer; Faridullah, Syed; Sherani, Samiullah; Jahan, Nusrat

2017-01-01

The aim of this study was to evaluate the antioxidant activity, screening the phytogenic chemical compounds, and to assess the alkaloids present in the E. intermedia to prove its uses in Pakistani folk medicines for the treatment of asthma and bronchitis. Antioxidant activity was analyzed by using 2,2-diphenyl-1-picryl-hydrazyl-hydrate assay. Standard methods were used for the identification of cardiac glycosides, phenolic compounds, flavonoids, anthraquinones, and alkaloids. High performance liquid chromatography (HPLC) was used for quantitative purpose of ephedrine alkaloids in E. intermedia . The quantitative separation was confirmed on Shimadzu 10AVP column (Shampack) of internal diameter (id) 3.0 mm and 50 mm in length. The extract of the solute in flow rate of 1 ml/min at the wavelength 210 nm and methanolic extract showed the antioxidant activity and powerful oxygen free radicals scavenging activities and the IC50 for the E. intermedia plant was near to the reference standard ascorbic acid. The HPLC method was useful for the quantitative purpose of ephedrine (E) and pseudoephedrine (PE) used for 45 samples of one species collected from central habitat in three districts (Ziarat, Shairani, and Kalat) of Balochistan. Results showed that average alkaloid substance in E. intermedia was as follows: PE (0.209%, 0.238%, and 0.22%) and E (0.0538%, 0.0666%, and 0.0514%).

Reversed phase HPLC for strontium ranelate: Method development and validation applying experimental design.

PubMed

Kovács, Béla; Kántor, Lajos Kristóf; Croitoru, Mircea Dumitru; Kelemen, Éva Katalin; Obreja, Mona; Nagy, Előd Ernő; Székely-Szentmiklósi, Blanka; Gyéresi, Árpád

2018-06-01

A reverse-phase HPLC (RP-HPLC) method was developed for strontium ranelate using a full factorial, screening experimental design. The analytical procedure was validated according to international guidelines for linearity, selectivity, sensitivity, accuracy and precision. A separate experimental design was used to demonstrate the robustness of the method. Strontium ranelate was eluted at 4.4 minutes and showed no interference with the excipients used in the formulation, at 321 nm. The method is linear in the range of 20-320 μg mL-1 (R2 = 0.99998). Recovery, tested in the range of 40-120 μg mL-1, was found to be 96.1-102.1 %. Intra-day and intermediate precision RSDs ranged from 1.0-1.4 and 1.2-1.4 %, resp. The limit of detection and limit of quantitation were 0.06 and 0.20 μg mL-1, resp. The proposed technique is fast, cost-effective, reliable and reproducible, and is proposed for the routine analysis of strontium ranelate.

Physical-chemical and biological characterization of different preparations of equine chorionic gonadotropin

PubMed Central

Natal, Fabio Luis Nogueira; Ribela, Maria Teresa Carvalho Pinto; de Almeida, Beatriz Elane; de Oliveira, João Ezequiel; Bartolini, Paolo

2016-01-01

Ovarian stimulation with commercial preparations of equine chorionic gonadotropin (eCG) produces extremely variable responses in domestic animals, ranging from excessive stimulation to practically no stimulation, when applied on the basis of their declared unitage. This study was conducted to analyze four commercial preparations from different manufacturers via reversed-phase HPLC (RP-HPLC) in comparison with a reference preparation and an official International Standard from the World Health Organization. The peaks obtained by this qualitative and quantitative physical–chemical analysis were compared using an in vivo bioassay based on the ovarian weight gain of prepubertal female rats. The RP-HPLC data showed one or two peaks close to a main peak (tR = 27.9 min), which were related to the in vivo bioactivity. Commercial preparations that have this altered peak showed very little or no in vivo activity, as demonstrated by rat ovarian weight and in peripubertal gilts induced to ovulate. Overall, these findings indicate that RP-HPLC can be a rapid and reliable tool to reveal changes in the physicochemical profile of commercial eCG that is apparently related to decreased biological activity of this hormone. PMID:27297410

[Determination of cyclamate in complex matrix using HPLC after column derivatization with 4-fluoro-7-nitrobenzofurazan].

PubMed

Hauck, M; Köbler, H

1990-01-01

A method for the analysis of cyclamate in complex foodstuffs has been developed. This method is applicable in strongly coloured and protein-rich foodstuffs. The quantitative determination depends on oxidation of cyclamate to cyclohexylamine and derivatisation with 4-fluoro-7-nitrobenzofuran (NBD-F). The derivatives are analysed by HPLC on a C18: reversed-phase column, their minimal stability being 12 h. There are two possible methods of detection: (a) absorbance at 485 nm and (b) fluorescence with excitation at 485 nm and emission at 530 nm. The detection limit of cyclamate is 5 mg/kg foodstuff, with fluorescence detection 0.4 mg/kg. The recoveries are in the range of 88% to 104%.

Identification of procyanidins in cocoa (Theobroma cacao) and chocolate using high-performance liquid chromatography/mass spectrometry.

PubMed

Hammerstone, J F; Lazarus, S A; Mitchell, A E; Rucker, R; Schmitz, H H

1999-02-01

Monomeric and oligomeric procyanidins present in cocoa and chocolate were separated and identified using a modified normal-phase high-performance liquid chromatography (HPLC) method coupled with on-line mass spectrometry (MS) analysis using an atmospheric pressure ionization electrospray chamber. The chromatographic separation was achieved using a silica stationary phase in combination with a gradient ascending in polarity. This qualitative report confirms the presence of a complex series of procyanidins in raw cocoa and certain chocolates using HPLC/MS techniques. Although both cocoa and chocolate contained monomeric and oligomeric procyanidin units 2-10, only use of negative mode provided MS data for the higher oligomers (i.e., >pentamer). Application of this method for qualitative analysis of proanthocyanidins in other food products and confirmation of this method as a reliable quantitative tool for determining levels of procyanidins in cocoa, chocolate, and other food products are currently being investigated.

Classification of 'Chemlali' accessions according to the geographical area using chemometric methods of phenolic profiles analysed by HPLC-ESI-TOF-MS.

PubMed

Taamalli, Amani; Arráez Román, David; Zarrouk, Mokhtar; Segura-Carretero, Antonio; Fernández-Gutiérrez, Alberto

2012-05-01

The present work describes a classification method of Tunisian 'Chemlali' olive oils based on their phenolic composition and geographical area. For this purpose, the data obtained by HPLC-ESI-TOF-MS from 13 samples of extra virgin olive oils, obtained from different production area throughout the country, were used for this study focusing in 23 phenolics compounds detected. The quantitative results showed a significant variability among the analysed oil samples. Factor analysis method using principal component was applied to the data in order to reduce the number of factors which explain the variability of the selected compounds. The data matrix constructed was subjected to a canonical discriminant analysis (CDA) in order to classify the oil samples. These results showed that 100% of cross-validated original group cases were correctly classified, which proves the usefulness of the selected variables. Copyright © 2011 Elsevier Ltd. All rights reserved.

Polysaccharide Constituents of Three Types of Sea Urchin Shells and Their Anti-Inflammatory Activities

PubMed Central

Jiao, Heng; Shang, Xiaohui; Dong, Qi; Wang, Shuang; Liu, Xiaoyu; Zheng, Heng; Lu, Xiaoling

2015-01-01

As a source of potent anti-inflammatory traditional medicines, the quantitative chromatographic fingerprints of sea urchin shell polysaccharides were well established via pre-column derivatization high performance liquid chromatography (HPLC) analysis. Based on the quantitative results, the content of fucose and glucose could be used as preliminary distinguishing indicators among three sea urchin shell species. Besides, the anti-inflammatory activities of the polysaccharides from sea urchin shells and their gonads were also determined. The gonad polysaccharide of Anthocidaris crassispina showed the most potent anti-inflammatory activity among all samples tested. PMID:26389925

Polysaccharide Constituents of Three Types of Sea Urchin Shells and Their Anti-Inflammatory Activities.

PubMed

Jiao, Heng; Shang, Xiaohui; Dong, Qi; Wang, Shuang; Liu, Xiaoyu; Zheng, Heng; Lu, Xiaoling

2015-09-16

As a source of potent anti-inflammatory traditional medicines, the quantitative chromatographic fingerprints of sea urchin shell polysaccharides were well established via pre-column derivatization high performance liquid chromatography (HPLC) analysis. Based on the quantitative results, the content of fucose and glucose could be used as preliminary distinguishing indicators among three sea urchin shell species. Besides, the anti-inflammatory activities of the polysaccharides from sea urchin shells and their gonads were also determined. The gonad polysaccharide of Anthocidaris crassispina showed the most potent anti-inflammatory activity among all samples tested.

Quantitative analysis of pyroglutamic acid in peptides.

PubMed

Suzuki, Y; Motoi, H; Sato, K

1999-08-01

A simplified and rapid procedure for the determination of pyroglutamic acid in peptides was developed. The method involves the enzymatic cleavage of an N-terminal pyroglutamate residue using a thermostable pyroglutamate aminopeptidase and isocratic HPLC separation of the resulting enzymatic hydrolysate using a column switching technique. Pyroglutamate aminopeptidase from a thermophilic archaebacteria, Pyrococcus furiosus, cleaves N-terminal pyroglutamic acid residue independent of the molecular weight of the substrate. It cleaves more than 85% of pyroglutamate from peptides whose molecular weight ranges from 362.4 to 4599.4 Da. Thus, a new method is presented that quantitatively estimates N-terminal pyroglutamic acid residue in peptides.

Fractionation of secondary metabolites of orange (Citrus sinensis L.) leaves by fast centrifugal partition chromatography

USDA-ARS?s Scientific Manuscript database

Conventional HPLC provides ready detection of the major phenolic compounds in methanol extracts of orange leaves, yet conventional HPLC also shows the presence of many more compounds, to an extent where extensive peak overlap prevents distinct peak detection and reliable quantitation. A more complet...

Development of a HPLC-UV method for the quantitative determination of four short-chain fatty acids and lactic acid produced by intestinal bacteria during in vitro fermentation.

PubMed

De Baere, S; Eeckhaut, V; Steppe, M; De Maesschalck, C; De Backer, P; Van Immerseel, F; Croubels, S

2013-06-01

A rapid and sensitive HPLC-UV method for the quantitative determination of four short-chain fatty acids (SCFAs) and lactic acid (LA) produced during in vitro fermentation is presented. Extraction of SCFAs from supernatants of bacterial cultures is aggravated due to their polarity and volatility. Detection can only be performed at a short, non-selective UV wavelength (210nm), due to the lack of any significant chromophore. Therefore special attention was paid to the optimization of the sample preparation procedure and the HPLC-UV conditions. The final extraction procedure consisted of a liquid-liquid back extraction using diethylether. Prior to HPLC-UV analysis the samples were acidified (pH<2) in order to improve retention of the SCFA's and LA on the Hypersil Gold aQ column. Matrix-matched calibration graphs were prepared for all analytes of interest (range 0.5-50mM) and correlation and goodness-of-fit coefficients were between 0.9951-0.9993 and 3.88-8.27%, respectively. Limits of detection and quantification ranged from 0.13 to 0.33mM and 0.5 to 1.0mM, respectively. The results for the within-day and between-day precision and accuracy fell within the ranges specified. The reported validated method has been successfully used for the in vitro screening of supernatants of bacterial cultures for the presence of butyric acid, aiming to select for butyric acid-producing bacteria. In addition, the method has been used to determine the production pattern of selected fatty acids by bacterial species isolated from human feces and chicken caeca. Copyright © 2013 Elsevier B.V. All rights reserved.

Quantitative isomer-specific N-glycan fingerprinting using isotope coded labeling and high performance liquid chromatography-electrospray ionization-mass spectrometry with graphitic carbon stationary phase.

PubMed

Michael, Claudia; Rizzi, Andreas M

2015-02-27

Glycan reductive isotope labeling (GRIL) using (12)C6-/(13)C6-aniline as labeling reagent is reported with the aim of quantitative N-glycan fingerprinting. Porous graphitized carbon (PGC) as stationary phase in capillary scale HPLC coupled to electrospray mass spectrometry with time of flight analyzer was applied for the determination of labeled N-glycans released from glycoproteins. The main benefit of using stable isotope-coding in the context of comparative glycomics lies in the improved accuracy and precision of the quantitative analysis in combined samples and in the potential of correcting for structure-dependent incomplete enzymatic release of oligosaccharides when comparing identical target proteins. The method was validated with respect to mobile phase parameters, reproducibility, accuracy, linearity and limit of detection/quantification (LOD/LOQ) using test glycoproteins. It is shown that the developed method is capable of determining relative amounts of N-glycans (including isomers) comparing two samples in one single HPLC-MS run. The analytical potential and usefulness of GRIL in combination with PGC-ESI-TOF-MS is demonstrated comparing glycosylation in human monoclonal antibodies produced in Chinese hamster ovary cells (CHO) and hybridoma cell lines. Copyright © 2015 Elsevier B.V. All rights reserved.

Quantitative determination of limonin in citrus juices by HPLC using computerized solvent optimization.

PubMed

Shaw, P E; Wilson, C W

1988-09-01

The commercially available computer program, Drylab, for optimization of separations by high-performance liquid chromatography (HPLC) using binary solvent mixtures is used to improve an HPLC method for separation of the bitter principle, limonin, in grapefruit and navel orange juices. Best conditions for separation of limonin in a reasonable time are 30 to 32% acetonitrile in water at 0.9 mL/min using a 5-micron C18 column 10 cm long. These conditions are used to analyze grapefruit and navel orange juice samples, and these HPLC results are compared with values determined by enzyme immunoassay or thin-layer chromatography (TLC) on the same samples.

Rapid simultaneous determination of isoflavones in Radix puerariae using high-performance liquid chromatography-triple quadrupole mass spectrometry with novel shell-type column.

PubMed

Du, Gang; Zhao, Haiyu; Song, Yuelin; Zhang, Qingwen; Wang, Yitao

2011-10-01

A high-performance liquid chromatography (HPLC) coupled with triple quadrupole mass spectrometry (MS/MS) method was developed for rapid determination of 13 isoflavones in Radix puerariae. A novel shell-type column, namely Kinetex core-shell C(18) column (50 mm×2.1 mm id, 2.6 μm), and gradient elution were used during the analysis. The chromatographic peaks of 13 investigated compounds were identified by comparing their retention time and MS data with the related reference compounds. Multiple-reaction monitoring (MRM) was employed for the quantitative analysis with negative ionization mode. All calibration curves showed good linearity (r(2)>0.9990) within test ranges. The LOD and LOQ were lower than 0.017 and 0.873 μg/mL on column, respectively. The intra- and inter-day precisions for 13 analytes were <1.17 and 2.17%, respectively, and the recoveries were 93.1-104.4%. The validated method was applied for quantitative analysis of 13 isoflavones in 7 species of Radix puerariae. The result demonstrated that HPLC-MS/MS system with Kinetex column could be a promising analytical tool for the determination of isoflavones in traditional Chinese medicines, which is helpful for comprehensive evaluation of quality of R. puerariae. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Quantitative analysis of ginger components in commercial products using liquid chromatography with electrochemical array detection

PubMed Central

Shao, Xi; Lv, Lishuang; Parks, Tiffany; Wu, Hou; Ho, Chi-Tang; Sang, Shengmin

2010-01-01

For the first time, a sensitive reversed-phase HPLC electrochemical array method has been developed for the quantitative analysis of eight major ginger components ([6]-, [8]-, and [10]-gingerol, [6]-, [8]-, and [10]-shogaol, [6]-paradol, and [1]-dehydrogingerdione) in eleven ginger-containing commercial products. This method was valid with unrivaled sensitivity as low as 7.3 – 20.2 pg of limit of detection and a range of 14.5 to 40.4 pg of limit of quantification. Using this method, we quantified the levels of eight ginger components in eleven different commercial products. Our results found that both levels and ratios among the eight compounds vary greatly in commercial products. PMID:21090746

A Simple and Rapid HPLC-PDA MS Method for the Profiling of Citrus Peels and Traditional Italian Liquors.

PubMed

Guccione, Clizia; Bergonzi, Maria Camilla; Piazzini, Vieri; Bilia, Anna Rita

2016-07-01

A chromatographic method for the qualitative and quantitative characterization of peels and preparations based on different species of Citrus was developed in order to obtain a complete profile of the constituents, including flavonoids and protoalkaloids. Commercial peels of sweet orange, lemon, mandarin, and grapefruit were analyzed. Seventeen constituents including flavanones, flavones, polymethoxyflavones, and protoalkaloids were identified by HPLC-PDA, HPLC-MS, and HPLC-MS/MS using a comparison of retention times and UV-Vis and MS spectra with reference standards and literature data. The total amount of flavanones [neoeriocitrin (5), naringin (8) and hesperidin (9)] and polymethoxflavones [sinensetin (12), nobiletin (14), 3,5,6,7,8,3',4'-heptamethoxyflavone (15), and tangeretin (16)] was determined and expressed as naringin (8) or hesperidin (9), and sinensetin (12), respectively. The protoalkaloid synephrine was detected in all samples, except in grapefruit, but its content was lower than the limit of quantification. Qualitative and quantitative chemical profiles of three different Italian aromatic liquors ("Limoncello", "Arancello", and "Mandarinetto"), prepared according to traditional recipes, were also analyzed. Georg Thieme Verlag KG Stuttgart · New York.

Validation of HPLC method for the simultaneous and quantitative determination of 12 UV-filters in cosmetics.

PubMed

Nyeborg, M; Pissavini, M; Lemasson, Y; Doucet, O

2010-02-01

The aim of the study was the validation of a high-performance liquid chromatography (HPLC) method for the simultaneous and quantitative determination of twelve commonly used organic UV-filters (phenylbenzimidazole sulfonic acid, benzophenone-3, isoamyl p-methoxycinnamate, diethylamino hydroxybenzoyl hexyl benzoate, octocrylene, ethylhexyl methoxycinnamate, ethylhexyl salicylate, butyl methoxydibenzoylmethane, diethylhexyl butamido triazone, ethylhexyl triazone, methylene bis-benzotriazolyl tetramethylbutylphenol and bis-ethylhexyloxyphenol methoxyphenyl triazine) contained in suncare products. The separation and quantitative determination was performed in <30 min, using a Symmetry Shield(R) C18 (5 microm) column from Waters and a mobile phase (gradient mode) consisting of ethanol and acidified water. UV measurements were carried out at multi-wavelengths, according to the absorption of the analytes.

Development of a high performance liquid chromatography method and a liquid chromatography-tandem mass spectrometry method with the pressurized liquid extraction for the quantification and confirmation of sulfonamides in the foods of animal origin.

PubMed

Yu, Huan; Tao, Yanfei; Chen, Dongmei; Wang, Yulian; Huang, Lingli; Peng, Dapeng; Dai, Menghong; Liu, Zhenli; Wang, Xu; Yuan, Zonghui

2011-09-01

The residues of sulfonamides (SAs) in the foods of animal origin are of the major concern because they are harmful to the consumer's health and could induce pathogens to develop resistance. Rapid and efficient determination methods are urgently in need. A quantitative high performance liquid chromatography method (HPLC) and a confirmative liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the simultaneous determination of 18 sulfonamides such as sulfamidinum, sulfanilamide, sulfisomidine, sulfadiazine, sulfapyridine, sulfathiazole, sulfamerazine, sulfadimidine, sulfamethoxypyridazine, sulfamethoxydiazine, sulfisoxazole, sulfachloropyridazine, sulfamethoxazole, sulfamonomethoxine, sulfadoxine, sulfaclozine, sulfadimethoxine, sulfaquinoxaline in the muscles, livers and kidneys of swine, bovine and chicken were developed and validated. The sample preparation procedures included a pressurized liquid extraction (PLE) with acetonitrile conducted at elevated temperature (70°C) and pressure (1400 psi). After clean-up with hydrophilic-lipophilic balance cartridge, the extraction solution was concentrated and analyzed by HPLC and LC-MS/MS analysis. 18 SAs were separated by the HPLC with a Zorbax SB-Aq-C18 column and the mobile phase of methanol/acetonitrile/1% acetic acid with a gradient system. The wavelength of UV for the HPLC detection was set at 285 nm. The LC-MS/MS analysis was achieved with a Hypersil Golden column and the mobile phase of acetonitrile and 0.1% formic acid aqueous solution with two gradient systems. The Limits of detection (LOD) and the limits of quantitation (LOQ) were 3 μg/kg and 10 μg/kg, respectively, for both of the HPLC and LC-MS/MS. Linearity was obtained with an average coefficient of determination (R) higher than 0.9980 over a dynamic range from the LOQ value up to 5000 μg/kg. The recoveries of the methods range from 71.1% to 118.3% with the relative standard derivation less than 13%. The peaks of interest with no interferences were observed throughout the chromatographic run. The sample pretreatment provided efficient extraction and cleanup that enables a sensitive and rugged determination of 18 SAs, the obtained results revealed that PLE, in comparison with other sample preparation methods applied, has significantly higher efficacy for SAs isolation from animal tissues. Copyright © 2011 Elsevier B.V. All rights reserved.

Home-made online hyphenation of pressurized liquid extraction, turbulent flow chromatography, and high performance liquid chromatography, Cistanche deserticola as a case study.

PubMed

Song, Qingqing; Li, Jun; Liu, Xiao; Zhang, Yuan; Guo, Liping; Jiang, Yong; Song, Yuelin; Tu, Pengfei

2016-03-18

Incompatibility between the conventional pressurized liquid extraction (PLE) devices and high performance liquid chromatography (HPLC) extensively hinders direct and green chemical analysis of herbal materials. Herein, a facile PLE module was configured, and then it was online hyphenated with HPLC via a turbulent flow chromatography (TFC) column. Regarding PLE module, a long PEEK tube (0.13 × 1000 mm) was employed to generate desired pressure (approximately 13.0 MPa) when warm acidic water (70 °C) was delivered as extraction solvent at a high flow rate (2.5 mL/min), and a hollow guard column (3.0 × 4.0 mm) was implemented to hold crude materials. Effluent was collected from the outlet of PEEK tube, concentrated, and subjected onto HPLC coupled with hybrid ion trap-time of flight mass spectrometer to assess the extraction efficiency and also to profile the chemical composition of Cistanche deserticola (CD) that is honored as "Ginseng of the desert". Afterwards, a TFC column was introduced to accomplish online transmission of low molecule weight components from PLE module to HPLC coupled with diode array detection, and two electronic 6-port/2-channel valves were in charge of alternating the whole system between extraction (0-3.0 min) and elution (3.0-35.0 min) phases. Quantitative method was developed and validated for simultaneous determination of eight primary phenylethanoid glycosides in CD using online PLE-TFC-HPLC. All findings demonstrated that the home-made platform is advantageous at direct chemical analysis, as well as time-, solvent-, and material-savings, suggesting a robust tool for chemical fingerprinting of herbs. Copyright © 2016 Elsevier B.V. All rights reserved.

HPLC analysis and standardization of Brahmi vati – An Ayurvedic poly-herbal formulation

PubMed Central

Mishra, Amrita; Mishra, Arun K.; Tiwari, Om Prakash; Jha, Shivesh

2013-01-01

Objectives The aim of the present study was to standardize Brahmi vati (BV) by simultaneous quantitative estimation of Bacoside A3 and Piperine adopting HPLC–UV method. BV very important Ayurvedic polyherbo formulation used to treat epilepsy and mental disorders containing thirty eight ingredients including Bacopa monnieri L. and Piper longum L. Materials and methods An HPLC–UV method was developed for the standardization of BV in light of simultaneous quantitative estimation of Bacoside A3 and Piperine, the major constituents of B. monnieri L. and P. longum L. respectively. The developed method was validated on parameters including linearity, precision, accuracy and robustness. Results The HPLC analysis showed significant increase in amount of Bacoside A3 and Piperine in the in-house sample of BV when compared with all three different marketed samples of the same. Results showed variations in the amount of Bacoside A3 and Piperine in different samples which indicate non-uniformity in their quality which will lead to difference in their therapeutic effects. Conclusion The outcome of the present investigation underlines the importance of standardization of Ayurvedic formulations. The developed method may be further used to standardize other samples of BV or other formulations containing Bacoside A3 and Piperine. PMID:24396246

Qualitative and quantitative analysis of the saponins in Panax notoginseng leaves using ultra-performance liquid chromatography coupled with time-of-flight tandem mass spectrometry and high performance liquid chromatography coupled with UV detector.

PubMed

Liu, Fang; Ma, Ni; He, Chengwei; Hu, Yuanjia; Li, Peng; Chen, Meiwan; Su, Huanxing; Wan, Jian-Bo

2018-04-01

Panax notoginseng leaves (PNL) exhibit extensive activities, but few analytical methods have been established to exclusively determine the dammarane triterpene saponins in PNL. Ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC/Q-TOF MS) and HPLC-UV methods were developed for the qualitative and quantitative analysis of ginsenosides in PNL, respectively. Extraction conditions, including solvents and extraction methods, were optimized, which showed that ginsenosides Rc and Rb3, the main components of PNL, are transformed to notoginsenosides Fe and Fd, respectively, in the presence of water, by removing a glucose residue from position C-3 via possible enzymatic hydrolysis. A total of 57 saponins were identified in the methanolic extract of PNL by UPLC/Q-TOF MS. Among them, 19 components were unambiguously characterized by their reference substances. Additionally, seven saponins of PNL-ginsenosides Rb1, Rc, Rb2, and Rb3, and notoginsenosides Fc, Fe, and Fd-were quantified using the HPLC-UV method after extraction with methanol. The separation of analytes, particularly the separation of notoginsenoside Fc and ginsenoside Rc, was achieved on a Zorbax ODS C8 column at a temperature of 35°C. This developed HPLC-UV method provides an adequate linearity ( r 2  > 0.999), repeatability (relative standard deviation, RSD < 2.98%), and inter- and intraday variations (RSD < 4.40%) with recovery (98.7-106.1%) of seven saponins concerned. This validated method was also conducted to determine seven components in 10 batches of PNL. These findings are beneficial to the quality control of PNL and its relevant products.

Simultaneous qualitative and quantitative determination of phenolic compounds in Aloe barbadensis Mill by liquid chromatography-mass spectrometry-ion trap-time-of-flight and high performance liquid chromatography-diode array detector.

PubMed

Wu, Xiaofang; Ding, Wenjing; Zhong, Jiasheng; Wan, Jinzhi; Xie, Zhiyong

2013-06-01

An effective and comprehensive method was developed for the simultaneous analysis of phenolic compounds in the dried exudate of Aloe barbadensis Mill by liquid chromatography-mass spectrometry-ion trap-time-of-flight (LCMS-IT-TOF) and high performance liquid chromatography-diode array detector (HPLC-DAD). Qualitative analysis of all the compounds presented in A. barbadensis Mill was performed on LCMS-IT-TOF, and the diagnostic fragmentation patterns of different types of phenolic compounds (chromones, phenyl pyrones, naphthalene derivative, anthrones and anthraquinones) were discussed on the basis of ESI-IT-TOF MS of components in A. barbadensis Mill and eleven authentic standards. Under the optimal HPLC-DAD chromatographic conditions, quantification of 11 typical phenolic compounds in 15 batches of A. barbadensis Mill was achieved on an Agilent TC-C18 column using gradient elution with a solvent system of methanol and water at a flow rate of 1.0mLmin(-1) and detected at 230nm. All calibration curves exhibited good linear relationship (r(2)>0.9991). The relative standard deviation values for intraday precision were less than 2% with accuracies between 98.21% and 104.57%. The recoveries of the eleven analytes ranged from 97.53 to 105.00% with RSDs less than 2%. This is the first simultaneous characterization and quantitative determination of multiple phenolic compounds in A. barbadensis Mill from locally grown cultivars in China by LCMS-IT-TOF and HPLC-DAD, which can be applied to standardize the quality of A. barbadensis Mill and the future design of nutraceutical and cosmetic preparations. Copyright © 2013 Elsevier B.V. All rights reserved.

Stability indicating HPLC-DAD method for analysis of Ketorolac binary and ternary mixtures in eye drops: Quantitative analysis in rabbit aqueous humor.

PubMed

El Yazbi, Fawzy A; Hassan, Ekram M; Khamis, Essam F; Ragab, Marwa A A; Hamdy, Mohamed M A

2017-11-15

Ketorolac tromethamine (KTC) with phenylephrine hydrochloride (PHE) binary mixture (mixture 1) and their ternary mixture with chlorpheniramine maleate (CPM) (mixture 2) were analyzed using a validated HPLC-DAD method. The developed method was suitable for the in vitro as well as quantitative analysis of the targeted mixtures in rabbit aqueous humor. The analysis in dosage form (eye drops) was a stability indicating one at which drugs were separated from possible degradation products arising from different stress conditions (in vitro analysis). For analysis in aqueous humor, Guaifenesin (GUF) was used as internal standard and the method was validated according to FDA regulation for analysis in biological fluids. Agilent 5 HC-C18(2) 150×4.6mm was used as stationary phase with a gradient eluting solvent of 20mM phosphate buffer pH 4.6 containing 0.2% triethylamine and acetonitrile. The drugs were resolved with retention times of 2.41, 5.26, 7.92 and 9.64min for PHE, GUF, KTC and CPM, respectively. The method was sensitive and selective to analyze simultaneously the three drugs in presence of possible forced degradation products and dosage form excipients (in vitro analysis) and also with the internal standard, in presence of aqueous humor interferences (analysis in biological fluid), at a single wavelength (261nm). No extraction procedure was required for analysis in aqueous humor. The simplicity of the method emphasizes its capability to analyze the drugs in vivo (in rabbit aqueous humor) and in vitro (in pharmaceutical formulations). Copyright © 2017 Elsevier B.V. All rights reserved.

Determination of thiopurine S-methyltransferase activity by hydrophilic interaction liquid chromatography hyphenated with mass spectrometry.

PubMed

Pecher, Daniel; Dokupilová, Svetlana; Zelinková, Zuzana; Peppelenbosch, Maikel; Mikušová, Veronika; Mikuš, Peter

2017-08-05

Thiopurine S-methyltransferase (TPMT) plays an important role in the metabolism of thiopurines used in the therapy of inflammatory bowel diseases (IBD). In this work a new progressive method for the determination of TPMT activity in red blood cells lysates was developed. Analysis was carried out by means of hydrophilic interaction liquid chromatography (HILIC) hyphenated with mass spectrometry (MS). In comparison with reversed-phase high-performance liquid chromatography (RP-HPLC), that has been typically applied in determination of TPMT activity, the HILIC significantly improved the analytical signal provided by MS, shortened analysis time, and improved chromatographic resolution. The HILIC-HPLC-MS method was optimized and validated, providing favorable parameters of detection and quantitation limits (5.5 and 16.5pmol/mL, respectively), linearity (coefficient of determination 0.9999 in the range of 0.01-1.0nmol/mL), recovery and precision (93.25-100.37% with RSD 1.06-1.32% in the whole concentration range of QC samples). Moreover, in contrast to the conventional RP-HPLC-UV approach, the complex phenotype TPMT profiles can be reliably and without interferences monitored using the HILIC-HPLC-MS method. Such advanced monitoring can provide valuable detail information on the thiopurines (e.g. evaluating ratio of methylated and non-methylated 6-mercaptopurine) and, by that, TPMT action in biological systems before and during the therapy of IBD. Copyright © 2017 Elsevier B.V. All rights reserved.

Frontally eluted components procedure with thin layer chromatography as a mode of sample preparation for high performance liquid chromatography quantitation of acetaminophen in biological matrix.

PubMed

Klimek-Turek, A; Sikora, M; Rybicki, M; Dzido, T H

2016-03-04

A new concept of using thin-layer chromatography to sample preparation for the quantitative determination of solute/s followed by instrumental techniques is presented Thin-layer chromatography (TLC) is used to completely separate acetaminophen and its internal standard from other components (matrix) and to form a single spot/zone containing them at the solvent front position (after the final stage of the thin-layer chromatogram development). The location of the analytes and internal standard in the solvent front zone allows their easy extraction followed by quantitation by HPLC. The exctraction procedure of the solute/s and internal standard can proceed from whole solute frontal zone or its part without lowering in accuracy of quantitative analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

Quantitative analysis of PEG-functionalized colloidal gold nanoparticles using charged aerosol detection.

PubMed

Smith, Mackensie C; Crist, Rachael M; Clogston, Jeffrey D; McNeil, Scott E

2015-05-01

Surface characteristics of a nanoparticle, such as functionalization with polyethylene glycol (PEG), are critical to understand and achieve optimal biocompatibility. Routine physicochemical characterization such as UV-vis spectroscopy (for gold nanoparticles), dynamic light scattering, and zeta potential are commonly used to assess the presence of PEG. However, these techniques are merely qualitative and are not sensitive enough to distinguish differences in PEG quantity, density, or presentation. As an alternative, two methods are described here which allow for quantitative measurement of PEG on PEGylated gold nanoparticles. The first, a displacement method, utilizes dithiothreitol to displace PEG from the gold surface. The dithiothreitol-coated gold nanoparticles are separated from the mixture via centrifugation, and the excess dithiothreitol and dissociated PEG are separated through reversed-phase high-performance liquid chromatography (RP-HPLC). The second, a dissolution method, utilizes potassium cyanide to dissolve the gold nanoparticles and liberate PEG. Excess CN(-), Au(CN)2 (-), and free PEG are separated using RP-HPLC. In both techniques, the free PEG can be quantified against a standard curve using charged aerosol detection. The displacement and dissolution methods are validated here using 2-, 5-, 10-, and 20-kDa PEGylated 30-nm colloidal gold nanoparticles. Further value in these techniques is demonstrated not only by quantitating the total PEG fraction but also by being able to be adapted to quantitate the free unbound PEG and the bound PEG fractions. This is an important distinction, as differences in the bound and unbound PEG fractions can affect biocompatibility, which would not be detected in techniques that only quantitate the total PEG fraction.

Rapid method for measuring rotenone in water at piscicidal concentrations

USGS Publications Warehouse

Dawson, V.K.; Harman, P.D.; Schultz, D.P.; Allen, J.L.

1983-01-01

A high-performance liquid chromatography (HPLC) procedure that is rapid, specific, and sensitive (limit of detection <0.005 mg/liter) was developed for monitoring application and degradation rates of rotenone. For analysis, a water sample is buffered to pH 5 and injected through a Sep Pak(R) C18 disposable cartridge. The cartridge adsorbs and retains the rotenone which then can be eluted quantitatively from the cartridge with a small volume of methanol. This step effectively concentrates the sample and provides sample cleanup. The methanol extract is analyzed directly by HPLC on an MCH 10 reverse-phase column; methanol: water (75:25, volume : volume) is the mobile phase and flow rate is 1.5 ml/minute. The rotenone is detected by ultraviolet spectrophotometry at a wavelength of 295 nm.

High-throughput quantification for a drug mixture in rat plasma-a comparison of Ultra Performance liquid chromatography/tandem mass spectrometry with high-performance liquid chromatography/tandem mass spectrometry.

PubMed

Yu, Kate; Little, David; Plumb, Rob; Smith, Brian

2006-01-01

A quantitative Ultra Performance liquid chromatography/tandem mass spectrometry (UPL/MS/MS) protocol was developed for a five-compound mixture in rat plasma. A similar high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) quantification protocol was developed for comparison purposes. Among the five test compounds, three preferred positive electrospray ionization (ESI) and two preferred negative ESI. As a result, both UPLC/MS/MS and HPLC/MS/MS analyses were performed by having the mass spectrometer collecting ESI multiple reaction monitoring (MRM) data in both positive and negative ion modes during a single injection. Peak widths for most standards were 4.8 s for the HPLC analysis and 2.4 s for the UPLC analysis. There were 17 to 20 data points obtained for each of the LC peaks. Compared with the HPLC/MS/MS method, the UPLC/MS/MS method offered 3-fold decrease in retention time, up to 10-fold increase in detected peak height, with 2-fold decrease in peak width. Limits of quantification (LOQs) for both HPLC and UPLC methods were evaluated. For UPLC/MS/MS analysis, a linear range up to four orders of magnitude was obtained with r2 values ranging from 0.991 to 0.998. The LOQs for the five analytes ranged from 0.08 to 9.85 ng/mL. Three levels of quality control (QC) samples were analyzed. For the UPLC/MS/MS protocol, the percent relative standard deviation (RSD%) for low QC (2 ng/mL) ranged from 3.42 to 8.67% (N = 18). The carryover of the UPLC/MS/MS protocol was negligible and the robustness of the UPLC/MS/MS system was evaluated with up to 963 QC injections. Copyright 2006 John Wiley & Sons, Ltd.

Validation of a method for the quantitation of ghrelin and unacylated ghrelin by HPLC.

PubMed

Staes, Edith; Rozet, Eric; Ucakar, Bernard; Hubert, Philippe; Préat, Véronique

2010-02-05

An HPLC/UV method was first optimized for the separation and quantitation of human acylated and unacylated (or des-acyl) ghrelin from aqueous solutions. This method was validated by an original approach using accuracy profiles based on tolerance intervals for the total error measurement. The concentration range that achieved adequate accuracy extended from 1.85 to 59.30microM and 1.93 to 61.60microM for acylated and unacylated ghrelin, respectively. Then, optimal temperature, pH and buffer for sample storage were determined. Unacylated ghrelin was found to be stable in all conditions tested. At 37 degrees C acylated ghrelin was stable at pH 4 but unstable at pH 7.4, the main degradation product was unacylated ghrelin. Finally, this validated HPLC/UV method was used to evaluate the binding of acylated and unacylated ghrelin to liposomes.

Flavonoids and biflavonoids in Tuscan berries of Juniperus communis L.: detection and quantitation by HPLC/DAD/ESI/MS.

PubMed

Innocenti, Marzia; Michelozzi, Marco; Giaccherini, Catia; Ieri, Francesca; Vincieri, Franco Francesco; Mulinacci, Nadia

2007-08-08

The aim of the present work was to develop a quali-quantitative investigation, using HPLC/DAD and HPLC/ESI/MS techniques, of the phenolic composition of berries collected from wild Tuscan plants of Juniperus communis L. and grown in three different geographical zones. The applied chromatographic elution method made it possible to well separate up to 16 different compounds belonging to flavonoids, such as isoscutellarein and 8-hydroxyluteolin or hypolaetin glycosides, and six biflavonoids, among them amentoflavone, hynokiflavone, cupressoflavone, and methyl-biflavones. To the best of the authors' knowledge this is the first report on the presence of these compounds in juniper berries. The flavonoidic content in the analyzed berries ranged between 1.46 and 3.79 mg/g of fresh pulp, whereas the amount of the biflavonoids was always lower, varying between 0.14 and 1.38 mg/g of fresh weight.

Preliminary Phytochemical Screening, Quantitative Analysis of Alkaloids, and Antioxidant Activity of Crude Plant Extracts from Ephedra intermedia Indigenous to Balochistan

PubMed Central

Jan, Syed Umer; Faridullah, Syed; Sherani, Samiullah; Jahan, Nusrat

2017-01-01

The aim of this study was to evaluate the antioxidant activity, screening the phytogenic chemical compounds, and to assess the alkaloids present in the E. intermedia to prove its uses in Pakistani folk medicines for the treatment of asthma and bronchitis. Antioxidant activity was analyzed by using 2,2-diphenyl-1-picryl-hydrazyl-hydrate assay. Standard methods were used for the identification of cardiac glycosides, phenolic compounds, flavonoids, anthraquinones, and alkaloids. High performance liquid chromatography (HPLC) was used for quantitative purpose of ephedrine alkaloids in E. intermedia. The quantitative separation was confirmed on Shimadzu 10AVP column (Shampack) of internal diameter (id) 3.0 mm and 50 mm in length. The extract of the solute in flow rate of 1 ml/min at the wavelength 210 nm and methanolic extract showed the antioxidant activity and powerful oxygen free radicals scavenging activities and the IC50 for the E. intermedia plant was near to the reference standard ascorbic acid. The HPLC method was useful for the quantitative purpose of ephedrine (E) and pseudoephedrine (PE) used for 45 samples of one species collected from central habitat in three districts (Ziarat, Shairani, and Kalat) of Balochistan. Results showed that average alkaloid substance in E. intermedia was as follows: PE (0.209%, 0.238%, and 0.22%) and E (0.0538%, 0.0666%, and 0.0514%). PMID:28386582

Development and Validation of a Precise, Single HPLC Method for the Determination of Tolperisone Impurities in API and Pharmaceutical Dosage Forms.

PubMed

Raju, Thummala Veera Raghava; Seshadri, Raja Kumar; Arutla, Srinivas; Mohan, Tharlapu Satya Sankarsana Jagan; Rao, Ivaturi Mrutyunjaya; Nittala, Someswara Rao

2013-01-01

A novel, sensitive, stability-indicating HPLC method has been developed for the quantitative estimation of Tolperisone-related impurities in both bulk drugs and pharmaceutical dosage forms. Effective chromatographic separation was achieved on a C18 stationary phase with a simple mobile phase combination delivered in a simple gradient programme, and quantitation was by ultraviolet detection at 254 nm. The mobile phase consisted of a buffer and acetonitrile delivered at a flow rate 1.0 ml/min. The buffer consisted of 0.01 M potassium dihydrogen phosphate with the pH adjusted to 8.0 by using diethylamine. In the developed HPLC method, the resolution between Tolperisone and its four potential impurities was found to be greater than 2.0. Regression analysis showed an R value (correlation coefficient) of greater than 0.999 for the Tolperisone impurities. This method was capable of detecting all four impurities of Tolperisone at a level of 0.19 μg/mL with respect to the test concentration of 1000 μg/mL for a 10 µl injection volume. The tablets were subjected to the stress conditions of hydrolysis, oxidation, photolysis, and thermal degradation. Considerable degradation was found to occur in base hydrolysis, water hydrolysis, and oxidation. The stress samples were assayed against a qualified reference standard and the mass balance was found to be close to 100%. The established method was validated and found to be linear, accurate, precise, specific, robust, and rugged.

Quantitative thin-layer chromatography/mass spectrometry analysis of caffeine using a surface sampling probe electrospray ionization tandem mass spectrometry system.

PubMed

Ford, Michael J; Deibel, Michael A; Tomkins, Bruce A; Van Berkel, Gary J

2005-07-15

Quantitative determination of caffeine on reversed-phase C8 thin-layer chromatography plates using a surface sampling electrospray ionization system with tandem mass spectrometry detection is reported. The thin-layer chromatography/electrospray tandem mass spectrometry method employed a deuterium-labeled caffeine internal standard and selected reaction monitoring detection. Up to nine parallel caffeine bands on a single plate were sampled in a single surface scanning experiment requiring 35 min at a surface scan rate of 44 mum/s. A reversed-phase HPLC/UV caffeine assay was developed in parallel to assess the mass spectrometry method performance. Limits of detection for the HPLC/UV and thin-layer chromatography/electrospray tandem mass spectrometry methods determined from the calibration curve statistics were 0.20 ng injected (0.50 muL) and 1.0 ng spotted on the plate, respectively. Spike recoveries with standards and real samples ranged between 97 and 106% for both methods. The caffeine content of three diet soft drinks (Diet Coke, Diet Cherry Coke, Diet Pepsi) and three diet sport drinks (Diet Turbo Tea, Speed Stack Grape, Speed Stack Fruit Punch) was measured. The HPLC/UV and mass spectrometry determinations were in general agreement, and these values were consistent with the quoted values for two of the three diet colas. In the case of Diet Cherry Coke and the diet sports drinks, the determined caffeine amounts using both methods were consistently higher (by approximately 8% or more) than the literature values.

Quantitative Caffeine Analysis Using a Surface Sampling Probe Electrospray Ionization Tandem Mass Spectrometry System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ford, Michael J; Deibel, Michael A.; Tomkins, Bruce A

Quantitative determination of caffeine on reversed-phase C8 thin-layer chromatography plates using a surface sampling electrospray ionization system with tandem mass spectrometry detection is reported. The thin-layer chromatography/electrospray tandem mass spectrometry method employed a deuterium-labeled caffeine internal standard and selected reaction monitoring detection. Up to nine parallel caffeine bands on a single plate were sampled in a single surface scanning experiment requiring 35 min at a surface scan rate of 44 {mu}m/s. A reversed-phase HPLC/UV caffeine assay was developed in parallel to assess the mass spectrometry method performance. Limits of detection for the HPLC/UV and thin-layer chromatography/electrospray tandem mass spectrometry methodsmore » determined from the calibration curve statistics were 0.20 ng injected (0.50 {mu}L) and 1.0 ng spotted on the plate, respectively. Spike recoveries with standards and real samples ranged between 97 and 106% for both methods. The caffeine content of three diet soft drinks (Diet Coke, Diet Cherry Coke, Diet Pepsi) and three diet sport drinks (Diet Turbo Tea, Speed Stack Grape, Speed Stack Fruit Punch) was measured. The HPLC/UV and mass spectrometry determinations were in general agreement, and these values were consistent with the quoted values for two of the three diet colas. In the case of Diet Cherry Coke and the diet sports drinks, the determined caffeine amounts using both methods were consistently higher (by 8% or more) than the literature values.« less

HPLC-DAD-ESI-MS Analysis of Flavonoids from Leaves of Different Cultivars of Sweet Osmanthus.

PubMed

Wang, Yiguang; Fu, Jianxin; Zhang, Chao; Zhao, Hongbo

2016-09-14

Osmanthus fragrans Lour. has traditionally been a popular ornamental plant in China. In this study, ethanol extracts of the leaves of four cultivar groups of O. fragrans were analyzed by high-performance liquid chromatography coupled with diode array detection (HPLC-DAD) and high-performance liquid chromatography with electrospray ionization and mass spectrometry (HPLC-ESI-MS). The results suggest that variation in flavonoids among O. fragrans cultivars is quantitative, rather than qualitative. Fifteen components were detected and separated, among which, the structures of 11 flavonoids and two coumarins were identified or tentatively identified. According to principal component analysis (PCA) and hierarchical cluster analysis (HCA) based on the abundance of these components (expressed as rutin equivalents), 22 selected cultivars were classified into four clusters. The seven cultivars from Cluster III ('Xiaoye Sugui', 'Boye Jingui', 'Wuyi Dangui', 'Yingye Dangui', 'Danzhuang', 'Foding Zhu', and 'Tianxiang Taige'), which are enriched in rutin and total flavonoids, and 'Sijigui' from Cluster II which contained the highest amounts of kaempferol glycosides and apigenin 7-O-glucoside, could be selected as potential pharmaceutical resources. However, the chemotaxonomy in this paper does not correlate with the distribution of the existing cultivar groups, demonstrating that the distribution of flavonoids in O. fragrans leaves does not provide an effective means of classification for O. fragrans cultivars based on flower color.

[Continual improvement of quantitative analytical method development of Panax notogineng saponins based on quality by design].

PubMed

Dai, Sheng-Yun; Xu, Bing; Shi, Xin-Yuan; Xu, Xiang; Sun, Ying-Qiang; Qiao, Yan-Jiang

2017-03-01

This study is aimed to propose a continual improvement strategy based on quality by design (QbD). An ultra high performance liquid chromatography (UPLC) method was developed to accomplish the method transformation from HPLC to UPLC of Panax notogineng saponins (PNS) and achieve the continual improvement of PNS based on QbD, for example. Plackett-Burman screening design and Box-Behnken optimization design were employed to further understand the relationship between the critical method parameters (CMPs) and critical method attributes (CMAs). And then the Bayesian design space was built. The separation degree of the critical peaks (ginsenoside Rg₁ and ginsenoside Re) was over 2.0 and the analysis time was less than 17 min by a method chosen from the design space with 20% of the initial concentration of the acetonitrile, 10 min of the isocratic time and 6%•min⁻¹ of the gradient slope. At last, the optimum method was validated by accuracy profile. Based on the same analytical target profile (ATP), the comparison of HPLC and UPLC including chromatograph method, CMA identification, CMP-CMA model and system suitability test (SST) indicated that the UPLC method could shorten the analysis time, improve the critical separation and satisfy the requirement of the SST. In all, HPLC method could be replaced by UPLC for the quantity analysis of PNS. Copyright© by the Chinese Pharmaceutical Association.

HPLC determination of caffeine in coffee beverage

NASA Astrophysics Data System (ADS)

Fajara, B. E. P.; Susanti, H.

2017-11-01

Coffee is the second largest beverage which is consumed by people in the world, besides the water. One of the compounds which contained in coffee is caffeine. Caffeine has the pharmacological effect such as stimulating the central nervous system. The purpose of this study is to determine the level of caffeine in coffee beverages with HPLC method. Three branded coffee beverages which include in 3 of Top Brand Index 2016 Phase 2 were used as samples. Qualitative analysis was performed by Parry method, Dragendorff reagent, and comparing the retention time between sample and caffeine standard. Quantitative analysis was done by HPLC method with methanol-water (95:5v/v) as mobile phase and ODS as stationary phasewith flow rate 1 mL/min and UV 272 nm as the detector. The level of caffeine data was statistically analyzed using Anova at 95% confidence level. The Qualitative analysis showed that the three samples contained caffeine. The average of caffeine level in coffee bottles of X, Y, and Z were 138.048 mg/bottle, 109.699 mg/bottle, and 147.669 mg/bottle, respectively. The caffeine content of the three coffee beverage samples are statistically different (p<0.05). The levels of caffeine contained in X, Y, and Z coffee beverage samples were not meet the requirements set by the Indonesian Standard Agency of 50 mg/serving.

Fast and accurate determination of arsenobetaine in fish tissues using accelerated solvent extraction and HPLC-ICP-MS determination.

PubMed

Wahlen, Raimund

2004-04-01

A high-performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) method has been developed for the fast and accurate analysis of arsenobetaine (AsB) in fish samples extracted by accelerated solvent extraction. The combined extraction and analysis approach is validated using certified reference materials for AsB in fish and during a European intercomparison exercise with a blind sample. Up to six species of arsenic (As) can be separated and quantitated in the extracts within a 10-min isocratic elution. The method is optimized so as to minimize time-consuming sample preparation steps and allow for automated extraction and analysis of large sample batches. A comparison of standard addition and external calibration show no significant difference in the results obtained, which indicates that the LC-ICP-MS method is not influenced by severe matrix effects. The extraction procedure can process up to 24 samples in an automated manner, yet the robustness of the developed HPLC-ICP-MS approach is highlighted by the capability to run more than 50 injections per sequence, which equates to a total run-time of more than 12 h. The method can therefore be used to rapidly and accurately assess the proportion of nontoxic AsB in fish samples with high total As content during toxicological screening studies.

Development and validation of an HPLC method for simultaneous determination of trimethoprim and sulfamethoxazole in human plasma.

PubMed

Sayar, Esin; Sahin, Selma; Cevheroglu, Semsettin; Hincal, A Atilla

2010-09-01

The combination of trimethoprim (TMP) and sulfamethoxazole (SMX) is used in the treatment of many common infections such as urinary, respiratory and gastrointestinal tract infections. The aim of this study was to determine TMP and SMX simultaneously in human plasma samples by high performance liquid chromatography (HPLC) using antipyrine as the internal standard. Separation of the compounds was achieved on a reverse-phase C8 column packed with 5 microm dimethyl octadecylsilyl bonded amorphous silica (4.6 mm x 250 mm) column using a mobile phase consisted of potassium hydrogen phosphate, acetonitrile, methanol and water adjusted to pH 6.2. The mobile phase was delivered at a flow rate of 1 mL min- and the effluent was monitored using Max plot technique at 25 derees C. Retention times were 5 min for TMP, 7 min for antipyrine and 9 min for SMX. Quantitation limits were 10 ng mL(-1) for TMP and 50 ng mL(-1) for SMX. Our findings indicated that the developed HPLC method was precise, accurate, specific and sensitive for simultaneous determination of TMP and SMX. Proposed HPLC method was successfully applied for the analysis of TMP and SMX in human plasma after oral administration of a co-trimoxazole tablet to human volunteers.

Detection of Free Polyamines in Plants Subjected to Abiotic Stresses by High-Performance Liquid Chromatography (HPLC).

PubMed

Gong, Xiaoqing; Liu, Ji-Hong

2017-01-01

High-performance liquid chromatography (HPLC) is a sensitive, rapid, and accurate technique to detect and characterize various metabolites from plants. The metabolites are extracted with different solvents and eluted with appropriate mobile phases in a designed HPLC program. Polyamines are known to accumulate under abiotic stress conditions in various plant species and thought to provide protection against oxidative stress by scavenging reactive oxygen species. Here, we describe a common method to detect the free polyamines in plant tissues both qualitatively and quantitatively.

Development and optimization of SPE-HPLC-UV/ELSD for simultaneous determination of nine bioactive components in Shenqi Fuzheng Injection based on Quality by Design principles.

PubMed

Wang, Lu; Qu, Haibin

2016-03-01

A method combining solid phase extraction, high performance liquid chromatography, and ultraviolet/evaporative light scattering detection (SPE-HPLC-UV/ELSD) was developed according to Quality by Design (QbD) principles and used to assay nine bioactive compounds within a botanical drug, Shenqi Fuzheng Injection. Risk assessment and a Plackett-Burman design were utilized to evaluate the impact of 11 factors on the resolutions and signal-to-noise of chromatographic peaks. Multiple regression and Pareto ranking analysis indicated that the sorbent mass, sample volume, flow rate, column temperature, evaporator temperature, and gas flow rate were statistically significant (p < 0.05) in this procedure. Furthermore, a Box-Behnken design combined with response surface analysis was employed to study the relationships between the quality of SPE-HPLC-UV/ELSD analysis and four significant factors, i.e., flow rate, column temperature, evaporator temperature, and gas flow rate. An analytical design space of SPE-HPLC-UV/ELSD was then constructed by calculated Monte Carlo probability. In the presented approach, the operating parameters of sample preparation, chromatographic separation, and compound detection were investigated simultaneously. Eight terms of method validation, i.e., system-suitability tests, method robustness/ruggedness, sensitivity, precision, repeatability, linearity, accuracy, and stability, were accomplished at a selected working point. These results revealed that the QbD principles were suitable in the development of analytical procedures for samples in complex matrices. Meanwhile, the analytical quality and method robustness were validated by the analytical design space. The presented strategy provides a tutorial on the development of a robust QbD-compliant quantitative method for samples in complex matrices.

Quantitative study of fruit flavonoids in citrus hybrids of King (C. nobilis) and Mukaku Kishu (C. kinokuni).

PubMed

Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Nonomura-Nakano, M; Nesumi, H; Yoshida, T; Sugiura, M; Yano, M

2001-08-01

Twenty-four Citrus hybrids of King (C. nobilis) and Mukaku Kishu (C. kinokuni) were examined for their flavonoid profiles of the edible part by reversed-phase HPLC analysis. Two hybrids (G-155 and G-156) contained higher amounts of natsudaidain than their parents, whereas the remainder of the hybrids had a character intermediate between those of King and Mukaku Kishu on the basis of polymethoxylated flavone composition. Principal component analysis revealed the distribution of the hybrids by quantifying 23 flavonoid contents.

A novel approach for the quantitation of carbohydrates in mash, wort, and beer with RP-HPLC using 1-naphthylamine for precolumn derivatization.

PubMed

Rakete, Stefan; Glomb, Marcus A

2013-04-24

A novel universal method for the determination of reducing mono-, di-, and oligosaccharides in complex matrices on RP-HPLC using 1-naphthylamine for precolumn derivatization with sodium cyanoborhydride was established to study changes in the carbohydrate profile during beer brewing. Fluorescence and mass spectrometric detection enabled very sensitive analyses of beer-relevant carbohydrates. Mass spectrometry additionally allowed the identification of the molecular weight and thereby the degree of polymerization of unknown carbohydrates. Thus, carbohydrates with up to 16 glucose units were detected. Comparison demonstrated that the novel method was superior to fluorophore-assisted carbohydrate electrophoresis (FACE). The results proved the HPLC method clearly to be more powerful in regard to sensitivity and resolution. Analogous to FACE, this method was designated fluorophore-assisted carbohydrate HPLC (FAC-HPLC).

Detection and quantification of new psychoactive substances (NPSs) within the evolved "legal high" product, NRG-2, using high performance liquid chromatography-amperometric detection (HPLC-AD).

PubMed

Zuway, Khaled Y; Smith, Jamie P; Foster, Christopher W; Kapur, Nikil; Banks, Craig E; Sutcliffe, Oliver B

2015-09-21

The global increase in the production and abuse of cathinone-derived New Psychoactive Substances (NPSs) has developed the requirement for rapid, selective and sensitive protocols for their separation and detection. Electrochemical sensing of these compounds has been demonstrated to be an effective method for the in-field detection of these substances, either in their pure form or in the presence of common adulterants, however, the technique is limited in its ability to discriminate between structurally related cathinone-derivatives (for example: (±)-4′-methylmethcathinone (4-MMC, 2a) and (±)-4′-methyl-N-ethylmethcathinone (4-MEC, 2b) when they are both present in a mixture. In this paper we demonstrate, for the first time, the combination of HPLC-UV with amperometric detection (HPLC-AD) for the qualitative and quantitative analysis of 4-MMC and 4-MEC using either a commercially available impinging jet (LC-FC-A) or custom-made iCell channel (LC-FC-B) flow-cell system incorporating embedded graphite screen-printed macroelectrodes. The protocol offers a cost-effective, reproducible and reliable sensor platform for the simultaneous HPLC-UV and amperometric detection of the target analytes. The two systems have similar limits of detection, in terms of amperometric detection [LC-FC-A: 14.66 μg mL(-1) (2a) and 9.35 μg mL(-1) (2b); LC-FC-B: 57.92 μg mL(-1) (2a) and 26.91 μg mL(-1) (2b)], to the previously reported oxidative electrochemical protocol [39.8 μg mL(-1) (2a) and 84.2 μg mL(-1) (2b)], for two synthetic cathinones, prevalent on the recreational drugs market. Though not as sensitive as standard HPLC-UV detection, both flow cells show a good agreement, between the quantitative electroanalytical data, thereby making them suitable for the detection and quantification of 4-MMC and 4-MEC, either in their pure form or within complex mixtures. Additionally, the simultaneous HPLC-UV and amperometric detection protocol detailed herein shows a marked improvement and advantage over previously reported electroanalytical methods, which were either unable to selectively discriminate between structurally related synthetic cathinones (e.g. 4-MMC and 4-MEC) or utilised harmful and restrictive materials in their design.

Optimizing high-performance liquid chromatography method for quantification of glucosamine using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate derivatization in rat plasma: application to a pharmacokinetic study.

PubMed

Wang, Xianhuo; Chen, Xiang; Chen, Lijuan; Wang, Biqin; Peng, Cheng; He, Chunmei; Tang, Minghai; Zhang, Fan; Hu, Jia; Li, Rui; Zhao, Xia; Wei, Yuquan

2008-11-01

A sensitive and reliable HPLC method with fluorescence detection based on the precolumn derivatization of glucosamine with 6-aminoquinolyl-N-hydroxylsuccinimidyl carbamate (AQC) was established for the quantitative determination of glucosamine in rat plasma. The plasma protein was precipitated by acetonitrile, followed by vortex mixing and centrifugation. The supernatant was divided into the organic layer and aqueous layer by adding sodium chloride, and then the aqueous layer was derivatized with AQC in 0.2 M borate buffer of pH 8.8 before the HPLC analysis. An amino acid analysis column (3.9 x 150 mm, 4 microm) was applied, with 140 mM sodium acetate buffer (pH = 5.25) and acetonitrile as mobile phase at a flow rate of 1 mL/min. A linear correlation coefficient of 0.9987 was calculated within the range of 0.1-30 microg/mL of the standard curve for glucosamine. The limit of detection was 30 ng/mL. The intra- and inter-day precisions (as RSD) were less than 7.38 and 12.72%, respectively. The intra- and inter-day accuracy ranged from 91.8 to 110.0%. Extraction recoveries of glucosamine in plasma were more than 90%. The validated method was successfully applied for the quantitative determination of glucosamine in rat plasma and evaluation for pharmacokinetic study of glucosamine. It was also possible to be applied for the quantitative determination of other compounds containing amino group in biological samples.

Applications of HPLC/MS in the analysis of traditional Chinese medicines

PubMed Central

Li, Miao; Hou, Xiao-Fang; Zhang, Jie; Wang, Si-Cen; Fu, Qiang; He, Lang-Chong

2012-01-01

In China, traditional Chinese medicines (TCMs) have been used in clinical applications for thousands of years. The successful hyphenation of high-Performance liquid chromatography (HPLC) and mass spectrometry (MS) has been applied widely in TCMs and biological samples analysis. Undoubtedly, HPLC/MS technique has facilitated the understanding of the treatment mechanism of TCMs. We reviewed more than 350 published papers within the last 5 years on HPLC/MS in the analysis of TCMs. The present review focused on the applications of HPLC/MS in the component analysis, metabolites analysis, and pharmacokinetics of TCMs etc. 50% of the literature is related to the component analysis of TCMs, which show that this field is the most populär type of research. In the metabolites analysis, HPLC coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry has been demonstrated to be the powerful tool for the characterization of structural features and fragmentation behavior patterns. This paper presented a brief overview of the applications of HPLC/MS in the analysis of TCMs. HPLC/MS in the fingerprint analysis is reviewed elsewhere. PMID:29403684

HPLC and LC-MS/MS methods for determination of sodium benzoate and potassium sorbate in food and beverages: performances of local accredited laboratories via proficiency tests in Turkey.

PubMed

Gören, Ahmet C; Bilsel, Gökhan; Şimşek, Adnan; Bilsel, Mine; Akçadağ, Fatma; Topal, Kevser; Ozgen, Hasan

2015-05-15

High Performance Liquid Chromatography LC-UV and LC-MS/MS methods were developed and validated for quantitative analyses of sodium benzoate and potassium sorbate in foods and beverages. HPLC-UV and LC-MS/MS methods were compared for quantitative analyses of sodium benzoate and potassium sorbate in a representative ketchup sample. Optimisation of the methods enabled the chromatographic separation of the analytes in less than 4 min. A correlation coefficient of 0.999 was achieved over the measured calibration range for both compounds and methods (HPLC and LC-MS/MS). The uncertainty values of sodium benzoate and potassium sorbate were found as 0.199 and 0.150 mg/L by HPLC and 0.072 and 0.044 mg/L by LC-MS/MS, respectively. Proficiency testing performance of Turkish accredited laboratories between the years 2005 and 2013 was evaluated and reported herein. The aim of the proficiency testing scheme was to evaluate the performance of the laboratories, analysing benzoate and sorbate in tomato ketchup. Copyright © 2014 Elsevier Ltd. All rights reserved.

ANTIPROTOZOAL ACTIVITY OF EXTRACTS OF ELAEODENDRON TRICHOTOMUM (CELASTRACEAE).

PubMed

Roca-Mézquita, Carolina; Graniel-Sabido, Manlio; Moo-Puc, Rosa E; Leon-Déniz, Lorena V; Gamboa-León, Rubí; Arjona-Ruiz, Carely; Tun-Garrido, Juan; Mirón-López, Gumersindo; Mena-Rejón, Gonzalo J

2016-01-01

Chagas disease, amebiasis, giardiasis and trichomoniasis represent a serious health problem in Latin America. The drugs employed to treat these illnesses produce important side effects and resistant strains have appeared. The present study was aimed to evaluate the antiprotozoal activity of leaves, stem bark and root bark of Elaeodendron trichotomum , a celastraceus, that is used in Mexico as an anti-infective in febrile-type diseases. Dichloromethane and methanol extracts of leaves, bark and roots of Elaeodendron trichotomum were tested against Entamoeba histolytica , Giardia lamblia , Trichomonas vaginalis , and Trypanosoma cruzi . A quantitative HPLC analysis of pristimerin and tingenone was performed. The dichloromethane extract of roots was active against E. histolytica , G. lamblia , T. vaginalis , and T. cruzi , at IC50's of 0.80, 0.44, 0.46, and 2.68 μg/mL, respectively. The HPLC analysis revealed the presence of tingenone (3.84%) and pristimerin (0.14%). The dichloromethane extract of the roots bark showed significant activity against all screened protozoa.

ANTIPROTOZOAL ACTIVITY OF EXTRACTS OF ELAEODENDRON TRICHOTOMUM (CELASTRACEAE)

PubMed Central

Roca-Mézquita, Carolina; Graniel-Sabido, Manlio; Moo-Puc, Rosa E.; Leon-Déniz, Lorena V.; Gamboa-León, Rubí; Arjona-Ruiz, Carely; Tun-Garrido, Juan; Mirón-López, Gumersindo; Mena-Rejón, Gonzalo J.

2016-01-01

Background: Chagas disease, amebiasis, giardiasis and trichomoniasis represent a serious health problem in Latin America. The drugs employed to treat these illnesses produce important side effects and resistant strains have appeared. The present study was aimed to evaluate the antiprotozoal activity of leaves, stem bark and root bark of Elaeodendron trichotomum, a celastraceus, that is used in Mexico as an anti-infective in febrile-type diseases. Materials and methods: Dichloromethane and methanol extracts of leaves, bark and roots of Elaeodendron trichotomum were tested against Entamoeba histolytica, Giardia lamblia, Trichomonas vaginalis, and Trypanosoma cruzi. A quantitative HPLC analysis of pristimerin and tingenone was performed. Results: The dichloromethane extract of roots was active against E. histolytica, G. lamblia, T. vaginalis, and T. cruzi, at IC50’s of 0.80, 0.44, 0.46, and 2.68 μg/mL, respectively. The HPLC analysis revealed the presence of tingenone (3.84%) and pristimerin (0.14%). Conclusions: The dichloromethane extract of the roots bark showed significant activity against all screened protozoa. PMID:28852732

HPLC-PDA Combined with Chemometrics for Quantitation of Active Components and Quality Assessment of Raw and Processed Fruits of Xanthium strumarium L.

PubMed

Jiang, Hai; Yang, Liu; Xing, Xudong; Yan, Meiling; Guo, Xinyue; Yang, Bingyou; Wang, Qiuhong; Kuang, Haixue

2018-01-25

As a valuable herbal medicine, the fruits of Xanthium strumarium L. (Xanthii Fructus) have been widely used in raw and processed forms to achieve different therapeutic effects in practice. In this study, a comprehensive strategy was proposed for evaluating the active components in 30 batches of raw and processed Xanthii Fructus (RXF and PXF) samples, based on high-performance liquid chromatography coupled with photodiode array detection (HPLC-PDA). Twelve common peaks were detected and eight compounds of caffeoylquinic acids were simultaneously quantified in RXF and PXF. All the analytes were detected with satisfactory linearity (R² > 0.9991) over wide concentration ranges. Simultaneously, the chemically latent information was revealed by hierarchical cluster analysis (HCA) and principal component analysis (PCA). The results suggest that there were significant differences between RXF and PXF from different regions in terms of the content of eight caffeoylquinic acids. Potential chemical markers for XF were found during processing by chemometrics.

Qualitative and quantitative analyses of Epimedium wushanense by high-performance liquid chromatography coupled with diode array detection and electrospray ionization tandem mass spectrometry.

PubMed

Li, Hui-fang; Guan, Xiang-yu; Ye, Min; Xiang, Cheng; Lin, Chang-hu; Sun, Chao; Guo, De-an

2011-06-01

A new HPLC-DAD-ESI-MS(n) method was developed for rapid separation, characterization and quantitation of flavonoids in Epimedium wushanense, a popular Chinese herbal medicine. For qualitative identification, a total of 37 compounds were characterized from the underground and aerial parts of E. wushanense. Among them, 28 compounds were prenylated flavonoids, and 23 were confirmed by comparing with reference standards. For quantitative analysis, 12 major flavonoids including kaempferol glycosides, desmethylicaritin glycosides, and icaritin glycosides were simultaneously determined by HPLC/UV. Samples were separated on a Waters Symmetry C(18) column at 35 °C eluted with a gradient three-component mobile phase of acetonitrile, methanol, and water containing 0.03% v/v formic acid. All the flavonoids showed good linearity (r(2) ≥0.9997). The recoveries varied from 92.6 to 106.1% at three concentration levels. This method was applied to the determination of 20 samples of different geographical sources, harvesting time, and plant parts. Contents of the predominant flavonoid, epimedin C, ranged from 1.4 to 5.1% in aerial parts and 1.0 to 2.8% in underground parts. The methods established in this paper were simple and reliable and could be used for the quality control of E. wushanense. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Identification and Quantitation of Flavanols and Proanthocyanidins in Foods: How Good are the Datas?

PubMed Central

Kelm, Mark A.; Hammerstone, John F.; Schmitz, Harold H.

2005-01-01

Evidence suggesting that dietary polyphenols, flavanols, and proanthocyanidins in particular offer significant cardiovascular health benefits is rapidly increasing. Accordingly, reliable and accurate methods are needed to provide qualitative and quantitative food composition data necessary for high quality epidemiological and clinical research. Measurements for flavonoids and proanthocyanidins have employed a range of analytical techniques, with various colorimetric assays still being popular for estimating total polyphenolic content in foods and other biological samples despite advances made with more sophisticated analyses. More crudely, estimations of polyphenol content as well as antioxidant activity are also reported with values relating to radical scavenging activity. High-performance liquid chromatography (HPLC) is the method of choice for quantitative analysis of individual polyphenols such as flavanols and proanthocyanidins. Qualitative information regarding proanthocyanidin structure has been determined by chemical methods such as thiolysis and by HPLC-mass spectrometry (MS) techniques at present. The lack of appropriate standards is the single most important factor that limits the aforementioned analyses. However, with ever expanding research in the arena of flavanols, proanthocyanidins, and health and the importance of their future inclusion in food composition databases, the need for standards becomes more critical. At present, sufficiently well-characterized standard material is available for selective flavanols and proanthocyanidins, and construction of at least a limited food composition database is feasible. PMID:15712597

Identification, quantitation, and method validation for flavan-3-ols in fermented ready-to-drink teas from the Italian market using HPLC-UV/DAD and LC-MS/MS.

PubMed

Cordero, Chiara; Canale, Francesca; Del Rio, Daniele; Bicchi, Carlo

2009-11-01

The present study is focused on flavan-3-ols characterizing the antioxidant properties of fermented tea (Camellia sinensis). These bioactive compounds, object of nutritional claims in commercial products, should be quantified with rigorous analytical procedures whose accuracy and precision have been stated with a certain level of confidence. An HPLC-UV/DAD method, able to detect and quantify flavan-3-ols in infusions and ready-to-drink teas, has been developed for routine analysis and validated by characterizing several performance parameters. The accuracy assessment has been run through a series of LC-MS/MS analyses. Epigallocatechin, (+)-catechin, (-)-epigallocatechingallate, (-)-epicatechin, (-)-gallocatechingallate, (-)-epicatechingallate, and (-)-catechingallate were chosen as markers of the polyphenolic fraction. Quantitative results showed that samples obtained from tea leaves infusion were richer in polyphenolic antioxidants than those obtained through other industrial processes. The influence of shelf-life and packaging material on the flavan-3-ols content was also considered; markers decreased, with an exponential trend, as a function of time within the shelf life while packaging materials demonstrated to influence differently the flavan-3-ol fraction composition over time. The method presented here provides quantitative results with a certain level of confidence and is suitable for a routine quality control of iced teas whose antioxidant properties are object of nutritional claim.

Development and validation of stability indicating method for the quantitative determination of venlafaxine hydrochloride in extended release formulation using high performance liquid chromatography

PubMed Central

Kaur, Jaspreet; Srinivasan, K. K.; Joseph, Alex; Gupta, Abhishek; Singh, Yogendra; Srinivas, Kona S.; Jain, Garima

2010-01-01

Objective: Venlafaxine,hydrochloride is a structurally novel phenethyl bicyclic antidepressant, and is usually categorized as a serotonin–norepinephrine reuptake inhibitor (SNRI) but it has been referred to as a serotonin–norepinephrine–dopamine reuptake inhibitor. It inhibits the reuptake of dopamine. Venlafaxine HCL is widely prescribed in the form of sustained release formulations. In the current article we are reporting the development and validation of a fast and simple stability indicating, isocratic high performance liquid chromatographic (HPLC) method for the determination of venlafaxine hydrochloride in sustained release formulations. Materials and Methods: The quantitative determination of venlafaxine hydrochloride was performed on a Kromasil C18 analytical column (250 × 4.6 mm i.d., 5 μm particle size) with 0.01 M phosphate buffer (pH 4.5): methanol (40: 60) as a mobile phase, at a flow rate of 1.0 ml/min. For HPLC methods, UV detection was made at 225 nm. Results: During method validation, parameters such as precision, linearity, accuracy, stability, limit of quantification and detection and specificity were evaluated, which remained within acceptable limits. Conclusions: The method has been successfully applied for the quantification and dissolution profiling of Venlafaxine HCL in sustained release formulation. The method presents a simple and reliable solution for the routine quantitative analysis of Venlafaxine HCL. PMID:21814426

[Simultaneous determination of 4 diterpenoids in Rabdosia japonica var.glaucocalyx by HPLC-ESI-MS/MS and cluster analysis].

PubMed

Tian, Ting-Ting; Ma, Ying-Hua; Xie, Wei-Wei; Jin, Yi-Ran; Xu, Hui-Jun; Zhang, Lan-Tong; Du, Ying-Feng

2016-01-01

A quick HPLC-ESI-MS/MS method was established for simultaneous determination of four major diterpenoids in Rabdosia japonica var.glaucocalyx, including glaucocalyxin A, oridonin, hebeirubesensin and enmenol. Analysis was performed on an Agilent ZORBAX SB-C18(4.6 mm×250 mm, 5 μm ) column eluted in a gradient program with methanol and water. The flow rate was 0.8 mL•min⁻¹. Multiple reaction monitoring (MRM) scanning mode was performed in negative ion switching mode to apply for the quantitative determination. The calibration curves for the above four compounds were linear in corresponding injection amount. The average recoveries of the compounds ranged from 92.40% to 105.9%, with RSDs of 1.7%-6.5%. The method is simple, rapid, accurate with good repeatability, which can provide a reference for overcalling evaluation the quality of R. japonica var.glaucocalyx. The result of cluster analysis- showed that the quality of R. japonica glaucocalyx var. greatly varied between areas and parts. Copyright© by the Chinese Pharmaceutical Association.

Chemical analysis of Panax quinquefolius (North American ginseng): A review.

PubMed

Wang, Yaping; Choi, Hyung-Kyoon; Brinckmann, Josef A; Jiang, Xue; Huang, Linfang

2015-12-24

Panax quinquefolius (PQ) is one of the best-selling natural health products due to its proposed beneficial anti-aging, anti-cancer, anti-stress, anti-fatigue, and anxiolytic effects. In recent years, the quality of PQ has received considerable attention. Sensitive and accurate methods for qualitative and quantitative analyses of chemical constituents are necessary for the comprehensive quality control to ensure the safety and efficacy of PQ. This article reviews recent progress in the chemical analysis of PQ and its preparations. Numerous analytical techniques, including spectroscopy, thin-layer chromatography (TLC), gas chromatography (GC), high-performance liquid chromatography (HPLC), liquid chromatography/mass spectrometry (LC/MS), high-speed centrifugal partition chromatography (HSCPC), high-performance counter-current chromatography (HPCCC), nuclear magnetic resonance spectroscopy (NMR), and immunoassay, are described. Among these techniques, HPLC coupled with mass spectrometry (MS) is the most promising method for quality control. The challenges encountered in the chemical analysis of PQ are also briefly discussed, and the remaining questions regarding the quality control of PQ that require further investigation are highlighted. Copyright © 2015 Elsevier B.V. All rights reserved.

Development of an Analytic Method for Sulfur Compounds in Aged Garlic Extract with the Use of a Postcolumn High Performance Liquid Chromatography Method with Sulfur-Specific Detection.

PubMed

Matsutomo, Toshiaki; Kodera, Yukihiro

2016-02-01

Garlic and its processed preparations contain numerous sulfur compounds that are difficult to analyze in a single run using HPLC. The aim of this study was to develop a rapid and convenient sulfur-specific HPLC method to analyze sulfur compounds in aged garlic extract (AGE). We modified a conventional postcolumn HPLC method by employing a hexaiodoplatinate reagent. Identification and structural analysis of sulfur compounds were conducted by LC-mass spectrometry (LC-MS) and nuclear magnetic resonance. The production mechanisms of cis-S-1-propenylcysteine (cis-S1PC) and S-allylmercaptocysteine (SAMC) were examined by model reactions. Our method has the following advantages: less interference from nonsulfur compounds, high sensitivity, good correlation coefficients (r > 0.98), and high resolution that can separate >20 sulfur compounds, including several isomers, in garlic preparations in a single run. This method was adapted for LC-MS analysis. We identified cis-S1PC and γ-glutamyl-S-allyl-mercaptocysteine in AGE. The results of model reactions suggest that cis-S1PC is produced from trans-S1PC through an isomerization reaction and that SAMC is produced by a reaction involving S-allylcysteine/S1PC and diallyldisulfide during the aging period. We developed a rapid postcolumn HPLC method for both qualitative and quantitative analyses of sulfur compounds, and this method helped elucidate a potential mechanism of cis-S1PC and SAMC action in AGE. © 2016 American Society for Nutrition.

Intelligent peak deconvolution through in-depth study of the data matrix from liquid chromatography coupled with a photo-diode array detector applied to pharmaceutical analysis.

PubMed

Arase, Shuntaro; Horie, Kanta; Kato, Takashi; Noda, Akira; Mito, Yasuhiro; Takahashi, Masatoshi; Yanagisawa, Toshinobu

2016-10-21

Multivariate curve resolution-alternating least squares (MCR-ALS) method was investigated for its potential to accelerate pharmaceutical research and development. The fast and efficient separation of complex mixtures consisting of multiple components, including impurities as well as major drug substances, remains a challenging application for liquid chromatography in the field of pharmaceutical analysis. In this paper we suggest an integrated analysis algorithm functioning on a matrix of data generated from HPLC coupled with photo-diode array detector (HPLC-PDA) and consisting of the mathematical program for the developed multivariate curve resolution method using an expectation maximization (EM) algorithm with a bidirectional exponentially modified Gaussian (BEMG) model function as a constraint for chromatograms and numerous PDA spectra aligned with time axis. The algorithm provided less than ±1.0% error between true and separated peak area values at resolution (R s ) of 0.6 using simulation data for a three-component mixture with an elution order of a/b/c with similarity (a/b)=0.8410, (b/c)=0.9123 and (a/c)=0.9809 of spectra at peak apex. This software concept provides fast and robust separation analysis even when method development efforts fail to achieve complete separation of the target peaks. Additionally, this approach is potentially applicable to peak deconvolution, allowing quantitative analysis of co-eluted compounds having exactly the same molecular weight. This is complementary to the use of LC-MS to perform quantitative analysis on co-eluted compounds using selected ions to differentiate the proportion of response attributable to each compound. Copyright © 2016 Elsevier B.V. All rights reserved.

Qualitative and quantitative analysis of monomers in polyesters for food contact materials.

PubMed

Brenz, Fabrian; Linke, Susanne; Simat, Thomas

2017-02-01

Polyesters (PESs) are gaining more importance on the food contact material (FCM) market and the variety of properties and applications is expected to be wide. In order to acquire the desired properties manufacturers can combine several FCM-approved polyvalent carboxylic acids (PCAs) and polyols as monomers. However, information about the qualitative and quantitative composition of FCM articles is often limited. The method presented here describes the analysis of PESs with the identification and quantification of 25 PES monomers (10 PCA, 15 polyols) by HPLC with diode array detection (HPLC-DAD) and GC-MS after alkaline hydrolysis. Accurate identification and quantification were demonstrated by the analysis of seven different FCM articles made of PESs. The results explained between 97.2% and 103.4% w/w of the polymer composition whilst showing equal molar amounts of PCA and polyols. Quantification proved to be precise and sensitive with coefficients of variation (CVs) below 6.0% for PES samples with monomer concentrations typically ranging from 0.02% to 75% w/w. The analysis of 15 PES samples for the FCM market revealed the presence of five different PCAs and 11 different polyols (main monomers, co-monomers, non-intentionally added substances (NIAS)) showing the wide variety of monomers in modern PESs. The presented method provides a useful tool for commercial, state and research laboratories as well as for producers and distributors facing the task of FCM risk assessment. It can be applied for the identification and quantification of migrating monomers and the prediction of oligomer compositions from the identified monomers, respectively.

Quantitative analysis of three chiral pesticide enantiomers by high-performance column liquid chromatography.

PubMed

Wang, Peng; Liu, Donghui; Gu, Xu; Jiang, Shuren; Zhou, Zhiqiang

2008-01-01

Methods for the enantiomeric quantitative determination of 3 chiral pesticides, paclobutrazol, myclobutanil, and uniconazole, and their residues in soil and water are reported. An effective chiral high-performance liquid chromatographic (HPLC)-UV method using an amylose-tris(3,5-dimethylphenylcarbamate; AD) column was developed for resolving the enantiomers and quantitative determination. The enantiomers were identified by a circular dichroism detector. Validation involved complete resolution of each of the 2 enantiomers, plus determination of linearity, precision, and limit of detection (LOD). The pesticide enantiomers were isolated by solvent extraction from soil and C18 solid-phase extraction from water. The 2 enantiomers of the 3 pesticides could be completely separated on the AD column using n-hexane isopropanol mobile phase. The linearity and precision results indicated that the method was reliable for the quantitative analysis of the enantiomers. LODs were 0.025, 0.05, and 0.05 mg/kg for each enantiomer of paclobutrazol, myclobutanil, and uniconazole, respectively. Recovery and precision data showed that the pretreatment procedures were satisfactory for enantiomer extraction and cleanup. This method can be used for optical purity determination of technical material and analysis of environmental residues.

Liquid chromatographic separation of terpenoid pigments in foods and food products.

PubMed

Cserháti, T; Forgács, E

2001-11-30

The newest achievements in the use of various liquid chromatographic techniques such as adsorption and reversed-phase thin-layer chromatography and HPLC employed for the separation and quantitative determination of terpenoid-based color substances in foods and food products are reviewed. The techniques applied for the analysis of individual pigments and pigments classes are surveyed and critically evaluated. Future trends in the separation and identification of pigments in foods and food products are delineated.

Surface Passivation of InAs(001) With Thioacetamide

DTIC Science & Technology

2005-01-01

Fitting and quantitative analysis of the In 3d data are described in detail elsewhere.9 Oxidation of As requires breaching the top two layers of the S...ACS or HPLC grade used with- out additional purificationd. The average S coverage after these exposures was reduced by ᝿% compared to as- passivated...embedding one-half of an InAs sample in freshly cast polydimethylsiloxane sPDMSd followed by hardening the PDMS overnight at room tem- perature. After 30

Quantitative Correlation of in Vivo Properties with in Vitro Assay Results: The in Vitro Binding of a Biotin–DNA Analogue Modifier with Streptavidin Predicts the in Vivo Avidin-Induced Clearability of the Analogue-Modified Antibody

PubMed Central

Dou, Shuping; Virostko, John; Greiner, Dale L.; Powers, Alvin C.; Liu, Guozheng

2016-01-01

Quantitative prediction of in vivo behavior using an in vitro assay would dramatically accelerate pharmaceutical development. However, studies quantitatively correlating in vivo properties with in vitro assay results are rare because of the difficulty in quantitatively understanding the in vivo behavior of an agent. We now demonstrate such a correlation as a case study based on our quantitative understanding of the in vivo chemistry. In an ongoing pretargeting project, we designed a trifunctional antibody (Ab) that concomitantly carried a biotin and a DNA analogue (hereafter termed MORF). The biotin and the MORF were fused into one structure prior to conjugation to the Ab for the concomitant attachment. Because it was known that avidin-bound Ab molecules leave the circulation rapidly, this design would theoretically allow complete clearance by avidin. The clearability of the trifunctional Ab was determined by calculating the blood MORF concentration ratio of avidin-treated Ab to non-avidin-treated Ab using mice injected with these compounds. In theory, any compromised clearability should be due to the presence of impurities. In vitro, we measured the biotinylated percentage of the Ab-reacting (MORF-biotin)⊃-NH2 modifier, by addition of streptavidin to the radiolabeled (MORF-biotin)⊃-NH2 samples and subsequent high-performance liquid chromatography (HPLC) analysis. On the basis of our previous quantitative understanding, we predicted that the clearability of the Ab would be equal to the biotinylation percentage measured via HPLC. We validated this prediction within a 3% difference. In addition to the high avidin-induced clearability of the trifunctional Ab (up to ~95%) achieved by the design, we were able to predict the required quality of the (MORF-biotin)⊃-NH2 modifier for any given in vivo clearability. This approach may greatly reduce the steps and time currently required in pharmaceutical development in the process of synthesis, chemical analysis, in vitro cell study, and in vivo validation. PMID:26103429

Quantitative and Qualitative Analysis of Flavonoids and Phenolic Acids in Snow Chrysanthemum (Coreopsis tinctoria Nutt.) by HPLC-DAD and UPLC-ESI-QTOF-MS.

PubMed

Yang, Yinjun; Sun, Xinguang; Liu, Jinjun; Kang, Liping; Chen, Sibao; Ma, Baiping; Guo, Baolin

2016-09-30

A simple, accurate and reliable high performance liquid chromatography coupled with photodiode array detection (HPLC-DAD) method was developed and then successfully applied for simultaneous quantitative analysis of eight compounds, including chlorogenic acid ( 1 ), ( R / S )-flavanomarein ( 2 ), butin-7- O -β-d-glucopyranoside ( 3 ), isookanin ( 4 ), taxifolin ( 5 ), 5,7,3',5'-tetrahydroxyflavanone-7- O -β-d-glucopyranoside ( 6 ), marein ( 7 ) and okanin ( 8 ), in 23 batches of snow chrysanthemum of different seed provenance and from various habitats. The results showed total contents of the eight compounds in the samples with seed provenance from Keliyang (Xinjiang, China), are higher than in samples from the other five provenances by 52.47%, 15.53%, 19.78%, 21.17% and 5.06%, respectively, which demonstrated that provenance has a great influence on the constituents in snow chrysanthemum. Meanwhile, an ultra performance liquid chromatography coupled with electrospray ionization and quadrupole time-of-flight-mass spectrometry (UPLC-ESI-QTOF-MS) was also employed to rapidly separate and identify flavonoids and phenolic acids in snow chrysanthemum from Keliyang. As a result, a total of 30 constituents, including 26 flavonoids and four phenolic acids, were identified or tentatively identified based on the exact mass information, the fragmentation characteristics, and retention times of eight reference standards. This work may provide an efficient approach to comprehensively evaluate the quality of snow chrysanthemum.

A high-pressure liquid chromatographic method for the determination of N-acetyl-p-aminophenol (acetaminophen) in serum or plasma using a direct injection technique.

PubMed

Manno, B R; Manno, J E; Dempsey, C A; Wood, M A

1981-01-01

N-Acetyl-p-aminophenol (acetaminophen) is becoming more prevalent as an intoxicant in accidental or intentional overdose, therefore, a direct injection ultra-micro high-pressure liquid chromatographic (HPLC) method has been developed for its quantitation. The HPLC analysis was performed using a Model 110 Solvent Metering Pump equipped with a Model 110-19 Pressure Filter (Altex Scientific, Berkeley, CA), a Model 7120 Rheodyne Injector (Rheodyne, Berkeley, CA) or a Model U6K Injector (Waters Associates, Milford, MA) a Model 440 Absorbance Detector (Water's Associates), and a Model 3380A Recorder Integrator (Hewlett Packard, Avondale, PA). A commercially prepared muBonapak C18 Column (Water's Associates) was used. Acetaminophen was eluted with a mixture of 0.01 mol/L aqueous sodium acetate, pH 4.0: acetonitrile (93:7) and the absorbance detector was operated wih a 254 nm filter. The method, which requires only 2 microL of serum or plasma for analysis, offers several distinct advantages to the analyst. No pre- or post-column extraction or other manipulation of the specimen is required to obtain a quantitative result. Rapid processing of the specimen is possible because both acetaminophen and the internal standard are eluted in less than 10 minutes. The small sample (2 microL) is ideal for use with pediatric patients.

Determination of 13-cis-retinoic acid and its major metabolite, 4-oxo-13-cis-retinoic acid, in human blood by reversed-phase high-performance liquid chromatography.

PubMed

Vane, F M; Stoltenborg, J K; Buggé, C J

1982-02-12

A high-performance liquid chromatography (HPLC) method for the quantitation of 13-cis-retinoic acid (13-cis-RA) and its major metabolite, 4-oxo-13-cis-RA, in human blood has been developed. The method includes extraction of 1 ml of blood with diethyl ether at pH 6 and the analysis of the extract by reversed-phase HPLC with solvent programming and detection at 365 nm. The quantitation ranges for 13-cis-RA and 4-oxo-13-cis-RA are 10--2000 and 50--2000 ng/ml of blood, respectively. The method also provides estimates of the concentrations of all-trans-RA and 4-oxo-all-trans-RA. The mean intra- and inter-assay variabilities for all four compounds were 6% or less. The method separates 13-cis-RA and 4-oxo-13-cis-RA from 9-cis-RA, all-trans-RA, 4-oxo-all-trans-RA, and some other possible metabolites, such as hydroxy and epoxy retinoic acids. The method has been successfully applied to the analyses of over 1200 blood samples from four 13-cis-RA clinical studies.

Direct and sensitive determination of glyphosate and aminomethylphosphonic acid in environmental water samples by high performance liquid chromatography coupled to electrospray tandem mass spectrometry.

PubMed

Guo, Hongyue; Riter, Leah S; Wujcik, Chad E; Armstrong, Daniel W

2016-04-22

A novel method based on high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) was developed for the sensitive determination of glyphosate and its major degradation product, AMPA in environmental water samples. The method involves the use of MS compatible mobile phases (0.1% formic acid in water and acetonitrile) for HPLC and direct analysis of water samples without sample derivatization. The method has been validated in different types of water matrices (drinking, surface and groundwater) by accuracy and precision studies with samples spiked at 0.1, 7.5 and 90 ppb. All mean accuracy values ranged from 85% to 112% for glyphosate and AMPA using both primary and secondary quantitative ion transitions (RSD ≤ 10%). Moreover, both primary and secondary ion transitions for glyphosate and AMPA can achieve the quantitation limits at 0.1 ppb. The linear dynamic range of the calibration curves were from 0.1 to 100 ppb for each analyte at each ion transitions with correlation coefficient higher than 0.997. Copyright © 2016 Elsevier B.V. All rights reserved.

Development of a near-infrared spectroscopy method (NIRS) for fast analysis of total, indolic, aliphatic and individual glucosinolates in new bred open pollinating genotypes of broccoli (Brassica oleracea convar. botrytis var. italica).

PubMed

Sahamishirazi, Samira; Zikeli, Sabine; Fleck, Michael; Claupein, Wilhelm; Graeff-Hoenninger, Simone

2017-10-01

This study describes the development of near-infrared spectroscopy (NIRS) calibration to determine individual and total glucosinolates (GSLs) content of 12 new-bred open-pollinating genotypes of broccoli (Brassica oleracea convar. botrytis var. italica). Six individual GSLs were identified using high-performance-liquid chromatography (HPLC). The NIRS calibration was established based on modified partial least squares regression with reference values of HPLC. The calibration was analyzed using coefficient of determination in prediction (R 2 ) and ratio of preference of determination (RPD). Large variation occurred in the calibrations, R 2 and RPD due to the variability of the samples. Derived calibrations for total-GSLs, aliphatic-GSLs, glucoraphanin and 4-methoxyglucobrassicin were quantitative with a high accuracy (RPD=1.36, 1.65, 1.63, 1.11) while, for indole-GSLs, glucosinigrin, glucoiberin, glucobrassicin and 1-methoxyglucobrassicin were more qualitative (RPD=0.95, 0.62, 0.67, 0.81, 0.56). Overall, the results indicated NIRS has a good potential to determine different GSLs in a large sample pool of broccoli quantitatively and qualitatively. Copyright © 2017 Elsevier Ltd. All rights reserved.

Time-Resolved Fluorescent Immunochromatography of Aflatoxin B1 in Soybean Sauce: A Rapid and Sensitive Quantitative Analysis.

PubMed

Wang, Du; Zhang, Zhaowei; Li, Peiwu; Zhang, Qi; Zhang, Wen

2016-07-14

Rapid and quantitative sensing of aflatoxin B1 with high sensitivity and specificity has drawn increased attention of studies investigating soybean sauce. A sensitive and rapid quantitative immunochromatographic sensing method was developed for the detection of aflatoxin B1 based on time-resolved fluorescence. It combines the advantages of time-resolved fluorescent sensing and immunochromatography. The dynamic range of a competitive and portable immunoassay was 0.3-10.0 µg·kg(-1), with a limit of detection (LOD) of 0.1 µg·kg(-1) and recoveries of 87.2%-114.3%, within 10 min. The results showed good correlation (R² > 0.99) between time-resolved fluorescent immunochromatographic strip test and high performance liquid chromatography (HPLC). Soybean sauce samples analyzed using time-resolved fluorescent immunochromatographic strip test revealed that 64.2% of samples contained aflatoxin B1 at levels ranging from 0.31 to 12.5 µg·kg(-1). The strip test is a rapid, sensitive, quantitative, and cost-effective on-site screening technique in food safety analysis.

An HPLC method for determination of azadirachtin residues in bovine muscle.

PubMed

Gai, María Nella; Álvarez, Christian; Venegas, Raúl; Morales, Javier

2011-04-01

A high-performance liquid chromatography (HPLC) method for the determination of azadirachtin (A and B) residues in bovine muscle has been developed. Azadirachtin is a neutral triterpene and chemotherapeutic agent effective in controlling some pest flies in horses, stables, horns and fruit. The actual HPLC method uses an isocratic elution and UV detection. Liquid-liquid extraction and solid-phase purification was used for the clean-up of the biological matrix. The chromatographic determination of these components is achieved using a C18 analytical column with water-acetonitrile mixture (27.5:72.5, v/v) as mobile phase, 1 mL/min as flow rate, 45 °C column temperature and UV detector at 215 nm. The azadirachtin peaks are well resolved and free of interference from matrix components. The extraction and analytical method developed in this work allows the quantitation of azadirachtin with precision and accuracy, establishing a lower limit of quantitation of azadirachtin, extracted from the biological matrix.

Mass-spectrometric analysis of hydroperoxy- and hydroxy-derivatives of cardiolipin and phosphatidylserine in cells and tissues induced by pro-apoptotic and pro-inflammatory stimuli

PubMed Central

Tyurin, Vladimir A.; Tyurina, Yulia Y.; Jung, Mi-Yeon; Tungekar, Muhammad A.; Wasserloos, Karla J.; Bayir, Hülya; Greenberger, Joel S.; Kochanek, Patrick M.; Shvedova, Anna A.; Pitt, Bruce; Kagan, Valerian E.

2009-01-01

Oxidation of two anionic phospholipids - cardiolipin (CL) in mitochondria and phosphatidylserine (PS) in extramitochondrial compartments - are important signaling events, particularly during the execution of programmed cell death and clearance of apoptotic cells. Quantitative analysis of CL and PS oxidation products is central to understanding their molecular mechanisms of action. We combined the identification of diverse phospholipid molecular species by ESI-MS with quantitative assessments of lipid hydroperoxides using a fluorescence HPLC-based protocol. We characterized CL and PS oxidation products formed in a model system (cyt c/H2O2), in apoptotic cells (neurons, pulmonary artery endothelial cells) and mouse lung under inflammatory/oxidative stress conditions (hyperoxia, inhalation of single walled carbon nanotubes). Our results demonstrate the usefulness of this approach for quantitative assessments, identification of individual molecular species and structural characterization of anionic phospholipids that are involved in oxidative modification in cells and tissues. PMID:19328050

Salting-Out Assisted Liquid-Liquid Extraction for Quantification of Febuxostat in Plasma Using RP-HPLC and Its Pharmacokinetic Application.

PubMed

Tandel, Devang; Shah, Purvi; Patel, Kalpana; Thakkar, Vaishali; Patel, Kirti; Gandhi, Tejal

2016-11-01

A rapid and sensitive reversed-phase high-performance liquid chromatography (HPLC) method using novel salting-out assisted liquid-liquid extraction technique has been developed for the quantitative determination of febuxostat (FEB), used for the treatment of gout, in rat plasma. The method was validated according to US FDA guideline. Separation was achieved using a Phenomenex Luna-C 18 (250 × 4.60 mm, 5 µm) column and mobile phase composed of potassium dihydrogen orthophosphate buffer 25 mM, adjusted to pH 6.8 with triethylamine:methanol in a ratio of 35:65 (v/v) showing retention time 5.56 and 8.86 min for FEB and internal standard, respectively. The optimal salting-out parameters; 1 mL of acetonitrile and 200 µL of 2 M ammonium acetate salt showed extraction recovery >90% for FEB from plasma. This extraction procedure afforded clear samples resulting in convenient and cost-saving procedure and showed good linear relationship (r > 0.9997) between peak area ratio and concentration from 0.3 to 20 µg/mL. The results of pharmacokinetic study showed that absorption profile of spherical agglomerate of FEB compared to marketed formulation was higher indicating greater systemic absorption. In conclusion, the developed SALLE-HPLC method with simple ultraviolet detection offered a number of advantages including good quantitative ability, wide linear range, high recovery, short analysis time as well as low cost. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Quantitative determination of regorafenib and its two major metabolites in human plasma with high-performance liquid chromatography and ultraviolet detection.

PubMed

Fujita, Kazuma; Miura, Masatomo; Shibata, Hiroyuki

2016-10-01

A simple, highly sensitive and specific high-performance liquid chromatography (HPLC) method was developed for the simultaneous quantitation of regorafenib, N-oxidemetabolite (M-2) and the desmethyl N-oxide metabolite (M-5) in human plasma. Regorafenib, M-2, M-5 and the internal standard sorafenib were separated using a mobile phase of 0.5% KH2 PO4 (pH 3.5)-acetonitrile (30:70, v/v), on a Capcell PAK MG II column at a flow rate of 0.5 mL/min and measurement at UV 260 nm. The lower limits of quantification for regorafenib, M-2 and M-5 were 10 ng/mL for each analyte. A procedure using solid-phase extraction required only a small amount of plasma (100 μL) for one analysis while providing high extraction recovery (>81% for all compounds) and good selectivity. Coefficients of variation for intra- and inter-day assays were <12.2% for regorafenib, <12.3% for M-2 and <15.1% for M-5. Accuracies for intra- and inter-day assays were <9.4% for regorafenib, <8.0% for M-2 and <12.8% for M-5 over a linear range from 10 to 10,000 ng/mL. This HPLC assay is suitable for clinical pharmacokinetic studies of regorafenib. The present HPLC method is currently in use for our observational studies of patients under treatment. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Quantitative Thin-Layer Chromatography/Mass Spectrometry Analysis of Caffeine Using a Surface Sampling Probe Electrospray Ionization Tandem Mass Spectrometry System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ford, Michael J; Deibel, Michael A.; Tomkins, Bruce A

Quantitative determination of caffeine on reversed-phase C8 thin-layer chromatography plates using a surface sampling electrospray ionization system with tandem mass spectrometry detection is reported. The thin-layer chromatography/electrospray tandem mass spectrometry method employed a deuterium-labeled caffeine internal standard and selected reaction monitoring detection. Up to nine parallel caffeine bands on a single plate were sampled in a single surface scanning experiment requiring 35 min at a surface scan rate of 44 {mu}m/s. A reversed-phase HPLC/UV caffeine assay was developed in parallel to assess the mass spectrometry method performance. Limits of detection for the HPLC/UV and thin-layer chromatography/electrospray tandem mass spectrometry methodsmore » determined from the calibration curve statistics were 0.20 ng injected (0.50 {mu}L) and 1.0 ng spotted on the plate, respectively. Spike recoveries with standards and real samples ranged between 97 and 106% for both methods. The caffeine content of three diet soft drinks (Diet Coke, Diet Cherry Coke, Diet Pepsi) and three diet sport drinks (Diet Turbo Tea, Speed Stack Grape, Speed Stack Fruit Punch) was measured. The HPLC/UV and mass spectrometry determinations were in general agreement, and these values were consistent with the quoted values for two of the three diet colas. In the case of Diet Cherry Coke and the diet sports drinks, the determined caffeine amounts using both methods were consistently higher (by 8% or more) than the literature values.« less

Simple, fast and reliable liquid chromatographic and spectrophotometric methods for the determination of theophylline in urine, saliva and plasma samples.

PubMed

Charehsaz, Mohammad; Gürbay, Aylin; Aydin, Ahmet; Sahin, Gönül

2014-01-01

In this study, a high-performance liquid chromatographic method (HPLC) and UV spectrophotometric method were developed, validated and applied for the determination of theophylline in biological fluids. Liquid- liquid extraction is performed for isolation of the drug and elimination of plasma and saliva interferences. Urine samples were applied without any extraction. The chromatographic separation was achieved on a C18 column by using 60:40 methanol:water as mobile phase under isocratic conditions at a flow rate of 0.75 mL/min with UV detection at 280 nm in HPLC method. UV spectrophotometric analysis was performed at 275 nm. the limit of quantification: 1.1 µg/mL for urine, 1.9 µg/mL for saliva, 3.1 µg/mL for plasma; recovery: 94.85% for plasma, 100.45% for saliva, 101.39% for urine; intra-day precision: 0.22-2.33%, inter-day precision: 3.17-13.12%. Spectrophotometric analysis results were as follows: the limit of quantitation: 5.23 µg/mL for plasma, 8.7 µg/mL for urine; recovery: 98.27% for plasma, 95.25% for urine; intra-day precision: 2.37 - 3.00%, inter-day precision: 5.43-7.91%. It can be concluded that this validated HPLC method is easy, precise, accurate, sensitive and selective for determination of theophylline in biological samples. Also spectrophotometric analysis can be used where it can be applicable.

Topiramate: A Review of Analytical Approaches for the Drug Substance, Its Impurities and Pharmaceutical Formulations.

PubMed

Pinto, Eduardo Costa; Dolzan, Maressa Danielli; Cabral, Lucio Mendes; Armstrong, Daniel W; de Sousa, Valéria Pereira

2016-02-01

An important step during the development of high-performance liquid chromatography (HPLC) methods for quantitative analysis of drugs is choosing the appropriate detector. High sensitivity, reproducibility, stability, wide linear range, compatibility with gradient elution, non-destructive detection of the analyte and response unaffected by changes in the temperature/flow are some of the ideal characteristics of a universal HPLC detector. Topiramate is an anticonvulsant drug mainly used for the treatment of different types of seizures and prophylactic treatment of migraine. Different analytical approaches to quantify topiramate by HPLC have been described because of the lack of chromophoric moieties on its structure, such as derivatization with fluorescent moieties and UV-absorbing moieties, conductivity detection, evaporative light scattering detection, refractive index detection, chemiluminescent nitrogen detection and MS detection. Some methods for the determination of topiramate by capillary electrophoresis and gas chromatography have also been published. This systematic review provides a description of the main analytical methods presented in the literature to analyze topiramate in the drug substance and in pharmaceutical formulations. Each of these methods is briefly discussed, especially considering the detector used with HPLC. In addition, this article presents a review of the data available regarding topiramate stability, degradation products and impurities. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Quantitative determination of flavonoids by column high-performance liquid chromatography with mass spectrometry and ultraviolet absorption detection in Artemisia afra and comparative studies with various species of Artemisia plants.

PubMed

Avula, Bharathi; Wang, Yan-Hong; Smillie, Troy J; Mabusela, Wilfred; Vincent, Leszek; Weitz, Frans; Khan, Ikhlas A

2009-01-01

A simple and specific analytical method for the quantitative determination of flavonoids from the aerial parts of the Artemisia afra plant samples was developed. By column high-performance liquid chromatography (HPLC) with UV absorption and mass spectrometry (MS) detection, separation was achieved on a reversed-phase octadecylsilyl (C18) column with water, methanol, and acetonitrile, all containing 0.1% acetic acid, as the mobile phase. These methods were used to analyze various species of Artemisia plant samples. The wavelength used for quantification of flavonoids with the diode array detector was 335 nm. The limits of detection (LOD) by HPLC/MS were found to be 7.5, 7.5, 10, 2.0, and 2.0 ng/mL; and by LC-UV the LODs were 500, 500, 500, 300, and 300 ng/mL for apigenin, chrysoeriol, tamarixetin, acacetin, and genkwanin, respectively. The HPLC/MS method was found to be 50-150 times more sensitive than the HPLC-UV method. HPLC/MS coupled with an electrospray ionization interface is described for the identification and quantification of flavonoids in various plant samples. This method involved the use of the [M+H]+ ions of the compounds at mass-to-charge ratio of 1.0606, 301.0712, 317.0661, 285.0763, and 285.0763 (calculated mass), respectively, in the positive ion mode with extractive ion monitoring.

A new technique for collection, concentration and determination of gaseous tropospheric formaldehyde

NASA Astrophysics Data System (ADS)

Cofer, Wesley R.; Edahl, Robert A.

This article describes an improved technique for making in situ measurements of gaseous tropospheric formaldehyde (CH 2O). The new technique is based on nebulization/reflux principles that have proved very effective in quantitatively scrubbing water soluble trace gases (e.g. CH 2O) into aqueous mediums, which are subsequently analyzed. Atmospheric formaldehyde extractions and analyses have been performed with the nebulization/reflux concentrator using an acidified dinitrophenylhydrazine solution that indicate that quantitative analysis of CH 2O at global background levels (˜ 0.1 ppbv) is feasible with 20-min extractions. Analysis of CH 2O, once concentrated, is accomplished using high performance liquid chromatography (HPLC) with ultraviolet photometric detection. The CH 2O-hydrazone derivative, produced by the reaction of 2,4-dinitrophenylhydrazine in H 2SO 4 acidified aqueous solution, is detected as CH 2O.

Reverse phase HPLC method for detection and quantification of lupin seed γ-conglutin.

PubMed

Mane, Sharmilee; Bringans, Scott; Johnson, Stuart; Pareek, Vishnu; Utikar, Ranjeet

2017-09-15

A simple, selective and accurate reverse phase HPLC method was developed for detection and quantitation of γ-conglutin from lupin seed extract. A linear gradient of water and acetonitrile containing trifluoroacetic acid (TFA) on a reverse phase column (Agilent Zorbax 300SB C-18), with a flow rate of 0.8ml/min was able to produce a sharp and symmetric peak of γ-conglutin with a retention time at 29.16min. The identity of γ-conglutin in the peak was confirmed by mass spectrometry (MS/MS identification) and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) analysis. The data obtained from MS/MS analysis was matched against the specified database to obtain the exact match for the protein of interest. The proposed method was validated in terms of specificity, linearity, sensitivity, precision, recovery and accuracy. The analytical parameters revealed that the validated method was capable of selectively performing a good chromatographic separation of γ-conglutin from the lupin seed extract with no interference of the matrix. The detection and quantitation limit of γ-conglutin were found to be 2.68μg/ml and 8.12μg/ml respectively. The accuracy (precision and recovery) analysis of the method was conducted under repeatable conditions on different days. Intra-day and inter-day precision values less than 0.5% and recovery greater than 97% indicated high precision and accuracy of the method for analysis of γ-conglutin. The method validation findings were reproducible and can be successfully applied for routine analysis of γ-conglutin from lupin seed extract. Copyright © 2017 Elsevier B.V. All rights reserved.

A simple method for plasma total vitamin C analysis suitable for routine clinical laboratory use.

PubMed

Robitaille, Line; Hoffer, L John

2016-04-21

In-hospital hypovitaminosis C is highly prevalent but almost completely unrecognized. Medical awareness of this potentially important disorder is hindered by the inability of most hospital laboratories to determine plasma vitamin C concentrations. The availability of a simple, reliable method for analyzing plasma vitamin C could increase opportunities for routine plasma vitamin C analysis in clinical medicine. Plasma vitamin C can be analyzed by high performance liquid chromatography (HPLC) with electrochemical (EC) or ultraviolet (UV) light detection. We modified existing UV-HPLC methods for plasma total vitamin C analysis (the sum of ascorbic and dehydroascorbic acid) to develop a simple, constant-low-pH sample reduction procedure followed by isocratic reverse-phase HPLC separation using a purely aqueous low-pH non-buffered mobile phase. Although EC-HPLC is widely recommended over UV-HPLC for plasma total vitamin C analysis, the two methods have never been directly compared. We formally compared the simplified UV-HPLC method with EC-HPLC in 80 consecutive clinical samples. The simplified UV-HPLC method was less expensive, easier to set up, required fewer reagents and no pH adjustments, and demonstrated greater sample stability than many existing methods for plasma vitamin C analysis. When compared with the gold-standard EC-HPLC method in 80 consecutive clinical samples exhibiting a wide range of plasma vitamin C concentrations, it performed equivalently. The easy set up, simplicity and sensitivity of the plasma vitamin C analysis method described here could make it practical in a normally equipped hospital laboratory. Unlike any prior UV-HPLC method for plasma total vitamin C analysis, it was rigorously compared with the gold-standard EC-HPLC method and performed equivalently. Adoption of this method could increase the availability of plasma vitamin C analysis in clinical medicine.

Sensitive method for the quantitation of droloxifene in plasma and serum by high-performance liquid chromatography employing fluorimetric detection.

PubMed

Tess, D A; Cole, R O; Toler, S M

1995-12-15

A simple and highly sensitive reversed-phase fluorimetric HPLC method for the quantitation of droloxifene from rat, monkey, and human plasma as well as human serum is described. This assay employs solid-phase extraction and has a dynamic range of 25 to 10,000 pg/ml. Sample extraction (efficiencies > 86%) was accomplished using a benzenesulfonic acid (SCX) column with water and methanol rinses. Droloxifene and internal standard were eluted with 1 ml of 3.5% (v/v) ammonium hydroxide (30%) in methanol. Samples were quantitated using post-column UV-photochemical cyclization coupled with fluorimetric detection with excitation and emission wavelengths of 260 nm and 375 nm, respectively. Relative ease of sample extraction and short run times allow for the analysis of approximately 100 samples per day.

Rapid qualitative and quantitative analysis of opiates in extract of poppy head via FTIR and chemometrics: towards in-field sensors.

PubMed

Turner, Nicholas W; Cauchi, Michael; Piletska, Elena V; Preston, Christopher; Piletsky, Sergey A

2009-07-15

Identification and quantification of the opiates morphine and thebaine has been achieved in three commercial poppy cultivars using FTIR-ATR spectroscopy, from a simple and rapid methanolic extraction, suitable for field analysis. The limits of detection were 0.13 mg/ml (0.013%, w/v) and 0.3 mg/ml (0.03%, w/v) respectively. The concentrations of opiates present were verified with HPLC-MS. The chemometrics has been used to identify specific "signature" peaks in the poppy IR spectra for characterisation of cultivar by its unique fingerprint offering a potential forensic application in opiate crop analysis.

Determination of CMPO using HPLC -UV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gracy Elias; Gary S. Groenewold; Bruce J. Mincher

Octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) is an extractant proposed for selective separation of radionuclide metals from used nuclear fuel solutions using solvent extraction. Radiolysis reactions can degrade CMPO and reduce separation performance and hence methods for measuring concentration of CMPO and identifying degradation products are needed. A novel high performance liquid chromatography (HPLC) method employing ultraviolet detection (UV) was developed to detect and quantitate CMPO in dodecane. Some radiolysis products in gamma and alpha irradiated CMPO solutions were identified using HPLC/electrospray ionization-mass spectrometry (ESI-MS). Validation data indicated that the HPLC-UV method for CMPO determination provided good linearity, sensitivity, procedure accuracy and systemmore » precision. CMPO-nitric acid complexes were also identified, that account for the apparent loss of CMPO in acidic environment, independent of irradiation.« less

Analysis of co-eluted isomers of high-molecular weight polycyclic aromatic hydrocarbons in high performance liquid chromatography fractions via solid-phase nanoextraction and time-resolved Shpol'skii spectroscopy.

PubMed

Wilson, Walter B; Campiglia, Andres D

2011-09-28

We present an accurate method for the determination of isomers of high-molecular weight polycyclic aromatic hydrocarbons co-eluted in HPLC fractions. The feasibility of this approach is demonstrated with two isomers of molecular weight 302 with identical mass fragmentation patterns, namely dibenzo[a,i]pyrene and naphtho[2,3-a]pyrene. Qualitative and quantitative analysis is carried out via laser-excited time-resolved Shpol'skii spectroscopy at liquid helium temperature. Unambiguous identification of co-eluted isomers is based on their characteristic 4.2 K line-narrowed spectra in n-octane as well as their fluorescence lifetimes. Pre-concentration of HPLC fractions prior to spectroscopic analysis is performed with the aid of gold nanoparticles via an environmentally friendly procedure. In addition to the two co-eluted isomers, the analytical figures of merit of the entire procedure were evaluated with dibenzo[a,l]pyrene, dibenzo[a,h]pyrene and dibenzo[a,e]pyrene. The analytical recoveries from drinking water samples varied between 98.2±5.5 (dibenzo[a,l]pyrene) and 102.7±3.2% (dibenzo[a,i]pyrene). The limits of detection ranged from 51.1 ng L(-1) (naphtho[2,3-a]pyrene) to 154 ng L(-1) (dibenzo[a,e]pyrene). The excellent analytical figures of merit associated to its HPLC compatibility makes this approach an attractive alternative for the analysis of co-eluted isomers with identical mass spectra. Copyright © 2011 Elsevier B.V. All rights reserved.

Cluster analysis of historical and modern hard red spring wheat cultivars based on parentage and HPLC analysis of gluten forming proteins

USDA-ARS?s Scientific Manuscript database

In this study, 30 hard red spring (HRS) wheat cultivars released between 1910 and 2013 were analyzed to determine how they cluster in terms of parentage and protein data, analyzed by reverse-phase HPLC (RP-HPLC) of gliadins, and size-exclusion HPLC (SE-HPLC) of unreduced proteins. Dwarfing genes in...

Quantitation of sugar content in pyrolysis liquids after acid hydrolysis using high-performance liquid chromatography without neutralization.

PubMed

Johnston, Patrick A; Brown, Robert C

2014-08-13

A rapid method for the quantitation of total sugars in pyrolysis liquids using high-performance liquid chromatography (HPLC) was developed. The method avoids the tedious and time-consuming sample preparation required by current analytical methods. It is possible to directly analyze hydrolyzed pyrolysis liquids, bypassing the neutralization step usually required in determination of total sugars. A comparison with traditional methods was used to determine the validity of the results. The calibration curve coefficient of determination on all standard compounds was >0.999 using a refractive index detector. The relative standard deviation for the new method was 1.13%. The spiked sugar recoveries on the pyrolysis liquid samples were between 104 and 105%. The research demonstrates that it is possible to obtain excellent accuracy and efficiency using HPLC to quantitate glucose after acid hydrolysis of polymeric and oligomeric sugars found in fast pyrolysis bio-oils without neutralization.

Partial Analysis of Insta-Foam

NASA Technical Reports Server (NTRS)

Chou, L. W.

1983-01-01

Insta-Foam, used as a thermal insulator for the non-critical area of the external tank during the prelaunch phase to minimize icing, is a two-component system. Component A has polyisocyanates, blowing agents, and stabilizers; Component B has the polyols, catalysts, blowing agents, stabilizers and fire retardant. The blowing agents are Freon 11 and Freon 12, the stabilizers are silicone surfactants, the catalysts are tertiary amines, and the fire retardant is tri-(beta-chloro-isopropyl) phosphate (PCF). High performance liquid chromatography (HPLC) was quantitatively identified polyols and PFC.

Sources and concentrations of aldehydes and ketones in indoor environments in the UK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crump, D.R.; Gardiner, D.

1989-01-01

Individual aldehydes and ketones can be separated, identified and quantitatively estimated by trapping the 2,4-dinitrophenylhydrazine (DNPH) derivatives and analysis by HPLC. Appropriate methods and detection limits are reported. Many sources of formaldehyde have been identified by this means and some are found to emit other aldehydes and ketones. The application of this method to determine the concentration of these compounds in the atmospheres of buildings is described and the results compared with those obtained using chromotropic acid or MBTH.

Determination of alkylphenols and alkylphenol mono- and diethoxylates in environmental samples by high-performance liquid chromatography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahel, M.; Giger, W.

1985-07-01

A routine method is described for the quantitative determination of 4-nonylphenol (NP) and 4-nonylphenol mono-(NP1EO) and diethoxylate (NP2EO) in samples from wastewater and sludge treatment and from the aquatic environment. An exhaustive steam-distillation/solvent-extraction procedure was employed to enrich the analytes from aqueous and solid samples. Quantitative determinations were performed by normal-phase high-performance liquid chromatography (HP-LC) using aminosilica columns. Relative standard deviations were 3.0-4.4% in a river water containing 3.9 ..mu..g/L NP, 23.4 ..mu..g/L NP1EO, and 9.4 ..mu..g/L NP2EO. A digested sewage sludge with 1.6 g of NP/kg of dry matter was analyzed with a relative standard deviation of 3.7%. Recoveriesmore » were higher than 80%, and the estimated detection limit in water samples was 0.5 ..mu..g/L. Reversed-phase HPLC on octylsilica provided complementary qualitative data, particularly on homologous alkylphenolic compounds. Good agreement was found between quantitative determinations by HPLC and by high-resolution gas chromatography with flame ionization detection and directly coupled mass spectrometry. Municipal wastewater effluents, sewage sludges, and natural waters were analyzed to demonstrate the method's broad applicability. 19 references, 4 tables, 4 figures.« less

Quality Evaluation of the Traditional Medicine Majun Mupakhi ELA via Chromatographic Fingerprinting Coupled with UHPLC-DAD-Quadrupole-Orbitrap-MS and the Antioxidant Activity In Vitro

PubMed Central

Reheman, Ayinuer; Ma, Qing Ling; Nijat, Dilaram; Abdulla, Rahima

2018-01-01

By merging a high-performance liquid chromatography diode array detector (HPLC-DAD) method with high-performance thin-layer chromatography (HPTLC), an assay was developed for chemical fingerprinting and quantitative analysis of traditional medicine Majun Mupakhi ELA (MME), and constituent compounds were identified using HPLC coupled with UHPLC-DAD-Quadrupole-Orbitrap-MS method. In addition, the antioxidant capacity of MME was assessed based on the ability of components to scavenge radicals using in vitro method. Using a HPLC-DAD method with HPTLC easily validated the chemical fingerprinting results and quantified three characteristic components, namely, gallic acid (1), daidzein (2), and icariin (3), in commercial MMEs. The three compounds presented excellent regression values (R2 = 0.9999) in the ranges of the test and the method recovery was in the range from 100.49% to 100.68%. The fingerprints had 27 common characteristic peaks, of which 13 were verified by rapid UHPLC-DAD-Q-Orbitrap-MS analysis. In vitro antioxidant assays rapidly assessed and contrasted antioxidant activity or the free radical scavenging activity of the main polyphenolic classes in MMEs, and the antioxidant capacity was mostly affected by the presence of gallic acid. Thus, this study establishes a powerful and meaningful approach for MME quality control and for assessing in vitro antioxidant activity. PMID:29692853

Quality Evaluation of the Traditional Medicine Majun Mupakhi ELA via Chromatographic Fingerprinting Coupled with UHPLC-DAD-Quadrupole-Orbitrap-MS and the Antioxidant Activity In Vitro.

PubMed

Reheman, Ayinuer; Aisa, Haji Akber; Ma, Qing Ling; Nijat, Dilaram; Abdulla, Rahima

2018-01-01

By merging a high-performance liquid chromatography diode array detector (HPLC-DAD) method with high-performance thin-layer chromatography (HPTLC), an assay was developed for chemical fingerprinting and quantitative analysis of traditional medicine Majun Mupakhi ELA (MME), and constituent compounds were identified using HPLC coupled with UHPLC-DAD-Quadrupole-Orbitrap-MS method. In addition, the antioxidant capacity of MME was assessed based on the ability of components to scavenge radicals using in vitro method. Using a HPLC-DAD method with HPTLC easily validated the chemical fingerprinting results and quantified three characteristic components, namely, gallic acid (1), daidzein (2), and icariin (3), in commercial MMEs. The three compounds presented excellent regression values ( R 2 = 0.9999) in the ranges of the test and the method recovery was in the range from 100.49% to 100.68%. The fingerprints had 27 common characteristic peaks, of which 13 were verified by rapid UHPLC-DAD-Q-Orbitrap-MS analysis. In vitro antioxidant assays rapidly assessed and contrasted antioxidant activity or the free radical scavenging activity of the main polyphenolic classes in MMEs, and the antioxidant capacity was mostly affected by the presence of gallic acid. Thus, this study establishes a powerful and meaningful approach for MME quality control and for assessing in vitro antioxidant activity.

OnpA, an Unusual Flavin-Dependent Monooxygenase Containing a Cytochrome b5 Domain

PubMed Central

Xiao, Yi; Liu, Ting-Ting; Dai, Hui; Zhang, Jun-Jie; Liu, Hong; Tang, Huiru; Leak, David J.

2012-01-01

ortho-Nitrophenol 2-monooxygenase (EC 1.14.13.31) from Alcaligenes sp. strain NyZ215 catalyzes monooxygenation of ortho-nitrophenol to form catechol via ortho-benzoquinone. Sequence analysis of this onpA-encoded enzyme revealed that it contained a flavin-binding monooxygenase domain and a heme-binding cytochrome b5 domain. OnpA was purified to homogeneity as a His-tagged protein and was considered a monomer, as determined by gel filtration. FAD and heme were identified by high-performance liquid chromatography (HPLC) and HPLC-mass spectrometry (HPLC-MS) as cofactors in this enzyme, and quantitative analysis indicated that 1 mol of the purified recombinant OnpA contained 0.66 mol of FAD and 0.20 mol of heme. However, the enzyme activity of OnpA was increased by 60% and 450% after addition of FAD and hemin, respectively, suggesting that the optimal stoichiometry was 1:1:1. In addition, site-directed mutagenesis experiments confirmed that two highly conserved histidines located in the cytochrome b5 domain were associated with binding of the heme, and the cytochrome b5 domain was involved in the OnpA activity. These results indicate that OnpA is an unusual FAD-dependent monooxygenase containing a fused cytochrome b5 domain that is essential for its activity. Therefore, we here demonstrate a link between cytochrome b5 and flavin-dependent monooxygenases. PMID:22267507

Quantitative determination of the major saponin mixture bacoside A in Bacopa monnieri by HPLC.

PubMed

Deepak, M; Sangli, G K; Arun, P C; Amit, A

2005-01-01

Bacoside A, the putative bioactive component of the Indian medicinal plant Bacopa monnieri, was found to be a mixture of saponins with bacoside A3 (1), bacopaside II (2), jujubogenin isomer of bacopasaponin C (3) and bacopasaponin C (4) as major constituents. An HPLC method together with an optimised extraction procedure was developed for the estimation of 1-4 in B. monnieri to enable standardisation of the latter. Concentration ranges of the analytes in samples of B. monnieri collected from different regions of India were 0.14-0.85% (w/w) (1), 0.12-0.69% (2), 0.05-0.72% (3) and 0.05-0.44% (4). The importance of using bacoside A, with known concentrations of 1-4, as a reference standard for the routine analysis of B. monnieri is highlighted. Two common flavonoids, luteolin and apigenin, were present in all samples of B. monnieri.

Comparing monolithic and fused core HPLC columns for fast chromatographic analysis of fat-soluble vitamins.

PubMed

Kurdi, Said El; Muaileq, Dina Abu; Alhazmi, Hassan A; Bratty, Mohammed Al; Deeb, Sami El

2017-06-27

HPLC stationary phases of monolithic and fused core type can be used to achieve fast chromatographic separation as an alternative to UPLC. In this study, monolithic and fused core stationary phases are compared for fast separation of four fat-soluble vitamins. Three new methods on the first and second generation monolithic silica RP-18e columns and a fused core pentafluoro-phenyl propyl column were developed. Application of three fused core columns offered comparable separations of retinyl palmitate, DL-α-tocopheryl acetate, cholecalciferol and menadione in terms of elution speed and separation efficiency. Separation was achieved in approx. 5 min with good resolution (Rs > 5) and precision (RSD ≤ 0.6 %). Monolithic columns showed, however, a higher number of theoretical plates, better precision and lower column backpressure than the fused core column. The three developed methods were successfully applied to separate and quantitate fat-soluble vitamins in commercial products.

Quantitative estimation of itopride hydrochloride and rabeprazole sodium from capsule formulation.

PubMed

Pillai, S; Singhvi, I

2008-09-01

Two simple, accurate, economical and reproducible UV spectrophotometric methods and one HPLC method for simultaneous estimation of two component drug mixture of itopride hydrochloride and rabeprazole sodium from combined capsule dosage form have been developed. First developed method involves formation and solving of simultaneous equations using 265.2 nm and 290.8 nm as two wavelengths. Second method is based on two wavelength calculation, wavelengths selected for estimation of itopride hydrochloride was 278.0 nm and 298.8 nm and for rabeprazole sodium 253.6 nm and 275.2 nm. Developed HPLC method is a reverse phase chromatographic method using phenomenex C(18) column and acetonitrile: phosphate buffer (35:65 v/v) pH 7.0 as mobile phase. All developed methods obey Beer's law in concentration range employed for respective methods. Results of analysis were validated statistically and by recovery studies.

Quantitative Estimation of Itopride Hydrochloride and Rabeprazole Sodium from Capsule Formulation

PubMed Central

Pillai, S.; Singhvi, I.

2008-01-01

Two simple, accurate, economical and reproducible UV spectrophotometric methods and one HPLC method for simultaneous estimation of two component drug mixture of itopride hydrochloride and rabeprazole sodium from combined capsule dosage form have been developed. First developed method involves formation and solving of simultaneous equations using 265.2 nm and 290.8 nm as two wavelengths. Second method is based on two wavelength calculation, wavelengths selected for estimation of itopride hydrochloride was 278.0 nm and 298.8 nm and for rabeprazole sodium 253.6 nm and 275.2 nm. Developed HPLC method is a reverse phase chromatographic method using phenomenex C18 column and acetonitrile: phosphate buffer (35:65 v/v) pH 7.0 as mobile phase. All developed methods obey Beer's law in concentration range employed for respective methods. Results of analysis were validated statistically and by recovery studies. PMID:21394269

HPLC method development for evolving applications in the pharmaceutical industry and nanoscale chemistry

NASA Astrophysics Data System (ADS)

Castiglione, Steven Louis

As scientific research trends towards trace levels and smaller architectures, the analytical chemist is often faced with the challenge of quantitating said species in a variety of matricies. The challenge is heightened when the analytes prove to be potentially toxic or possess physical or chemical properties that make traditional analytical methods problematic. In such cases, the successful development of an acceptable quantitative method plays a critical role in the ability to further develop the species under study. This is particularly true for pharmaceutical impurities and nanoparticles (NP). The first portion of the research focuses on the development of a part-per-billion level HPLC method for a substituted phenazine-class pharmaceutical impurity. The development of this method was required due to the need for a rapid methodology to quantitatively determine levels of a potentially toxic phenazine moiety in order to ensure patient safety. As the synthetic pathway for the active ingredient was continuously refined to produce progressively lower amounts of the phenazine impurity, the approach for increasingly sensitive quantitative methods was required. The approaches evolved across four discrete methods, each employing a unique scheme for analyte detection. All developed methods were evaluated with regards to accuracy, precision and linear adherence as well as ancillary benefits and detriments -- e.g., one method in this evolution demonstrated the ability to resolve and detect other species from the phenazine class. The second portion of the research focuses on the development of an HPLC method for the quantitative determination of NP size distributions. The current methodology for the determination of NP sizes employs tunneling electron microscopy (TEM), which requires sample drying without particle size alteration and which, in many cases, may prove infeasible due to cost or availability. The feasibility of an HPLC method for NP size characterizations evolved across three methods, each employing a different approach for size resolution. These methods were evaluated primarily for sensitivity, which proved to be a substantial hurdle to further development, but does not appear to deter future research efforts.

Stability Test and Quantitative and Qualitative Analyses of the Amino Acids in Pharmacopuncture Extracted from Scolopendra subspinipes mutilans

PubMed Central

Cho, GyeYoon; Han, KyuChul; Yoon, JinYoung

2015-01-01

Objectives: Scolopendra subspinipes mutilans (S. subspinipes mutilans) is known as a traditional medicine and includes various amino acids, peptides and proteins. The amino acids in the pharmacopuncture extracted from S. subspinipes mutilans by using derivatization methods were analyzed quantitatively and qualitatively by using high performance liquid chromatography (HPLC) over a 12 month period to confirm its stability. Methods: Amino acids of pharmacopuncture extracted from S. subspinipes mutilans were derived by using O-phthaldialdehyde (OPA) & 9-fluorenyl methoxy carbonyl chloride (FMOC) reagent and were analyzed using HPLC. The amino acids were detected by using a diode array detector (DAD) and a fluorescence detector (FLD) to compare a mixed amino acid standard (STD) to the pharmacopuncture from centipedes. The stability tests on the pharmacopuncture from centipedes were done using HPLC for three conditions: a room temperature test chamber, an acceleration test chamber, and a cold test chamber. Results: The pharmacopuncture from centipedes was prepared by using the method of the Korean Pharmacopuncture Institute (KPI) and through quantitative analyses was shown to contain 9 amino acids of the 16 amino acids in the mixed amino acid STD. The amounts of the amino acids in the pharmacopuncture from centipedes were 34.37 ppm of aspartate, 123.72 ppm of arginine, 170.63 ppm of alanine, 59.55 ppm of leucine and 57 ppm of lysine. The relative standard deviation (RSD %) results for the pharmacopuncture from centipedes had a maximum value of 14.95% and minimum value of 1.795% on the room temperature test chamber, the acceleration test chamber and the cold test chamber stability tests. Conclusion: Stability tests on and quantitative and qualitative analyses of the amino acids in the pharmacopuncture extracted from centipedes by using derivatization methods were performed by using HPLC. Through research, we hope to determine the relationship between time and the concentrations of the amino acids in the pharmacopuncture extracted from centipedes. PMID:25830058

Stability Test and Quantitative and Qualitative Analyses of the Amino Acids in Pharmacopuncture Extracted from Scolopendra subspinipes mutilans.

PubMed

Cho, GyeYoon; Han, KyuChul; Yoon, JinYoung

2015-03-01

Scolopendra subspinipes mutilans (S. subspinipes mutilans) is known as a traditional medicine and includes various amino acids, peptides and proteins. The amino acids in the pharmacopuncture extracted from S. subspinipes mutilans by using derivatization methods were analyzed quantitatively and qualitatively by using high performance liquid chromatography (HPLC) over a 12 month period to confirm its stability. Amino acids of pharmacopuncture extracted from S. subspinipes mutilans were derived by using O-phthaldialdehyde (OPA) & 9-fluorenyl methoxy carbonyl chloride (FMOC) reagent and were analyzed using HPLC. The amino acids were detected by using a diode array detector (DAD) and a fluorescence detector (FLD) to compare a mixed amino acid standard (STD) to the pharmacopuncture from centipedes. The stability tests on the pharmacopuncture from centipedes were done using HPLC for three conditions: a room temperature test chamber, an acceleration test chamber, and a cold test chamber. The pharmacopuncture from centipedes was prepared by using the method of the Korean Pharmacopuncture Institute (KPI) and through quantitative analyses was shown to contain 9 amino acids of the 16 amino acids in the mixed amino acid STD. The amounts of the amino acids in the pharmacopuncture from centipedes were 34.37 ppm of aspartate, 123.72 ppm of arginine, 170.63 ppm of alanine, 59.55 ppm of leucine and 57 ppm of lysine. The relative standard deviation (RSD %) results for the pharmacopuncture from centipedes had a maximum value of 14.95% and minimum value of 1.795% on the room temperature test chamber, the acceleration test chamber and the cold test chamber stability tests. Stability tests on and quantitative and qualitative analyses of the amino acids in the pharmacopuncture extracted from centipedes by using derivatization methods were performed by using HPLC. Through research, we hope to determine the relationship between time and the concentrations of the amino acids in the pharmacopuncture extracted from centipedes.

Quantitative PCR high-resolution melting (qPCR-HRM) curve analysis, a new approach to simultaneously screen point mutations and large rearrangements: application to MLH1 germline mutations in Lynch syndrome.

PubMed

Rouleau, Etienne; Lefol, Cédrick; Bourdon, Violaine; Coulet, Florence; Noguchi, Tetsuro; Soubrier, Florent; Bièche, Ivan; Olschwang, Sylviane; Sobol, Hagay; Lidereau, Rosette

2009-06-01

Several techniques have been developed to screen mismatch repair (MMR) genes for deleterious mutations. Until now, two different techniques were required to screen for both point mutations and large rearrangements. For the first time, we propose a new approach, called "quantitative PCR (qPCR) high-resolution melting (HRM) curve analysis (qPCR-HRM)," which combines qPCR and HRM to obtain a rapid and cost-effective method suitable for testing a large series of samples. We designed PCR amplicons to scan the MLH1 gene using qPCR HRM. Seventy-six patients were fully scanned in replicate, including 14 wild-type patients and 62 patients with known mutations (57 point mutations and five rearrangements). To validate the detected mutations, we used sequencing and/or hybridization on a dedicated MLH1 array-comparative genomic hybridization (array-CGH). All point mutations and rearrangements detected by denaturing high-performance liquid chromatography (dHPLC)+multiplex ligation-dependent probe amplification (MLPA) were successfully detected by qPCR HRM. Three large rearrangements were characterized with the dedicated MLH1 array-CGH. One variant was detected with qPCR HRM in a wild-type patient and was located within the reverse primer. One variant was not detected with qPCR HRM or with dHPLC due to its proximity to a T-stretch. With qPCR HRM, prescreening for point mutations and large rearrangements are performed in one tube and in one step with a single machine, without the need for any automated sequencer in the prescreening process. In replicate, its reagent cost, sensitivity, and specificity are comparable to those of dHPLC+MLPA techniques. However, qPCR HRM outperformed the other techniques in terms of its rapidity and amount of data provided.

High-performance liquid chromatographic determination of histamine in biological samples: the cerebrospinal fluid challenge--a review.

PubMed

Wang, Zhaopin; Wu, Juanli; Wu, Shihua; Bao, Aimin

2013-04-24

Histamine, a neurotransmitter crucially involved in a number of basic physiological functions, undergoes changes in neuropsychiatric disorders. Detection of histamine in biological samples such as cerebrospinal fluid (CSF) is thus of clinical importance. The most commonly used method for measuring histamine levels is high performance liquid chromatography (HPLC). However, factors such as very low levels of histamine, the even lower CSF-histamine and CSF-histamine metabolite levels, especially in certain neuropsychiatric diseases, rapid formation of histamine metabolites, and other confounding elements during sample collection, make analysis of CSF-histamine and CSF-histamine metabolites a challenging task. Nonetheless, this challenge can be met, not only with respect to HPLC separation column, derivative reagent, and detector, but also in terms of optimizing the CSF sample collection. This review aims to provide a general insight into the quantitative analyses of histamine in biological samples, with an emphasis on HPLC instruments, methods, and hyphenated techniques, with the aim of promoting the development of an optimal and practical protocol for the determination of CSF-histamine and/or CSF-histamine metabolites. Copyright © 2013 Elsevier B.V. All rights reserved.

An optimized high-performance liquid chromatography (HPLC) method for benzoylmesaconine determination in Radix Aconiti Lateralis Preparata (Fuzi, aconite roots) and its products

PubMed Central

Xie, Ying; Zhou, Hua; Wong, Yuen Fan; Liu, Zhongqiu; Xu, Hongxi; Jiang, Zhihong; Liu, Liang

2008-01-01

Background Benzoylmesaconine (BMA) is the main Aconitum alkaloid in Radix Aconiti Lateralis Preparata (Fuzi, aconite roots) with potent pharmacological activities, such as analgesia and anti-inflammation. The present study developed a simple and reliable method using BMA as a marker compound for the quality control of processed aconite roots and their products. Methods After extraction, a high-performance liquid chromatography (HPLC) determination of BMA was conducted on a RP-C18 column by gradient elution with acetonitrile and aqueous phase, containing 0.1% phosphoric acid adjusted with triethylamine to pH 3.0. Results A distinct peak profile was obtained and separation of BMA was achieved. Method validation showed that the relative standard deviations (RSDs) of the precision of BMA in all intra-day and inter-day assays were less than 1.36%, and that the average recovery rate was 96.95%. Quantitative analysis of BMA showed that the content of BMA varied significantly in processed aconite roots and their products. Conclusion This HPLC method using BMA as a marker compound is applicable to the quality control of processed aconite roots and their products. PMID:18513409

Determination of fructooligosaccharides in burdock using HPLC and microwave-assisted extraction.

PubMed

Li, Jing; Liu, Xiaomei; Zhou, Bin; Zhao, Jing; Li, Shaoping

2013-06-19

The root of burdock ( Arctium lappa L.) is a commonly used vegetable in Asia. Fructooligosaccharides (FOS) are usually considered as its main bioactive components. Thus, quantitative analysis of these components is very important for the quality control of burdock. In this study, an HPLC-ELSD and microwave-assisted extraction method was developed for the simultaneous determination of seven FOS with degrees of polymerization (DP) between 3 and 9, as well as fructose, glucose, and sucrose in burdock from different regions. The separation was performed on a Waters XBridge Amide column (4.6 × 250 mm i.d., 3.5 μm) with gradient elution. All calibration curves for investigated analytes showed good linear regression (r > 0.9990). Their LODs and LOQs were lower than 3.63 and 24.82 μg/mL, respectively. The recoveries ranged from 99.2 to 102.6%. The developed method was successfully applied to determination of ten sugars in burdock from different locations of Asia. The results showed that the contents of FOS in different samples of burdock collected at appropriate times were similar, and the developed HPLC-ELSD with microwave-assisted extraction method is helpful to control the quality of burdock.

Determination of starting materials, intermediates, and subsidiary colors in the color additive Food Red No. 106 (Sulforhodamine B) using high-performance liquid chromatography.

PubMed

Tatebe, Chiye; Ohtsuki, Takashi; Fujita, Tsuyoshi; Nishiyama, Koji; Itoh, Sumio; Sugimoto, Naoki; Kubota, Hiroki; Tada, Atsuko; Sato, Kyoko; Akiyama, Hiroshi

2017-12-15

The main subsidiary color of structure in Food Red No. 106 (R106) was identified to be a desethyl derivative (R106-SubA). High-performance liquid chromatography (HPLC) was performed for the quantitative determination of benzaldehyde-2,4-disulfonic acid, N,N-diethyl-m-aminophenol, leuco acid, pyrone acid, R106-SubA, etc. in R106. An ammonium acetate solution (20mM) and acetonitrile:water (7:3) were used to stabilize the retention time of the HPLC analytes. The linearity of the calibration curves was in the range of 0.05-10μg/mL, with good correlation coefficients (R 2 >0.9983). The recoveries of impurities at levels 0.1%, 0.5% and 1% ranged from 94.2% to 106.6% with relative standard deviations of 0.1%-1.0%. While surveying commercial R106, the amounts obtained by area% determination were similar to those obtained by the calibration-curve determination. The area% determination by HPLC for the determinations of impurities in R106 is a simple and reliable method and can be applied in routine analysis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Short communication: Determination of withdrawal time for oxytetracycline in different types of goats for milk consumption.

PubMed

Attaie, Rahmat; Bsharat, Mohammed; Mora-Gutierrez, Adela; Woldesenbet, Sela

2015-07-01

Antibiotics are widely used in animal husbandry and the presence of antibiotics in milk is a health hazard. The objective of this study was to determine residual amounts of oxytetracycline in fresh, aged, and pasteurized milk of 3 breeds of goats using HPLC analysis. It was also essential to determine the safe withdrawal period of oxytetracycline in lactating goats. The quantitative results obtained using the HPLC system were compared with the tolerance limit of oxytetracycline in milk in the United States. Fifteen milking does, 5 Nubians, 5 Alpines, and 5 LaManchas were randomly selected from the milking herd at the International Goat Research Center at Prairie View A&M University. A simple sample preparation and isocratic HPLC method using ultraviolet detection was used for analysis of milk samples. The HPLC results indicated that the withdrawal period of oxytetracycline in treated Alpine does was 82h (7 milking), whereas for Nubian does the period was 58h (5 milking), and for LaManchas the period was 72h (6 milking) after drug administration. The overall withdrawal period for all the treated goats of 3 breeds was 72h. Although these results indicated that the depletion rate of this antibiotic was faster in goats than the reported data for cows, the 96-h withdrawal period that is currently used for lactating cows is still necessary for these 3 breeds of goats. Additionally, our results indicated that oxytetracycline is not stable in goat milk at refrigeration temperature or during pasteurization and will decrease significantly. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Quantitative Determination of Bioactive Constituents in Noni Juice by High-performance Liquid Chromatography with Electrospray Ionization Triple Quadrupole Mass Spectrometry.

PubMed

Yan, Yongqiu; Lu, Yu; Jiang, Shiping; Jiang, Yu; Tong, Yingpeng; Zuo, Limin; Yang, Jun; Gong, Feng; Zhang, Ling; Wang, Ping

2018-01-01

Noni juice has been extensively used as folk medicine for the treatment of arthritis, infections, analgesic, colds, cancers, and diabetes by Polynesians for many years. Due to the lack of standard scientific evaluation methods, various kinds of commercial Noni juice with different quality and price were available on the market. To establish a sensitive, reliable, and accurate high-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometry (HPLC-ESI-MS/MS) method for separation, identification, and simultaneous quantitative analysis of bioactive constituents in Noni juice. The analytes and eight batches of commercially available samples from different origins were separated and analyzed by the HPLC-ESI-MS/MS method on an Agilent ZORBAX SB-C 18 (150 mm × 4.6 mm i.d., 5 μm) column using a gradient elution of acetonitrile-methanol-0.05% glacial acetic acid in water (v/v) at a constant flow rate of 0.5 mL/min. Seven components were identification and all of the assay parameters were within the required limits. Components were within the correlation coefficient values ( R 2 ≥ 0.9993) at the concentration ranges tested. The precision of the assay method was <0.91% and the repeatability between 1.36% and 3.31%. The accuracy varied from 96.40% to 103.02% and the relative standard deviations of stability were <3.91%. Samples from the same origin showed similar content while different origins showed significant different result. The developed methods would provide a reliable basis and be useful in the establishment of a rational quality control standard of Noni juice. Separation, identification, and simultaneous quantitative analysis method of seven bioactive constituents in Noni juice is originally developed by high-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometryThe presented method was successfully applied to the quality control of eight batches of commercially available samples of Noni juiceThis method is simple, sensitive, reliable, accurate, and efficient method with strong specificity, good precision, and high recovery rate and provides a reliable basis for quality control of Noni juice. Abbreviations used: HPLC-ESI-MS/MS: High-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometry, LOD: Limit of detection, LOQ: Limit of quantitation, S/N: Signal-to-noise ratio, RSD: Relative standard deviations, DP: Declustering potential, CE: Collision energy, MRM: Multiple reaction monitoring, RT: Retention time.

Quantitative Determination of Bioactive Constituents in Noni Juice by High-performance Liquid Chromatography with Electrospray Ionization Triple Quadrupole Mass Spectrometry

PubMed Central

Yan, Yongqiu; Lu, Yu; Jiang, Shiping; Jiang, Yu; Tong, Yingpeng; Zuo, Limin; Yang, Jun; Gong, Feng; Zhang, Ling; Wang, Ping

2018-01-01

Background: Noni juice has been extensively used as folk medicine for the treatment of arthritis, infections, analgesic, colds, cancers, and diabetes by Polynesians for many years. Due to the lack of standard scientific evaluation methods, various kinds of commercial Noni juice with different quality and price were available on the market. Objective: To establish a sensitive, reliable, and accurate high-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometry (HPLC-ESI-MS/MS) method for separation, identification, and simultaneous quantitative analysis of bioactive constituents in Noni juice. Materials and Methods: The analytes and eight batches of commercially available samples from different origins were separated and analyzed by the HPLC-ESI-MS/MS method on an Agilent ZORBAX SB-C18 (150 mm × 4.6 mm i.d., 5 μm) column using a gradient elution of acetonitrile-methanol-0.05% glacial acetic acid in water (v/v) at a constant flow rate of 0.5 mL/min. Results: Seven components were identification and all of the assay parameters were within the required limits. Components were within the correlation coefficient values (R2 ≥ 0.9993) at the concentration ranges tested. The precision of the assay method was <0.91% and the repeatability between 1.36% and 3.31%. The accuracy varied from 96.40% to 103.02% and the relative standard deviations of stability were <3.91%. Samples from the same origin showed similar content while different origins showed significant different result. Conclusions: The developed methods would provide a reliable basis and be useful in the establishment of a rational quality control standard of Noni juice. SUMMARY Separation, identification, and simultaneous quantitative analysis method of seven bioactive constituents in Noni juice is originally developed by high-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometryThe presented method was successfully applied to the quality control of eight batches of commercially available samples of Noni juiceThis method is simple, sensitive, reliable, accurate, and efficient method with strong specificity, good precision, and high recovery rate and provides a reliable basis for quality control of Noni juice. Abbreviations used: HPLC-ESI-MS/MS: High-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometry, LOD: Limit of detection, LOQ: Limit of quantitation, S/N: Signal-to-noise ratio, RSD: Relative standard deviations, DP: Declustering potential, CE: Collision energy, MRM: Multiple reaction monitoring, RT: Retention time. PMID:29576704

[Analysis of Arsenic Compounds in Blood and Urine by HPLC-ICP-MS].

PubMed

Lin, L; Zhang, S J; Xu, W C; Luo, R X; Ma, D; Shen, M

2018-02-01

To establish an analysis method for the detection of 6 arsenic compounds [AsC, AsB, As（Ⅲ）, DMA, MMA and As（V）] in blood and urine by high-performance liquid chromatography-inductively coupled plasma-mass spectrometry （HPLC-ICP-MS）, and apply it to real cases. Triton was used to damage cells, and then EDTA·2Na·2H2O was used to complex arsenic compounds in cells, and sonication and protein deposition by acetonitrile were performed for sample pretreatment. With the mobile phase consisted of ammonium carbonate and ultrapure water, gradient elution was performed for obtaining the arsenic compounds in samples, which were analysed by ICP-MS with Hamilton PRP-X100 column. The limits of detection in blood were 1.66-10 ng/mL, while the lower limits of quantitation in blood ranged from 5 to 30 ng/mL. The limits of detection in urine were 0.5-10 ng/mL, while the lower limits of quantitation in urine were 5-30 ng/mL. The relative standard deviation of inter-day and intra-day precisions was less than 10%. This method had been successfully applied to 3 cases. This study has established an analysis method for detecting 6 common arsenic compounds in blood and urine, which can be used to detect the arsenic compounds in the blood and urine from arsenic poisoning cases as well as the patients under arsenic treatment. Copyright© by the Editorial Department of Journal of Forensic Medicine.

Structural Characterization of Cross-Linked Hemoglobins Developed as Potential Transfusion Substitutes

DTIC Science & Technology

1990-05-30

phase HPLC using an IBM Instruments Inc. model LC 9533 ternary liquid chromatograph attached to a model F9522 fixed UV module and a model F9523...acid analyses are done by separation and quantitation of phenylthiocarbamyl amino acid derivatives using a second IBM model LC 9533 ternary liquid...computer which controls the HPLC and an IBM Instruments Inc. model LC 9505 automatic sampler. The hemoglobin present in the effluent from large

Molecular assessment of the membrane menaquinones of irradiated micrococcus on disposable medical devices with high performance liquid chromatography (HPLC)

NASA Astrophysics Data System (ADS)

Ghojaie, M.

1993-10-01

The genus of micrococcus and its main species like; M. Roseus, M. Nishinomiyansis consist of upto 10% of microbial contamination of disposable medical devices. Chemical alteration of Menuquinones Mainly [MK-7-(H2), MK-8(H2),…] from some Irradiated species of the micrococcus at different doses (500 Gy to 25 kGy; the sterilization dose) are quantitatively evaluated by HPLC.

Biomass measurement of methane forming bacteria in environmental samples

NASA Technical Reports Server (NTRS)

Martz, R. F.; Sebacher, D. I.; White, D. C.

1983-01-01

Methane-forming bacteria contain unusual phytanylglycerol ether phospholipids which can be extracted from the bacteria in sediments and assayed quantitatively by high performance liquid chromatography (HPLC). In this procedure the lipids were extracted, the phospholipids recovered, hydrolyzed, purified by thin layer chromatography, derivatized and assayed by HPLC. Ether lipids were recovered quantitatively from Methanobacterium thermoautotrophicum and sediments at levels as low as 8 x 10(-14) moles. In freshwater and marine sediments the flux of methane to the atmosphere and the methane levels in the pore water reflects the recovery of the phytanyl glycerol ether lipid 'signature'. The proportion of the ether phospholipid to the total recoverable phospholipid was highest in anaerobic digester sewage sludge and deeper subsurface freshwater sediment horizons.

Quantitative measurement of indomethacin crystallinity in indomethacin-silica gel binary system using differential scanning calorimetry and X-ray powder diffractometry.

PubMed

Pan, Xiaohong; Julian, Thomas; Augsburger, Larry

2006-02-10

Differential scanning calorimetry (DSC) and X-ray powder diffractometry (XRPD) methods were developed for the quantitative analysis of the crystallinity of indomethacin (IMC) in IMC and silica gel (SG) binary system. The DSC calibration curve exhibited better linearity than that of XRPD. No phase transformation occurred in the IMC-SG mixtures during DSC measurement. The major sources of error in DSC measurements were inhomogeneous mixing and sampling. Analyzing the amount of IMC in the mixtures using high-performance liquid chromatography (HPLC) could reduce the sampling error. DSC demonstrated greater sensitivity and had less variation in measurement than XRPD in quantifying crystalline IMC in the IMC-SG binary system.

Optimization of Ultrasound-Assisted Extraction, HPLC and UHPLC-ESI-Q-TOF-MS/MS Analysis of Main Macamides and Macaenes from Maca (Cultivars of Lepidium meyenii Walp).

PubMed

Chen, Shu-Xiao; Li, Ke-Ke; Pubu, Duoji; Jiang, Si-Ping; Chen, Bin; Chen, Li-Rong; Yang, Zhen; Ma, Chao; Gong, Xiao-Jie

2017-12-10

Ultrasound-assisted extraction (UAE), using petroleum ether as the solvent, was systematically applied to extract main macamides and macaenes from Maca hypocotyls. Extraction yield was related with four variables, including ratio of solution to solid, extraction temperature, extraction time, and extraction power. On the basis of response surface methodology (RSM), the optimal conditions were determined to be the ratio of solution to solid as 10:1 (mL/g), the extraction temperature of 40 °C, the extraction time of 30 min, and the extraction power of 200 W. Based on the optimal extraction method of UAE, the total contents of ten main macamides and two main macaenes of Maca cultivated in twenty different areas of Tibet were analyzed by HPLC and UHPLC-ESI-Q-TOF-MS/MS. This study indicated that UAE was able to effectively extract macamides alkaloids from Maca hypocotyls. Quantitative analysis showed that geographical origins, not ecotypes, played a more important role on the accumulation of active macamides in Maca.

Quantitative analysis of iridoids, secoiridoids, xanthones and xanthone glycosides in Gentiana lutea L. roots by RP-HPLC and LC-MS.

PubMed

Aberham, Anita; Schwaiger, Stefan; Stuppner, Hermann; Ganzera, Markus

2007-11-05

The here described HPLC-method enables the determination of all major, currently known bioactive compounds in gentian roots. A separation of iridoids (loganic acid), secoiridoids (swertiamarin, gentiopicroside, amarogentin, sweroside), xanthones (gentisin, isogentisin) and two xanthone glycosides (gentiosides) was possible on RP-18 column material, using 0.025% aqueous TFA, acetonitrile and n-propanol as mobile phase. The method is sensitive (LOD

Quantitation of polycyclic aromatic hydrocarbons (PAH4) in cocoa and chocolate samples by an HPLC-FD method.

PubMed

Raters, Marion; Matissek, Reinhard

2014-11-05

As a consequence of the PAH4 (sum of four different polycyclic aromatic hydrocarbons, named benzo[a]anthracene, chrysene, benzo[b]fluoranthene, and benzo[a]pyrene) maximum levels permitted in cocoa beans and derived products as of 2013, an high-performance liquid chromatography with fluorescence detection method (HPLC-FD) was developed and adapted to the complex cocoa butter matrix to enable a simultaneous determination of PAH4. The resulting analysis method was subsequently successfully validated. This method meets the requirements of Regulation (EU) No. 836/2011 regarding analysis methods criteria for determining PAH4 and is hence most suitable for monitoring the observance of the maximum levels applicable under Regulation (EU) No. 835/2011. Within the scope of this work, a total of 218 samples of raw cocoa, cocoa masses, and cocoa butter from several sample years (1999-2012), of various origins and treatments, as well as cocoa and chocolate products were analyzed for the occurrence of PAH4. In summary, it is noted that the current PAH contamination level of cocoa products can be deemed very slight overall.

Performances of CN-columns for the analysis of γ-oryzanol and its p-coumarate and caffeate derivatives by normal phase HPLC and a validated method of quantitation.

PubMed

D'Ambrosio, Michele

2013-06-15

γ-Oryzanol is an important phytochemical used in pharmaceutical, alimentary and cosmetic preparations. The present article, for the first time, discloses the performances of NP-HPLC in separating γ-oryzanol components and develops a validated method for its routine quantification. The analysis is performed on a cyanopropyl bonded column using the hexane/MTBE gradient elution and UV detection at 325 nm. The method allows: the separation of steryl ferulate, p-coumarate and caffeate esters, the separation of cis- from trans-ferulate isomers, the splitting of steroid moieties into saturated and unsaturated at the side chain. The optimised method provides excellent linear response (R(2)=0.99997), high precision (RSD<1.0%) and satisfactory accuracy (R(∗)=70-86%). In conclusion, the established method presents the details of the procedure and the experimental conditions in order to achieve the required precision and instrumental accuracy. The method is fast and sensitive and it could be a suitable tool for quality assurance and determination of origin. Copyright © 2012 Elsevier Ltd. All rights reserved.

Physicochemical stability and biological activity of Withania somnifera extract under real-time and accelerated storage conditions.

PubMed

Patil, Dada; Gautam, Manish; Jadhav, Umesh; Mishra, Sanjay; Karupothula, Suresh; Gairola, Sunil; Jadhav, Suresh; Patwardhan, Bhushan

2010-03-01

Stability testing at preformulation stages is a crucial part of drug development. We studied physicochemical stability and biological activity of Withania somnifera (ashwagandha) dried root aqueous extract during six months real-time and under accelerated storage conditions. The characteristic constituents of ashwagandha roots include withanolides such as withaferin A and withanolide A. We modified and validated the HPLC-DAD method for quantitative measurement of withanolides and fingerprint analysis. The results suggest a significant decline in withaferin A and withanolide A content under real and accelerated conditions. The HPLC fingerprint analysis showed significant changes in some peaks during real and accelerated storage (> 20 %). We also observed incidences of clump formation and moisture sensitivity (> 10 %) under real-time and accelerated storage conditions. These changes were concurrent with a significant decline in immunomodulatory activity (p < 0.01) during the third month of the accelerated storage. Thus, adequate control of temperature and humidity is important for WSE containing formulations. This study may help in proposing suitable guidance for storage conditions and shelf life of ashwagandha formulations. (c) Georg Thieme Verlag KG Stuttgart . New York.

[Determination of markers from characteristic HPLC chromatogram of phenols in three official origins of Ephedrae Herba and quantitative analysis of four phenols].

PubMed

Zuo, Xue; Hong, Hao; Zang, Xin-yu; Xu, Feng; Shang, Ming-ying; Wang, Xuan; Cai, Shao-qing

2015-12-01

This study is to establish the characteristic HPLC chromatogram of phenols in Ephedrae Herba, from which to pick out the marker peaks, followed by the analysis of the regularity of their distribution and content in the herbaceous stems of Ephedra sinica, E. intermedia and E. equisetina. The HPLC-DAD method for the characteristic chromatogram as well as quantitative analysis was established. The separation was carried out on a YMC-Pack ODS-A column (4.6 mm x 250 mm, 5 µm), eluted with the mobile phases as 0.01% formic acid aqueous solution (A) and acetonitrile (B) in a linear gradient (0-10 min, 17% B; 10-25 min, 17%-19% B; 25- 33 min, 19%-48% B; 33-35 min, 48%-51% B; 35-44 min, 51% B). The flow rate was kept at 1.0 mL · min⁻¹. The column tem- perature was 40 °C, and the detection wavelength was set at 350 nm (0-16 min) and 330 nm (16-44 min). Forty-six batches of collected samples from three official origins of Ephedrae Herba were detected, whose liquid chromatograms proven to be helpful to the differentiation of different origins. With principal component analysis and the analysis of distribution of peak area, twelve key peaks from the chromatogram were discussed in details on their contributions to the characteristics and differences of three official origins of the herb: peak area of peak 10, 11, 12 were found out to be significantly higher in E. equisetina than in other two origins, whose sum (higher than 146 mAU in E. equisetina) was useful for the discrimination between E. equisetina and the other two origins; peak area of 1 and 4 were respectively higher in E. sinica and E. intermedia than in other official origins, indicating their important effect on the differen- tiation of corresponding origins; peak 8 and 9 were picked out as two characteristic common peaks in three official origins of the herb, whose peak area showed little difference among different origins; further, peak area of other key peaks in the chromatogram also showed some difference among three origins, which make contributions to the differentiation of origins as well. Then, four phenols as 2"-O-α- L-rhamnosyl-isovitexin (1), vitexin (2), pollenitin B (5) and herbacetin-7-O-β-D-glucoside (6) were quantitative analyzed with the above-mentioned method, with good linear relationship and accuracy (recoveries in a range of 97.8%-102.5%). The content of the four phenols were firstly reported in Ephedrae Herba from official origins, which were respectively trace-1.55 (1), trace-0.160 (2), trace-0.284 (5) and trace-0.620 (6) mg · g⁻¹ in all of the tested samples. In addition, the content of these phenols showed differences in three official origins, especially 1, whose content in E. sinica [(0.670 ± 0.88) mg ± g⁻¹] were significantly higher than in other two origins (lower than 0.16 mg ± g⁻¹ besides sample Ei-060630-2-2), and 6, whose average content in E. equisetina [(0.260 ± 0.039 2) mg · g⁻¹] were twice as high as in E. sinica [(0.120 ± 0.270) mg · g⁻¹] and E. intermedia [(0.136 ± 0.485) mg g⁻¹], indicating the important effects of the two constituents on the differentiation among three official origins of the herb. The method established for the characteristic HPLC chromatogram and quantitative analysis of phenols was simple and accurate, and the marker constituents selected may provide new guides for the discrimination of official origins as well as the improvement of quality criteria of EphedraeHerba.

Generation of accurate peptide retention data for targeted and data independent quantitative LC-MS analysis: Chromatographic lessons in proteomics.

PubMed

Krokhin, Oleg V; Spicer, Vic

2016-12-01

The emergence of data-independent quantitative LC-MS/MS analysis protocols further highlights the importance of high-quality reproducible chromatographic procedures. Knowing, controlling and being able to predict the effect of multiple factors that alter peptide RP-HPLC separation selectivity is critical for successful data collection for the construction of ion libraries. Proteomic researchers have often regarded RP-HPLC as a "black box", while vast amount of research on peptide separation is readily available. In addition to obvious parameters, such as the type of ion-pairing modifier, stationary phase and column temperature, we describe the "mysterious" effects of gradient slope, column size and flow rate on peptide separation selectivity. Retention time variations due to these parameters are governed by the linear solvent strength (LSS) theory on a peptide level by the value of its slope S in the basic LSS equation-a parameter that can be accurately predicted. Thus, the application of shallower gradients, higher flow rates, or smaller columns will each increases the relative retention of peptides with higher S-values (long species with multiple positively charged groups). Simultaneous changes to these parameters that each drive shifts in separation selectivity in the same direction should be avoided. The unification of terminology represents another pressing issue in this field of applied proteomics that should be addressed to facilitate further progress. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Assessment of powder blend uniformity: Comparison of real-time NIR blend monitoring with stratified sampling in combination with HPLC and at-line NIR Chemical Imaging.

PubMed

Bakri, Barbara; Weimer, Marco; Hauck, Gerrit; Reich, Gabriele

2015-11-01

Scope of the study was (1) to develop a lean quantitative calibration for real-time near-infrared (NIR) blend monitoring, which meets the requirements in early development of pharmaceutical products and (2) to compare the prediction performance of this approach with the results obtained from stratified sampling using a sample thief in combination with off-line high pressure liquid chromatography (HPLC) and at-line near-infrared chemical imaging (NIRCI). Tablets were manufactured from powder blends and analyzed with NIRCI and HPLC to verify the real-time results. The model formulation contained 25% w/w naproxen as a cohesive active pharmaceutical ingredient (API), microcrystalline cellulose and croscarmellose sodium as cohesive excipients and free-flowing mannitol. Five in-line NIR calibration approaches, all using the spectra from the end of the blending process as reference for PLS modeling, were compared in terms of selectivity, precision, prediction accuracy and robustness. High selectivity could be achieved with a "reduced" approach i.e. API and time saving approach (35% reduction of API amount) based on six concentration levels of the API with three levels realized by three independent powder blends and the additional levels obtained by simply increasing the API concentration in these blends. Accuracy and robustness were further improved by combining this calibration set with a second independent data set comprising different excipient concentrations and reflecting different environmental conditions. The combined calibration model was used to monitor the blending process of independent batches. For this model formulation the target concentration of the API could be achieved within 3 min indicating a short blending time. The in-line NIR approach was verified by stratified sampling HPLC and NIRCI results. All three methods revealed comparable results regarding blend end point determination. Differences in both mean API concentration and RSD values could be attributed to differences in effective sample size and thief sampling errors. This conclusion was supported by HPLC and NIRCI analysis of tablets manufactured from powder blends after different blending times. In summary, the study clearly demonstrates the ability to develop efficient and robust quantitative calibrations for real-time NIR powder blend monitoring with a reduced set of powder blends while avoiding any bias caused by physical sampling. Copyright © 2015 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lincoln, D.E.

Preliminary analysis of two populations of Artemisia tridentata compared leaf chemical and physiological characteristics which influence herbivores. The proportion of sixteen of the volatile compounds differed significantly between the two populations; however, total yield of volatiles did not. This initial survey established the reliability of the procedure to quantitatively monitor plant responses to CO/sub 2/ enrichment and suggests that test samples be restricted to a single population. Four sesquiterpene lactones have been selected for the experimental quantitative HPLC analysis; all peaks have been assigned identities and have demonstrated high degree of reproducibility. Growth of Artemisia under high and low lightmore » at three CO/sub 2/ levels demonstrated that this species also undergoes a ''dilution'' of the leaf carbon content and is useful as test species for herbivory response to CO/sub 2/ induced effects. The initial experiment also showed that high irradiance is a necessary growth condition. 10 refs.« less

A comparative uncertainty study of the calibration of macrolide antibiotic reference standards using quantitative nuclear magnetic resonance and mass balance methods.

PubMed

Liu, Shu-Yu; Hu, Chang-Qin

2007-10-17

This study introduces the general method of quantitative nuclear magnetic resonance (qNMR) for the calibration of reference standards of macrolide antibiotics. Several qNMR experimental conditions were optimized including delay, which is an important parameter of quantification. Three kinds of macrolide antibiotics were used to validate the accuracy of the qNMR method by comparison with the results obtained by the high performance liquid chromatography (HPLC) method. The purities of five common reference standards of macrolide antibiotics were measured by the 1H qNMR method and the mass balance method, respectively. The analysis results of the two methods were compared. The qNMR is quick and simple to use. In a new medicine research and development process, qNMR provides a new and reliable method for purity analysis of the reference standard.

Multi-wavelength spectrophotometric analysis for detection of xanthochromia in cerebrospinal fluid and accuracy for the diagnosis of subarachnoid hemorrhage.

PubMed

Smith, Andrew; Wu, Alan H B; Lynch, Kara L; Ko, Nerissa; Grenache, David G

2013-09-23

Cerebrospinal fluid (CSF) was examined for bilirubin, an important indicator for diagnosis of subarachnoid hemorrhage (SAH). A multi-wavelength (340, 415, and 460 nm) spectrophotometric assay was developed for the quantitative measurement of bilirubin in CSF, enabling the mathematical correction for absorbance of hemoglobin and proteins. Bilirubin and hemoglobin results were correlated to HPLC and a standard colorimetric assay, respectively. A subset of samples was sent for an absorbance reading at 450 nm following baseline correction. The multi-wavelength bilirubin assay was validated on 70 patients with confirmed SAH and 70 patients with neurologic symptoms who ruled out for SAH. The multi-wavelength spectrophometric assay demonstrated no interferences due to proteins (albumin) up to 30 g/l or oxyhemoglobin up to 260 mg/l. The assay limit of detection was 0.2 mg/l, linear to 20 mg/l, and CVs ranged from 1 to 6% at bilirubin concentrations of 0.84 and 2.1mg/l. The spectrophotometric assay correlated to HPLC and the colorimetric assay for bilirubin and hemoglobin, respectively. Results also correlated to the absorbance method (with removal of samples with high hemoglobin and proteins). The area under the ROC curve for diagnosis of SAH was 0.971 and 0.954 for the HPLC and spectrophotometric assay, respectively. At a cutoff of 0.2mg/l, the clinical specificity was 100% for both assays, and the clinical sensitivity was 94.3% and 88.6% for SAH for the HPLC and spectrophotometric asays, respectively. The multi-wavelength spectrophotometric assay is an objective alternative to visual inspection, HPLC, and absorbance for CSF bilirubin. Copyright © 2013 Elsevier B.V. All rights reserved.

High Incidence and Levels of Ochratoxin A in Wines Sourced from the United States.

PubMed

De Jesus, Christopher Lawrence; Bartley, Amanda; Welch, Aaron Z; Berry, John P

2017-12-21

Ochratoxin A (OTA) is one of the most prevalent mycotoxin contaminants of food crops. Among the agricultural products consequently contaminated by OTA is wine. In the present study, a sample of wines sourced from the United States was assessed for OTA. Wines were primarily analyzed by high-performance liquid chromatography with fluorescence detection (HPLC-FD) coupled to a liquid-liquid extraction (LLE) technique which was developed and validated as a simplified sample preparation approach. More than 85% of the wines evaluated were found to contain OTA, at levels above the limit-of-detection (LOD = 0.1 µg L -1 ), and 76% were above the limit-of-quantitation (LOQ = 0.3 µg L -1 ) for the LLE/HPLC-FD method. More than two-thirds of the wines above the LOQ were found to exceed 1 µg L -1 . Complementary analysis by HPLC coupled to tandem mass spectrometry (HPLC-MS/MS) confirmed OTA in 74% of the OTA-positive wines (i.e., >LOQ by HPLC-FD). Overall, both the occurrence and measured levels of OTA were generally high, specifically relative to previous assessments of OTA in wine, and two of the wines were above the only current (European Union) regulatory limit of two parts-per-billion (ppb, ~2 µg L -1 ). Possible trends with respect to geographical region and/or growing climate are noted. As the first assessment of U.S. wines in more than a decade, the overall high occurrence and levels of OTA in wine, and possible geographic and climatic trends, point to a need for regular surveillance of wines, as well as investigation of the relevant contributors to OTA occurrence toward mitigating contamination and exposure risks.

Isolation, characterization and HPLC quantification of compounds from Aquilegia fragrans Benth: Their in vitro antibacterial activities against bovine mastitis pathogens.

PubMed

Mushtaq, Saleem; Aga, Mushtaq A; Qazi, Parvaiz H; Ali, Md Niamat; Shah, Aabid Manzoor; Lone, Sajad Ahmad; Shah, Aiyatullah; Hussain, Aehtesham; Rasool, Faheem; Dar, Hafizullah; Shah, Zeeshan Hamid; Lone, Shabir H

2016-02-03

The underground parts of Aquilegia fragrans are traditionally used for the treatment of wounds and various inflammatory diseases like bovine mastitis. However, there are no reports on the phytochemical characterization and antibacterial studies of A. fragrans. To isolate compounds from the methanol extract of the underground parts of A. fragrans and determine their antibacterial activity against the pathogens of bovine mastitis. The study was undertaken in order to scientifically validate the traditional use of A. fragrans. Five compounds were isolated from the methanol extract of the underground parts of A. fragrans using silica gel column chromatography. Structural elucidation of the isolated compounds was done using spectral data analysis and comparison with literature. High performance liquid chromatography (HPLC) was used for the qualitative and quantitative determination of isolated compounds in the crude methanol extract. The methanol extract and isolated compounds were evaluated for antibacterial activities against mastitis pathogens using broth micro-dilution technique. The five isolated compounds were identified as (1) 2, 4-dihydroxyphenylacetic acid methyl ester (2) β-sitosterol (3) Aquilegiolide (4) Glochidionolactone-A and (5) Magnoflorine. A quick and sensitive HPLC method was developed for the first time for qualitative and quantitative determination of four isolated marker compounds from A. fragrans. The crude methanol extract and compound 5 exhibited weak antibacterial activities that varied between the bacterial species (MIC=500-3000 µg/ml). The above results show that the crude methanol extract and isolated compounds from A. fragrans exhibit weak antibacterial activities. Further phytochemical and pharmacological studies are required for proper scientific validation of the folk use of this plant species in the treatment of various inflammatory diseases like bovine mastitis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Simultaneous quantification of delta-9-THC, THC-acid A, CBN and CBD in seized drugs using HPLC-DAD.

PubMed

Ambach, Lars; Penitschka, Franziska; Broillet, Alain; König, Stefan; Weinmann, Wolfgang; Bernhard, Werner

2014-10-01

An HPLC-DAD method for the quantitative analysis of Δ(9)-tetrahydrocannabinol (THC), Δ(9)-tetrahydrocannabinolic acid-A (THCA-A), cannabidiol (CBD), and cannabinol (CBN) in confiscated cannabis products has been developed, fully validated and applied to analyse seized cannabis products. For determination of the THC content of plant material, this method combines quantitation of THCA-A, which is the inactive precursor of THC, and free THC. Plant material was dried, homogenized and extracted with methanol by ultrasonication. Chromatographic separation was achieved with a Waters Alliance 2695 HPLC equipped with a Merck LiChrospher 60 RP-Select B (5μm) precolumn and a Merck LiChroCart 125-4 LiChrospher 60 RP-Select B (5μm) analytical column. Analytes were detected and quantified using a Waters 2996 photo diode array detector. This method has been accepted by the public authorities of Switzerland (Bundesamt für Gesundheit, Federal Office of Public Health), and has been used to analyse 9092 samples since 2000. Since no thermal decarboxylation of THCA-A occurs, the method is highly reproducible for different cannabis materials. Two calibration ranges are used, a lower one for THC, CBN and CBD, and a higher one for THCA-A, due to its dominant presence in fresh plant material. As provider of the Swiss proficiency test, the robustness of this method has been tested over several years, and homogeneity tests even in the low calibration range (1%) show high precision (RSD≤4.3%, except CBD) and accuracy (bias≤4.1%, except CBN). Copyright © 2014. Published by Elsevier Ireland Ltd.

Characterizing a Full Spectrum of Physico-Chemical Properties of Ginsenosides Rb1 and Rg1 to Be Proposed as Standard Reference Materials

PubMed Central

Kim, Il-Woung; Hong, Hee-Do; Choi, Sang Yoon; Hwang, Da-Hye; Her, Youl; Kim, Si-Kwan

2011-01-01

Good manufacturing practice (GMP)-based quality control is an integral component of the common technical document, a formal documentation process for applying a marketing authorization holder to those countries where ginseng is classified as a medicine. In addition, authentication of the physico-chemical properties of ginsenoside reference materials, and qualitative and quantitative batch analytical data based on validated analytical procedures are prerequisites for certifying GMP. Therefore, the aim of this study was to propose an authentication process for isolated ginsenosides Rb1 and Rg1 as reference materials (RM) and for these compounds to be designated as RMs for ginseng preparations throughout the world. Ginsenoside Rb1 and Rg1 were isolated by Diaion HP-20 adsorption chromatography, silica gel flash chromatography, recrystallization, and preparative HPLC. HPLC fractions corresponding to those two ginsenosides were recrystallized in appropriate solvents for the analysis of physico-chemical properties. Documentation of the isolated ginsenosides was made according to the method proposed by Gaedcke and Steinhoff. The ginsenosides were subjected to analyses of their general characteristics, identification, purity, content quantitation, and mass balance tests. The isolated ginsenosides were proven to be a single compound when analyzed by three different HPLC systems. Also, the water content was found to be 0.940% for Rb1 and 0.485% for Rg1, meaning that the net mass balance for ginsenoside Rb1 and Rg1 were 99.060% and 99.515%, respectively. From these results, we could assess and propose a full spectrum of physicochemical properties for the ginsenosides Rb1 and Rg1 as standard reference materials for GMP-based quality control. PMID:23717096

Reconstitution of the flavor signature of Dornfelder red wine on the basis of the natural concentrations of its key aroma and taste compounds.

PubMed

Frank, Stephanie; Wollmann, Nadine; Schieberle, Peter; Hofmann, Thomas

2011-08-24

By application of aroma extract dilution analysis (AEDA) on the volatile fraction isolated from a Dornfelder red wine, 31 odor-active compounds were identified by means of HRGC-MS and comparison with reference compounds. A total of 27 odorants, judged with high FD factors by means of AEDA, was quantitated by means of stable isotope dilution assays, and acetaldehyde was determined enzymatically. In addition, 36 taste-active compounds were analyzed by means of HPLC-UV, HPLC-MS/MS, and ion chromatography. The quantitative data obtained for the identified aroma and taste compounds enabled for the first time the reconstruction of the overall flavor of the red wine. Sensory evaluation of both the aroma and taste profiles of the authentic red wine and the recombinate revealed that Dornfelder red wine was closely mimicked. Moreover, it was demonstrated that the high molecular weight fraction of red wine is essential for its astringent taste impression. By comparison of the overall odor of the aroma recombinate in ethanol with that of the total flavor recombinate containing all tastants, it was shown for the first time that the nonvolatile tastants had a strong influence on the intensity of certain aroma qualities.

Quantitative analysis of the eight major compounds in the Samsoeum using a high-performance liquid chromatography coupled with diode array detection and electrospray ionization mass spectrometer

PubMed Central

Weon, Jin Bae; Yang, Hye Jin; Lee, Bohyoung; Ma, Jin Yeul; Ma, Choong Je

2015-01-01

Background: Samsoeum was traditionally used for treatment of a respiratory disease. Objective: The simultaneous determination of eight major compounds, ginsenoside Rg3, caffeic acid, puerarin, costunolide, hesperidin, naringin, glycyrrhizin, and 6-gingerol in the Samsoeum using a high-performance liquid chromatography (HPLC) coupled with diode array detection (DAD) and an electrospray ionization mass spectrometer was developed for an accurate and reliable quality assessment. Materials and Methods: Eight compounds were qualitative identified based on their mass spectra and by comparing with standard compounds and quantitative analyzed by HPLC-DAD. Separation of eight compounds was carried out on a LUNA C18 column (S-5 μm, 4.6 mm i.d. ×250 mm) with gradient elution composed of acetonitrile and 0.1% trifluoroacetic acid. Results: The data showed good linearity (R2 > 0.9996). The limits of detection and the limits of quantification were <0.53 μg and 1.62 μg, respectively. Inter- and Intra-day precisions (expressed as relative standard deviation values) were within 1.94% and 1.91%, respectively. The recovery of the method was in the range of 94.24–107.90%. Conclusion: The established method is effective and could be applied to quality control of Samsoeum. PMID:25829771

Analysis of organic acids and acylglycines for the diagnosis of related inborn errors of metabolism by GC- and HPLC-MS.

PubMed

la Marca, Giancarlo; Rizzo, Cristiano

2011-01-01

The analysis of organic acids in urine is commonly included in routine procedures for detecting many inborn errors of metabolism. Many analytical methods allow for both qualitative and quantitative determination of organic acids, mainly in urine but also in plasma, serum, whole blood, amniotic fluid, and cerebrospinal fluid. Liquid-liquid extraction and solid-phase extraction using anion exchange or silica columns are commonly employed approaches for sample treatment. Before analysis can be carried out using gas chromatography-mass spectrometry, organic acids must be converted into more thermally stable, volatile, and chemically inert forms, mainly trimethylsilyl ethers, esters, or methyl esters.

Simultaneous quantitation of chloroquine and primaquine by UPLC-DAD and comparison with a HPLC-DAD method.

PubMed

Miranda, Tiago A; Silva, Pedro H R; Pianetti, Gerson A; César, Isabela C

2015-01-28

Chloroquine and primaquine are the first-line treatment recommended by World Health Organization for malaria caused by Plasmodium vivax. Since the problem of counterfeit or substandard anti-malarials is well established all over the world, the development of rapid and reliable methods for quality control analysis of these drugs is essential. Thus, the aim of this study was to develop and validate a novel UPLC-DAD method for simultaneously quantifying chloroquine and primaquine in tablet formulations. The UPLC separation was carried out using a Hypersil C18 column (50 × 2.1 mm id; 1.9 μm particle size) and a mobile phase composed of acetonitrile (A) and 0.1% aqueous triethylamine, pH 3.0 adjusted with phosphoric acid (B), at a flow rate 0.6 mL/min. Gradient elution was employed. UV detection was performed at 260 nm. UPLC method was fully validated and the results were compared to a conventional HPLC-DAD method for the analysis of chloroquine and primaquine in tablet formulations. UPLC method was shown to be linear (r2 > 0.99), precise (CV < 2.0%), accurate (recovery rates from 98.11 to 99.83%), specific, and robust. No significant differences were observed between the chloroquine and primaquine contents obtained by UPLC and HPLC methods. However, UPLC method promoted faster analyses, better chromatographic performance and lower solvent consumption. The developed UPLC method was shown to be a rapid and suitable technique to quantify chloroquine and primaquine in pharmaceutical preparations and may be successfully employed for quality control analysis.

Multivariate analysis of organic acids in fermented food from reversed-phase high-performance liquid chromatography data.

PubMed

Mortera, Pablo; Zuljan, Federico A; Magni, Christian; Bortolato, Santiago A; Alarcón, Sergio H

2018-02-01

Multivariate calibration coupled to RP-HPLC with diode array detection (HPLC-DAD) was applied to the identification and the quantitative evaluation of the short chain organic acids (malic, oxalic, formic, lactic, acetic, citric, pyruvic, succinic, tartaric, propionic and α-cetoglutaric) in fermented food. The goal of the present study was to get the successful resolution of a system in the combined occurrence of strongly coeluting peaks, of distortions in the time sensors among chromatograms, and of the presence of unexpected compounds not included in the calibration step. Second-order HPLC-DAD data matrices were obtained in a short time (10min) on a C18 column with a chromatographic system operating in isocratic mode (mobile phase was 20mmolL -1 phosphate buffer at pH 2.20) and a flow-rate of 1.0mLmin -1 at room temperature. Parallel factor analysis (PARAFAC) and unfolded partial least-squares combined with residual bilinearization (U-PLS/RBL) were the second-order calibration algorithms select for data processing. The performance of the analytical parameters was good with an outstanding limit of detection (LODs) for acids ranging from 0.15 to 10.0mmolL -1 in the validation samples. The improved method was applied to the analysis of many dairy products (yoghurt, cultured milk and cheese) and wine. The method was shown as an effective means for determining and following acid contents in fermented food and was characterized by reducibility with simple, high resolution and rapid procedure without derivatization of analytes. Copyright © 2017 Elsevier B.V. All rights reserved.

Determination of apalcillin and its metabolites in human body fluids by high-pressure liquid chromatography.

PubMed Central

Borner, K; Lode, H; Elvers, A

1982-01-01

We describe two methods for the quantitative analysis of apalcillin and its metabolites in serum and urine by reverse-phase high-pressure liquid chromatography (HPLC), a fast isocratic method for the parent drug, and a gradient method that allows the simultaneous assay of two metabolites. Serum was deproteinized with acetonitrile, and urine was diluted with buffer solution. The detection limit was about 0.5 micrograms/ml at a detection wavelength of 254 nm and 1.5 micrograms/ml at 310 nm. Within-batch precision (coefficient of variation) varied from 10.2 to 1.1% for concentrations of 7.8 and 185.3 micrograms/ml of serum, respectively. Recovery rates of 95.1 and 97.7% were found in spiked sera. Results obtained by HPLC correlated well with those from a standard microbiological assay (agar diffusion test); the resulting bivariate regression equation for serum was y-bioassay = 2.5 micrograms/ml + 0.992 X xHPLC, and that for urine was ybioassay = 12.0 micrograms/ml + 1.009 X xHPLC. At a detection wavelength of 315 nm, no interferences were observed in 10 healthy volunteers. Healthy subjects who were given 2 g of apalcillin intravenously excreted 18% of the parent drug within 24 h in the urine. Two inactive compounds were furthermore identified in urine as the isomeric forms of the penicilloic acids. Their excretion within 24 h amounted to 6.9 and 11.2% of the dose. PMID:6818901

Mycotoxin analysis: an update.

PubMed

Krska, Rudolf; Schubert-Ullrich, Patricia; Molinelli, Alexandra; Sulyok, Michael; MacDonald, Susan; Crews, Colin

2008-02-01

Mycotoxin contamination of cereals and related products used for feed can cause intoxication, especially in farm animals. Therefore, efficient analytical tools for the qualitative and quantitative analysis of toxic fungal metabolites in feed are required. Current methods usually include an extraction step, a clean-up step to reduce or eliminate unwanted co-extracted matrix components and a separation step with suitably specific detection ability. Quantitative methods of analysis for most mycotoxins use immunoaffinity clean-up with high-performance liquid chromatography (HPLC) separation in combination with UV and/or fluorescence detection. Screening of samples contaminated with mycotoxins is frequently performed by thin layer chromatography (TLC), which yields qualitative or semi-quantitative results. Nowadays, enzyme-linked immunosorbent assays (ELISA) are often used for rapid screening. A number of promising methods, such as fluorescence polarization immunoassays, dipsticks, and even newer methods such as biosensors and non-invasive techniques based on infrared spectroscopy, have shown great potential for mycotoxin analysis. Currently, there is a strong trend towards the use of multi-mycotoxin methods for the simultaneous analysis of several of the important Fusarium mycotoxins, which is best achieved by LC-MS/MS (liquid chromatography with tandem mass spectrometry). This review focuses on recent developments in the determination of mycotoxins with a special emphasis on LC-MS/MS and emerging rapid methods.

Analysis of sweet diterpene glycosides from Stevia rebaudiana: improved HPLC method.

PubMed

Kolb, N; Herrera, J L; Ferreyra, D J; Uliana, R F

2001-10-01

An improved analytical method was developed which may be applied to quality control of stevioside and rebaudioside A contents in dried leaves of Stevia rebaudiana before processing; in a selective sampling program searching for plants of higher yield in diterpene glycosides content; or when a large number of samples are sent to the laboratory for analysis. The procedure developed involves two steps: solvent extraction followed by an isocratic HPLC analysis. The sample, 1 g of dried leaves of S. rebaudiana, is ground and solvent-extracted with EtOH 70% (w/w) in Erlenmeyer flasks by shaking for 30 min in a 70 degrees C water bath. After the extract was cooled, it was filtered and analyzed by HPLC using an NH(2) column (250 x 4.6 mm) and a mixture of acetonitrile/water (80:20, v/v) as mobile phase, pH 5 adjusted with acetic acid. The detection was in the UV range at 210 nm (0.04 AUFS). Quantitation was performed by means of an external standard calibration curve for each analyte which had been obtained from standard solutions of pure stevioside and rebaudioside A. Working under these conditions there were no observed interference effects. The method saves time in sample preparation, and reduces sample handling and chromatographic analysis time, while having little loss of precision [coefficient of variation (CV%) between 1.8% and 3.0%] and recovery [between 98.5% and 100.5%]. The method was applied to 30 samples of S. rebaudiana from Misiones (Northeastern Argentina), and the stevioside content found ranged between 3.78 and 9.75% (weight) whereas Rebaudioside A content ranged between 1.62 and 7.27% (weight).

Sensitive determination of thiols in wine samples by a stable isotope-coded derivatization reagent d0/d4-acridone-10-ethyl-N-maleimide coupled with high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry analysis.

PubMed

Lv, Zhengxian; You, Jinmao; Lu, Shuaimin; Sun, Weidi; Ji, Zhongyin; Sun, Zhiwei; Song, Cuihua; Chen, Guang; Li, Guoliang; Hu, Na; Zhou, Wu; Suo, Yourui

2017-03-31

As the key aroma compounds, varietal thiols are the crucial odorants responsible for the flavor of wines. Quantitative analysis of thiols can provide crucial information for the aroma profiles of different wine styles. In this study, a rapid and sensitive method for the simultaneous determination of six thiols in wine using d 0 /d 4 -acridone-10-ethyl-N-maleimide (d 0 /d 4 -AENM) as stable isotope-coded derivatization reagent (SICD) by high performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS) has been developed. Quantification of thiols was performed by using d 4 -AENM labeled thiols as the internal standards (IS), followed by stable isotope dilution HPLC-ESI-MS/MS analysis. The AENM derivatization combined with multiple reactions monitoring (MRM) not only allowed trace analysis of thiols due to the extremely high sensitivity, but also efficiently corrected the matrix effects during HPLC-MS/MS and the fluctuation in MS/MS signal intensity due to instrument. The obtained internal standard calibration curves for six thiols were linear over the range of 25-10,000pmol/L (R 2 ≥0.9961). Detection limits (LODs) for most of analytes were below 6.3pmol/L. The proposed method was successfully applied for the simultaneous determination of six kinds of thiols in wine samples with precisions ≤3.5% and recoveries ≥78.1%. In conclusion, the developed method is expected to be a promising tool for detection of trace thiols in wine and also in other complex matrix. Copyright © 2017 Elsevier B.V. All rights reserved.

The evaluation of different sorbents for the preconcentration of phenoxyacetic acid herbicides and their metabolites from soils.

PubMed

Moret, Sònia; Sánchez, Juan M; Salvadó, Victòria; Hidalgo, Manuela

2005-12-16

A procedure using alkaline extraction, solid-phase extraction (SPE) and HPLC is developed to analyze the polar herbicides 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-methylphenoxyacetic acid (MCPA) together with their main metabolites in soils. An ion-pairing HPLC method is used for the determination as it permits the baseline separation of these highly polar herbicides and their main metabolites. The use of a highly cross-linked polystyrene-divinylbenzene sorbent (PS-DVB) gives the best results for the analysis of these compounds. This sorbent allows the direct preconcentration of the analytes at the high pH values obtained after quantitative alkaline extraction of the herbicides from soil samples. Different parameters are evaluated for the SPE preconcentration step. The high polarity of the main analytes of interest (2,4-D and MCPA) makes it necessary to work at low flow rates (< or =0.5 mL min(-1)) in order for these compounds to be retained by the PS-DVB sorbent. A two stage desorption from the SPE sorbent is required to obtain the analytes in solvents that are appropriate for HPLC determination. A first desorption with a 50:50 methanol:water mixture elutes the most polar analytes (2,4-D, MCPA and 2CP). The second elution step with methanol permits the analysis of the other phenol derivatives. The humic and fulvic substances present in the soil are not efficiently retained by PS-DVB sorbents at alkaline pH's and so do not interfere in the analysis. This method has been successfully applied in the analysis of soil samples from a golf course treated with a commercial product containing esters of 2,4-D and MCPA as the active components.

Analytical Characterization of an Oil-in-Water Adjuvant Emulsion.

PubMed

Sun, Jenny; Remmele, Richard L; Sanyal, Gautam

2017-07-01

Adjuvants are typically used in subunit vaccine formulations to enhance immune responses elicited by individual antigens. Physical chemical characterization of novel adjuvants is an important step in ensuring their effective use in vaccine formulations. This paper reports application of a panel of quantitative assays developed to analyze and characterize an oil-in-water adjuvant emulsion, which contains glucopyranosyl lipid A (GLA) and is a squalene-based emulsion. GLA is a fully synthetic analogue of monophosphoryl lipid A, which is a Toll-like receptor type 4 agonist and an FDA-approved adjuvant. The GLA-stable emulsion (GLA-SE) is currently being used for a respiratory syncytial virus vaccine in a phase 2 clinical trial. GLA was quantitated using reverse-phased high-performance liquid chromatography (RP-HPLC) coupled to a mass spectrometric detector, achieving higher assay sensitivity than the charged aerosol detection routinely used. Quantitation of the excipients of GLA-SE, including squalene, egg phosphatidyl choline, and Poloxamer 188, was achieved using a simple and rapid RP-HPLC method with evaporative light scattering detection, eliminating chemical derivatization typically required for these chromophore-lacking compounds. DL-α-tocopherol, the antioxidant of the GLA-SE, was quantitated using a RP-HPLC method with conventional UV detection. The experimental results compared well with values expected for these compounds based on targeted composition of the adjuvant. The assays were applied to identify degradation of individual components in a GLA-SE sample that degraded into distinct aqueous and oil phases. The methods developed and reported here are effective tools in monitoring physicochemical integrity of the adjuvant, as well as in formulation studies.

Chemical compositions, chromatographic fingerprints and antioxidant activities of Andrographis Herba.

PubMed

Zhao, Yang; Kao, Chun-Pin; Wu, Kun-Chang; Liao, Chi-Ren; Ho, Yu-Ling; Chang, Yuan-Shiun

2014-11-10

This paper describes the development of an HPLC-UV-MS method for quantitative determination of andrographolide and dehydroandrographolide in Andrographis Herba and establishment of its chromatographic fingerprint. The method was validated for linearity, limit of detection and quantification, inter- and intra-day precisions, repeatability, stability and recovery. All the validation results of quantitative determination and fingerprinting methods were satisfactory. The developed method was then applied to assay the contents of andrographolide and dehydroandrographolide and to acquire the fingerprints of all the collected Andrographis Herba samples. Furthermore, similarity analysis and principal component analysis were used to reveal the similarities and differences between the samples on the basis of the characteristic peaks. More importantly, the DPPH free radical-scavenging and ferric reducing capacities of the Andrographis Herba samples were assayed. By bivariate correlation analysis, we found that six compounds are positively correlated to DPPH free radical scavenging and ferric reducing capacities, and four compounds are negatively correlated to DPPH free radical scavenging and ferric reducing capacities.

Rapid Analysis of Bisphenol A and Its Analogues in Food Packaging Products by Paper Spray Ionization Mass Spectrometry.

PubMed

Chen, Shuo; Chang, Quanying; Yin, Kai; He, Qunying; Deng, Yongxiu; Chen, Bo; Liu, Chengbin; Wang, Ying; Wang, Liping

2017-06-14

In this study, a paper spray ionization mass spectrometric (PS-MS) method was developed for the rapid in situ screening and simultaneous quantitative analysis of bisphenol A and its analogues, i.e., bisphenol S, bisphenol F, and bisphenol AF, in food packaging products. At the optimal PS-MS conditions, the calibration curves of bisphenols in the range of 1-100 μg/mL were linear. The correlation coefficients were higher than 0.998, and the LODs of the target compounds were 0.1-0.3 μg/mL. After a simple treatment by dichloromethane on the surface, the samples were analyzed by PS-MS in situ for rapid screening without a traditional sample pretreatment procedure, such as powdering, extraction, and enrichment steps. The analytical time of the PS-MS method was less than 1 min. In comparison with conventional HPLC-MS/MS, it was demonstrated that PS-MS was a more effective high-throughput screening and quantitative analysis method.

Analysis and Quantitation of Glycated Hemoglobin by Matrix Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry

NASA Astrophysics Data System (ADS)

Hattan, Stephen J.; Parker, Kenneth C.; Vestal, Marvin L.; Yang, Jane Y.; Herold, David A.; Duncan, Mark W.

2016-03-01

Measurement of glycated hemoglobin is widely used for the diagnosis and monitoring of diabetes mellitus. Matrix assisted laser desorption/ionization (MALDI) time of flight (TOF) mass spectrometry (MS) analysis of patient samples is used to demonstrate a method for quantitation of total glycation on the β-subunit of hemoglobin. The approach is accurate and calibrated with commercially available reference materials. Measurements were linear (R2 > 0.99) across the clinically relevant range of 4% to 20% glycation with coefficients of variation of ≤ 2.5%. Additional and independent measurements of glycation of the α-subunit of hemoglobin are used to validate β-subunit glycation measurements and distinguish hemoglobin variants. Results obtained by MALDI-TOF MS were compared with those obtained in a clinical laboratory using validated HPLC methodology. MALDI-TOF MS sample preparation was minimal and analysis times were rapid making the method an attractive alternative to methodologies currently in practice.

[Improvement of 2-mercaptoimidazoline analysis in rubber products containing chlorine].

PubMed

Kaneko, Reiko; Haneishi, Nahoko; Kawamura, Yoko

2012-01-01

An improved analysis method for 2-mercaptoimidazoline in rubber products containing chlorine was developed. 2-Mercaptoimidazoline (20 µg/mL) is detected by means of TLC with two developing solvents in the official method. But, this method is not quantitative. Instead, we employed HPLC using water-methanol (9 : 1) as the mobile phase. This procedure decreased interfering peaks, and the quantitation limit was 2 µg/mL of standard solution. 2-Mercaptoimidazoline was confirmed by GC-MS (5 µg/mL) and LC/MS (1 µg/mL) in the scan mode. For preparation of test solution, a soaking extraction method, in which 20 mL of methanol was added to the sample and allowed to stand overnight at about 40°C, was used. This gave similar values to the Soxhlet extraction method (official method) and was more convenient. The results indicate that our procedure is suitable for analysis of 2-mercaptoimidazoline. When 2-mercaptoimidazoline is detected, it is confirmed by either GC/MS or LC/MS.

Quantitative estimation of gymnemagenin in Gymnema sylvestre extract and its marketed formulations using the HPLC-ESI-MS/MS method.

PubMed

Kamble, Bhagyashree; Gupta, Ankur; Patil, Dada; Janrao, Shirish; Khatal, Laxman; Duraiswamy, B

2013-02-01

Gymnema sylvestre, with gymnemic acids as active pharmacological constituents, is a popular ayurvedic herb and has been used to treat diabetes, as a remedy for cough and as a diuretic. However, very few analytical methods are available for quality control of this herb and its marketed formulations. To develop and validate a new, rapid, sensitive and selective HPLC-ESI (electrospray ionisation)-MS/MS method for quantitative estimation of gymnemagenin in G. sylvestre and its marketed formulations. HPLC-ESI-MS/MS method using a multiple reactions monitoring mode was used for quantitation of gymnemagenin. Separation was carried out on a Luna C-18 column using gradient elution of water and methanol (with 0.1% formic acid and 0.3% ammonia). The developed method was validated as per International Conference on Harmonisation Guideline ICH-Q2B and found to be accurate, precise and linear over a relatively wide range of concentrations (5.280-305.920 ng/mL). Gymnemagenin contents were found from 0.056 ± 0.002 to 4.77 ± 0.59% w/w in G. sylvestre and its marketed formulations. The method established is simple, rapid, with high sample throughput, and can be used as a tool for quality control of G. sylvestre and its formulations. Copyright © 2012 John Wiley & Sons, Ltd.

[Quantitative analysis of nucleosides in four Cordyceps genus by HPLC].

PubMed

Qian, Zheng-Ming; Li, Wen-Qing; Wang, Chuan-Xi; Zhou, Miao-Xia; Sun, Min-Tian; Gao, Hao; Li, Wen-Jia

2016-07-01

To compare the main nucleosides in Cordyceps genus herbs (C. sinensis, C. millitaris, Hirsutella sinensis and C. sobolifera), an HPLC method for simultaneous determination of uridine, inosine, guanosine, adenosine and cordycepine in Cordyceps genus herbs was developed. The sample was extracted with 0.5% phosphoric acid solution to prepare test solution. The separation was performed on a Zorbax SB-Aq (4.6 mm×150 mm, 5 μm) column with gradient elution by 0.04 mol•L⁻¹ potassium dihydrogen phosphate solution and acetonitrile, column temperature 30 ℃,flow rate 0.8 mL•min⁻¹,and detection wavelength 260 nm. The content of nucleosides in four Cordyceps genus herbs was evaluated by fingerprint analysis and hierarchical cluster analysis (HCA). The calibration curves of five nucleosides showed good linear regression (r>0.99) and the average recoveries were between 95.0% and 105.0%. The contents of the five nucleosides in the four Cordyceps genus herbs were different and could be obviously distinguished by HCA. The fingerprint analysis result showed that the similarity between C. sinensis and the others was less than 0.9. The method was accurate and reliable, which can be used for quality control of Cordyceps genus herbs. Copyright© by the Chinese Pharmaceutical Association.

Quantitation of lysergic acid diethylamide in urine using atmospheric pressure matrix-assisted laser desorption/ionization ion trap mass spectrometry.

PubMed

Cui, Meng; McCooeye, Margaret A; Fraser, Catharine; Mester, Zoltán

2004-12-01

A quantitative method was developed for analysis of lysergic acid diethylamide (LSD) in urine using atmospheric pressure matrix-assisted laser desorption/ionization ion trap mass spectrometry (AP MALDI-ITMS). Following solid-phase extraction of LSD from urine samples, extracts were analyzed by AP MALDI-ITMS. The identity of LSD was confirmed by fragmentation of the [M + H](+) ion using tandem mass spectrometry. The quantification of LSD was achieved using stable-isotope-labeled LSD (LSD-d(3)) as the internal standard. The [M + H](+) ion fragmented to produce a dominant fragment ion, which was used for a selected reaction monitoring (SRM) method for quantitative analysis of LSD. SRM was compared with selected ion monitoring and produced a wider linear range and lower limit of quantification. For SRM analysis of samples of LSD spiked in urine, the calibration curve was linear in the range of 1-100 ng/mL with a coefficient of determination, r(2), of 0.9917. This assay was used to determine LSD in urine samples and the AP MALDI-MS results were comparable to the HPLC/ ESI-MS results.

Analysis of metalaxyl racemate using high performance liquid chromatography coupled with four kinds of detectors.

PubMed

Chen, Tao; Fan, Jun; Gao, Ruiqi; Wang, Tai; Yu, Ying; Zhang, Weiguang

2016-10-07

Chiral stationary phase-high performance liquid chromatography coupled with various detectors has been one of most commonly used methods for analysis and separation of chiral compounds over the past decades. Various detectors exhibit different characteristics in qualitative and quantitative studies under different chromatographic conditions. Herein, a comparative evaluation of HPLC coupled with ultraviolet, optical rotation, refractive index, and evaporative light scattering detectors has been conducted for qualitative and quantitative analyses of metalaxyl racemate. Effects of separation conditions on the peak area ratio between two enantiomers, including sample concentration, column temperature, mobile phase composition, as well as flow rate, have been investigated in detail. In addition, the limits of detection, the limits of quantitation, quantitative range and precision for these two enantiomers by using four detectors have been also studied. As indicated, the chromatographic separation conditions have been slight effects on ultraviolet and refractive index detections and the peak area ratio between two enantiomers remains almost unchanged, but the evaporative light scattering detection has been significantly affected by the above-mentioned chromatographic conditions and the corresponding peak area ratios varied greatly. Moreover, the limits of detection, the limits of quantitation, and the quantitative ranges of two enantiomers with UV detection were remarkably lower by 1-2 magnitudes than the others. Copyright © 2016 Elsevier B.V. All rights reserved.

Quantitative determination of major active components in Ginkgo biloba dietary supplements by liquid chromatography/mass spectrometry.

PubMed

Ding, Shujing; Dudley, Ed; Plummer, Sue; Tang, Jiandong; Newton, Russell P; Brenton, A Gareth

2006-01-01

A reversed-phase high-performance liquid chromatography/electrospray ionisation mass spectrometry (RP-HPLC/ESI-MS) method was developed and validated for the simultaneous determination of ten major active components in Ginkgo biloba extract (bilobalide, ginkgolides A, B, C, quercetin, kaempferol, isorhamnetin, rutin hydrate, quercetin-3-beta-D-glucoside and quercitrin hydrate) which have not been previously reported to be quantified in a single analysis. The ten components exhibit baseline separation in 50 min by C18 chromatography using a water/1:1 (v/v) methanol/acetonitrile gradient. Quantitation was performed using negative ESI-MS in selected ion monitoring (SIM) mode. Good reproducibility and recovery were obtained by this method. The sensitivity of both UV and different mass spectrometry modes (full scan, selected ion monitoring (SIM), and selected reaction monitoring (SRM)) were compared and both quantitation with and without internal standard were evaluated. The analysis of Ginkgo biloba commercial products showed remarkable variations in the rutin and quercetin content as well as the terpene lactone contents although all the products satisfy the conventional quality control method. Copyright 2006 John Wiley & Sons, Ltd.

Simultaneous identification/determination system for phentolamine and sildenafil as adulterants in soft drinks advertising roborant nutrition.

PubMed

Mikami, Eiichi; Ohno, Tsutomu; Matsumoto, Hiroshi

2002-12-04

An easily available, simultaneous identification/determination procedure for phentolamine (PHE) and sildenafil (SIL) in adulterated dietary supplements was established by using a combination of three different analytical methods; thin-layer chromatography (TLC), liquid chromatography-mass spectrometry (LC/MS) and a high-performance liquid chromatography (HPLC)/photo-diode-array. The sample solution for TLC was applied to silica gel 60 F(254) plates with chloroform/ammonia solution (28)/methanol (70:5:3, lower layer) and chloroform/diethylamine/methanol (15:3:2) as the developing solvent. Spots were located under UV radiation at 254 nm. Mass spectra of PHE and SIL by LC/MS were investigated with electrospray ionization (ESI) interface, under both positive and negative ion mode. The HPLC analysis was performed on a column of Wakosil 5C18 (4.6 mm x 150 mm, 5 microm) with water/methanol/acetonitrile/triethylamine (580:250:170:1) adjusted with phosphoric acid to pH 3.0 as the mobile phase, and the effluent was monitored with a photo-diode-array detector. Quantitative HPLC analysis of PHE and SIL were detected at 280 nm. When this procedure was applied to commercial soft drinks, PHE and SIL were identified and determined at a concentration of 17 mg PHE and 44 mg SIL per bottle, respectively. The procedure described here is available for the screening of PHE and SIL in adulterated supplements. Copyright 2002 Elsevier Science Ireland Ltd.

A method for the measurement of atmospheric HONO based on DNPH derivatization and HPLC analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, X.; Qiao, H.; Deng, G.

1999-10-15

A simple measurement technique was developed for atmospheric HONO based on aqueous scrubbing using a coil sampler followed by 2,4-dinitrophenylhydrazine (DNPH) derivatization and high-performance liquid chromatographic (HPLC) analysis. Quantitative sampling efficiency was obtained using a 1 mM phosphate buffer, pH 7.0, as the scrubbing solution at a gas sampling flow rate of 2 L min{sup {minus}1} and a liquid flow rate of 0.24 mL min{sup {minus}1}. Derivation of the scrubbed nitrous acid by DNPH was fast and was completed within 5 min in a derivatization medium containing 300 {micro}M DNPH and 8 mM HCI at 45 C. The azide derivativemore » was separated from DNPH reagent and carbonyl derivatives by reverse-phase HPLC and was detected with an UV detector at 309 nm. The detection limit is {le}5 pptv and may be lowered to 1 pptv with further DNPH purification. Interferences from NO, NO{sub 2} PAN, O{sub 3}, HNO{sub 3}, and HCHO were studied and found to be negligible. Ambient HONO concentration was measured simultaneously in downtown Albany, NY, by this method and by an ion chromatographic technique after sampling using a fritted bubbler. The results, from 70 pptv during the day to 1.7 ppbv in the early morning, were in very good agreement from the two techniques, within {+-} 20%.« less

Simultaneous characterisation and quantitation of flavonol glycosides and aglycones in noni leaves using a validated HPLC-UV/MS method.

PubMed

Deng, Shixin; West, Brett J; Jensen, C Jarakae

2008-11-15

The leaves of Morinda citrifolia L. (noni) have been utilized in a variety of commercial products marketed for their health benefits. This paper reports on a rapid and selective HPLC method for simultaneous characterization and quantitation of four flavonols in an ethanolic extract of noni leaves by using dual detectors of UV (365nm) and ESI-MS (negative mode). The limits of detection and quantitation were between 0.012 and 0.165μg/mL. The intra- and inter-assay precisions, in terms of percent relative standard deviation, are less than 4.38% and 3.50%, respectively. The accuracy, in terms of recovery percentage, ranged from 96.66% to 100.03%. Good linearity (correlation coefficient >0.999) for each calibration curve of standards was achieved in the range investigated. The contents of four flavonoids in the noni leaves varied from 1.16 to 371.6mg/100g dry weight. Copyright © 2008 Elsevier Ltd. All rights reserved.

High-pressure liquid chromatography analysis of antibiotic susceptibility disks.

PubMed Central

Hagel, R B; Waysek, E H; Cort, W M

1979-01-01

The analysis of antibiotic susceptibility disks by high-pressure liquid chromatography (HPLC) was investigated. Methods are presented for the potency determination of mecillinam, ampicillin, carbenicillin, and cephalothin alone and in various combinations. Good agreement between HPLC and microbiological data is observed for potency determinations with recoveries of greater than 95%. Relative standard deviations of lower than 2% are recorded for each HPLC method. HPLC methods offer improved accuracy and greater precision when compared to the standard microbiological methods of analysis for susceptibility disks. PMID:507793

Development and validation of a rapid stability indicating HPLC-method using monolithic stationary phase and two spectrophotometric methods for determination of antihistaminic acrivastine in capsules

NASA Astrophysics Data System (ADS)

Gouda, Ayman A.; Hashem, Hisham; Jira, Thomas

2014-09-01

Simple, rapid and accurate high performance liquid chromatographic (HPLC) and spectrophotometric methods are described for determination of antihistaminic acrivastine in capsules. The first method (method A) is based on accurate, sensitive and stability indicating chromatographic separation method. Chromolith® Performance RP-18e column, a relatively new packing material consisting of monolithic rods of highly porous silica, was used as stationary phase applying isocratic binary mobile phase of ACN and 25 mM NaH2PO4 pH 4.0 in the ratio of 22.5:77.5 at flow rate of 5.0 mL/min and 40 °C. A diode array detector was used at 254 nm for detection. The elution time of acrivastine was found to be 2.080 ± 0.032. The second and third methods (methods B and C) are based on the oxidation of acrivastine with excess N-bromosuccinimide (NBS) and determination of the unconsumed NBS with, metol-sulphanilic acid (λmax: 520 nm) or amaranth dye (λmax: 530 nm). The reacted oxidant corresponds to the drug content. Beer’s law is obeyed over the concentration range 1.563-50, 2.0-20 and 1.0-10 μg mL-1 for methods A, B and C, respectively. The limits of detection and quantitation were 0.40, 0.292 and 0.113 μg mL-1 and 0.782, 0.973 and 0.376 μg mL-1 for methods A, B and C, respectively. The HPLC method was validated for system suitability, linearity, precision, limits of detection and quantitation, specificity, stability and robustness. Stability tests were done through exposure of the analyte solution for four different stress conditions and the results indicate no interference of degradants with HPLC-method. The proposed methods was favorably applied for determination of acrivastine in capsules formulation. Statistical comparison of the obtained results from the analysis of the studied drug to those of the reported method using t- and F-tests showed no significant difference between them.

Development of a low-cost method of analysis for the qualitative and quantitative analysis of butyltins in environmental samples.

PubMed

Bangkedphol, Sornnarin; Keenan, Helen E; Davidson, Christine; Sakultantimetha, Arthit; Songsasen, Apisit

2008-12-01

Most analytical methods for butyltins are based on high resolution techniques with complicated sample preparation. For this study, a simple application of an analytical method was developed using High Performance Liquid Chromatography (HPLC) with UV detection. The developed method was studied to determine tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MBT) in sediment and water samples. The separation was performed in isocratic mode on an ultra cyanopropyl column with a mobile phase of hexane containing 5% THF and 0.03% acetic acid. This method was confirmed using standard GC/MS techniques and verified by statistical paired t-test method. Under the experimental conditions used, the limit of detection (LOD) of TBT and DBT were 0.70 and 0.50 microg/mL, respectively. The optimised extraction method for butyltins in water and sediment samples involved using hexane containing 0.05-0.5% tropolone and 0.2% sodium chloride in water at pH 1.7. The quantitative extraction of butyltin compounds in a certified reference material (BCR-646) and naturally contaminated samples was achieved with recoveries ranging from 95 to 108% and at %RSD 0.02-1.00%. This HPLC method and optimum extraction conditions were used to determine the contamination level of butyltins in environmental samples collected from the Forth and Clyde canal, Scotland, UK. The values obtained severely exceeded the Environmental Quality Standard (EQS) values. Although high resolution methods are utilised extensively for this type of research, the developed method is cheaper in both terms of equipment and running costs, faster in analysis time and has comparable detection limits to the alternative methods. This is advantageous not just as a confirmatory technique but also to enable further research in this field.

Development and validation of a stability-indicating RP-HPLC method for determination of atomoxetine hydrochloride in tablets.

PubMed

Patel, Sejal K; Patel, Natvarlal J

2010-01-01

This paper describes the development of a stability-indicating RP-HPLC method for the determination of atomoxetine hydrochloride (ATX) in the presence of its degradation products generated from forced decomposition studies. The drug substance was subjected to stress conditions of acid, base, oxidation, wet heat, dry heat, and photodegradation. In stability tests, the drug was susceptible to acid, base, oxidation, and dry and wet heat degradation. It was found to be stable under the photolytic conditions tested. The drug was successfully separated from the degradation products formed under stress conditions on a Phenomenex C18 column (250 x 4.6 mm id, 5 microm particle size) by using acetonitrile-methanol-0.032 M ammonium acetate (55 + 05 + 40, v/v/v) as the mobile phase at 1.0 mL/min and 40 degrees C. Photodiode array detection at 275 nm was used for quantitation after RP-HPLC over the concentration range of 0.5-5 microg/mL with a mean recovery of 100.8 +/- 0.4% for ATX. Statistical analysis demonstrated that the method is repeatable, specific, and accurate for the estimation of ATX. Because the method effectively separates the drug from its degradation products, it can be used as a stability-indicating method.

Utilization of Photochemically Induced Fluorescence Detection for HPLC Determination of Genotoxic Impurities in the Vortioxetine Manufacturing Process.

PubMed

Douša, Michal; Doubský, Jan; Srbek, Jan

2016-07-01

An analytical reversed-phase high-performance liquid chromatography (HPLC) method for the detection and quantitative determination of two genotoxic impurities at ppm level present in the vortioxetine manufacturing process is described. Applying the concept of threshold of toxicological concern, a limit of 75 ppm each for both genotoxic impurities was calculated based on the maximum daily dose of active pharmaceutical ingredients. The novel reversed-phase HPLC method with photochemically induced fluorescence detection was developed on XSELECT Charged Surface Hybrid Phenyl-Hexyl column using the mobile phase consisted a mixture of 10 mM ammonium formate pH 3.0 and acetonitrile. The elution was performed using an isocratic composition of 48:52 (v/v) at a flow rate of 1.0 mL/min. The photochemically induced fluorescence detection is based on the use of UV irradiation at 254 nm through measuring the fluorescence intensity at 300 nm and an excitation wavelength of 272 nm to produce fluorescent derivatives of both genotoxic impurities. The online photochemical conversion and detection is easily accomplished for two expected genotoxic impurities and provides a sufficiently low limit detection and quantification for the target analysis. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Occupational exposure to rubber vulcanization products during repair of rubber conveyor belts in a brown coal mine.

PubMed

Gromiec, Jan P; Wesołowski, Wiktor; Brzeźnicki, Sławomir; Wróblewska-Jakubowska, Krystyna; Kucharska, Małgorzata

2002-12-01

Several hundred chemical compounds were found in workroom environments in the rubber industry, but most of the published exposure data relate to the production of tyres; information from the "non-tyre" sections are very limited, if any. This study was carried out to identify chemical substances and measure their air concentrations in the repair shop of a brown coal mine in which damaged rubber conveyor belts were repaired. GC-MS and HPLC analysis of stationary air samples resulted in identification of aliphatic and aromatic hydrocarbons to C12, PAHs, alcohols, phenols, ketones, heterocyclic nitrogen and sulfur compounds. Quantitative evaluation of occupational exposure included determination of organic compound vapours collected on charcoal (GC-MSD), polycyclic aromatic hydrocarbons (HPLC), N-nitrosoamines and other amines (GC-NPD) and DNPH derivatives of aldehydes (HPLC) in the breathing zone of workers representing all job titles. The concentrations of investigated compounds were very low. Carcinogenic substances: N-nitrosoamines, benzene, PAHs were not present in workroom air in concentrations exceeding limits of detection of the analytical methods being applied; concentrations of methylisobutylketone, tetrachloroethylene, naphtha, aromatic hydrocarbons, phthalates and aldehydes were much lower than the respective occupational exposure limit values. The results indicate much lower exposure than that reported in the production of tyres and other fabricated rubber products.

Analysis of phytochemical variations in dioecious Tinospora cordifolia stems using HPLC/QTOF MS/MS and UPLC/QqQLIT -MS/MS.

PubMed

Bajpai, Vikas; Singh, Awantika; Chandra, Preeti; Negi, M P S; Kumar, Nikhil; Kumar, Brijesh

2016-01-01

The stem of dioecious Tinospora cordifolia (Menispermaceae) is a commonly used traditional Ayurvedic medicine in India having several therapeutic properties. To develop and validate LC-MS methods for the identification and simultaneous quantitation of various secondary metabolites and to study metabolomic variations in the stem of male and female plants. Ethanolic extract of stems were analysed by HPLC/ESI-QTOF-MS/MS for rapid screening of bioactive phytochemicals. High resolution MS and MS/MS in positive ESI mode were used for structural investigation of secondary metabolites. An UPLC/ESI-QqQ(LIT) -MS/MS method in MRM mode was developed and validated for the simultaneous quantitation of five bioactive alkaloids. Identification and characterisation of 36 metabolites including alkaloids, sesquiterpenes and phytoecdysteroids were performed using LC-MS and MS/MS techniques. The bioactive alkaloids such as jatrorrhizine, magnoflorine, isocorydine, palmatine and tetrahydropalmatine were successfully quantified in male and female plants. The mean abundances of magnoflorine jatrorrhizine, and oblongine were significantly (P < 0.05) higher in male plants while mean abundances of tetrahydropalmatine, norcoclaurine, and reticuline were significantly (P < 0.05) higher in female plants. Phytochemicals in the stem of male and female Tinospora cordifolia showed significant qualitative and quantitative variations. LC-MS and MS/MS methods can be used to differentiate between male and female plants based on their chemical profiles and quantities of the marker bioactive alkaloids. This chemical composition difference was also evident during vegetative stage when there were no male and female flowers. Copyright © 2015 John Wiley & Sons, Ltd.

Rapid analysis of Aurantii Fructus Immaturus (Zhishi) using paper spray ionization mass spectrometry.

PubMed

Liu, Xuemei; Gu, Zhixin; Guo, Yuan; Liu, Jingjing; Ma, Ming; Chen, Bo; Wang, Liping

2017-04-15

Paper spray-mass spectrometry (PS-MS) is a rapid, solvent-efficient, and high-throughput analytical method for analyzing complex samples. In this study, a PS-MS method was developed to obtain MS profiles of Aurantii Fructus Immaturus (aka Zhishi in Chinese) in positive and negative ion modes. In combination with multivariate analyses, including principal component analysis and cluster analysis, the PS-MS profiles of 25 batches of Zhishi were discriminated in 25 batches of Citri Reticulatae Pericarpium Viride (aka Qingpi in Chinese; an adulterant of Zhishi). Moreover, a rapid quantitative analysis of synephrine, a prescriptive quality control component of Zhishi listed in the Chinese Pharmacopoeia, was conducted with PS-MS using synephrine-d2 as an internal standard (IS). The linearity range was 1.68-16.8μg/mL (R 2 =0.9985), the limit of quantitation was 0.5μg/mL. Relative standard deviations in the intra- and inter-day precision of the MS were 4.87 and 4.90%, respectively. Compared with HPLC results, there was no significant difference in the quantitation of synephrine. This study demonstrated that the PS-MS method is useful for the rapid discrimination and quality control of Zhishi samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Analysis of Poly-β-Hydroxybutyrate in Rhizobium japonicum Bacteroids by Ion-Exclusion High-Pressure Liquid Chromatography and UV Detection †

PubMed Central

Karr, Dale B.; Waters, James K.; Emerich, David W.

1983-01-01

Ion-exclusion high-pressure liquid chromatography (HPLC) was used to measure poly-β-hydroxybutyrate (PHB) in Rhizobium japonicum bacteroids. The products in the acid digest of PHB-containing material were fractionated by HPLC on Aminex HPX-87H ion-exclusion resin for organic acid analysis. Crotonic acid formed from PHB during acid digestion was detected by its intense absorbance at 210 nm. The Aminex-HPLC method provides a rapid and simple chromatographic technique for routine analysis of organic acids. Results of PHB analysis by Aminex-HPLC were confirmed by gas chromatography and spectrophotometric analysis. PMID:16346443

High Performance Liquid Chromatography-Diode Array Detector Method for the Simultaneous Determination of Five Compounds in the Pulp and Seed of Sea Buckthorn.

PubMed

Zhao, Lu; Wen, E; Upur, Halmuart; Tian, Shuge

2017-01-01

Sea buckthorn ( Hippophae rhamnoides L.) as a traditional Chinese medicinal plant has various uses in Xinjiang. A reversed-phase rapid-resolution liquid-chromatography method with diode array detector was developed for simultaneous determination of protocatechuic acid, rutin, quercetin, kaempferol, and isorhamnetin in the pulp and seed of sea buckthorn, a widely used traditional Chinese medicine for promoting metabolism and treating scurvy and other diseases. Compounds were separated on an Agilent ZORBAX SB-C18 column (4.6 mm × 250 mm, 5 μm; USA) with gradient elution using methanol and 0.4% phosphoric acid (v/v) at 1.0 mL/min. Detection wavelength was set at 280 nm. The fruits of wild sea buckthorn were collected from Wushi County in Aksu, Xinjiang Province. The RSD of precision test of the five compounds were in the range of 0.60-2.22%, and the average recoveries ranged from 97.36% to 101.19%. Good linearity between specific chromatographic peak and component qualities were observed in the investigated ranges for all the analytes ( R 2 > 0.9997). The proposed method was successfully applied to determine the levels of five active components in sea buckthorn samples from Aksu in Xinjiang. The proposed method is simple, fast, sensitive, accurate, and suitable for quantitative assessment of the pulp and seed of sea buckthorn. Quantitative analysis method of protocatechuic acid, rutin, quercetin, kaempferol, and isorhamnetin in the extract of sea buckthorn pulp and seed is developed by high-performance liquid chromatography (HPLC) diode array detection.This method is simple and accurate; has strong specificity, good precision, and high recovery rate; and provides a reliable basis for further development of the substances in the pulp and seed of sea buckthorn.The method is widely used for content determination of active ingredients or physiologically active components in traditional Chinese medicine and its preparation Abbreviation used: PR: protocatechuic acid, RU: rutin, QU: quercetin, KA: kaempferol, IS: isorhamnetin, HPLC: high-performance liquid chromatography, HPLC-DAD: high performance liquid chromatographydiode array detector, LOD: linearity and limit of detection, LOQ: limit of quantitation, RSD: relative standard deviation.

Quantitative Analysis of Apisin, a Major Protein Unique to Royal Jelly

PubMed Central

Arai, Yasuko; Kato, Kenji

2016-01-01

Apisin, a protein that is unique to royal jelly (RJ), is known to compose the greater part of the RJ proteins and to exist as a heterooligomer containing major royal jelly protein 1 and apisimin. However, few reports on the methods for quantifying apisin have been published. Thus, we attempted to quantify apisin using HPLC, a widely used analytical technique, as described below. Isoelectric precipitation and size-exclusion chromatography were used to obtain the purified protein, which was identified as apisin by SDS-PAGE and LC-MS analyses. The purified apisin was lyophilized and then used to generate a calibration curve to quantify apisin in RJ. The apisin content was fairly constant (i.e., 3.93 to 4.67 w/w%) in natural RJ. This study is the first to describe a simple, standardized method for quantifying apisin using HPLC and suggests that apisin can be used as a benchmark for future evaluations of RJ quality. PMID:27721892

A novel strategy for rapid quantification of 20(S)-protopanaxatriol and 20(S)-protopanaxadiol saponins in Panax notoginseng P. ginseng and P. quinquefolium.

PubMed

Xu, Fa-Xiang; Yuan, Cen; Wan, Jian-Bo; Yan, Ru; Hu, Hao; Li, Shao-Ping; Zhang, Qing-Wen

2015-01-01

A novel strategy for the qualitative and quantitative determination of 20(S)-protopanaxatriol saponins (PTS) and 20(S)-protopanaxadiol saponins (PDS) in Panax notoginseng, Panax ginseng and Panax quinquefolium, based on the overlapping peaks of main components of PTS (calibrated by ginsenoside Rg1) and PDS (calibrated by ginsenoside Rb1), was proposed. The analysis was performed by using high-performance liquid chromatography coupled with evaporative light scattering detection (HPLC-ELSD). Under specific chromatographic conditions, all samples showed two overlapping peaks containing several main ginsenosides belonging to PTS and PDS, respectively. The overlapping peaks were also identified by using HPLC-MS. Based on the sum and ratio of PTS and PDS, 60 tested Panax samples were divided into three main clusters according to their species. The findings suggested that this strategy provides a simple and rapid approach to quantify PTS and PDS in Panax herbs.

Microwave-assisted extraction, HPLC analysis, and inhibitory effects on carbonic anhydrase I, II, VA, and VII isoforms of 14 blueberry Italian cultivars.

PubMed

Mollica, Adriano; Locatelli, Marcello; Macedonio, Giorgia; Carradori, Simone; Sobolev, Anatoly P; De Salvador, Roberto F; Monti, Simona M; Buonanno, Martina; Zengin, Gokhan; Angeli, Andrea; Supuran, Claudiu T

2016-01-01

The multi-component fingerprint and the biological evaluation of plant-derived material are indispensable for the pharmaceutical field, in food quality control procedures, and in all plant-based products. We investigated the quantitative content of biologically active compounds (anthocyanins and chlorogenic acid) of microwave-assisted blueberry extracts from 14 different Italian cultivars, using validated high-performance liquid chromatography-photodiode array detector (HPLC-PDA) method and routinely instrument configuration. The carbonic anhydrase (CA, EC 4.2.1.1) inhibition profiles against several pharmacologically relevant CA isoforms of blueberry extracts and some bioactive compounds were also investigated. The various cultivars showed a highly variable content in anthocyanins and chlorogenic acid, and their CA inhibitory effects were also highly variable. Overall these data prove that antioxidant natural products found in blueberries may be useful for designing pharmacological agents in which various CAs are involved, e.g., antiobesity, antitumor, or anticonvulsants agents.

Identification and quantitation of vitamins K1 and K3 in cosmetic products for facial skin protection.

PubMed

De Orsi, D; Giannini, G; Gagliardi, L; Carpani, I; Tonelli, D

2008-01-01

A simple and rapid analytical method was developed for the determination of vitamins K1 and K3 in facial anti-rash creams. The procedure is based on an ultrasonic extraction of the cosmetic sample with dimethylacetamide, in the presence of an internal standard, followed by HPLC separation. HPLC was performed using a C18 column and spectrophotometric detection at 333 nm. A linear gradient elution was carried out starting with 50% acetonitrile-methanol (75:25 v/v) and water up to 100% acetonitrile-methanol for 5 min. Linearity was established over the concentration range from 0.2 to 1.0 mg/ml for vitamin K1 and from 0.02 to 0.1 mg/ml for vitamin K3, with LOD values of 100 ng and 20 ng injected, respectively. The accuracy was verified by spiking experiments on model cosmetic samples. The proposed method has been successfully applied for the analysis of commercial samples of creams.

The Third SeaWiFS HPLC Analysis Round-Robin Experiment (SeaHARRE-3)

NASA Technical Reports Server (NTRS)

Hooker, Stanford B.; VanHeukelem, Laurei; Thomas, Crystal S.; Claustre, Herve; Ras, Josephine; Schluter, Louise; Clementson, Lesley; vanderLinde, Dirk; Eker-Develi, Elif; Berthon, Jean-Francois;

Chemical analysis and quality control of Ginkgo biloba leaves, extracts, and phytopharmaceuticals.

PubMed

van Beek, Teris A; Montoro, Paola

2009-03-13

The chemical analysis and quality control of Ginkgo leaves, extracts, phytopharmaceuticals and some herbal supplements is comprehensively reviewed. The review is an update of a similar, earlier review in this journal [T.A. van Beek, J. Chromatogr. A 967 (2002) 21-55]. Since 2001 over 3000 papers on Ginkgo biloba have appeared, and about 400 of them pertain to chemical analysis in a broad sense and are cited herein. The more important ones are discussed and, where relevant, compared with the best methods published prior to 2002. In the same period over 2500 patents were filed on Ginkgo and the very few related to analysis are mentioned as well. Important constituents include terpene trilactones, i.e. ginkgolide A, B, C, J and bilobalide, flavonol glycosides, biflavones, proanthocyanidins, alkylphenols, simple phenolic acids, 6-hydroxykynurenic acid, 4-O-methylpyridoxine and polyprenols. In the most common so-called "standardised" Ginkgo extracts and phytopharmaceuticals several of these classes are no longer present. About 130 new papers deal with the analysis of the terpene trilactones. They are mostly extracted with methanol or water or mixtures thereof. Supercritical fluid extraction and pressurised water extraction are also possible. Sample clean-up is mostly by liquid-liquid extraction with ethyl acetate although no sample clean-up at all in combination with LC/MS/MS is gaining in importance. Separation and detection can be routinely carried out by RP-HPLC with ELSD, RI or MS, or by GC/FID or GC/MS after silylation. Hydrolysis followed by LC/MS allows the simultaneous analysis of terpene trilactones and flavonol aglycones. No quantitative procedure for all major flavonol glycosides has yet been published because they are not commercially available. The quantitation of a few available glycosides has been carried out but does not serve a real purpose. After acidic hydrolysis to the aglycones quercetin, kaempferol and isorhamnetin and separation by HPLC, quantitation is straightforward and yields by recalculation an estimation of the original total flavonol glycoside content. A profile of the genuine flavonol glycosides can detect poor storage or adulteration. Although the toxicity of Ginkgo alkylphenols upon oral administration has never been undoubtedly proven, most suppliers limit their content in extracts to 5 ppm and dozens of papers on their analysis were published. One procedure in which a methanolic extract is directly injected on a C8 HPLC column appears superior in terms of sensitivity (<5 ppm), separation, simplicity and validation and will be incorporated in the European Pharmacopoeia. Alternatively GC/MS and ELISA methods can be used. A sharp contrast to the plethora of papers on terpene trilactones, flavonol glycosides, and ginkgolic acids forms the low number of papers on biflavones, proanthocyanidins, simple phenolics, simple acids, and other constituents that make up the remaining 70% of Ginkgo standardised extracts. More research in this direction is clearly needed. For the analysis of Ginkgo proanthocyanidins (7%) for instance, no reliable assays are yet existing. Finally the growing literature on pharmacokinetic and fingerprinting studies of Ginkgo is briefly summarised.

Quantitative structure-retention relationship models for the prediction of the reversed-phase HPLC gradient retention based on the heuristic method and support vector machine.

PubMed

Du, Hongying; Wang, Jie; Yao, Xiaojun; Hu, Zhide

2009-01-01

The heuristic method (HM) and support vector machine (SVM) were used to construct quantitative structure-retention relationship models by a series of compounds to predict the gradient retention times of reversed-phase high-performance liquid chromatography (HPLC) in three different columns. The aims of this investigation were to predict the retention times of multifarious compounds, to find the main properties of the three columns, and to indicate the theory of separation procedures. In our method, we correlated the retention times of many diverse structural analytes in three columns (Symmetry C18, Chromolith, and SG-MIX) with their representative molecular descriptors, calculated from the molecular structures alone. HM was used to select the most important molecular descriptors and build linear regression models. Furthermore, non-linear regression models were built using the SVM method; the performance of the SVM models were better than that of the HM models, and the prediction results were in good agreement with the experimental values. This paper could give some insights into the factors that were likely to govern the gradient retention process of the three investigated HPLC columns, which could theoretically supervise the practical experiment.

Demonstration and Evaluation of Solid Phase Microextraction for the Assessment of Bioavailability and Contaminant Mobility

DTIC Science & Technology

2012-05-01

methods demonstrated that desorption into solvents suitable for subsequent chemical analysis (into acetonitrile for HPLC analysis or hexane for GC...SPME. Analysis by HPLC with EPA 8310 with fluorescent detection. a) surface water quality criteria (NRWQC) are given for comparison to detection... analysis ) or hexane (for PCB analysis ) was added to the inserts. The vials were then analyzed directly by HPLC (PAHs) or GC-ECD (PCBs). Fiber achieved

Determination of nitrate esters in water samples Comparison of efficiency of solid-phase extraction and solid-phase microextraction.

PubMed

Jezová, Vera; Skládal, Jan; Eisner, Ales; Bajerová, Petra; Ventura, Karel

2007-12-07

This paper deals with comparison of efficiency of extraction techniques (solid-phase extraction, SPE and solid-phase microextraction, SPME) used for extraction of nitrate esters (ethyleneglycoldinitrate, EGDN and nitroglycerin, NG), representing the first step of the method of quantitative determination of trace concentrations of nitrate esters in water samples. EGDN and NG are subsequently determined by means of high-performance liquid chromatography with ultraviolet detection (HPLC-UV). Optimization of SPE and SPME conditions was carried out using model water samples. Seven SPE cartridges were tested and the conditions were optimized (type of sorbent, type and volume of solvent to be used as eluent). For both nitrate esters the limit of detection (LOD) and the limit of quantification (LOQ) obtained using SPE/HPLC-UV were 0.23 microg mL(-1) and 0.70 microg mL(-1), respectively. Optimization of SPME conditions: type of SPME fibre (four fibres were tested), type and time of sorption/desorption, temperature of sorption. PDMS/DVB (polydimethylsiloxane/divinylbenzene) fibre coating proved to be suitable for extraction of EGDN and NG. For this fibre the LOD and the LOQ for both nitrate esters were 0.16 microg mL(-1) and 0.50 microg mL(-1), respectively. Optimized methods SPE/HPLC-UV and SPME/HPLC-UV were then used for quantitative determination of nitrate esters content in real water samples from the production of EGDN and NG.

Quantification of cortisol in human eccrine sweat by liquid chromatography - tandem mass spectrometry.

PubMed

Jia, Min; Chew, Wade M; Feinstein, Yelena; Skeath, Perry; Sternberg, Esther M

2016-03-21

Cortisol has long been recognized as the "stress biomarker" in evaluating stress related disorders. Plasma, urine or saliva are the current source for cortisol analysis. The sampling of these biofluids is either invasive or has reliability problems that could lead to inaccurate results. Sweat has drawn increasing attention as a promising source for non-invasive stress analysis. A sensitive HPLC-MS/MS method was developed for the quantitation of cortisol ((11β)-11,17,21-trihydroxypregn-4-ene-3,20-dione) in human eccrine sweat. At least one unknown isomer that has previously not been reported and could potentially interfere with quantification was separated from cortisol with mixed mode RP HPLC. Detection of cortisol was carried out using atmospheric pressure chemical ionization (APCI) and selected reaction monitoring (SRM) in positive ion mode, using cortisol-9,11,12,12-D4 as internal standard. LOD and LOQ were estimated to be 0.04 ng ml(-1) and 0.1 ng ml(-1), respectively. Linear range of 0.10-25.00 ng ml(-1) was obtained. Intraday precision (2.5%-9.7%) and accuracy (0.5%-2.1%), interday precision (12.3%-18.7%) and accuracy (7.1%-15.1%) were achieved. This method has been successfully applied to the cortisol analysis of human eccrine sweat samples. This is the first demonstration that HPLC-MS/MS can be used for the sensitive and highly specific determination of cortisol in human eccrine sweat in the presence of at least one isomer that has similar hydrophobicity as cortisol. This study demonstrated that human eccrine sweat could be used as a promising source for non-invasive assessment of stress biomarkers such as cortisol and other steroid hormones.

Does Uniformity of Topical Corticosteroid Ophthalmic Medications: Flourometholone Acetate 0.1 Suspension and Loteprednol Etabonate 0.5 gel

DTIC Science & Technology

2017-01-03

chromatography ( HPLC ) with photodiode array detection at 240 nm. Results: Flarex® had a mean concentration of 93.7% of the declared concentration when shaken...59 60 Journal of Ocular Pharmacology and Therapeutics Charlton E Stevens Rockville, MD. Methanol, ( HPLC grade), was obtained from Sigma-Aldrich...ST. Louis, MO. HPLC analysis of fluorometholone acetate and loteprednol etabonate HPLC analysis of fluorometholone acetate and loteprednol

Analytical Eco-Scale for Assessing the Greenness of a Developed RP-HPLC Method Used for Simultaneous Analysis of Combined Antihypertensive Medications.

PubMed

Mohamed, Heba M; Lamie, Nesrine T

2016-09-01

In the past few decades the analytical community has been focused on eliminating or reducing the usage of hazardous chemicals and solvents, in different analytical methodologies, that have been ascertained to be extremely dangerous to human health and environment. In this context, environmentally friendly, green, or clean practices have been implemented in different research areas. This study presents a greener alternative of conventional RP-HPLC methods for the simultaneous determination and quantitative analysis of a pharmaceutical ternary mixture composed of telmisartan, hydrochlorothiazide, and amlodipine besylate, using an ecofriendly mobile phase and short run time with the least amount of waste production. This solvent-replacement approach was feasible without compromising method performance criteria, such as separation efficiency, peak symmetry, and chromatographic retention. The greenness profile of the proposed method was assessed and compared with reported conventional methods using the analytical Eco-Scale as an assessment tool. The proposed method was found to be greener in terms of usage of hazardous chemicals and solvents, energy consumption, and production of waste. The proposed method can be safely used for the routine analysis of the studied pharmaceutical ternary mixture with a minimal detrimental impact on human health and the environment.

[Identification of two varieties of Citri Fructus by fingerprint and chemometrics].

PubMed

Su, Jing-hua; Zhang, Chao; Sun, Lei; Gu, Bing-ren; Ma, Shuang-cheng

2015-06-01

Citri Fructus identification by fingerprint and chemometrics was investigated in this paper. Twenty-three Citri Fructus samples were collected which referred to two varieties as Cirtus wilsonii and C. medica recorded in Chinese Pharmacopoeia. HPLC chromatograms were obtained. The components were partly identified by reference substances, and then common pattern was established for chemometrics analysis. Similarity analysis, principal component analysis (PCA) , partial least squares-discriminant analysis (PLS-DA) and hierarchical cluster analysis heatmap were applied. The results indicated that C. wilsonii and C. medica could be ideally classified with common pattern contained twenty-five characteristic peaks. Besides, preliminary pattern recognition had verified the chemometrics analytical results. Absolute peak area (APA) was used for relevant quantitative analysis, results showed the differences between two varieties and it was valuable for further quality control as selection of characteristic components.

Interaction between different extracts of Hypericum perforatum L. from Serbia and pentobarbital, diazepam and paracetamol.

PubMed

Rašković, Aleksandar; Cvejić, Jelena; Stilinović, Nebojša; Goločorbin-Kon, Svetlana; Vukmirović, Saša; Mimica-Dukić, Neda; Mikov, Momir

2014-03-28

Herb-drug interactions are an important safety concern and this study was conducted regarding the interaction between the natural top-selling antidepressant remedy Hypericum perforatum (Hypericaceae) and conventional drugs. This study examined the influence of acute pretreatment with different extracts of Hypericum perforatum from Serbia on pentobarbital-induced sleeping time, impairment of motor coordination caused by diazepam and paracetamol pharmacokinetics in mice. Ethanolic extract, aqueous extract, infusion, tablet and capsule of Hypericum perforatum were used in this experiment. The profile of Hypericum perforatum extracts as well as paracetamol plasma concentration was determined using RP-HPLC analysis. By quantitative HPLC analysis of active principles, it has been proven that Hypericum perforatum ethanolic extract has the largest content of naphtodianthrones: hypericin (57.77 µg/mL) and pseudohypericin (155.38 µg/mL). Pretreatment with ethanolic extract of Hypericum perforatum potentiated the hypnotic effect of pentobarbital and impairment of motor coordination caused by diazepam to the greatest extent and also increased paracetamol plasma concentration in comparison to the control group. These results were in correlation with naphtodianthrone concentrations. The obtained results have shown a considerable influence of Hypericum perforatum on pentobarbital and diazepam pharmacodynamics and paracetamol pharmacokinetics.

Characterization of flavonoid glycosides from fenugreek (Trigonella foenum-graecum) crude seeds by HPLC-DAD-ESI/MS analysis.

PubMed

Benayad, Zakia; Gómez-Cordovés, Carmen; Es-Safi, Nour Eddine

2014-11-11

Fenugreek (Trigonella foenum-graecum) is a medicinal plant which is widely used for its pharmacological properties. In this study the phenolic composition of fenugreek crude seeds originating from Morocco has been investigated. Extraction was performed from defatted seeds by a hydromethanolic solution using an Accelerated Solvent Extractor. HPLC technique coupled to negative ion electrospray ionization mass spectrometry and diode array detection was employed to identify the polyphenol in the obtained extract. The obtained results allowed the detection of 32 phenolic compounds among which various flavonoid glycosides and phenolic acids have been tentatively identified on the basis of their UV and MS spectra, and comparisons with standards when available, as well as with literature data. A systematic study of the obtained MS spectra and the observed fragmentation showed that most of the identified compounds were acylated and non-acylated flavonoids with apigenin, luteolin and kaempferol as aglycons. Hydroxycinnamic acids mostly dominated by caffeic acid derivatives were also detected. The quantitative analysis of the identified compounds showed that the phenolic composition of the studied crude fenugreek seeds was predominantly acylated and non-acylated flavone derivatives with apigenin as the main aglycon.

RAPID AND AUTOMATED PROCESSING OF MALDI-FTICR/MS DATA FOR N-METABOLIC LABELING IN A SHOTGUN PROTEOMICS ANALYSIS.

PubMed

Jing, Li; Amster, I Jonathan

2009-10-15

Offline high performance liquid chromatography combined with matrix assisted laser desorption and Fourier transform ion cyclotron resonance mass spectrometry (HPLC-MALDI-FTICR/MS) provides the means to rapidly analyze complex mixtures of peptides, such as those produced by proteolytic digestion of a proteome. This method is particularly useful for making quantitative measurements of changes in protein expression by using (15)N-metabolic labeling. Proteolytic digestion of combined labeled and unlabeled proteomes produces complex mixtures that with many mass overlaps when analyzed by HPLC-MALDI-FTICR/MS. A significant challenge to data analysis is the matching of pairs of peaks which represent an unlabeled peptide and its labeled counterpart. We have developed an algorithm and incorporated it into a compute program which significantly accelerates the interpretation of (15)N metabolic labeling data by automating the process of identifying unlabeled/labeled peak pairs. The algorithm takes advantage of the high resolution and mass accuracy of FTICR mass spectrometry. The algorithm is shown to be able to successfully identify the (15)N/(14)N peptide pairs and calculate peptide relative abundance ratios in highly complex mixtures from the proteolytic digest of a whole organism protein extract.

Improvement of Nicotinic Acid and Nicotinamide Analysis in Meats and Meat Products by HPLC and LC-MS/MS with Solid-Phase Extraction.

PubMed

Hiki, Asako; Yamajima, Yukiko; Uematsu, Yoko

2016-01-01

A method for nicotinic acid (NA) and nicotinamide (NAA) analysis in meats was developed. NA and NAA were extracted from meats or meat products with metaphosphate aqueous solution. The extract was cleaned up with an Oasis MCX cartridge. The cartridge was washed with 2% acetic acid (v/v) and acetic acid-methanol solution. NA and NAA were eluted with ammonia-methanol solution. NA and NAA in the eluate were chromatographed on a Scherzo SM-C18 (3.0×150 mm, 3.0 μm) column with 20 mmol/L ammonium acetate containing 0.1% acetic acid-acetonitrile (97 : 3) as a mobile phase and were monitored at 261 nm. Quantification was performed by LC and LC-MS/MS. Calibration curves showed high linearity (correlation coefficient>0.998) between 1-25 μg/mL for LC and LC-MS/MS. Recoveries were 84-108% (CV≦5.8%) by HPLC and 79-105% (CV≦9.0%) by LC-MS/MS. The limit of quantitation for NA was 0.005-0.01 g/kg and that for NAA was 0.01-0.02 g/kg.

Proteomics: from hypothesis to quantitative assay on a single platform. Guidelines for developing MRM assays using ion trap mass spectrometers.

PubMed

Han, Bomie; Higgs, Richard E

2008-09-01

High-throughput HPLC-mass spectrometry (HPLC-MS) is routinely used to profile biological samples for potential protein markers of disease, drug efficacy and toxicity. The discovery technology has advanced to the point where translating hypotheses from proteomic profiling studies into clinical use is the bottleneck to realizing the full potential of these approaches. The first step in this translation is the development and analytical validation of a higher throughput assay with improved sensitivity and selectivity relative to typical profiling assays. Multiple reaction monitoring (MRM) assays are an attractive approach for this stage of biomarker development given their improved sensitivity and specificity, the speed at which the assays can be developed and the quantitative nature of the assay. While the profiling assays are performed with ion trap mass spectrometers, MRM assays are traditionally developed in quadrupole-based mass spectrometers. Development of MRM assays from the same instrument used in the profiling analysis enables a seamless and rapid transition from hypothesis generation to validation. This report provides guidelines for rapidly developing an MRM assay using the same mass spectrometry platform used for profiling experiments (typically ion traps) and reviews methodological and analytical validation considerations. The analytical validation guidelines presented are drawn from existing practices on immunological assays and are applicable to any mass spectrometry platform technology.

Quantitative and qualitative analysis of the novel antitumor 1,3,4-oxadiazole derivative (GLB) and its metabolites using HPLC-UV and UPLC-QTOF-MS

PubMed Central

Li, Pu; Wang, Xin; Li, Jian; Meng, Zhi-Yun; Li, Shu-Chun; Li, Zhong-Jun; Lu, Ying-Yuan; Ren, Hong; Lou, Ya-Qing; Lu, Chuang; Dou, Gui-Fang; Zhang, Guo-Liang

2015-01-01

Fructose-based 3-acetyl-2,3-dihydro-1,3,4-oxadiazole (GLB) is a novel antitumor agent and belongs to glycosylated spiro-heterocyclic oxadiazole scaffold derivative. This research first reported a simple, specific, sensitive and stable high performance liquid chromatography -ultraviolet detector (HPLC-UV) method for the quantitative determination of GLB in plasma. In this method, the chromatographic separation was achieved with a reversed phase C18 column. The calibration curve for GLB was linear at 300 nm. The lower limit of quantification was 10 ng/mL. The precision, accuracy and stability of the method were validated adequately. This method was successfully applied to the pharmacokinetic study in rats for detection of GLB after oral administration. Moreover, the structures of parent compound GLB and its two major metabolites M1 and M2 were identified in plasma using an ultra performance liquid chromatography- electrospray ionization-quadrupole-time of flight- mass spectrometry (UPLC-ESI-QTOF-MS) method. Our results indicated that the di-hydroxylation (M1) and hydroxylation (M2) of GLB are the major metabolites. In conclusion, the present study provided valuable information on an analytical method for the determination of GLB and its metabolites in rats, can be used to support further developing of this antitumor agent. PMID:26148672

Identification and HPLC quantitation of the sulfides and dialk(en)yl thiosulfinates in commercial garlic products.

PubMed

Lawson, L D; Wang, Z J; Hughes, B G

1991-08-01

The content of dialk(en)yl thiosulfinates, including allicin, and their degradation products has been determined by high performance liquid chromatography (HPLC), using the respective determined extinction coefficients, for a number of commercially available garlic products. Quantitation has been achieved for the thiosulfinates; diallyl, methyl allyl, and diethyl mono-, di-, tri-, tetra-, penta-, and hexasulfides; the vinyldithiins; and (E)- and (Z)-ajoene. The thiosulfinates were found to be released only from garlic cloves and garlic powder products. The vinyldithiins and ajoenes were found only in products containing garlic macerated in vegetable oil. The diallyl, methyl allyl, and dimethyl sulfide series were the exclusive constituents found in products containing the oil of steam-distilled garlic. Typical steam-distilled garlic oil products contained about the same amount of total sulfur compounds as total thiosulfinates released from freshly homogenized garlic cloves; however, oil-macerated products contained only 20% of that amount, while garlic powder products varied from 0 to 100%. Products containing garlic powder suspended in a a gel or garlic aged in aqueous alcohol did not contain detectable amounts of these non-ionic sulfur compounds. A comparison of several brands of each type of garlic product revealed a large range in content (4-fold for oil-macerates and 33-fold for steam-distilled garlic oils), indicating the importance of analysis before garlic products are used for clinical investigations or commercial distribution.

HPLC study on the 'history' dependence of gramicidin A conformation in phospholipid model membranes.

PubMed

Bañó, M C; Braco, L; Abad, C

1989-06-19

A novel HPLC methodology for the study of gramicidin A reconstituted in model membranes has been tested in comparison with circular dichroism data. It is shown that this chromatographic technique not only corroborates most of the recent spectroscopic results but allows one to explain them in terms of mass fractions of different actual conformational species of GA in the phospholipid assemblies. In particular, the dependence of the inserted peptide configuration on the organic solvent and other parameters involved in the 'history' of the sample preparation and handling has been analyzed by HPLC in two phospholipid model systems: small unilamellar vesicles and micelles. Moreover, a slow conformational transition of GA towards a beta 6.3-helical configuration, accelerated by heat incubation, has been also chromatographically visualized and quantitatively interpreted.

Determination of Nitroaromatic, Nitramine, and Nitrate Ester Explosives in Soils Using GC-ECD

DTIC Science & Technology

1999-08-01

for supplying soils from minefields; and Dr. Paul H. Miyares, CRREL, for HPLC analysis of Fort Leonard Wood soil extracts. ii CONTENTS P reface...42 ILLUSTRATIONS Figure 1. Correlation analysis of GC-ECD concentration (mg/kg) estimates with those from HPLC -UV...kg) estimates with those from HPLC -UV analysis using splits of the same acetonitrile extract from archived soils

Quantitative O-glycomics based on improvement of the one-pot method for nonreductive O-glycan release and simultaneous stable isotope labeling with 1-(d0/d5)phenyl-3-methyl-5-pyrazolone followed by mass spectrometric analysis.

PubMed

Wang, Chengjian; Zhang, Ping; Jin, Wanjun; Li, Lingmei; Qiang, Shan; Zhang, Ying; Huang, Linjuan; Wang, Zhongfu

2017-01-06

Rapid, simple and versatile methods for quantitative analysis of glycoprotein O-glycans are urgently required for current studies on protein O-glycosylation patterns and the search for disease O-glycan biomarkers. Relative quantitation of O-glycans using stable isotope labeling followed by mass spectrometric analysis represents an ideal and promising technique. However, it is hindered by the shortage of reliable nonreductive O-glycan release methods as well as the too large or too small inconstant mass difference between the light and heavy isotope form derivatives of O-glycans, which results in difficulties during the recognition and quantitative analysis of O-glycans by mass spectrometry. Herein we report a facile and versatile O-glycan relative quantification strategy, based on an improved one-pot method that can quantitatively achieve nonreductive release and in situ chromophoric labeling of intact mucin-type O-glycans in one step. In this study, the one-pot method is optimized and applied for quantitative O-glycan release and tagging with either non-deuterated (d 0 -) or deuterated (d 5 -) 1-phenyl-3-methyl-5-pyrazolone (PMP). The obtained O-glycan derivatives feature a permanent 10-Da mass difference between the d 0 - and d 5 -PMP forms, allowing complete discrimination and comparative quantification of these isotopically labeled O-glycans by mass spectrometric techniques. Moreover, the d 0 - and d 5 -PMP derivatives of O-glycans also have a relatively high hydrophobicity as well as a strong UV adsorption, especially suitable for high-resolution separation and high-sensitivity detection by RP-HPLC-UV. We have refined the conditions for the one-pot reaction as well as the corresponding sample purification approach. The good quantitation feasibility, reliability and linearity of this strategy have been verified using bovine fetuin and porcine stomach mucin as model O-glycoproteins. Additionally, we have also successfully applied this method to the quantitative O-glycomic comparison between perch and salmon eggs by ESI-MS, MS/MS and online RP-HPLC-UV-ESI-MS/MS, demonstrating its excellent applicability to various complex biological samples. O-Linked glycoproteins, generated via a widely existing glycosylation modification process on serine (Ser) or threonine (Thr) residues of nascent proteins, play essential roles in a series of biological processes. As a type of informational molecule, the O-glycans of these glycoproteins participate directly in these biological mechanisms. Thus, the characteristic differences or changes of O-glycans in expression level usually relate to pathologies of many diseases and represent an important opportunity to uncover the functional mechanisms of various glycoprotein O-glycans. The novel strategy introduced here provides a simple and versatile analytical method for the precise quantitation of glycoprotein O-glycans by mass spectrometry, enabling rapid evaluation of the differences or changes of O-glycans in expression level. It is attractive for the field of quantitative/comparative O-glycomics, which has great significance for exploring the complex structure-function relationship of O-glycans, as well as for the search of O-glycan biomarkers of some major diseases and O-glycan related targets of some drugs. Copyright © 2016 Elsevier B.V. All rights reserved.

Identification and quantification of five macrolide antibiotics in several tissues, eggs and milk by liquid chromatography-electrospray tandem mass spectrometry.

PubMed

Dubois, M; Fluchard, D; Sior, E; Delahaut, P

2001-04-05

We present an electrospray high-performance liquid chromatographic tandem mass spectrometric (HPLC-MS-MS) method capable of determining in several tissues (muscle, kidney, liver), eggs and milk the following five macrolides: tylosin, tilmicosin, spiramycin, josamycin, erythromycin. Roxithromycin was used as an internal standard. The method uses extraction in a Tris buffer at pH 10.5, followed by protein precipitation with sodium tungstate and clean-up on an Oasis solid-phase extraction column. The HPLC separation was performed on a Purospher C18 column (125 x 3 mm I.D.) protected by a guard column, with a gradient of aqueous 0.1 M ammonium acetate-acetonitrile as the mobile phase at a flow-rate of 0.7 ml min(-1). Protonated molecules served as precursor ions for electrospray ionisation in the positive ion mode and four product ions were chosen for each analyte for multiple reaction monitoring (MRM). A validation study was conducted to confirm the five macrolides by MRM HPLC-MS-MS analysis of a negative control and fortified samples. All of the samples analysed were confirmed with four ions. The ion ratio reproducibility limit ranged from 2.4 to 15%. All compounds could be detected and quantified at half-maximum residue limits (MRLs). The method is specific, quantitative and reproducible enough to conform to European Union recommendations within the concentration range 0.5 MRL-2 MRL (accuracy: 80 to 110%, relative standard deviation: 2 to 13%). This whole method allows extraction and analysis of up to 50 samples per day.

Chromatographic methods for metabolite profiling of virus- and phytoplasma-infected plants of Echinacea purpurea.

PubMed

Pellati, Federica; Epifano, Francesco; Contaldo, Nicoletta; Orlandini, Giulia; Cavicchi, Lisa; Genovese, Salvatore; Bertelli, Davide; Benvenuti, Stefania; Curini, Massimo; Bertaccini, Assunta; Bellardi, Maria Grazia

2011-10-12

This study was focused on the effects of virus and phytoplasma infections on the production of Echinacea purpurea (L.) Moench secondary metabolites, such as caffeic acid derivatives, alkamides, and essential oil. The identification of caffeic acid derivatives and alkamides was carried out by means of high-performance liquid chromatography-diode array detection (HPLC-DAD), HPLC-electrospray ionization-mass spectrometry (ESI-MS), and MS(2). Quantitative analysis of these compounds was carried out using HPLC-DAD. The results indicated that the presence of the two pathogens significantly decreases (P < 0.05) the content of cichoric acid, the main caffeic acid derivative. Regarding the main alkamide, dodeca-2E,4E,8Z,10E/Z-tetraenoic acid isobutylamide, a significant decrease (P < 0.05) in the content of this secondary metabolite was observed in virus-infected plants in comparison with healthy plants, while in the phytoplasma-infected sample the variation of this secondary metabolite was not appreciable. The % relative area of the E/Z isomers of this alkamide was also found to change in infected samples. The gas chromatography (GC) and GC-MS analysis of E. purpurea essential oil enabled the identification of 30 compounds. The main significant differences (P < 0.05) in the semiquantitative composition were observed for three components: limonene, cis-verbenol, and verbenone. The results indicate that the presence of virus and phytoplasma has an appreciable influence on the content of E. purpurea secondary metabolites, which is an important issue in defining the commercial quality, market value, and therapeutic efficacy of this herbal drug.

Use of a multifunctional column for the determination of deoxynivalenol in grains, grain products, and processed foods.

PubMed

Bao, Lei; Oles, Carolyn J; White, Kevin D; Sapp, Chelsea; Trucksess, Mary W

2011-01-01

Deoxynivalenol (DON), also known as vomitoxin, belongs to a class of naturally occurring mycotoxins produced by Fusarium spp. DON, 12, 13-epoxy-3,7 trihydroxytrichothec-9-en-8-one, is one of the most frequently detected mycotoxins in agricultural commodities worldwide. A method consisting of extraction, filtration, column cleanup, and RP-HPLC-UV separation and quantitation was validated for the determination of DON in grains (rice and barley), grain products (whole wheat flour, white flour, wheat germ, and wheat bran), and processed foods (bread, breakfast cereals, and pretzels). A 25 g test portion was extracted with 100 mL acetonitrile-water (84 + 16, v/v). After blending for 3 min, the supernatant was applied to a multifunctional column (MycoSep 225). The purified filtrate (2 mL) was evaporated to dryness and redissolved in the mobile phase. The toxins were then subjected to RP-HPLC-UV analysis. The accuracy and repeatability characteristics of the method were determined. Recoveries of DON added at levels ranging from 0.5 to 1.5 microg/g for all test matrixes were from 75 to 98%. SD and RSD(r) ranged from 0.7 to 11.6% and 0.9 to 12.7%, respectively. Within-laboratory HorRat values were from 0.1 to 0.7 for all matrixes analyzed. The method was found to meet AOAC method performance criteria for grains, grain products, and processed foods. The identity of DON in naturally contaminated test sample extracts was confirmed by HPLC/MS/MS analysis.

Variations in chemical fingerprints and major flavonoid contents from the leaves of thirty‐one accessions of Hibiscus sabdariffa L.

PubMed Central

Wang, Jin; Cao, Xianshuang; Ferchaud, Vanessa; Jiang, Hao; Tang, Feng; Chin, Kit L.

2015-01-01

Abstract The leaves of Hibiscus sabdariffa L. have been used as traditional folk medicines for treating high blood pressure and fever. There are many accessions of H. sabdariffa L. throughout the world. To assess the chemical variations of 31 different accessions of H. sabdariffa L., fingerprinting analysis and quantitation of major flavonoids were performed by high‐performance liquid chromatography (HPLC). The HPLC method was validated for linearity, sensitivity, precision, repeatability and accuracy. A quadrupole‐time‐of‐flight mass spectrometry (Q‐TOF‐MS) was applied for the characterization of major compounds. A total of 9 compounds were identified, including 6 flavonoids and 3 phenolic acids. In the fingerprint analysis, similarity analysis (SA) and principal component analysis (PCA) were used to differentiate the 31 accessions of H. sabdariffa L. Based on the results of PCA and SA, the samples No. 15 and 19 appeared much different from the main group. The total content of five flavonoids varied greatly among different accessions, ranging from 3.35 to 23.30 mg/g. Rutin was found to be the dominant compound and the content of rutin could contribute to chemical variations among different accessions. This study was helpful to understand the chemical variations between different accessions of H. sabdariffa L., which could be used for quality control. © 2015 The Authors Biomedical Chromatography Published by John Wiley & Sons Ltd. PMID:26394363

Quantitative analysis of matrine in liquid crystalline nanoparticles by HPLC.

PubMed

Peng, Xinsheng; Li, Baohong; Hu, Min; Ling, Yahao; Tian, Yuan; Zhou, Yanxing; Zhou, Yanfang

2014-01-01

A reversed-phase high-performance liquid chromatographic method has been developed to quantitatively determine matrine in liquid crystal nanoparticles. The chromatographic method is carried out using an isocratic system. The mobile phase was composed of methanol-PBS(pH6.8)-triethylamine (50 : 50 : 0.1%) with a flow rate of 1 mL/min with SPD-20A UV/vis detector and the detection wavelength was at 220 nm. The linearity of matrine is in the range of 1.6 to 200.0  μ g/mL. The regression equation is y = 10706x - 2959 (R (2) = 1.0). The average recovery is 101.7%; RSD = 2.22%  (n = 9). This method provides a simple and accurate strategy to determine matrine in liquid crystalline nanoparticle.

Quantitative determination of the dual COX-2/5-LOX inhibitor tryptanthrin in Isatis tinctoria by ESI-LC-MS.

PubMed

Danz, Henning; Baumann, Dietmar; Hamburger, Matthias

2002-02-01

Isatis tinctoria L. is an old European and Chinese dye plant and anti-inflammatory herb from which the potent cyclooxygenase-2 and 5-lipoxygenase inhibitor tryptanthrin (1) (indolo-[2,1-b]-quinazoline-6,12-dione) was recently isolated as one of the active principles. An HPLC method for the quantitative analysis of the compound in plant material was developed. Reproducible extraction was achieved by accelerated solvent extraction (ASE). Detection by UV at 254 and 387 nm and by electrospray-MS were compared. The low tryptanthrin content in the herb and possible interferences required isocratic high-performance liquid chromatography coupled with electrospray-MS in single ion mode. More than 70 Isatis samples of different origin were analyzed. The tryptanthrin content in leaf samples varied from 0.56 to 16.74 x 10(-3) %.

Quantification of terpene trilactones in Ginkgo biloba with a 1H NMR method.

PubMed

Liang, Tingfu; Miyakawa, Takuya; Yang, Jinwei; Ishikawa, Tsutomu; Tanokura, Masaru

2018-06-01

Ginkgo biloba L. has been used as a herbal medicine in the traditional treatment of insufficient blood flow, memory deficits, and cerebral insufficiency. The terpene trilactone components, the bioactive agents of Ginkgo biloba L., have also been reported to exhibit useful functionality such as anti-inflammatory and neuroprotective effects. Therefore, in the present research, we attempted to analyze quantitatively the terpene trilactone components in Ginkgo biloba leaf extract, with quantitative 1 H NMR (qNMR) and obtained almost identical results to data reported using HPLC. Application of the qNMR method for the analysis of the terpene trilactone contents in commercial Ginkgo extract products, such as soft gel capsules and tablets, produced the same levels noted in package labels. Thus, qNMR is an alternative method for quantification of the terpene trilactone components in commercial Ginkgo extract products.

[Contribution to the phytochemical study of polyphenols in ten hydroalcoholic extracts of Chamomile floss].

PubMed

Cioancă, Oana; Hăncianu, Monica; Spac, A; Miron, Anca; Stănescu, Ursula

2009-01-01

Continuing a series of studies that intend to evaluate the pharmaceutical quality of 10 commercial samples of chamomile, we tried to investigate the chemical composition of the hydroalcoholic extracts obtained in our laboratory, starting from this raw material. The qualitative and semiquantitative analysis of the extracts was done by HPLC means. All extractive solutions have a high content in ferulic acid, whereas the caffeic acid level is the lowest. Regarding the flavonoids, there are many quantitative differences between the samples: one extract lacking the rutoside and two of them having low apigenin-7-glucoside contents.

Fatal overdose of 2,4-dichlorophenoxyacetic acid (2,4-D).

PubMed

Keller, T; Skopp, G; Wu, M; Aderjan, R

1994-03-01

An ingestion of an unknown quantity of U 46 D-Fluid (500 g dichlorophenoxyacetic acid/l) in a suicide is described. Although 2,4-dichlorophenoxyacetic acid (2,4 D) is widely used as a herbicide, intoxications are relatively rare. Quantitation of 2,4-D was performed by diethyl ether extraction from acidified samples (viscera) or by deproteinization (blood, plasma) with methanol before HPLC analysis. Postmortem concentrations of 2,4-D in body fluids and tissues are given. The proposed method resulted in a rapid procedure most useful in cases of deliberate poisoning with phenoxyacetic herbicides.

A simple quantitative approach for the determination of long and medium chain lipids in bio-relevant matrices by high performance liquid chromatography with refractive index detection.

PubMed

Lee, Kathy Wai Yu; Porter, Christopher J H; Boyd, Ben J

2013-09-01

There is increasing attention in the literature towards understanding the behaviour of lipid-based drug formulations under digestion conditions using in vitro and in vivo methods. This necessitates a convenient method for quantitation of lipids and lipid digestion products. In this study, a simple and accessible method for the separation and quantitative determination of typical formulation and digested lipids using high performance liquid chromatography coupled to refractive index detection (HPLC-RI) is described. Long and medium chain lipids were separated and quantified in a biological matrix (gastrointestinal content) without derivatisation using HPLC-RI on C18 and C8 columns, respectively. The intra- and inter-assay accuracy was between 92% and 106%, and the assays were precise to within a coefficient of variation of less than 10% over the range of 0.1-2 mg/mL for both long and medium chain lipids. This method is also shown to be suitable for quantifying the lipolysis products collected from the gastrointestinal tract in the course of in vivo lipid digestion studies.

A high-throughput platform for low-volume high-temperature/pressure sealed vessel solvent extractions.

PubMed

Damm, Markus; Kappe, C Oliver

2011-11-30

A high-throughput platform for performing parallel solvent extractions in sealed HPLC/GC vials inside a microwave reactor is described. The system consist of a strongly microwave-absorbing silicon carbide plate with 20 cylindrical wells of appropriate dimensions to be fitted with standard HPLC/GC autosampler vials serving as extraction vessels. Due to the possibility of heating up to four heating platforms simultaneously (80 vials), efficient parallel analytical-scale solvent extractions can be performed using volumes of 0.5-1.5 mL at a maximum temperature/pressure limit of 200°C/20 bar. Since the extraction and subsequent analysis by either gas chromatography or liquid chromatography coupled with mass detection (GC-MS or LC-MS) is performed directly from the autosampler vial, errors caused by sample transfer can be minimized. The platform was evaluated for the extraction and quantification of caffeine from commercial coffee powders assessing different solvent types, extraction temperatures and times. For example, 141±11 μg caffeine (5 mg coffee powder) were extracted during a single extraction cycle using methanol as extraction solvent, whereas only 90±11 were obtained performing the extraction in methylene chloride, applying the same reaction conditions (90°C, 10 min). In multiple extraction experiments a total of ~150 μg caffeine was extracted from 5 mg commercial coffee powder. In addition to the quantitative caffeine determination, a comparative qualitative analysis of the liquid phase coffee extracts and the headspace volatiles was performed, placing special emphasis on headspace analysis using solid-phase microextraction (SPME) techniques. The miniaturized parallel extraction technique introduced herein allows solvent extractions to be performed at significantly expanded temperature/pressure limits and shortened extraction times, using standard HPLC autosampler vials as reaction vessels. Remarkable differences regarding peak pattern and main peaks were observed when low-temperature extraction (60°C) and high-temperature extraction (160°C) are compared prior to headspace-SPME-GC-MS performed in the same HPLC/GC vials. Copyright © 2011 Elsevier B.V. All rights reserved.

The use of capillary electrophoresis as part of a specificity testing strategy for mitoguazone dihydrochloride HPLC methods.

PubMed

Thomson, C E; Gray, M R; Baxter, M P

1997-05-01

Capillary electrophoresis (CE) has been used as part of a validation experiment designed to prove the specificity of high performance liquid chromatography (HPLC) methods used for analysis of mitoguazone dihydrochloride drug substance. Data regarding accuracy, precision and sensitivity of the CE methods are presented as well as a comparison of results obtained from CE, HPLC and thin-layer chromatography (TLC) analysis of samples stressed under a variety of conditions. It was concluded that, not only were the HPLC methods being investigated specific, but that CE could potentially be used to replace HPLC for the routine assay of mitoguazone dihydrochloride.

Demonstration and Evaluation of Solid Phase Microextraction for the Assessment of Bioavailability and Contaminant Mobility. ESTCP Cost and Performance Report

DTIC Science & Technology

2012-08-01

subsequent chemical analysis (into acetonitrile for high-performance liquid chromatography [ HPLC ] analysis or hexane for gas chromatography [GC... analysis ) is rapid and complete. In this work, PAHs were analyzed by Waters 2795 HPLC with fluorescent detection (USEPA Method 8310) and PCBs were...detection limits by direct water injection versus SPME with PDMS and coefficient of variation and correlation coefficient for SPME. Analysis by HPLC

Quantitative analysis of phenolic metabolites from different parts of Angelica keiskei by HPLC-ESI MS/MS and their xanthine oxidase inhibition.

PubMed

Kim, Dae Wook; Curtis-Long, Marcus J; Yuk, Heung Joo; Wang, Yan; Song, Yeong Hun; Jeong, Seong Hun; Park, Ki Hun

2014-06-15

Angelica keiskei is used as popular functional food stuff. However, quantitative analysis of this plant's metabolites has not yet been disclosed. The principal phenolic compounds (1-16) within A. keiskei were isolated, enabling us to quantify the metabolites within different parts of the plant. The specific quantification of metabolites (1-16) was accomplished by multiple reaction monitoring (MRM) using a quadruple tandem mass spectrometer. The limit of detection and limit of quantitation were calculated as 0.4-44 μg/kg and 1.5-148 μg/kg, respectively. Abundance and composition of these metabolites varied significantly across different parts of plant. For example, the abundance of chalcones (12-16) decreased as follows: root bark (10.51 mg/g)>stems (8.52 mg/g)>leaves (2.63 mg/g)>root cores (1.44 mg/g). The chalcones were found to be responsible for the xanthine oxidase (XO) inhibition shown by this plant. The most potent inhibitor, xanthoangelol inhibited XO with an IC50 of 8.5 μM. Chalcones (12-16) exhibited mixed-type inhibition characteristics. Copyright © 2013 Elsevier Ltd. All rights reserved.

Quantitation in chiral capillary electrophoresis: theoretical and practical considerations.

PubMed

D'Hulst, A; Verbeke, N

1994-06-01

Capillary electrophoresis (CE) represents a decisive step forward in stereoselective analysis. The present paper deals with the theoretical aspects of the quantitation of peak separation in chiral CE. Because peak shape is very different in CE with respect to high performance liquid chromatography (HPLC), the resolution factor Rs, commonly used to describe the extent of separation between enantiomers as well as unrelated compounds, is demonstrated to be of limited value for the assessment of chiral separations in CE. Instead, the conjunct use of a relative chiral separation factor (RCS) and the percent chiral separation (% CS) is advocated. An array of examples is given to illustrate this. The practical aspects of method development using maltodextrins--which have been proposed previously as a major innovation in chiral selectors applicable in CE--are documented with the stereoselective analysis of coumarinic anticoagulant drugs. The possibilities of quantitation using CE were explored under two extreme conditions. Using ibuprofen, it has been demonstrated that enantiomeric excess determinations are possible down to a 1% level of optical contamination and stereoselective determinations are still possible with a good precision near the detection limit, increasing sample load by very long injection times. The theoretical aspects of this possibility are addressed in the discussion.

Aqueous Reversed-Phase HPLC/FT-IR Using Diffuse Reflectance Detections

NASA Astrophysics Data System (ADS)

Kalasinsky, Victor F.; Pai, T. H.; Kenton, R. C.; Kalasinsky, Kathryn S.

1989-12-01

Solvent-elimination HPLC/FT-IR has become a viable combination of two important techniques, and we have been developing a system which is adaptable to both normal and reversed-phase liquid chromatography. The interface involves the deposition of HPLC eluites onto a KCI-laden train with subsequent analysis via diffuse reflectance spectroscopy, and with minor modifications, the system can be used with microbore and analytical columns. With aqueous solvents, the water is converted to methanol and acetone in a post-column reaction with 2,2-dimethoxypropane before the eluites are deposited. A number of different samples have been used to demonstrate the interface and its flexibility. Steroids, analgesics, and other pharmaceutical preparations have been separated with reverse-phase solvents and identified by their infrared spectra. For some of the compounds studied, different infrared spectra of a given compound have been found to exhibit intensity variations, which arise from different crystalline states. The differences can be concentration dependent and may be useful in obtaining semi-quantitative information from the infrared spectra. Applications involving both gradient elution and isocratic separations have been successful. The former provides the same advantages for HPLC/FT-IR as one finds in conventional HPLC. More recent work has been applied to the use of buffers such as those frequently used in bioanalytical separations. In trying to simplify the post-column reaction with water, we have immobilized dehydration reagents onto silica particles and packed these materials into a column which is inserted in-line after the analytical column. Of the reagents utilized to date, 3,3-dimethoxypropyltrimethoxysilane has been found to perform most efficiently. It has advantages over the simpler reagents because it can be regenerated in the reaction column. Results and the efficiency of the dehydration process and its relation to the type of reagent and its coverage will be discussed.

Characterization of E 471 food emulsifiers by high-performance thin-layer chromatography-fluorescence detection.

PubMed

Oellig, Claudia; Brändle, Klara; Schwack, Wolfgang

2018-07-13

Mono- and diacylglycerol (MAG and DAG) emulsifiers, also known as food additive E 471, are widely used to adjust techno-functional properties in various foods. Besides MAGs and DAGs, E 471 emulsifiers additionally comprise different amounts of triacylglycerols (TAGs) and free fatty acids (FFAs). MAGs, DAGs, TAGs and FFAs are generally determined by high-performance liquid chromatography (HPLC) or gas chromatography (GC) coupled to mass selective detection, analyzing the individual representatives of the lipid classes. In this work we present a rapid and sensitive method for the determination of MAGs, DAGs, TAGs and FFAs in E 471 emulsifiers by high-performance thin-layer chromatography with fluorescence detection (HPTLC-FLD), including a response factor system for quantitation. Samples were simply dissolved and diluted with t-butyl methyl ether before a two-fold development was performed on primuline pre-impregnated LiChrospher silica gel plates with diethyl ether and n-pentane/n-hexane/diethyl ether (52:20:28, v/v/v) as the mobile phases to 18 and 75 mm, respectively. For quantitation, the plate was scanned in the fluorescence mode at UV 366/>400 nm, when the cumulative signal for each lipid class was used. Calibration was done with 1,2-distearin and amounts of lipid classes were calculated with response factors and expressed as monostearin, distearin, tristearin and stearic acid. Limits of detection and quantitation were 1 and 4 ng/zone, respectively, for 1,2-distearin. Thus, the HPTLC-FLD approach represents a simple, rapid and convenient screening alternative to HPLC and GC analysis of the individual compounds. Visual detection additionally enables an easy characterization and the direct comparison of emulsifiers through the lipid class pattern, when utilized as a fingerprint. Copyright © 2018 Elsevier B.V. All rights reserved.

Development and validation of a RP-HPLC method for the quantitation of tofacitinib in rat plasma and its application to a pharmacokinetic study.

PubMed

S, Vijay Kumar; Dhiman, Vinay; Giri, Kalpesh Kumar; Sharma, Kuldeep; Zainuddin, Mohd; Mullangi, Ramesh

2015-09-01

A novel, simple, specific, sensitive and reproducible high-performance liquid chromatography (HPLC) assay method has been developed and validated for the estimation of tofacitinib in rat plasma. The bioanalytical procedure involves extraction of tofacitinib and itraconazole (internal standard, IS) from rat plasma with a simple liquid-liquid extraction process. The chromatographic analysis was performed on a Waters Alliance system using a gradient mobile phase conditions at a flow rate of 1.0 mL/min and C18 column maintained at 40 ± 1 °C. The eluate was monitored using an UV detector set at 287 nm. Tofacitinib and IS eluted at 6.5 and 8.3 min, respectively and the total run time was 10 min. Method validation was performed as per US Food and Drug Administration guidelines and the results met the acceptance criteria. The calibration curve was linear over a concentration range of 182-5035 ng/mL (r(2) = 0.995). The intra- and inter-day precisions were in the range of 1.41-11.2 and 3.66-8.81%, respectively, in rat plasma. The validated HPLC method was successfully applied to a pharmacokinetic study in rats. Copyright © 2015 John Wiley & Sons, Ltd.

Quantitative analysis of cellular proteome alterations in human influenza A virus-infected mammalian cell lines.

PubMed

Vester, Diana; Rapp, Erdmann; Gade, Dörte; Genzel, Yvonne; Reichl, Udo

2009-06-01

Over the last years virus-host cell interactions were investigated in numerous studies. Viral strategies for evasion of innate immune response, inhibition of cellular protein synthesis and permission of viral RNA and protein production were disclosed. With quantitative proteome technology, comprehensive studies concerning the impact of viruses on the cellular machinery of their host cells at protein level are possible. Therefore, 2-D DIGE and nanoHPLC-nanoESI-MS/MS analysis were used to qualitatively and quantitatively determine the dynamic cellular proteome responses of two mammalian cell lines to human influenza A virus infection. A cell line used for vaccine production (MDCK) was compared with a human lung carcinoma cell line (A549) as a reference model. Analyzing 2-D gels of the proteomes of uninfected and influenza-infected host cells, 16 quantitatively altered protein spots (at least +/-1.7-fold change in relative abundance, p<0.001) were identified for both cell lines. Most significant changes were found for keratins, major components of the cytoskeleton system, and for Mx proteins, interferon-induced key components of the host cell defense. Time series analysis of infection processes allowed the identification of further proteins that are described to be involved in protein synthesis, signal transduction and apoptosis events. Most likely, these proteins are required for supporting functions during influenza viral life cycle or host cell stress response. Quantitative proteome-wide profiling of virus infection can provide insights into complexity and dynamics of virus-host cell interactions and may accelerate antiviral research and support optimization of vaccine manufacturing processes.

High-performance liquid chromatography-tandem mass spectrometry as a reference for analysis of tacrolimus to assess two immunoassays in patients with liver and renal transplants.

PubMed

Salm, P; Taylor, P J; Clark, A; Balderson, G A; Grygotis, A; Norris, R L; Lynch, S V; Shaw, L M; Pond, S M

1997-12-01

The accuracy and imprecision of three assays used for therapeutic monitoring of tacrolimus were tested using blood-containing weighed-in amounts of the drug, an enzyme-linked immunosorbent assay (ELISA), a microparticle enzyme immunoassay (MEIA I), and a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS2) assay. Accuracy was acceptable for the HPLC-MS2 assay at all concentrations tested (< 10% deviation) and for the ELISA at 1.0 and 4.0 microg/l. Accuracy was not acceptable for the ELISA at 15.0 and 50.0 microg/l or for the MEIA I at all concentrations tested. Imprecision was acceptable for the HPLC-MS2 assay at all concentrations tested (coefficient of variation < 10%), for the ELISA at 15.0 and 50.0 microg/l, and for the MEIA I at 15.0 and 50.0 microg/l. Imprecision was not acceptable for the ELISA at 1.0 and 4.0 microg/l or for the MEIA I at 1.0 and 4.0 microg/l. This assessment with weighed-in amounts of tacrolimus verified the HPLC-MS2 assay as a reference method. The performance of the two immunoassays with HPLC-MS2 was then compared in the clinical setting using blood from patients with liver (n = 30) and renal (n = 37) transplants. In the liver transplant group (127 samples), the range of tacrolimus concentrations measured by HPLC-MS2, ELISA, and MEIA I was 1.9 to 31.8, 2.1 to 35.0, and less than 0.1 to 36.5 mg/l, respectively. In the renal transplant group (129 samples), the ranges were 1.7 to 26.1, 1.9 to 24.4, and 0.9 to 28.5 microg/l, respectively. Compared with the HPLC-MS2, the ELISA had minimal bias (0.1 to 0.2 microg/l) but unacceptable variability in values (SD > 13%). The MEIA I had unacceptable bias (1.7-1.8 microg/l) and variability (SD > 23%). These data indicated that neither the ELISA nor MEIA I is interchangeable with HPLC-MS2. Moreover, in view of the current trend to reduce the therapeutic dose of tacrolimus, quantitative results using the MEIA I would not be obtainable during therapeutic drug monitoring in some patients in whom effective therapeutic concentrations can be less than 5.0 microg/l.

Forensic Drug Identification, Confirmation, and Quantification Using Fully Integrated Gas Chromatography with Fourier Transform Infrared and Mass Spectrometric Detection (GC-FT-IR-MS).

PubMed

Lanzarotta, Adam; Lorenz, Lisa; Voelker, Sarah; Falconer, Travis M; Batson, JaCinta S

2018-05-01

This manuscript is a continuation of a recent study that described the use of fully integrated gas chromatography with direct deposition Fourier transform infrared detection and mass spectrometric detection (GC-FT-IR-MS) to identify and confirm the presence of sibutramine and AB-FUBINACA. The purpose of the current study was to employ the GC-FT-IR portion of the same instrument to quantify these compounds, thereby demonstrating the ability to identify, confirm, and quantify drug substances using a single GC-FT-IR-MS unit. The performance of the instrument was evaluated by comparing quantitative analytical figures of merit to those measured using an established, widely employed method for quantifying drug substances, high performance liquid chromatography with ultraviolet detection (HPLC-UV). The results demonstrated that GC-FT-IR was outperformed by HPLC-UV with regard to sensitivity, precision, and linear dynamic range (LDR). However, sibutramine and AB-FUBINACA concentrations measured using GC-FT-IR were not significantly different at the 95% confidence interval compared to those measured using HPLC-UV, which demonstrates promise for using GC-FT-IR as a semi-quantitative tool at the very least. The most significant advantage of GC-FT-IR compared to HPLC-UV is selectivity; a higher level of confidence regarding the identity of the analyte being quantified is achieved using GC-FT-IR. Additional advantages of using a single GC-FT-IR-MS instrument for identification, confirmation, and quantification are efficiency, increased sample throughput, decreased consumption of laboratory resources (solvents, chemicals, consumables, etc.), and thus cost.

Development of a Fourier transform infrared spectroscopy coupled to UV-Visible analysis technique for aminosides and glycopeptides quantitation in antibiotic locks.

PubMed

Sayet, G; Sinegre, M; Ben Reguiga, M

2014-01-01

Antibiotic Lock technique maintains catheters' sterility in high-risk patients with long-term parenteral nutrition. In our institution, vancomycin, teicoplanin, amikacin and gentamicin locks are prepared in the pharmaceutical department. In order to insure patient safety and to comply to regulatory requirements, antibiotic locks are submitted to qualitative and quantitative assays prior to their release. The aim of this study was to develop an alternative quantitation technique for each of these 4 antibiotics, using a Fourier transform infrared (FTIR) coupled to UV-Visible spectroscopy and to compare results to HPLC or Immunochemistry assays. Prevalidation studies permitted to assess spectroscopic conditions used for antibiotic locks quantitation: FTIR/UV combinations were used for amikacin (1091-1115cm(-1) and 208-224nm), vancomycin (1222-1240cm(-1) and 276-280nm), and teicoplanin (1226-1230cm(-1) and 278-282nm). Gentamicin was quantified with FTIR only (1045-1169cm(-1) and 2715-2850cm(-1)) due to interferences in UV domain of parabens, preservatives present in the commercial brand used to prepare locks. For all AL, the method was linear (R(2)=0.996 to 0.999), accurate, repeatable (intraday RSD%: from 2.9 to 7.1% and inter-days RSD%: 2.9 to 5.1%) and precise. Compared to the reference methods, the FTIR/UV method appeared tightly correlated (Pearson factor: 97.4 to 99.9%) and did not show significant difference in recovery determinations. We developed a new simple reliable analysis technique for antibiotics quantitation in locks using an original association of FTIR and UV analysis, allowing a short time analysis to identify and quantify the studied antibiotics. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Comparative HPLC/ESI-MS and HPLC/DAD study of different populations of cultivated, wild and commercial Gentiana lutea L.

PubMed

Mustafa, Ahmed M; Caprioli, Giovanni; Ricciutelli, Massimo; Maggi, Filippo; Marín, Rosa; Vittori, Sauro; Sagratini, Gianni

2015-05-01

The root of Gentiana lutea L., famous for its bitter properties, is often used in alcoholic bitter beverages, food products and traditional medicine to stimulate the appetite and improve digestion. This study presents a new, fast, and accurate HPLC method using HPLC/ESI-MS and HPLC/DAD for simultaneous analysis of iridoids (loganic acid), secoiridoids (gentiopicroside, sweroside, swertiamarin, amarogentin) and xanthones (isogentisin) in different populations of G.lutea L., cultivated in the Monti Sibillini National Park, obtained wild there, or purchased commercially. Comparison of HPLC/ESI-MS and HPLC/DAD indicated that HPLC/ESI-MS is more sensitive, reliable and selective. Analysis of twenty samples showed that gentiopicroside is the most dominant compound (1.85-3.97%), followed by loganic acid (0.11-1.30%), isogentisin (0.03-0.48%), sweroside (0.05-0.35%), swertiamarin (0.08-0.30%), and amarogentin (0.01-0.07%). The results confirmed the high quality of the G.lutea cultivated in the Monti Sibillini National Park. Copyright © 2014 Elsevier Ltd. All rights reserved.

Quantitative Determination of Catechin as Chemical Marker in Pediatric Polyherbal Syrup by HPLC/DAD.

PubMed

Sheikh, Zeeshan A; Siddiqui, Zafar A; Naveed, Safila; Usmanghani, Khan

2016-09-01

Vivabon syrup is a balanced composition of dietary ingredients of phytopharmaceutical nature for maintaining the physique, vigor, vitality and balanced growth of children. The herbal ingredients of pediatric syrup are rich in bioflavonoid, proteins, vitamins, glycosides and trace elements. Vivabon is formulated with herbal drugs such as Phoenix sylvestris, Emblica officinalis, Withania somnifera, Centella asiatica, Amomum subulatum, Zingiber officinalis, Trigonella foenum-graecum, Centaurea behen and Piper longum Catechins are flavan-3-ols that are found widely in the medicinal herbs and are utilized for anti-inflammatory, cardio protective, hepato-protective, neural protection and other biological activities. In general, the dietary intake of flavonoids has been regarded traditionally as beneficial for body growth. Standardization of Vivabon syrup dosage form using HPLC/DAD has been developed for quantitative estimation of Catechin as a chemical marker. The method was validated as per ICH guidelines. Validation studies demonstrated that the developed HPLC method is quite distinct, reproducible as well as quick and fast. The relatively high recovery and low comparable standard deviation confirm the suitability of the developed method for the determination of Catechin in syrup. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Quantitative and Qualitative Characterization of Gentiana rigescens Franch (Gentianaceae) on Different Parts and Cultivations Years by HPLC and FTIR Spectroscopy

PubMed Central

Qi, Lu-Ming; Zuo, Zhi-Tian

2017-01-01

Gentiana rigescens Franch (Gentianaceae) is a famous medicinal plant for treatments of rheumatism, convulsion, and jaundice. Comprehensive investigation of different parts and cultivation years of this plant has not yet been conducted. This study presents the quantitative and qualitative characterization of iridoid glycosides from G. rigescens performed by HPLC and FTIR spectroscopy techniques. The accumulations of loganic acid, swertiamarin, gentiopicroside, and sweroside were determined. Results indicated that their content and distribution in different parts and cultivation years exhibit great variations. Gentiopicroside was identified as the most abundant compound among iridoid glycosides and its highest level was observed in the root of 2-year-old plant. With respect to qualitative variation of metabolic profile, the 1800–800 cm−1 band of FTIR spectra successfully discriminated different parts and cultivation years with the aid of PLS-DA. In addition, combined with PLSR, the feasibility of FTIR spectroscopy for determination of gentiopicroside was investigated by selecting characteristic wavelengths (1800–800 cm−1), which presented a good performance with a residual predictive deviation (RPD) of 3.646. Our results suggested that HPLC and FTIR techniques can complement each other and could be simultaneously applied for comparing and analyzing different parts and cultivation years of G. rigescens. PMID:28656121

Automated on-line renewable solid-phase extraction-liquid chromatography exploiting multisyringe flow injection-bead injection lab-on-valve analysis.

PubMed

Quintana, José Benito; Miró, Manuel; Estela, José Manuel; Cerdà, Víctor

2006-04-15

In this paper, the third generation of flow injection analysis, also named the lab-on-valve (LOV) approach, is proposed for the first time as a front end to high-performance liquid chromatography (HPLC) for on-line solid-phase extraction (SPE) sample processing by exploiting the bead injection (BI) concept. The proposed microanalytical system based on discontinuous programmable flow features automated packing (and withdrawal after single use) of a small amount of sorbent (<5 mg) into the microconduits of the flow network and quantitative elution of sorbed species into a narrow band (150 microL of 95% MeOH). The hyphenation of multisyringe flow injection analysis (MSFIA) with BI-LOV prior to HPLC analysis is utilized for on-line postextraction treatment to ensure chemical compatibility between the eluate medium and the initial HPLC gradient conditions. This circumvents the band-broadening effect commonly observed in conventional on-line SPE-based sample processors due to the low eluting strength of the mobile phase. The potential of the novel MSFI-BI-LOV hyphenation for on-line handling of complex environmental and biological samples prior to reversed-phase chromatographic separations was assessed for the expeditious determination of five acidic pharmaceutical residues (viz., ketoprofen, naproxen, bezafibrate, diclofenac, and ibuprofen) and one metabolite (viz., salicylic acid) in surface water, urban wastewater, and urine. To this end, the copolymeric divinylbenzene-co-n-vinylpyrrolidone beads (Oasis HLB) were utilized as renewable sorptive entities in the micromachined unit. The automated analytical method features relative recovery percentages of >88%, limits of detection within the range 0.02-0.67 ng mL(-1), and coefficients of variation <11% for the column renewable mode and gives rise to a drastic reduction in operation costs ( approximately 25-fold) as compared to on-line column switching systems.

A method for fast determination of psoralens in oral solutions of phytomedicines using liquid chromatography.

PubMed

Pires, Adriana Elias; Honda, Neli Kiko; Cardoso, Cláudia Andréa Lima

2004-10-29

A method for sample preparation and analysis by high performance liquid chromatography with UV detection (HPLC-UV) has been developed for routine analysis of psoralen and bergapten, photosensitizing compounds, in oral solutions of phytomedicines employed in Brazil for some illnesses. The linearity, accuracy, the inter- and intra-day precision of the procedure were evaluated. Calibration curves for psoralen and bergapten were linear in the range of 1.0-600.0 microg ml(-1) and 1.0-400.0 microg ml(-1) respectively. The recoveries of the psoralens in the oral solutions analysed were 94.43-99.97%. The percentage coefficient of variation (CV) of the quantitative analysis of the psoralens in the products analysis was within 5%. In inter-equipment study was employed gas chromatography-flame ionization (CG-FID) detection.

High-Performance Liquid Chromatography (HPLC) Quantification of Liposome-Delivered Doxorubicin in Arthritic Joints of Collagen-Induced Arthritis Rats.

PubMed

Niu, Hongqing; Xu, Menghua; Li, Shuangtian; Chen, Junwei; Luo, Jing; Zhao, Xiangcong; Gao, Chong; Li, Xiaofeng

2017-04-14

BACKGROUND Neoangiogenesis occurring in inflamed articular synovium in early rheumatoid arthritis (RA) is characterized by enhanced vascular permeability that allows nanoparticle agents, including liposomes, to deliver encapsulated drugs to arthritic joints and subsequently improve therapeutic efficacy and reduce adverse effects. However, the targeting distribution of liposomes in arthritic joints during RA has not been quantitatively demonstrated. We performed this study to evaluate the targeting distribution of PEGylated doxorubicin liposomes in the arthritic joints of collagen-induced arthritis (CIA) rats by high-performance liquid chromatography (HPLC). MATERIAL AND METHODS Two doxorubicin formulations were administered to CIA rats via tail intravenous injection at a single dose (50 mg/m²). CIA rats were sacrificed and the tissues of the inflamed ankle joints were collected. The content of doxorubicin in the arthritic joints was analyzed by a validated and reproducible HPLC method. A two-way ANOVA for 2×5 factorial design was used for statistical analysis. RESULTS The developed HPLC method was sensitive, precise, and reproducible. The method was successfully applied to quantify doxorubicin content in arthritic tissues. At each time point (6, 12, 24, 48, and 72 h), doxorubicin content in the arthritic joints of the doxorubicin liposome group (DOX-LIP group) was higher than in the free doxorubicin group (DOX group) (P<0.05). In the DOX-LIP group, doxorubicin levels in the arthritic joints increased gradually and significantly in the interval of 6-72 h post-administration. CONCLUSIONS PEGylated doxorubicin liposomes were targeted to, accumulated, and retained in the arthritic joints of CIA rats. The present study indicates that liposome encapsulation increases the therapeutic efficacy of antirheumatic drugs, presenting a promising therapeutic strategy for RA.

Quantitation of iothalamate in urine and plasma using liquid chromatography electrospray tandem mass spectrometry (HPLC-ESI-MS/MS).

PubMed

Molinaro, Ross J; Ritchie, James C

2010-01-01

The following chapter describes a method to measure iothalamate in plasma and urine samples using high performance liquid chromatography combined with electrospray positive ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Methanol and water are spiked with the internal standard (IS) iohexol. Iothalamate is isolated from plasma after IS spiked methanol extraction and from urine by IS spiked water addition and quick-spin filtration. The plasma extractions are dried under a stream of nitrogen. The residue is reconstituted in ammonium acetate-formic acid-water. The reconstituted plasma and filtered urine are injected into the HPLC-ESI-MS/MS. Iothalamate and iohexol show similar retention times in plasma and urine. Quantification of iothalamate in the samples is made by multiple reaction monitoring using the hydrogen adduct mass transitions, from a five-point calibration curve.

Evaluation and routine application of the novel restricted-access precolumn packing material Alkyl-Diol Silica: coupled-column high-performance liquid chromatographic analysis of the photoreactive drug 8-methoxypsoralen in plasma.

PubMed

Vielhauer, S; Rudolphi, A; Boos, K S; Seidel, D

1995-04-21

A fully automated coupled-column HPLC method for on-line sample processing and determination of the photoreactive drug 8-methoxypsoralen (8-MOP) in plasma has been developed. The method is based on the novel internal-surface reversed-phase precolumn packing materials Alkyl-Diol Silica (ADS). This new family of restricted-access materials has a hydrophilic, electroneutral outer particle surface and a hydrophobic internal pore surface. The supports tolerate the direct and repetitive injection of proteinaceous fluids such as plasma and allow a classical C18-, C8- or C4-reversed-phase partitioning at the internal (pore) surface. The total protein load, i.e. the lifetime of the precolumn used in this study (C8-Alkyl-Diol Silica, 25 microns, 25 x 4 mm I.D.), exceeds more than 100 ml of plasma. 8-MOP was detected by its native fluorescence (excitation 312 nm, emission 540 nm). Validation of the method revealed a quantitative and matrix-independent recovery (99.5-101.3% measured at five concentrations between 21.3 and 625.2 ng of 8-MOP per milliliter of plasma), linearity over a wide range of 8-MOP concentrations (1.2-3070 ng of 8-MOP/ml, r = 0.999), low limits of detection (0.39 ng of 8-MOP/ml) and quantitation (0.79 ng of 8-MOP/ml) and a high between-run (C.V. 1.47%, n = 10) and within-run (C.V. 1.33%, n = 10) reproducibility. This paper introduces coupled-column HPLC as a suitable method for on-site analysis of drug plasma profiles (bedside-monitoring).

Simultaneous determination of gatifloxacin and ambroxol hydrochloride from tablet dosage form using reversed-phase high performance liquid chromatography.

PubMed

Shahed, Mirza; Nanda, Rabindra; Dehghan, Muhammad Hassan; Nasreen, Huda; Feroz, Shaikh

2008-05-01

A reversed-phase high performance liquid chromatography (HPLC) method was developed, validated, and used for the quantitative determination of gatifloxacin (GA) and ambroxol hydrochloride (AM), from its tablet dosage form. Chromatographic separation was performed on a HiQ Sil C18 column (250 mm x 4.6 mm, 5 microm), with a mobile phase comprising of a mixture of 0.01 mol/L potassium dihydrogen orthophosphate buffer and acetonitrile (70 : 30, v/v), and pH adjusted to 3 with orthophosphoric acid, at a flow rate of 1 mL/min, with detection at 247 nm. Separation was completed in less than 10 min. As per International Conference on Harmonisation (ICH) guidelines the method was validated for linearity, accuracy, precision, limit of quantitation, limit of detection, and robustness. Linearity of GA was found to be in the range of 10 -60 microg/mL and that for AM was found to be 5 - 30 microg/mL. The correlation coefficients were 0.999 6 and 0.999 3 for GA and AM respectively. The results of the tablet analysis (n = 5) were found to be 99.94% with +/- 0.25% standard deviation (SD) and 99.98% with +/- 0.36% SD for GA and AM respectively. Percent recovery of GA was found to be 99.92% - 100.02% and that of AM was 99.86% - 100.16%. The assay experiment shows that the method is free from interference of excipients. This demonstrates that the developed HPLC method is simple, linear, precise, and accurate, and can be conveniently adopted for the routine quality control analysis of the tablet.

Determination of the antileukemic drug mitoguazone and seven other closely related bis(amidinohydrazones) in human blood serum by high-performance liquid chromatography.

PubMed

Koskinen, M; Elo, H; Lukkari, P; Riekkola, M L

1996-10-11

A reversed-phase (C18) HPLC method with diode-array detection was developed for the separation and determination of methylglyoxal bis(amidinohydrazone) (mitoguazone) and seven closely related aliphatic analogs thereof, namely the bis(amidinohydrazones) of glyoxal, dimethylglyoxal, ethylmethylglyoxal, methylpropylglyoxal, butylmethylglyoxal, diethylglyoxal and dipropylglyoxal. The mobile phase consisted of a non-linear binary gradient of methanol and 0.03 M aqueous sodium acetate buffer (pH 4.3). Good separation of the eight congeners was achieved. On increasing the methanol content of the eluent, the bis(amidinohydrazones) eluted in the order of increasing number of carbon atoms in the side-chains. The method was also applied to the quantitative analysis of the compounds in aqueous solution and, combined with ultrafiltration, for the separation of the eight congeners in spiked human blood serum. A separate simplified method for the quantitative determination of each of the compounds in spiked human blood serum samples was also developed. The methods developed made for the first time possible the simultaneous HPLC analysis of more than one bis(amidinohydrazones). The results obtained indicate that the bis(amidinohydrazones) studied obviously have a distinct tendency to form ion associates with acetate ions and probably also other carboxylate ions in aqueous solution. This aspect may be of biochemical significance, especially concerning the intracellular binding of the compounds. Each one of the compounds studied invariably gave rise to one peak only, this result supporting the theory that the conventional synthesis of each of the compounds gives rise to one geometrical isomer only. This result is completely in agreement with the results of previous proton and carbon NMR spectroscopic as well as X-ray diffraction studies.

High perfomance liquid chromatography fingerprint analysis for quality control of brotowali (Tinospora crispa)

NASA Astrophysics Data System (ADS)

Syarifah, V. B.; Rafi, M.; Wahyuni, W. T.

2017-05-01

Brotowali (Tinospora crispa) is widely used in Indonesia as ingredient of herbal medicine formulation. To ensure the quality, safety, and efficacy of herbal medicine products, its chemical constituents should be continuously evaluated. High performance liquid chromatography (HPLC) fingerprint is one of powerful technique for this quality control process. In this study, HPLC fingerprint analysis method was developed for quality control of brotowali. HPLC analysis was performed in C18 column and detection was performed using photodiode array detector. The optimum mobile phase for brotowali fingerprint was acetonitrile (ACN) and 0.1% formic acid in gradient elution mode at a flow rate of 1 mL/min. The number of peaks detected in HPLC fingerprint of brotowali was 32 peaks and 23 peaks for stems and leaves, respectively. Berberine as marker compound was detected at retention time of 20.525 minutes. Evaluation of analytical performance including precision, reproducibility, and stability prove that this HPLC fingerprint analysis was reliable and could be applied for quality control of brotowali.

Multielemental speciation analysis by advanced hyphenated technique - HPLC/ICP-MS: A review.

PubMed

Marcinkowska, Monika; Barałkiewicz, Danuta

2016-12-01

Speciation analysis has become an invaluable tool in human health risk assessment, environmental monitoring or food quality control. Another step is to develop reliable multielemental speciation methodologies, to reduce costs, waste and time needed for the analysis. Separation and detection of species of several elements in a single analytical run can be accomplished by high performance liquid chromatography hyphenated to inductively coupled plasma mass spectrometry (HPLC/ICP-MS). Our review assembles articles concerning multielemental speciation determination of: As, Se, Cr, Sb, I, Br, Pb, Hg, V, Mo, Te, Tl, Cd and W in environmental, biological, food and clinical samples analyzed with HPLC/ICP-MS. It addresses the procedures in terms of following issues: sample collection and pretreatment, selection of optimal conditions for elements species separation by HPLC and determination using ICP-MS as well as metrological approach. The presented work is the first review article concerning multielemental speciation analysis by advanced hyphenated technique HPLC/ICP-MS. Copyright © 2016 Elsevier B.V. All rights reserved.

Hydrogen sulfide measurement using sulfide dibimane: critical evaluation with electrospray ion trap mass spectrometry

PubMed Central

Shen, Xinggui; Chakraborty, Sourav; Dugas, Tammy R; Kevil, Christopher G

2015-01-01

Accurate measurement of hydrogen sulfide bioavailability remains a technical challenge due to numerous issues involving sample processing, detection methods used, and actual biochemical products measured. Our group and others have reported that reverse phase HPLC detection of sulfide dibimane (SDB) product from the reaction of H2S/HS− with monobromobimane allows for analytical detection of hydrogen sulfide bioavailability in free and other biochemical forms. However, it remains unclear whether possible interfering contaminants may contribute to HPLC SDB peak readings that may result in inaccurate measurements of bioavailable sulfide. In this study, we critically compared hydrogen sulfide dependent SDB detection using reverse phase HPLC (RP-HPLC) versus quantitative SRM electrospray ionization mass spectrometry (ESI/MS) to obtain greater clarity into the validity of the reverse phase HPLC method for analytical measurement of hydrogen sulfide. Using an LCQ-deca ion-trap mass spectrometer, SDB was identified by ESI/MS positive ion mode, and quantified by selected reaction monitoring (SRM) using hydrocortisone as an internal standard. Collision induced dissociation (CID) parameters were optimized at MS2 level for SDB and hydrocortisone. ESI/MS detection of SDB standard was found to be a log order more sensitive than RP-HPLC with a lower limit of 0.25 nM. Direct comparison of tissue and plasma SDB levels using RP-HPLC and ESI/MS methods revealed comparable sulfide levels in plasma, aorta, heart, lung and brain. Together, these data confirm the use of SDB as valid indicator of H2S bioavailability and highlights differences between analytical detection methods. PMID:24932544

An Approach Based on HPLC-Fingerprint and Chemometrics to Quality Consistency Evaluation of Matricaria chamomilla L. Commercial Samples

PubMed Central

Viapiana, Agnieszka; Struck-Lewicka, Wiktoria; Konieczynski, Pawel; Wesolowski, Marek; Kaliszan, Roman

2016-01-01

Chamomile has been used as an herbal medication since ancient times and is still popular because it contains various bioactive phytochemicals that could provide therapeutic effects. In this study, a simple and reliable HPLC method was developed to evaluate the quality consistency of nineteen chamomile samples through establishing a chromatographic fingerprint, quantification of phenolic compounds and determination of antioxidant activity. For fingerprint analysis, 12 peaks were selected as the common peaks to evaluate the similarities of commercial samples of chamomile obtained from different manufacturers. A similarity analysis was performed to assess the similarity/dissimilarity of chamomile samples where values varied from 0.868 to 0.990 what indicating that samples from different manufacturers were consistent. Additionally, simultaneous quantification of five phenolic acids (gallic, caffeic, syringic, p-coumaric, ferulic) and four flavonoids (rutin, myricetin, quercetin and keampferol) was performed to interpret the quality consistency. In quantitative analysis, the nine individual phenolic compounds showed good regression (r > 0.9975). Inter- and intra-day precisions for all analyzed compounds expressed as relative standard deviation (CV) ranged from 0.05% to 3.12%. Since flavonoids and other polyphenols are commonly recognized as natural antioxidants, the antioxidant activity of chamomile samples was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing/antioxidant power (FRAP) assay. Correlation analysis was used to assess the relationship between antioxidant activity and phenolic composition, and multivariate analysis (PCA and HCA) were applied to distinguish chamomile samples. Results shown in the study indicate high similarity of chamomile samples among them, widely spread in the market and commonly used by people as infusions or teas, as well as that there were no statistically significant differences among them, which in turn is a proof of high quality of commercially available samples of chamomile. The study indicated that the combination of chromatographic fingerprint and quantitative analysis can be readily utilized as a quality consistency method for chamomile and related medicinal preparations. Moreover, the applied strategy seems to be the most promising for the assessment of the investigated plant material. PMID:27818668

Evolution of Quantitative Measures in NMR: Quantum Mechanical qHNMR Advances Chemical Standardization of a Red Clover (Trifolium pratense) Extract

PubMed Central

2017-01-01

Chemical standardization, along with morphological and DNA analysis ensures the authenticity and advances the integrity evaluation of botanical preparations. Achievement of a more comprehensive, metabolomic standardization requires simultaneous quantitation of multiple marker compounds. Employing quantitative 1H NMR (qHNMR), this study determined the total isoflavone content (TIfCo; 34.5–36.5% w/w) via multimarker standardization and assessed the stability of a 10-year-old isoflavone-enriched red clover extract (RCE). Eleven markers (nine isoflavones, two flavonols) were targeted simultaneously, and outcomes were compared with LC-based standardization. Two advanced quantitative measures in qHNMR were applied to derive quantities from complex and/or overlapping resonances: a quantum mechanical (QM) method (QM-qHNMR) that employs 1H iterative full spin analysis, and a non-QM method that uses linear peak fitting algorithms (PF-qHNMR). A 10 min UHPLC-UV method provided auxiliary orthogonal quantitation. This is the first systematic evaluation of QM and non-QM deconvolution as qHNMR quantitation measures. It demonstrates that QM-qHNMR can account successfully for the complexity of 1H NMR spectra of individual analytes and how QM-qHNMR can be built for mixtures such as botanical extracts. The contents of the main bioactive markers were in good agreement with earlier HPLC-UV results, demonstrating the chemical stability of the RCE. QM-qHNMR advances chemical standardization by its inherent QM accuracy and the use of universal calibrants, avoiding the impractical need for identical reference materials. PMID:28067513

The use of dissolvable layered double hydroxide components in an in situ solid-phase extraction for chromatographic determination of tetracyclines in water and milk samples.

PubMed

Phiroonsoontorn, Nattaphorn; Sansuk, Sira; Santaladchaiyakit, Yanawath; Srijaranai, Supalax

2017-10-13

This research presents a simple and green in situ solid phase extraction (is-SPE) combined with high-performance liquid chromatography (HPLC) for the simultaneous analysis of tetracyclines (TCs) including tetracycline, oxytetracycline, and chlortetracycline. In is-SPE, TCs were efficiently extracted through the precipitation formation of dissolvable layered double hydroxides (LDHs) by mixing the LDH components such as magnesium and aluminum ions (both in metal chloride salts) thoroughly in an alkaline sample solution. After the centrifugation, the precipitate was completely dissolved with trifluoroacetic acid to release the enriched TCs, and then analyzed by HPLC. Under optimized conditions, this method gave good enrichment factors (EFs) of 41-93 with low limits of detection (LODs) of 0.7-6μg/L and limits of quantitation (LOQs) of 3-15μg/L. Also, the proposed method was successfully applied for the determination of TCs in water and milk samples with the recoveries ranging from 81.7-108.1% for water and 55.7-88.7% for milk. Copyright © 2017 Elsevier B.V. All rights reserved.

High-throughput immunomagnetic scavenging technique for quantitative analysis of live VX nerve agent in water, hamburger, and soil matrixes.

PubMed

Knaack, Jennifer S; Zhou, Yingtao; Abney, Carter W; Prezioso, Samantha M; Magnuson, Matthew; Evans, Ronald; Jakubowski, Edward M; Hardy, Katelyn; Johnson, Rudolph C

2012-11-20

We have developed a novel immunomagnetic scavenging technique for extracting cholinesterase inhibitors from aqueous matrixes using biological targeting and antibody-based extraction. The technique was characterized using the organophosphorus nerve agent VX. The limit of detection for VX in high-performance liquid chromatography (HPLC)-grade water, defined as the lowest calibrator concentration, was 25 pg/mL in a small, 500 μL sample. The method was characterized over the course of 22 sample sets containing calibrators, blanks, and quality control samples. Method precision, expressed as the mean relative standard deviation, was less than 9.2% for all calibrators. Quality control sample accuracy was 102% and 100% of the mean for VX spiked into HPLC-grade water at concentrations of 2.0 and 0.25 ng/mL, respectively. This method successfully was applied to aqueous extracts from soil, hamburger, and finished tap water spiked with VX. Recovery was 65%, 81%, and 100% from these matrixes, respectively. Biologically based extractions of organophosphorus compounds represent a new technique for sample extraction that provides an increase in extraction specificity and sensitivity.

[Study on arsenic speciation changes in crude and processed traditional Chinese medicines by HPLC-ICP-MS].

PubMed

Jin, Peng-fei; Wu, Xue-jun; Zou, Ding; Kuang, Yong-mei; Hu, Xin; Jiang, Wen-qing; Sun, Chun-hua

2011-03-01

A HPLC-ICP-MS method for simultaneous determination of As(III), As(V), MMA and DMA in traditional Chinese medicines (TCMs) was established, and the contents of As(III), As(V), MMA and DMA in a TCM with high total arsenic content (Cordyceps) and 5 crude and processed TCMs (Radix Astragali, Radix et Rhizoma Rhei, Radix Scutellariae, Radix Polygoni Multiflori and Radix Rehmanniae) were determined and analyzed. The method validation indicated that the correlative coefficients (r) for all speciations were bigger than 0.9984; the limits of quantitation (LOQ) were from 0.8 to 1.0 microg x L(-1); the reproducibility and stability were satisfactory with all RSDs less than 10%; the spiked recoveries ranged from 82.40% to 119.5%. The results of samples analysis showed that the inorganic arsenic (As(III) and As(V)) was the dominating speciation in the tested TCMs; MMA and DMA were not found in all plant resourced TCMs, but MMA was found in Cordyceps; all the tested TCMs indicated a content increasing of inorganic arsenic after processing.

A high-performance liquid chromatography-based radiometric assay for acyl-CoA:alcohol transacylase from jojoba.

PubMed

Garver, W S; Kemp, J D; Kuehn, G D

1992-12-01

Acyl-CoA:alcohol transacylase catalyzes the final step in the biosynthesis of storage liquid wax esters from acyl-CoA fatty acids and fatty alcohols in a limited number of microbes, algae, and Simmondsia chinensis Link (jojoba). An improved and automated method of enzyme assay for this catalyst from cotyledons of jojoba is described. The assay method uses reversed-phase C18 high performance liquid chromatography (HPLC) to separate the labeled C30:1 liquid wax product, [14C]-dodecanyl-octadecenoate, from the unreacted substrate, [14C]octadecenoyl-CoA (oleyl-CoA), and other components produced from enzymes present in the crude homogenate of jojoba cotyledons, including [14C]-octadecenoic acid (oleic acid) and [14C]octadecenol (oleyol). Methods are also described for microscale chemical synthesis in one vessel of 14C-radiolabeled substrates and products for the transacylase. These labeled reagents are required to confirm the HPLC separations of reaction products. The radioactive components are quantitated using an on-line flow-through scintillation detector enabling sensitive and precise analysis of the reaction products.

HPLC and chemometrics-assisted UV-spectroscopy methods for the simultaneous determination of ambroxol and doxycycline in capsule

NASA Astrophysics Data System (ADS)

Hadad, Ghada M.; El-Gindy, Alaa; Mahmoud, Waleed M. M.

2008-08-01

High-performance liquid chromatography (HPLC) and multivariate spectrophotometric methods are described for the simultaneous determination of ambroxol hydrochloride (AM) and doxycycline (DX) in combined pharmaceutical capsules. The chromatographic separation was achieved on reversed-phase C 18 analytical column with a mobile phase consisting of a mixture of 20 mM potassium dihydrogen phosphate, pH 6-acetonitrile in ratio of (1:1, v/v) and UV detection at 245 nm. Also, the resolution has been accomplished by using numerical spectrophotometric methods as classical least squares (CLS), principal component regression (PCR) and partial least squares (PLS-1) applied to the UV spectra of the mixture and graphical spectrophotometric method as first derivative of the ratio spectra ( 1DD) method. Analytical figures of merit (FOM), such as sensitivity, selectivity, analytical sensitivity, limit of quantitation and limit of detection were determined for CLS, PLS-1 and PCR methods. The proposed methods were validated and successfully applied for the analysis of pharmaceutical formulation and laboratory-prepared mixtures containing the two component combination.

HPLC and chemometrics-assisted UV-spectroscopy methods for the simultaneous determination of ambroxol and doxycycline in capsule.

PubMed

Hadad, Ghada M; El-Gindy, Alaa; Mahmoud, Waleed M M

2008-08-01

High-performance liquid chromatography (HPLC) and multivariate spectrophotometric methods are described for the simultaneous determination of ambroxol hydrochloride (AM) and doxycycline (DX) in combined pharmaceutical capsules. The chromatographic separation was achieved on reversed-phase C(18) analytical column with a mobile phase consisting of a mixture of 20mM potassium dihydrogen phosphate, pH 6-acetonitrile in ratio of (1:1, v/v) and UV detection at 245 nm. Also, the resolution has been accomplished by using numerical spectrophotometric methods as classical least squares (CLS), principal component regression (PCR) and partial least squares (PLS-1) applied to the UV spectra of the mixture and graphical spectrophotometric method as first derivative of the ratio spectra ((1)DD) method. Analytical figures of merit (FOM), such as sensitivity, selectivity, analytical sensitivity, limit of quantitation and limit of detection were determined for CLS, PLS-1 and PCR methods. The proposed methods were validated and successfully applied for the analysis of pharmaceutical formulation and laboratory-prepared mixtures containing the two component combination.

Phytochemical composition of fractions isolated from ten Salvia species by supercritical carbon dioxide and pressurized liquid extraction methods.

PubMed

Šulniūtė, Vaida; Pukalskas, Audrius; Venskutonis, Petras Rimantas

2017-06-01

Ten Salvia species, S. amplexicaulis, S. austriaca, S. forsskaolii S. glutinosa, S. nemorosa, S. officinalis, S. pratensis, S. sclarea, S. stepposa and S. verticillata were fractionated using supercritical carbon dioxide and pressurized liquid (ethanol and water) extractions. Fifteen phytochemicals were identified using commercial standards (some other compounds were identified tentatively), 11 of them were quantified by ultra high pressure chromatography (UPLC) with quadruple and time-of-flight mass spectrometry (Q/TOF, TQ-S). Lipophilic CO 2 extracts were rich in tocopherols (2.36-10.07mg/g), while rosmarinic acid was dominating compound (up to 30mg/g) in ethanolic extracts. Apigenin-7-O-β-d-glucuronide, caffeic and carnosic acids were quantitatively important phytochemicals in the majority other Salvia spp. Antioxidatively active constituents were determined by using on-line high-performance liquid chromatography (HPLC) analysis combined with 2,2'-diphenyl-1-picrylhydrazyl (DPPH) assay (HPLC-DPPH). Development of high pressure isolation process and comprehensive characterisation of phytochemicals in Salvia spp. may serve for their wider applications in functional foods and nutraceuticals. Copyright © 2016 Elsevier Ltd. All rights reserved.

Development and Validation of High Performance Liquid Chromatography Method for Determination Atorvastatin in Tablet

NASA Astrophysics Data System (ADS)

Yugatama, A.; Rohmani, S.; Dewangga, A.

2018-03-01

Atorvastatin is the primary choice for dyslipidemia treatment. Due to patent expiration of atorvastatin, the pharmaceutical industry makes copy of the drug. Therefore, the development methods for tablet quality tests involving atorvastatin concentration on tablets needs to be performed. The purpose of this research was to develop and validate the simple atorvastatin tablet analytical method by HPLC. HPLC system used in this experiment consisted of column Cosmosil C18 (150 x 4,6 mm, 5 µm) as the stationary reverse phase chomatography, a mixture of methanol-water at pH 3 (80:20 v/v) as the mobile phase, flow rate of 1 mL/min, and UV detector at wavelength of 245 nm. Validation methods were including: selectivity, linearity, accuracy, precision, limit of detection (LOD), and limit of quantitation (LOQ). The results of this study indicate that the developed method had good validation including selectivity, linearity, accuracy, precision, LOD, and LOQ for analysis of atorvastatin tablet content. LOD and LOQ were 0.2 and 0.7 ng/mL, and the linearity range were 20 - 120 ng/mL.

Development and Validation of an Enzymatic Method To Determine Stevioside Content from Stevia rebaudiana.

PubMed

Udompaisarn, Somsiri; Arthan, Dumrongkiet; Somana, Jamorn

2017-04-19

An enzymatic method for specific determination of stevioside content was established. Recombinant β-glucosidase BT_3567 (rBT_3567) from Bacteroides thetaiotaomicron HB-13 exhibited selective hydrolysis of stevioside at β-1,2-glycosidic bond to yield rubusoside and glucose. Coupling of this enzyme with glucose oxidase and peroxidase allowed for quantitation of stevioside content in Stevia samples by using a colorimetric-based approach. The series of reactions for stevioside determination can be completed within 1 h at 37 °C. Stevioside determination using the enzymatic assay strongly correlated with results obtained from HPLC quantitation (r 2 = 0.9629, n = 16). The percentages of coefficient variation (CV) of within day (n = 12) and between days (n = 12) assays were lower than 5%, and accuracy ranges were 95-105%. This analysis demonstrates that the enzymatic method developed in this study is specific, easy to perform, accurate, and yields reproducible results.

Quantitative Chromatographic Determination of Dissolved Elemental Sulfur in the Non-aqueous Electrolyte for Lithium-Sulfur Batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, Dong; Yang, Xiao-Qing; Zhang, Xuran

A fast and reliable analytical method is reported for the quantitative determination of dissolved elemental sulfur in non-aqueous electrolytes for Li-S batteries. By using high performance liquid chromatography with a UV detector, the solubility of S in 12 different pure solvents and in 22 different electrolytes was determined. It was found that the solubility of elemental sulfur is dependent on the Lewis basicity, the polarity of solvents and the salt concentration in the electrolytes. In addition, the S content in the electrolyte recovered from a discharged Li-S battery was successfully determined by the proposed HPLC/UV method. Thus, the feasibility ofmore » the method to the online analysis for a Li-S battery is demonstrated. Interestingly, the S was found super-saturated in the electrolyte recovered from a discharged Li-S cell.« less

Quantitative Chromatographic Determination of Dissolved Elemental Sulfur in the Non-aqueous Electrolyte for Lithium-Sulfur Batteries

DOE PAGES

Zheng, Dong; Yang, Xiao-Qing; Zhang, Xuran; ...

2014-12-02

A fast and reliable analytical method is reported for the quantitative determination of dissolved elemental sulfur in non-aqueous electrolytes for Li-S batteries. By using high performance liquid chromatography with a UV detector, the solubility of S in 12 different pure solvents and in 22 different electrolytes was determined. It was found that the solubility of elemental sulfur is dependent on the Lewis basicity, the polarity of solvents and the salt concentration in the electrolytes. In addition, the S content in the electrolyte recovered from a discharged Li-S battery was successfully determined by the proposed HPLC/UV method. Thus, the feasibility ofmore » the method to the online analysis for a Li-S battery is demonstrated. Interestingly, the S was found super-saturated in the electrolyte recovered from a discharged Li-S cell.« less

ComplexQuant: high-throughput computational pipeline for the global quantitative analysis of endogenous soluble protein complexes using high resolution protein HPLC and precision label-free LC/MS/MS.

PubMed

Wan, Cuihong; Liu, Jian; Fong, Vincent; Lugowski, Andrew; Stoilova, Snejana; Bethune-Waddell, Dylan; Borgeson, Blake; Havugimana, Pierre C; Marcotte, Edward M; Emili, Andrew

2013-04-09

The experimental isolation and characterization of stable multi-protein complexes are essential to understanding the molecular systems biology of a cell. To this end, we have developed a high-throughput proteomic platform for the systematic identification of native protein complexes based on extensive fractionation of soluble protein extracts by multi-bed ion exchange high performance liquid chromatography (IEX-HPLC) combined with exhaustive label-free LC/MS/MS shotgun profiling. To support these studies, we have built a companion data analysis software pipeline, termed ComplexQuant. Proteins present in the hundreds of fractions typically collected per experiment are first identified by exhaustively interrogating MS/MS spectra using multiple database search engines within an integrative probabilistic framework, while accounting for possible post-translation modifications. Protein abundance is then measured across the fractions based on normalized total spectral counts and precursor ion intensities using a dedicated tool, PepQuant. This analysis allows co-complex membership to be inferred based on the similarity of extracted protein co-elution profiles. Each computational step has been optimized for processing large-scale biochemical fractionation datasets, and the reliability of the integrated pipeline has been benchmarked extensively. This article is part of a Special Issue entitled: From protein structures to clinical applications. Copyright © 2012 Elsevier B.V. All rights reserved.

A simultaneous screening and quantitative method for the multiresidue analysis of pesticides in spices using ultra-high performance liquid chromatography-high resolution (Orbitrap) mass spectrometry.

PubMed

Goon, Arnab; Khan, Zareen; Oulkar, Dasharath; Shinde, Raviraj; Gaikwad, Suresh; Banerjee, Kaushik

2018-01-12

A novel screening and quantitation method is reported for non-target multiresidue analysis of pesticides using ultra-HPLC-quadrupole-Orbitrap mass spectrometry in spice matrices, including black pepper, cardamom, chili, coriander, cumin, and turmeric. The method involved sequential full-scan (resolution = 70,000), and variable data independent acquisition (vDIA) with nine consecutive fragmentation events (resolution = 17,500). Samples were extracted by the QuEChERS method. The introduction of an SPE-based clean-up step through hydrophilic-lipophilic-balance (HLB) cartridges proved advantageous in minimizing the false negatives. For coriander, cumin, chili, and cardamom, the screening detection limit was largely at 2 ng/g, while it was 5 ng/g for black pepper, and turmeric. When the method was quantitatively validated for 199 pesticides, the limit of quantification (LOQ) was mostly at 10 ng/g (excluding black pepper, and turmeric with LOQ = 20 ng/g) with recoveries within 70-120%, and precision-RSDs <20%. Furthermore, the method allowed the identification of suspected non-target analytes through retrospective search of the accurate mass of the compound-specific precursor and product ions. Compared to LC-MS/MS, the quantitative performance of this Orbitrap-MS method had agreements in residue values between 78-100%. Copyright © 2017 Elsevier B.V. All rights reserved.

Quality evaluation of Yin Chen Hao Tang extract based on fingerprint chromatogram and simultaneous determination of five bioactive constituents.

PubMed

Wang, Xijun; Lv, Haitao; Sun, Hui; Jiang, Xingang; Wu, Zeming; Sun, Wenjun; Wang, Ping; Liu, Lian; Bi, Kaishun

2008-01-01

A completely validated method based on HPLC coupled with photodiode array detector (HPLC-UV) was described for evaluating and controlling quality of Yin Chen Hao Tang extract (YCHTE). First, HPLC-UV fingerprint chromatogram of YCHTE was established for preliminarily elucidating amount and chromatographic trajectory of chemical constituents in YCHTE. Second, for the first time, five mainly bioactive constituents in YCHTE were simultaneously determined based on fingerprint chromatogram for furthermore controlling the quality of YCHTE quantitatively. The developed method was applied to analyze 12 batches of YCHTE samples which consisted of herbal drugs from different places of production, showed acceptable linearity, intraday (RSD <5%), interday precision (RSD <4.80%), and accuracy (RSD <2.80%). As a result, fingerprint chromatogram determined 15 representative general fingerprint peaks, and the fingerprint chromatogram resemblances are all better than 0.9996. The contents of five analytes in different batches of YCHTE samples do not indicate significant difference. So, it is concluded that the developed HPLC-UV method is a more fully validated and complete method for evaluating and controlling the quality of YCHTE.

Novel liquid chromatographic assay for the low-level determination of apomorphine in plasma.

PubMed

Priston, M J; Sewell, G J

1996-05-31

A novel HPLC assay which is rapid, reproducible and sensitive has been developed for the analysis of apomorphine in plasma. The assay incorporates boldine as an internal standard, and uses solid-phase extraction on C18 mini-columns for sample clean-up and concentration, so enabling quantitation of apomorphine at 500 pg/ml using fluorescence detection (lambda(ex) 270 nm, lambda(em) 450 nm). The HPLC assay comprised a 25 cm-long Techopak C18 column and a mobile phase of (0.25 M sodium dihydrogen phosphate plus 0.25% heptane sulphonic acid, to pH 3.3 with orthophosphoric acid) containing 30% (v/v) methanol and 0.003% (w/v) EDTA, run at a flow-rate of 1.5 ml/min. Calibration plots prepared in plasma were linear over the range 1-30 ng/ml, (limit of quantitation (LOQ) = 490 pg/ml) with R.S.D. of 0.05% and R.E. of 5.0% at the level of 1 ng/ml. Preliminary pharmacokinetic data from two patients given apomorphine by 12 h subcutaneous infusion (patient A dose = 35 mg and patient B dose = 141 mg) showed apomorphine elimination from plasma to fit a two-compartment model, with initial half-lives of 8.2 and 46.6 min, elimination half-lives of 76.4 and 166.5 min and area under the plasma concentration-time curve (AUC) values of 236 and 405 ng h/ml, respectively.

Electrodialytic in-line preconcentration for ionic solute analysis.

PubMed

Ohira, Shin-Ichi; Yamasaki, Takayuki; Koda, Takumi; Kodama, Yuko; Toda, Kei

2018-04-01

Preconcentration is an effective way to improve analytical sensitivity. Many types of methods are used for enrichment of ionic solute analytes. However, current methods are batchwise and include procedures such as trapping and elution. In this manuscript, we propose in-line electrodialytic enrichment of ionic solutes. The method can enrich ionic solutes within seconds by quantitative transfer of analytes from the sample solution to the acceptor solution under an electric field. Because of quantitative ion transfer, the enrichment factor (the ratio of the concentration in the sample and to that in the obtained acceptor solution) only depends on the flow rate ratio of the sample solution to the acceptor solution. The ratios of the concentrations and flow rates are equal for ratios up to 70, 20, and 70 for the tested ionic solutes of inorganic cations, inorganic anions, and heavy metal ions, respectively. The sensitivity of ionic solute determinations is also improved based on the enrichment factor. The method can also simultaneously achieve matrix isolation and enrichment. The method was successively applied to determine the concentrations of trace amounts of chloroacetic acids in tap water. The regulated concentration levels cannot be determined by conventional high-performance liquid chromatography with ultraviolet detection (HPLC-UV) without enrichment. However, enrichment with the present method is effective for determination of tap water quality by improving the limits of detection of HPLC-UV. The standard addition test with real tap water samples shows good recoveries (94.9-109.6%). Copyright © 2017 Elsevier B.V. All rights reserved.

High Performance Liquid Chromatography-Diode Array Detector Method for the Simultaneous Determination of Five Compounds in the Pulp and Seed of Sea Buckthorn

PubMed Central

Zhao, Lu; Wen, E; Upur, Halmuart; Tian, Shuge

2017-01-01

Context: Sea buckthorn (Hippophae rhamnoides L.) as a traditional Chinese medicinal plant has various uses in Xinjiang. Objective: A reversed-phase rapid-resolution liquid-chromatography method with diode array detector was developed for simultaneous determination of protocatechuic acid, rutin, quercetin, kaempferol, and isorhamnetin in the pulp and seed of sea buckthorn, a widely used traditional Chinese medicine for promoting metabolism and treating scurvy and other diseases. Settings and design: Compounds were separated on an Agilent ZORBAX SB-C18 column (4.6 mm × 250 mm, 5 μm; USA) with gradient elution using methanol and 0.4% phosphoric acid (v/v) at 1.0 mL/min. Detection wavelength was set at 280 nm. Materials and Methods: The fruits of wild sea buckthorn were collected from Wushi County in Aksu, Xinjiang Province. Statistical performances: The RSD of precision test of the five compounds were in the range of 0.60-2.22%, and the average recoveries ranged from 97.36% to 101.19%. Good linearity between specific chromatographic peak and component qualities were observed in the investigated ranges for all the analytes (R2 > 0.9997). Results: The proposed method was successfully applied to determine the levels of five active components in sea buckthorn samples from Aksu in Xinjiang. Conclusions: The proposed method is simple, fast, sensitive, accurate, and suitable for quantitative assessment of the pulp and seed of sea buckthorn. SUMMARY Quantitative analysis method of protocatechuic acid, rutin, quercetin, kaempferol, and isorhamnetin in the extract of sea buckthorn pulp and seed is developed by high-performance liquid chromatography (HPLC) diode array detection.This method is simple and accurate; has strong specificity, good precision, and high recovery rate; and provides a reliable basis for further development of the substances in the pulp and seed of sea buckthorn.The method is widely used for content determination of active ingredients or physiologically active components in traditional Chinese medicine and its preparation Abbreviation used: PR: protocatechuic acid, RU: rutin, QU: quercetin, KA: kaempferol, IS: isorhamnetin, HPLC: high-performance liquid chromatography, HPLC-DAD: high performance liquid chromatographydiode array detector, LOD: linearity and limit of detection, LOQ: limit of quantitation, RSD: relative standard deviation PMID:28216897

Current HPLC Methods for Assay of Nano Drug Delivery Systems.

PubMed

Tekkeli, Serife Evrim Kepekci; Kiziltas, Mustafa Volkan

2017-01-01

In nano drug formulations the mechanism of release is a critical process to recognize controlled and targeted drug delivery systems. In order to gain high bioavailability and specificity from the drug to reach its therapeutic goal, the active substance must be loaded into the nanoparticles efficiently. Therefore, the amount in biological fluids or tissues and the remaining amount in nano carriers are very important parameters to understand the potential of the nano drug delivery systems. For this aim, suitable and validated quantitation methods are required to determine released drug concentrations from nano pharmaceutical formulations. HPLC (High Performance Liquid Chromatography) is one of the most common techniques used for determination of released drug content out of nano drug formulations, in different physical conditions, over different periods of time. Since there are many types of HPLC methods depending on detector and column types, it is a challenge for the researchers to choose a suitable method that is simple, fast and validated HPLC techniques for their nano drug delivery systems. This review's goal is to compare HPLC methods that are currently used in different nano drug delivery systems in order to provide detailed and useful information for researchers. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Characterisation of nucleosides and nucleobases in Mactra veneriformis by high performance liquid chromatography coupled with diode array detector-mass spectrometry (HPLC-DAD-MS).

PubMed

Liu, Rui; Ji, Jing; Wang, Lingchong; Chen, Shiyong; Guo, Sheng; Wu, Hao

2012-11-15

Mactra veneriformis has been used as sea food and traditional Chinese medicine (TCM) for thousands of years in China. In the present study, a high performance liquid chromatograph coupled with photodiode array detector and electrospray ionisation-mass spectrometer (HPLC-DAD-ESI-MS) method was established for detection of the nucleosides and nucleobases in M. veneriformis from four aquaticultural area of Jiangsu during different harvest time of one year. The validated method was successfully applied to identifying 10 nucleosides and nucleobases in 48 M. veneriformis samples. Quantitative analysis showed that nucleosides and nucleobases are rich in all M. veneriformis samples. However, their contents vary in different areas and harvest times. Principal component analysis (PCA) was used to classify the 48 samples based on the contents of the nucleosides and nucleobases. As a result, the samples could be mainly clustered into four groups, which was similar as aquaticultural areas classification. Based on the results, present method might be applicable for the quality control of M. veneriformis, or even other marine shellfish aquiculture and their products, and the quality of M. veneriformis might be more related with aquaticultural areas. Copyright © 2012 Elsevier Ltd. All rights reserved.

A survey of liquid chromatographic-mass spectrometric analysis of mercapturic acid biomarkers in occupational and environmental exposure monitoring.

PubMed

Mathias, Patricia I; B'Hymer, Clayton

2014-08-01

High-performance liquid chromatography/mass spectrometry (HPLC/MS) is sensitive and specific for targeted quantitative analysis and is readily utilized for small molecules from biological matrices. This brief review describes recent selected HPLC/MS methods for the determination of urinary mercapturic acids (mercapturates) which are useful as biomarkers in characterizing human exposure to electrophilic industrial chemicals in occupational and environmental studies. Electrophilic compounds owing to their reactivity are used in chemical and industrial processes. They are present in industrial emissions, are combustion products of fossil fuels, and are components in tobacco smoke. Their presence in both the industrial and general environments are of concern for human and environmental health. Urinary mercapturates which are the products of metabolic detoxification of reactive chemicals provide a non-invasive tool to investigate human exposure to electrophilic toxicants. Selected recent mercapturate quantification methods are summarized and specific cases are presented. The biological formation of mercapturates is introduced and their use as biomarkers of metabolic processing of electrophilic compounds is discussed. Also, the use of liquid chromatography/tandem mass spectrometry in simultaneous determinations of the mercapturates of multiple parent compounds in a single determination is considered, as well as future trends and limitations in this area of research. Published by Elsevier B.V.

[A new HPLC procedure for cyclamate in food with pre-chromatographic derivatization].

PubMed

Schwedt, G; Hauck, M

1988-08-01

A high-pressure liquid chromatography (HPLC) procedure for the detection of cyclamate in liquid and solid samples is presented, which depends on oxidation and the reaction of cyclohexylamine with o-phthaldialdehyde to form a condensation product. The results of the HPLC analysis, using an RP-C 18 separation system with UV detection at 242 nm are reported. Contents, from 2 to 400 mg/l, can be detected in less than 2 h (HPLC analysis within 20 min) with relative standard deviations of 4%. Only for cucumber infusions were incomplete recoveries of 68% obtained.

[Quantitative method for simultaneous assay of four coumarins with one marker in Fraxini Cortex].

PubMed

Feng, Weihong; Wang, Zhimin; Zhang, Qiwei; Liu, Limei; Wang, Jinyu; Yang, Fei

2011-07-01

To establish a new quantitative method for simultaneous determination of multi-coumarins in Fraxini Cortex by using one chemical reference substance, and validate its feasibilities. The new quality evaluation method, quantitative analysis of multi-components by singer-marker (QAMS), was established and validated with Fraxini Cortex. Four main coumarins were selected as analytes to evaluate the quality and their relative correlation factors (RCF) were determined by HPLC-DAD. Within the linear range, the values of RCF at 340 nm of aesculin to asculetin, fraxin and fraxetin were 1.771, 0.799, 1.409, respectively. And the contents of aesculin in samples of Fraxini Cortex were authentically determined by the external standard method, and the contents of the three other coumarins were calculated by their RCF. The contents of these four coumarins in all samples were also determined by the external standard method. Within a certain range, the RCF had a good reproducibility (RSD 2.5%-3.9%). Significant differences were not observed between the quantitative results of two methods. It is feasible and suitable to evaluate the quality of Fraxini Cortex and its Yinpian by QAMS.

Variations in chemical fingerprints and major flavonoid contents from the leaves of thirty-one accessions of Hibiscus sabdariffa L.

PubMed

Wang, Jin; Cao, Xianshuang; Ferchaud, Vanessa; Qi, Yadong; Jiang, Hao; Tang, Feng; Yue, Yongde; Chin, Kit L

2016-06-01

The leaves of Hibiscus sabdariffa L. have been used as traditional folk medicines for treating high blood pressure and fever. There are many accessions of H. sabdariffa L. throughout the world. To assess the chemical variations of 31 different accessions of H. sabdariffa L., fingerprinting analysis and quantitation of major flavonoids were performed by high-performance liquid chromatography (HPLC). The HPLC method was validated for linearity, sensitivity, precision, repeatability and accuracy. A quadrupole-time-of-flight mass spectrometry (Q-TOF-MS) was applied for the characterization of major compounds. A total of 9 compounds were identified, including 6 flavonoids and 3 phenolic acids. In the fingerprint analysis, similarity analysis (SA) and principal component analysis (PCA) were used to differentiate the 31 accessions of H. sabdariffa L. Based on the results of PCA and SA, the samples No. 15 and 19 appeared much different from the main group. The total content of five flavonoids varied greatly among different accessions, ranging from 3.35 to 23.30 mg/g. Rutin was found to be the dominant compound and the content of rutin could contribute to chemical variations among different accessions. This study was helpful to understand the chemical variations between different accessions of H. sabdariffa L., which could be used for quality control. © 2015 The Authors Biomedical Chromatography Published by John Wiley & Sons Ltd. © 2015 The Authors Biomedical Chromatography Published by John Wiley & Sons Ltd.

Determination of blood cyanide by HPLC-MS.

PubMed

Tracqui, A; Raul, J S; Géraut, A; Berthelon, L; Ludes, B

2002-04-01

An original high-performance liquid chromatographic-mass spectrometric (HPLC-MS) procedure was developed for the determination of cyanide (CN) in whole blood. After the addition of K13C15N as internal standard, blood was placed in a microdiffusion device, the inner well of which was filled with a mixture of taurine (50mM in water)/naphthalene-2,3-dicarboxaldehyde (NDA, 10mM in methanol)/methanol/ concentrated (approximately 20%) ammonia solution (25:25:45:5, v/v). Concentrated H2SO4 was added to the blood sample, and the microdiffusion chamber was sealed. After 30 min of gentle agitation, 2 microL of the contents of the inner vial were pipetted and directly injected onto a NovaPak C18 HPLC column. Separation was performed by a gradient of acetonitrile in 2mM NH4COOH, pH 3.0 buffer (35-80% in 10 min). Detection was done with a Perkin-Elmer Sciex API-100 mass analyzer with an ionspray interface, operated in the negative ionization mode. MS data were collected as either TIC or SIM at m/z (299 + 191) and (301 + 193) for the derivatives formed with CN and 13C15N, respectively. Inspired by previous works dealing with the complexation of CN by NDA + taurine to form a 1-cyano [f] benzoisoindole derivative analyzed by HPLC-fluorimetry, this method appears simple, rapid, and extremely specific. Limits of detection and quantitation for blood CN are 5 and 15 ng/mL, respectively. The use of 13C15N as internal standard allows the quantitation of CN with elegance and accuracy in comparison with previously reported methods.

Composition of Indigo naturalis.

PubMed

Plitzko, Inken; Mohn, Tobias; Sedlacek, Natalie; Hamburger, Matthias

2009-06-01

A proposal for a European Pharmacopoeia monograph concerning Indigo naturalis has recently been published, whereby the indigo (1) and indirubin (2) content should be determined by HPLC-UV. This method was tested, but problems were seen with the dosage of indigo due to poor solubility. A quantitative assay for indigo based on (1)H-NMR was developed as an alternative. The HPLC and qNMR assays were compared with eight Indigo naturalis samples. The HPLC assay consistently gave much lower indigo concentrations because solubility was the limiting factor in sample preparation. In one sample, sucrose was identified by (1)H-NMR as an organic additive. Simple wet chemistry assays for undeclared additives such as sugars and starch were tested with artificially spiked Indigo naturalis samples to establish their limits of detection, and sulfate ash determinations were carried out in view of a better assessment of Indigo naturalis in a future European monograph.

Characterization of nonstarch polysaccharides content from different edible organs of some vegetables, determined by GC and HPLC: comparative study.

PubMed

Villanueva-Suárez, M J; Redondo-Cuenca, A; Rodríguez-Sevilla, M D; de las Heras Martínez, M

2003-09-24

Content and composition of dietary fiber as nonstarch polysaccharides (NSP) was determined in vegetables belonging to different types of edible organs, using GC and HPLC. Samples analyzed were subterranean organs (radish and leek), leaves (celery, swiss chard, and lettuce), stalks (celery, swiss chard, and asparagus), inflorescence (broccoli), and fruits (tomato, green pepper, and marrow). The results indicate that though the monomeric profile is similar in all these samples quantitative differences were found for neutral sugars and uronic acids among samples of the same type of vegetal organ. The NSP values determined using CG method were in good agreement with HPLC method (R(2) = 0.9005). However, arabinose, mannose, and galactose plus rhamnose are more influenced by the analytical method used than the rest of the monomers in nearly all the samples analyzed. Final values of NSP depend on the method used in celery stalks, broccoli, and green pepper.

The effect of re-dissolution solvents and HPLC columns on the analysis of mycosporine-like amino acids in the eulittoral macroalgae Prasiola crispa and Porphyra umbilicalis

NASA Astrophysics Data System (ADS)

Karsten, Ulf; Escoubeyrou, Karine; Charles, François

2009-09-01

Many macroalgal species that are regularly exposed to high solar radiation such as the eulittoral green alga Prasiola crispa and the red alga Porphyra umbilicalis synthesize and accumulate high concentrations of mycosporine-like amino acids (MAAs) as UV-sunscreen compounds. These substances are typically extracted with a widely used standard protocol following quantification by various high performance liquid chromatography (HPLC) techniques. However, further preparation steps prior to HPLC analysis as well as different HPLC column types have not been systematically checked regarding separation quality and reproducibility. Therefore pure methanol, distilled water and HPLC eluent were evaluated as re-dissolution solvent for dried Prasiola and Porphyra extracts, which were subsequently analyzed on three reversed-phase C8 and C18 HPLC columns. The data indicate that distilled water and the HPLC eluent gave almost identical peak patterns and MAA contents on the C8 and C18 columns. In contrast, the application of the widely used methanol led to double peaks or even the loss of specific peaks as well as to a strong decline in total MAA amounts ranging from about 35% of the maximum in P. crispa to 80% of the maximum in P. umbilicalis. Consequently, methanol should be avoided as re-dissolution solvent for the HPLC sample preparation. An improved protocol for the MAA analysis in macroalgae in combination with a reliable C18 column is suggested.

HPLC-Orbitrap analysis for identification of organic molecules in complex material

NASA Astrophysics Data System (ADS)

Gautier, T.; Schmitz-Afonso, I.; Carrasco, N.; Touboul, D.; Szopa, C.; Buch, A.; Pernot, P.

2015-10-01

We performed High Performance Liquid Chromatography (HPLC) coupled to Orbitrap High Resolution Mass Spectrometry (OHR MS) analysis of Titan's tholins. This analysis allowed us to determine the exact composition and structure of some of the major components of tholins.

Validation of HPLC and UV spectrophotometric methods for the determination of meropenem in pharmaceutical dosage form.

PubMed

Mendez, Andreas S L; Steppe, Martin; Schapoval, Elfrides E S

2003-12-04

A high-performance liquid chromatographic method and a UV spectrophotometric method for the quantitative determination of meropenem, a highly active carbapenem antibiotic, in powder for injection were developed in present work. The parameters linearity, precision, accuracy, specificity, robustness, limit of detection and limit of quantitation were studied according to International Conference on Harmonization guidelines. Chromatography was carried out by reversed-phase technique on an RP-18 column with a mobile phase composed of 30 mM monobasic phosphate buffer and acetonitrile (90:10; v/v), adjusted to pH 3.0 with orthophosphoric acid. The UV spectrophotometric method was performed at 298 nm. The samples were prepared in water and the stability of meropenem in aqueous solution at 4 and 25 degrees C was studied. The results were satisfactory with good stability after 24 h at 4 degrees C. Statistical analysis by Student's t-test showed no significant difference between the results obtained by the two methods. The proposed methods are highly sensitive, precise and accurate and can be used for the reliable quantitation of meropenem in pharmaceutical dosage form.

Enantioselective determination of metconazole in multi matrices by high-performance liquid chromatography.

PubMed

He, Rujian; Fan, Jun; Tan, Qi; Lai, Yecai; Chen, Xiaodong; Wang, Tai; Jiang, Ying; Zhang, Yaomou; Zhang, Weiguang

2018-02-01

A reliable and effective HPLC analytical method has been developed to stereoselectively quantify metconazole in soil and flour matrices. Effects of polysaccharide chiral stationary phase, type and content of alcoholic modifier on separation of racemic metconazole have been discussed in detail. Resolution and quantitative determination of metconazole stereoisomers were performed by using an Enantiopak OD column, with the n-hexane-ethanol mixture (97:3, v/v) at the flow rate of 1.0mL/min. Then, extraction and cleanup procedures followed by the modified QuEChERS (quick, easy, cheap, effective, rugged and safe) method were used for metconazole racemate in soil and flour matrices. The residual analysis method was validated. Good linearity (R 2 ≥ 0.9997) and recoveries (94.98-104.89%, RSD ≤ 2.0%) for four metconazole stereoisomers were obtained. In brief, this proposed method showed good accuracy and precision, which might be applied in enantioselective determination, residual quantitative analysis, and degradation of metconazole in food and environmental matrices. Copyright © 2017 Elsevier B.V. All rights reserved.

Analysis of Flavone C-Glycosides in the Leaves of Clinacanthus nutans (Burm. f.) Lindau by HPTLC and HPLC-UV/DAD

PubMed Central

Chelyn, June Lee; Omar, Maizatul Hasyima; Mohd Yousof, Nor Syaidatul Akmal; Ranggasamy, Ramesh; Wasiman, Mohd Isa; Ismail, Zakiah

2014-01-01

Clinacanthus nutans (family Acanthaceae) has been used for the treatment of inflammation and herpes viral infection. Currently, there has not been any report on the qualitative and quantitative determination of the chemical markers in the leaves of C. nutans. The C-glycosidic flavones such as shaftoside, isoorientin, orientin, isovitexin, and vitexin have been found to be major flavonoids in the leaves of this plant. Therefore, we had developed a two-step method using thin-layer chromatography (TLC) and high pressure liquid chromatography (HPLC) for the rapid identification and quantification of the flavones C-glycosides in C. nutans leaves. The TLC separation of the chemical markers was achieved on silica gel 60 plate using ethyl acetate : formic acid : acetic acid : water (100 : 11 : 11 : 27 v/v/v/v) as the mobile phase. HPLC method was optimized and validated for the quantification of shaftoside, orientin, isovitexin, and vitexin and was shown to be linear in concentration range tested (0.4–200 μg/mL, r 2 ≥ 0.996), precise (RSD ≤ 4.54%), and accurate (95–105%). The concentration of shaftoside, orientin, vitexin, and isovitexin in C. nutans leave samples was 2.55–17.43, 0.00–0.86, 0.00–2.01, and 0.00–0.91 mmol/g, respectively. PMID:25405231

Determination of antioxidants by a novel on-line HPLC-cupric reducing antioxidant capacity (CUPRAC) assay with post-column detection.

PubMed

Celik, Saliha Esin; Ozyürek, Mustafa; Güçlü, Kubilay; Apak, Reşat

2010-07-26

A novel on-line HPLC-cupric reducing antioxidant capacity (CUPRAC) method was developed for the selective determination of polyphenols (flavonoids, simple phenolic and hydroxycinnamic acids) in complex plant matrices. The method combines chromatographic separation, constituent analysis, and post-column identification of antioxidants in plant extracts. The separation of polyphenols was performed on a C18 column using gradient elution with two different mobile phase solutions, i.e., MeOH and 0.2% o-phosphoric acid. The HPLC-separated antioxidant polyphenols in the extracts react with copper(II)-neocuproine (Cu(II)-Nc) reagent in a post-column reaction coil to form a derivative. The reagent is reduced by antioxidants to the copper(I)-neocuproine (Cu(I)-Nc) chelate having maximum absorption at 450 nm. The negative peaks of antioxidant constituents were monitored by measuring the increase in absorbance due to Cu(I)-Nc. The detection limits of polyphenols at 450 nm (in the range of 0.17-3.46 microM) after post-column derivatization were comparable to those at 280 nm UV detection without derivatization. The developed method was successfully applied to the identification of antioxidant compounds in crude extracts of Camellia sinensis, Origanum marjorana and Mentha. The method is rapid, inexpensive, versatile, non-laborious, uses stable reagents, and enables the on-line qualitative and quantitative estimation of antioxidant constituents of complex plant samples. Copyright 2010 Elsevier B.V. All rights reserved.

Optimization of sample preparation variables for wedelolactone from Eclipta alba using Box-Behnken experimental design followed by HPLC identification.

PubMed

Patil, A A; Sachin, B S; Shinde, D B; Wakte, P S

2013-07-01

Coumestan wedelolactone is an important phytocomponent from Eclipta alba (L.) Hassk. It possesses diverse pharmacological activities, which have prompted the development of various extraction techniques and strategies for its better utilization. The aim of the present study is to develop and optimize supercritical carbon dioxide assisted sample preparation and HPLC identification of wedelolactone from E. alba (L.) Hassk. The response surface methodology was employed to study the optimization of sample preparation using supercritical carbon dioxide for wedelolactone from E. alba (L.) Hassk. The optimized sample preparation involves the investigation of quantitative effects of sample preparation parameters viz. operating pressure, temperature, modifier concentration and time on yield of wedelolactone using Box-Behnken design. The wedelolactone content was determined using validated HPLC methodology. The experimental data were fitted to second-order polynomial equation using multiple regression analysis and analyzed using the appropriate statistical method. By solving the regression equation and analyzing 3D plots, the optimum extraction conditions were found to be: extraction pressure, 25 MPa; temperature, 56 °C; modifier concentration, 9.44% and extraction time, 60 min. Optimum extraction conditions demonstrated wedelolactone yield of 15.37 ± 0.63 mg/100 g E. alba (L.) Hassk, which was in good agreement with the predicted values. Temperature and modifier concentration showed significant effect on the wedelolactone yield. The supercritical carbon dioxide extraction showed higher selectivity than the conventional Soxhlet assisted extraction method. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Simple Detection Methods for Antinutritive Factor β-ODAP Present in Lathyrus sativus L. by High Pressure Liquid Chromatography and Thin Layer Chromatography.

PubMed

Ghosh, Bidisha; Mitra, Joy; Chakraborty, Saikat; Bhattacharyya, Jagannath; Chakraborty, Anirban; Sen, Soumitra Kumar; Neerathilingam, Muniasamy

2015-01-01

Lathyrus sativus L. (Grass pea) is the source for cheap and nutritious food choice in drought and famine susceptible zones in greater part of North India and Africa. The non-protein amino acid β-N-oxalyl-L-α,β-diaminopropionic acid (β-ODAP) has been known for decades for its potent neurotoxic effect, causing irreversible neurodegenerative disease "neurolathyrism", present in both seed and leaf of Lathyrus sativus L. and other species in varying proportions. It is crucial to establish a rapid as well as reliable detection methodology for β-ODAP content in various Lathyrus plants. Currently available HPLC based methods involve multi-step derivatization of the sample. To overcome this, we have developed β-ODAP analysis method by HPLC without any prior derivatization. This method is statistically significant in the range of 2 to 100μg/ml and exhibited linear response with r2 > 0.99. Limit of detection and quantitation of the later method was determined to be 5.56 μg/ml and 16.86 μg/ml, respectively. In addition to this, a TLC based method has also been developed. The limit of detection of β-ODAP is 0.6μg and for its substrate, L-1,2-diaminopropionic acid is 5μg. Both HPLC and TLC methods were validated by conducting in-vitro bioconversion test to detect the presence of biocatalyst in plant extract. This method is economical, rapid and simple.

Chromatographic determination of itopride hydrochloride in the presence of its degradation products.

PubMed

Kaul, Neeraj; Agrawal, Himani; Maske, Pravin; Rao, Janhavi Ramchandra; Mahadik, Kakasaheb Ramoo; Kadam, Shivajirao S

2005-08-01

Two sensitive and reproducible methods are described for the quantitative determination of itopride hydrochloride (IH) in the presence of its degradation products. The first method is based on HPLC separation on a reversed phase Kromasil column [C18 (5-microm, 25 cm x 4.6 mm, ID)] at ambient temperature using a mobile phase consisting of methanol and water (70:30, v/v) adjusted to pH 4.0 with orthophosphoric acid with UV detection at 258 nm. The flow rate was 1.0 mL per min with an average operating pressure of 180 kg/cm2. The second method is based on HPTLC separation on silica gel 60 F254 using toluene:methanol:chloroform:10% ammonia (5.0:3.0:6.0:0.1, v/v/v/v) as mobile phase at 270 nm. The analysis of variance (ANOVA) and Student's t-test were applied to correlate the results of IH determination in dosage form by means of HPLC and HPTLC methods. The drug was subjected to acid and alkali hydrolysis, oxidation, dry heat, wet heat treatment, UV, and photodegradation. The proposed HPLC method was utilized to investigate the kinetics of the acidic, alkaline, and oxidative degradation processes at different temperatures and the apparent pseudo-first-order rate constant, half-life, and activation energy were calculated. In addition the pH-rate profile of degradation of IH in constant ionic strength buffer solutions in the pH range 2-11 was studied.

Quantitative analysis of active compounds in pharmaceutical preparations by use of attenuated total-reflection Fourier transform mid-infrared spectrophotometry and the internal standard method.

PubMed

Sastre Toraño, J; van Hattum, S H

2001-10-01

A new method is presented for the quantitative analysis of compounds in pharmaceutical preparations Fourier transform (FT) mid-infrared (MIR) spectroscopy with an attenuated total reflection (ATR) module. Reduction of the quantity of overlapping absorption bands, by interaction of the compound of interest with an appropriate solvent, and the employment of an internal standard (IS), makes MIR suitable for quantitative analysis. Vigabatrin, as active compound in vigabatrin 100-mg capsules, was used as a model compound for the development of the method. Vigabatrin was extracted from the capsule content with water after addition of a sodium thiosulfate IS solution. The extract was concentrated by volume reduction and applied to the FTMIR-ATR module. Concentrations of unknown samples were calculated from the ratio of the vigabatrin band area (1321-1610 cm(-1)) and the IS band area (883-1215 cm(-1)) using a calibration standard. The ratio of the area of the vigabatrin peak to that of the IS was linear with the concentration in the range of interest (90-110 mg, in twofold; n=2). The accuracy of the method in this range was 99.7-100.5% (n=5) with a variability of 0.4-1.3% (n=5). The comparison of the presented method with an HPLC assay showed similar results; the analysis of five vigabatrin 100-mg capsules resulted in a mean concentration of 102 mg with a variation of 2% with both methods.

High performance liquid chromatography time of flight electrospray ionization mass spectrometry for quantification of sesquiterpenes in Chrysanthemi indici Flos active extract

PubMed Central

Fu, Ling; Wang, Pan; Sun, Yiqun; Wang, Yangyang; Zhao, Jing; Ye, Yuting; Zhang, Yanbin; Bi, Yuefeng

2015-01-01

Background: Chrysanthemi indici Flos, a traditional herbal medicine is used to clearing heat–toxicity, removing the liver fire, and improving eyesight. In our preliminary work, an active extract of CTC in C. An indici Flos with anti-hepatitis B virus and liver protective activity was found by HepG2.2.1.5 test and experiment of protein synthesis in mice's injured liver. In this work, we aimed to study the active faction CTC further by qualitative and quantitative analysis method. Materials and Methods: High performance liquid chromatography time of flight electrospray ionization mass spectrometry (HPLC TOF ESI-MS) analysis method of the CTC was established. Cumambrin A and angeloylcumambrin B in CTC were analyzed by high performance liquid chromatography-ultraviolet-evaporative light scattering detector (HPLC-UV-ELSD) analysis methods. A binary gradient elution program was conducted for chromatographic separation with acetonitrile (A) and ultrapure water (B) as follows: 0–10 min, 42–46% A; 10–20 min, 46–55% A; 20–25 min, 55–60% A; and 25–35 min, 60–75% A. The column temperature and UV wavelength were set at 30°C and 205 nm. Result: Ten constituents including (3R, 5R, 6S, 7S, 10R)-7-(2-hydroxy-2-propyl)-10-methyl-4-methyleneperhy, dronaphthal-ene-3, 5, 6-triol acetone solvate; (+)-edusmance-4, (14)-ene-11, 13-diol; linarin; luteolin; apigenin; tricin; 5, 3’,4’- trimethyl-6,7-dimethoxy flavones; cumambrin A; acacetin; and angeloylcumambrin B in CTC were identified by HPLC TOF ESI-MS. The contents of sesquiterpenes in CTC were decreased by storing years. Conclusions: The results showed that both UV and ELSD methods were feasible, accurate, and the determination results were in good consistency. The contents of two sesquiterpenes decreased with storing years. Two sesquiterpenes could be used as quality control for C. indici flos CTC. PMID:26600718

Analysis of Levodopa Content in Commercial Mucuna pruriens Products Using High-Performance Liquid Chromatography with Fluorescence Detection.

PubMed

Soumyanath, Amala; Denne, Tanya; Hiller, Amie; Ramachandran, Shaila; Shinto, Lynne

2018-02-01

Mucuna pruriens (MP) seeds contain levodopa (up to 2% by weight) and have been used in traditional Indian medicine to treat an illness named "Kampavata," now understood to be Parkinson's disease (PD). Studies have shown MP to be beneficial, and even superior, to levodopa alone in treating PD symptoms. Commercial products containing MP are readily available from online and retail sources to patients and physicians. Products often contain extracts of MP seeds, with significantly higher levodopa content than the seeds. However, MP products have limited regulatory controls with respect to quality and content of active ingredient. The aim of this study was to apply a quantitative method to determine levodopa content in readily available MP products that might be used by patients or in research studies. Levodopa present in six commercial MP products was quantified by solvent extraction followed by reversed-phase high-performance liquid chromatography (HPLC) coupled to fluorescence detection (FD). Certificates of analysis (COA) were obtained, from manufacturers of MP products, to assess the existence and implementation of specifications for levodopa content. HPLC-FD analysis revealed that the levodopa content of the six commercial MP products varied from 6% to 141% of individual label claims. No product contained levodopa within normal pharmacopeial limits of 90%-110% label claim. The maximum daily dose of levodopa delivered by the products varied from 14.4 to 720 mg/day. COAs were inconsistent in specifications for and verification of levodopa content. The commercial products tested varied widely in levodopa content, sometimes deviating widely from the label claim. These deficiencies could impact efficacy and safety of MP products used by PD patients and compromise the results of scientific studies on MP products. The HPLC-FD method described in this study could be utilized by both manufacturers and scientific researchers to verify levodopa content of MP products.

A validated bioanalytical HPLC method for pharmacokinetic evaluation of 2-deoxyglucose in human plasma

PubMed Central

Gounder, Murugesan K.; Lin, Hongxia; Stein, Mark; Goodin, Susan; Bertino, Joseph R.; Kong, Ah-Ng Tony; DiPaola, Robert S.

2015-01-01

2-deoxyglucose (2-DG), an analog of glucose, is widely used to interfere with the glycolysis in tumor cells and studied as a therapeutic approach in clinical trials. To evaluate the pharmacokinetics of 2-DG, we describe the development and validation of a sensitive HPLC fluorescent method for the quantitation of 2-DG in plasma. Plasma samples were deproteinized with methanol and the supernatant was dried at 45°C. The residues were dissolved in methanolic sodium acetate/boric acid solution. 2-DG and other monosaccharides were derivatized to 2-aminobenzoic acid derivatives in a single step in the presence of sodium cyanoborohydride at 80°C for 45min. The analytes were separated on a YMC ODS C18 reversed-phase column using gradient elution. The excitation and emission wavelengths were set at 360 and 425nm. The 2-DG calibration curves were linear over the range of 0.63 to 300μg/mL with the limit of detection of 0.5μg/mL. The assay provided satisfactory intra-day and inter-day precision with RSD less than 9.8% and the accuracy ranged from 86.8% to 110.0%. The HPLC method is reproducible and suitable for the quantitation of 2-DG in plasma. The method was successfully applied to characterize the pharmacokinetics profile of 2-DG in patients with advanced solid tumors. PMID:21932382

Nontargeted quantitation of lipid classes using hydrophilic interaction liquid chromatography-electrospray ionization mass spectrometry with single internal standard and response factor approach.

PubMed

Cífková, Eva; Holčapek, Michal; Lísa, Miroslav; Ovčačíková, Magdaléna; Lyčka, Antonín; Lynen, Frédéric; Sandra, Pat

2012-11-20

The identification and quantitation of a wide range of lipids in complex biological samples is an essential requirement for the lipidomic studies. High-performance liquid chromatography-mass spectrometry (HPLC/MS) has the highest potential to obtain detailed information on the whole lipidome, but the reliable quantitation of multiple lipid classes is still a challenging task. In this work, we describe a new method for the nontargeted quantitation of polar lipid classes separated by hydrophilic interaction liquid chromatography (HILIC) followed by positive-ion electrospray ionization mass spectrometry (ESI-MS) using a single internal lipid standard to which all class specific response factors (RFs) are related to. The developed method enables the nontargeted quantitation of lipid classes and molecules inside these classes in contrast to the conventional targeted quantitation, which is based on predefined selected reaction monitoring (SRM) transitions for selected lipids only. In the nontargeted quantitation method described here, concentrations of lipid classes are obtained by the peak integration in HILIC chromatograms multiplied by their RFs related to the single internal standard (i.e., sphingosyl PE, d17:1/12:0) used as common reference for all polar lipid classes. The accuracy, reproducibility and robustness of the method have been checked by various means: (1) the comparison with conventional lipidomic quantitation using SRM scans on a triple quadrupole (QqQ) mass analyzer, (2) (31)P nuclear magnetic resonance (NMR) quantitation of the total lipid extract, (3) method robustness test using subsequent measurements by three different persons, (4) method transfer to different HPLC/MS systems using different chromatographic conditions, and (5) comparison with previously published results for identical samples, especially human reference plasma from the National Institute of Standards and Technology (NIST human plasma). Results on human plasma, egg yolk and porcine liver extracts are presented and discussed.

Interface for liquid chromatograph-mass spectrometer

DOEpatents

Andresen, B.D.; Fought, E.R.

1989-09-19

A moving belt interface is described for real-time, high-performance liquid chromatograph (HPLC)/mass spectrometer (MS) analysis which strips away the HPLC solvent as it emerges from the end of the HPLC column and leaves a residue suitable for mass-spectral analysis. The interface includes a portable, stand-alone apparatus having a plural stage vacuum station, a continuous ribbon or belt, a drive train magnetically coupled to an external drive motor, a calibrated HPLC delivery system, a heated probe tip and means located adjacent the probe tip for direct ionization of the residue on the belt. The interface is also capable of being readily adapted to fit any mass spectrometer. 8 figs.

Interface for liquid chromatograph-mass spectrometer

DOEpatents

Andresen, Brian D.; Fought, Eric R.

1989-01-01

A moving belt interface for real-time, high-performance liquid chromatograph (HPLC)/mass spectrometer (MS) analysis which strips away the HPLC solvent as it emerges from the end of the HPLC column and leaves a residue suitable for mass-spectral analysis. The interface includes a portable, stand-alone apparatus having a plural stage vacuum station, a continuous ribbon or belt, a drive train magnetically coupled to an external drive motor, a calibrated HPLC delivery system, a heated probe tip and means located adjacent the probe tip for direct ionization of the residue on the belt. The interface is also capable of being readily adapted to fit any mass spectrometer.

Recent Advances in Analytical Pyrolysis to Investigate Organic Materials in Heritage Science.

PubMed

Degano, Ilaria; Modugno, Francesca; Bonaduce, Ilaria; Ribechini, Erika; Colombini, Maria Perla

2018-06-18

The molecular characterization of organic materials in samples from artworks and historical objects traditionally entailed qualitative and quantitative analyses by HPLC and GC. Today innovative approaches based on analytical pyrolysis enable samples to be analysed without any chemical pre-treatment. Pyrolysis, which is often considered as a screening technique, shows previously unexplored potential thanks to recent instrumental developments. Organic materials that are macromolecular in nature, or undergo polymerization upon curing and ageing can now be better investigated. Most constituents of paint layers and archaeological organic substances contain major insoluble and chemically non-hydrolysable fractions that are inaccessible to GC or HPLC. To date, molecular scientific investigations of the organic constituents of artworks and historical objects have mostly focused on the minor constituents of the sample. This review presents recent advances in the qualitative and semi-quantitative analyses of organic materials in heritage objects based on analytical pyrolysis coupled with mass spectrometry. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effect of Agave americana and Agave salmiana Ripeness on Saponin Content from Aguamiel (Agave Sap).

PubMed

Leal-Díaz, Ana María; Santos-Zea, Liliana; Martínez-Escobedo, Hilda Cecilia; Guajardo-Flores, Daniel; Gutiérrez-Uribe, Janet Alejandra; Serna-Saldivar, Sergio Othón

2015-04-22

Steroidal saponins have shown beneficial health effects. Agave spp. leaves and rhizomes are sources of these compounds, but their presence has not been reported in the aguamiel. Aguamiel is the sweet edible sap from mature agave, and its quality is influenced by the plant ripening stage. The purpose of this research was to identify and quantitate saponins in aguamiel from Agave americana and Agave salmiana at two ripening stages. Saponins and sapogenins were identified with HPLC/ESI-MS/TOF and quantitated with HPLC/ELSD. Results proved the presence of saponins derived from kammogenin, manogenin, gentrogenin, and hecogenin. The saponin content in aguamiel from immature A. salmiana was 2-fold higher (478.3 protodioscin equivalents (PE) μg/g aguamiel (DM)) compared with A. americana (179.0 PE μg/g aguamiel (DM)). In both species, saponin content decreased when plants reached sexual maturity. This should be considered before evaluating the effects of Agave spp. as a source of bioactive saponins.

Development and validation of a high performance liquid chromatographic method for simultaneous determination of vitamins A and D3 in fluid milk products.

PubMed

Chen, Yang; Reddy, Ravinder M; Li, Wenjing; Yettlla, Ramesh R; Lopez, Salvador; Woodman, Michael

2015-01-01

An HPLC method for simultaneous determination of vitamins A and D3 in fluid milk was developed and validated. Saponification and extraction conditions were studied for optimum recovery and simplicity. An RP HPLC system equipped with a C18 column and diode array detector was used for quantitation. The method was subjected to a single-laboratory validation using skim, 2% fat, and whole milk samples at concentrations of 50, 100, and 200% of the recommended fortification levels for vitamins A and D3 for Grade "A" fluid milk. The method quantitation limits for vitamins A and D3 were 0.0072 and 0.0026 μg/mL, respectively. Average recoveries between 94 and 110% and SD values ranging from 2.7 to 6.9% were obtained for both vitamins A and D3. The accuracy of the method was evaluated using a National Institute of Standards and Technology standard reference material (1849a) and proficiency test samples.

Analytical Method Development and Validation for the Simultaneous Estimation of Abacavir and Lamivudine by Reversed-phase High-performance Liquid Chromatography in Bulk and Tablet Dosage Forms.

PubMed

Raees Ahmad, Sufiyan Ahmad; Patil, Lalit; Mohammed Usman, Mohammed Rageeb; Imran, Mohammad; Akhtar, Rashid

2018-01-01

A simple rapid, accurate, precise, and reproducible validated reverse phase high performance liquid chromatography (HPLC) method was developed for the determination of Abacavir (ABAC) and Lamivudine (LAMI) in bulk and tablet dosage forms. The quantification was carried out using Symmetry Premsil C18 (250 mm × 4.6 mm, 5 μm) column run in isocratic way using mobile phase comprising methanol: water (0.05% orthophosphoric acid with pH 3) 83:17 v/v and a detection wavelength of 245 nm and injection volume of 20 μl, with a flow rate of 1 ml/min. In the developed method, the retention times of ABAC and LAMI were found to be 3.5 min and 7.4 min, respectively. The method was validated in terms of linearity, precision, accuracy, limits of detection, limits of quantitation, and robustness in accordance with the International Conference on Harmonization guidelines. The assay of the proposed method was found to be 99% - 101%. The recovery studies were also carried out and mean % recovery was found to be 99% - 101%. The % relative standard deviation from reproducibility was found to be <2%. The proposed method was statistically evaluated and can be applied for routine quality control analysis of ABAC and LAMI in bulk and in tablet dosage form. Attempts were made to develop RP-HPLC method for simultaneous estimation of Abacavir and Lamivudine for the RP-HPLC method. The developed method was validated according to the ICH guidelines. The linearity, precision, range, robustness were within the limits as specified by the ICH guidelines. Hence the method was found to be simple, accurate, precise, economic and reproducible. So the proposed methods can be used for the routine quality control analysis of Abacavir and Lamivudine in bulk drug as well as in formulations. Abbreviations Used: HPLC: High-performance liquid chromatography, UV: Ultraviolet, ICH: International Conference on Harmonization, ABAC: Abacavir, LAMI: Lamivudine, HIV: Human immunodeficiency virus, AIDS: Acquired immunodeficiency syndrome, NRTI: Nucleoside reverse transcriptase inhibitors, ARV: Antiretroviral, RSD: Relative standard deviation, RT: Retention time, SD: Standard deviation.

Preparation of clenbuterol imprinted monolithic polymer with hydrophilic outer layers by reversible addition-fragmentation chain transfer radical polymerization and its application in the clenbuterol determination from human serum by on-line solid-phase extraction/HPLC analysis.

PubMed

Li, Xiaobing; Zhou, Man; Turson, Mamat; Lin, Shen; Jiang, Ping; Dong, Xiangchao

2013-05-21

A novel imprinted monolithic material with the ability of protein exclusion was developed for the selective extraction of clenbuterol (CLE) from biological samples by direct injection in the HPLC analysis. The material has an imprinted inner structure and hydrophilic outer layer. The reversible addition-fragmentation chain transfer (RAFT) polymerization was employed in the material preparation by a two-step procedure. In the first step, clenbuterol imprinted monolithic polymer was synthesized by combining the molecular imprinting and the RAFT polymerization techniques. The resulting monolithic polymer has a RAFT chain transfer agent (trithioester groups) in its structure, which was used to graft poly(glycerol mono-methacrylate) [pGMMA] in the second step by post-RAFT polymerization. The hydrophilic pGMMA layers grafted on the surface of the imprinted monolith created barriers for protein diffusion. More than 90% of bovine serum albumin can be excluded from the pGMMA coated monolithic column. Meanwhile the clenbuterol was retained selectively with a large retention factor. The result indicated that the column, denoted as RA-MIM, has both the merits of a molecularly imprinted polymer and restricted access material. By using RA-MIM as the solid-phase extraction pre-column, an on-line column-switching HPLC method for the determination of clenbuterol in human serum has been established and validated. The recoveries of clenbuterol from the serum were 87.3-96.9% in the spiked level 2-1000 ng mL(-1). Both good linearity (R = 0.999) and acceptable reproducibility (RSD < 7.0%) were obtained. The limit of detection and the limit of quantitation were 0.7 ng mL(-1) and 2.0 ng mL(-1) respectively, which is sensitive in terms of UV detection. The results have demonstrated that the RAFT polymerization can be used to synthesize bi-functional monolithic columns by using its living reaction property. The resulting RA-MIM in this research can be used for efficient clenbuterol determination by HPLC from biological samples.

Sensitive and selective determination of methylenedioxylated amphetamines by high-performance liquid chromatography with fluorimetric detection.

PubMed

Sadeghipour, F; Veuthey, J L

1997-11-07

A rapid, sensitive and selective liquid chromatographic method with fluorimetric detection was developed for the separation and quantification of four methylenedioxylated amphetamines without interference of other drugs of abuse and common substances found in illicit tablets. The method was validated by examining linearity, precision and accuracy as well as detection and quantification limits. Methylenedioxylated amphetamines were quantified in eight tablets from illicit drug seizures and results were quantitatively compared to HPLC-UV analyses. To demonstrate the better sensitivity of the fluorimetric detection, methylenedioxylated amphetamines were analyzed in serum after a liquid-liquid extraction procedure and results were also compared to HPLC-UV analyses.

Quantitative analysis of indigo and indigo precursors in leaves of Isatis spp. and Polygonum tinctorium.

PubMed

Gilbert, Kerry G; Maule, Hamish G; Rudolph, Bernd; Lewis, Mervyn; Vandenburg, Harold; Sales, Ester; Tozzi, Sabrina; Cooke, David T

2004-01-01

Analysis of extracts from two woad species (Isatis tinctoria and Isatis indigotica) and Polygonum tinctorium revealed that only one indigo precursor (indican) was present in Polygonum, but two precursors were found in Isatis spp. This was done using high performance liquid chromatography (HPLC), coupled to an evaporative light scattering detector (ELSD). In Isatis spp., the indigo precursors indican and a fraction representing isatan B were identified. The proportion of indican and isatan B was different between the two Isatis spp. tested. For the first time, it was possible to quantify the precursors in woad plant species, and the results were found to be in good agreement with those made from total indigo quantification using two different spectrophotometric methods or a derivatization technique.

Comparison of HPLC and CE for the analysis of dichlorprop in a case of intoxication.

PubMed

West, A; Frost, M; Köhler, H

1997-01-01

A 49-year-old white male was found lying unconscious at home. He had vomited, his mouth was filled with a white foam and a pungent odour filled the room. After emergency treatment blood, urine and stomach contents were screened for drugs after acid and alkaline extraction with subsequent derivatisation and GC-MS analysis. Large quantites of 2,4-dichlorophenoxypropionic acid (dichlorprop, 2,4-DP) were found in all acid extracts. The man died 3 h later in hospital. Body fluids and tissues obtained at autopsy were analysed for 2,4-DP by high-performance liquid chromatography and capillary electrophoresis. The concentrations of 2,4-DP in cardiac blood, stomach contents, bile, liver, spleen, kidney and brain found by both methods were very similar.

Adulteration and cultivation region identification of American ginseng using HPLC coupled with multivariate analysis

PubMed Central

Yu, Chunhao; Wang, Chong-Zhi; Zhou, Chun-Jie; Wang, Bin; Han, Lide; Zhang, Chun-Feng; Wu, Xiao-Hui; Yuan, Chun-Su

2014-01-01

American ginseng (Panax quinquefolius) is originally grown in North America. Due to price difference and supply shortage, American ginseng recently has been cultivated in northern China. Further, in the market, some Asian ginsengs are labeled as American ginseng. In this study, forty-three American ginseng samples cultivated in the USA, Canada or China were collected and 14 ginseng saponins were determined using HPLC. HPLC coupled with hierarchical cluster analysis and principal component analysis was developed to identify the species. Subsequently, an HPLC-linear discriminant analysis was established to discriminate cultivation regions of American ginseng. This method was successfully applied to identify the sources of 6 commercial American ginseng samples. Two of them were identified as Asian ginseng, while 4 others were identified as American ginseng, which were cultivated in the USA (3) and China (1). Our newly developed method can be used to identify American ginseng with different cultivation regions. PMID:25044150

Rapid Quantitative Analysis of Naringenin in the Fruit Bodies of Inonotus vaninii by Two-phase Acid Hydrolysis Followed by Reversed Phase-high Performance Liquid Chromatography-ultra Violet.

PubMed

Guohua, Xia; Pan, Ruirong; Bao, Rui; Ge, Yanru; Zhou, Cunshan; Shen, Yuping

2017-01-01

Sanghuang is one of mystical traditional Chinese medicines recorded earliest 2000 years ago, that included various fungi of Inonotus genus and was well-known for antitumor effect in modern medicine. Inonotus vaninii is grown in natural forest of Northeastern China merely and used as Sanghuang commercially, but it has no quality control specification until now. This study was to establish a rapid method of two-phase acid hydrolysis followed by reversed phase-high performance liquid chromatography-ultra violet (RP-HPLC-UV) to quantify naringenin in the fruit body of I. vaninii . Sample solution was prepared by pretreatment of raw material in two-phase acid hydrolysis and the hydrolysis technology was optimized. After reconstitution, analysis was performed using RP-HPLC-UV. The method validation was investigated and the naringenin content of sample and comparison were determined. The naringenin was obtained by two-phase acid hydrolysis method, namely, 10.0 g of raw material was hydrolyzed in 200 mL of 1% sulfuric acid aqueous solution (v/v) and 400 mL of chloroform in oil bath at 110°C for 2 h. Good linearity ( r = 0.9992) was achieved between concentration of analyte and peak area. The relative standard deviation (RSD) of precision was 2.47% and the RSD of naringenin contents for repeatability was 3.13%. The accuracy was supported with recoveries at 96.37%, 97.30%, and 99.31%. The sample solution prepared using the proposed method contained higher content of naringenin than conventional method and was stable for 8 h. Due to the high efficiency of sample preparation and high reliability of the HPLC method, it is feasible to use this method for routine analysis of naringenin in the fungus. A convenient two-phase acid hydrolysis was employed to produce naringenin from raw material, and then an efficient and reliable reversed phase-high performance liquid chromatography-ultra violet method was established to monitor naringenin in the fruit bodies of Inonotus vaninii . The newly established method could be used to control the quality of the herb. Abbreviations used: RP-HPLC-UV: Reversed Phase-High Performance Liquid Chromatography-Ultra Violet, RSD: Relative Standard Deviation, EtOAc: Ethyl acetate, ACN: Acetonitrile, MeOH: Methanol, RH: Relative Humility.

Analysis of black carbon molecular markers by two chromatographic methods (GC-FID and HPLC-DAD)

NASA Astrophysics Data System (ADS)

Schneider, Maximilian P. W.; Smittenberg, Rienk H.; Dittmar, Thorsten; Schmidt, Michael W. I.

2010-05-01

The analysis of benzenepolycarboxylic acids (BPCA) as a quantitative measure for black carbon (BC) in soil and sediment samples is a well-established method [1, 2]. Briefly, the oxidation of polycondensated BC molecules forms seven molecular markers, which can be assigned to BC, and which subsequently can be quantified by GC-FID (gas chromatography with flame ionization detector). Recently this method has been refined for BC quantification in seawater samples measuring BPCA on HPLC-DAD (High performance liquid chromatography with diode array detector) [3]. However, a systematic comparison of BC as determined by both analytical techniques would be essential to the calculation of global BC budgets, but is lacking. Here we present data for the systematic comparison of the two BPCA methods, both for quantity and quality. We prepared chars under well-defined laboratory conditions. Chestnut hardwood chips and rice straw were pyrolysed at temperatures between 200 and 1000°C under constant N2 stream. The BC contents of the chars have been analysed using the BPCA extraction method followed by either GC-FID or HPLC-DAD quantification [4]. It appears that the GC-FID method yields systematically lower concentrations of BPCA in the chars compared to the HPLC-DAD method. Possible reasons for the observed difference are i) higher losses of sample material during preparation for GC-FID; ii) different quality of the linear regression used for quantification; iii) incomplete derivatisation of B5CA and B6CA, which is needed for GC-FID analysis. In a next step, we will test different derivatisation procedures (methylation with dimethyl sulfate or diazomethane, and silylation) for their influence on the GC-FID results. The aim of this study is to test if black carbon can be quantified in soil, sediment and water samples using one single method - a crucial step when attempting a global BC budget. References: [1] Brodowski, S., Rodionov, A., Haumeier L., Glaser, B., Amelung, W. (2005) Org. Geochem. 36, 1299-1310. [2] Glaser, B., Haumeier, L., Guggenberger, G., Zech, W. (1998) Org. Geochem. 29, 811-819. [3] Dittmar, T. (2008) Org. Geochem. 39. 396-407. [4] Schneider, M.P.W., Hilf, M., Vogt, U.F., Schmidt, M.W.I., Org. Geochem. (submitted)

Chemically bonded stationary phases that use synthetic hosts containing aromatic binding clefts: HPLC analysis of nitro-substituted polycyclic aromatic hydrocarbons.

PubMed Central

Zimmerman, S C; Saionz, K W; Zeng, Z

1993-01-01

The synthesis of hosts with improved binding affinities for nitroaromatic guests is described. Association constants for several host-guest complexes were measured in chloroform solution and ranged over three orders of magnitude. Two hosts were covalently linked to silica gel to produce chemically bonded stationary phases for HPLC. The use of these phases for HPLC analysis of nitro-substituted polycyclic aromatic hydrocarbons is discussed. PMID:8433981

Quantitative Determination of Corrosion Inhibitor Levels in Jet Fuels by HPLC.

DTIC Science & Technology

1986-01-06

CLASSIFICATION lb RESTRICTIVE MARKINGS Unclassified None - SECURITY CLASSIFICATION AUTHORITY 3 DISTRIBJTION/AVAILABILITY OF REPORT DECLASSIFICATION/DOWNGRADING...Inst. Pet., 51, 502 pp. 348 - 353 (October 1965). 3. Hillman, D.E., Paul, J.I. and Cobbold , D.G., "Determination of ripeline Corrosion Inhibitor (Hitec E

Mallow carotenoids determined by high-performance liquid chromatography

USDA-ARS?s Scientific Manuscript database

Mallow (corchorus olitorius) is a green vegetable, which is widely consumed either fresh or dry by Middle East population. This study was carried out to determine the contents of major carotenoids quantitatively in mallow, by using a High Performance Liquid Chromatography (HPLC) equipped with a Bis...

Quality control and identification of steroid saponins in crude extracts from Dioscorea zingiberensis C. H. Wright by fingerprint with HPLC-ELSD and HPLC-ESI-Quadrupole/Time-of-fight tandem mass spectrometry

PubMed Central

Zhang, Xinxin; Liang, Jinru; Liu, Jianli; Zhao, Ye; Gao, Juan; Sun, Wenji; Ito, Yoichiro

2014-01-01

In this study, a fingerprint of steroid saponins, the major bioactive constituents in the crude extracts from Dioscorea zingiberensis C. H. Wright (DZW), has been established for the first time by high-performance liquid chromatography coupled with evaporative light scattering detector (HPLC-ELSD) and the simultaneous characterization of the steroid saponins by high-performance liquid chromatography coupled with electrospray ionization-mass spectrometry and quadrupole tandem time-of-fight mass analyzers detection (HPLC-ESI-Q/TOF). These HPLC analyses were both carried out on a Welchrom C18 column (250 mm × 4.6 mm I.D., 5 μm) with a mobile phase composed of water and acetonitrile under gradient elution. There were 68 common characteristic peaks in the fingerprints, in which 12 of them were confirmed by comparing their mass spectra and retention times with those of the reference compounds. In order to identify the other unknown peaks, their fragmentation behaviors characteristic for the major groups of steroid saponins from DZW with six types of aglycone skeletons were discussed in detail, and possible MS/MS fragmentation pathways were proposed for aiding the structural identification of these components. According to the summarized fragmentation patterns, these peaks were tentatively assigned by matching their empirical molecular formula with those of the published compounds, or by elucidating their quasi-molecular ions and fragment ions referring to available literature information when the reference standards were unavailable. As a result, 22 steroid saponins were found in DZW for the first time. In addition, the quantitative analysis of the 12 known peaks was accomplished at the same time which indicated that there was a great variability in the amount of these active compounds in different batches in the crude extracts. This approach could demonstrate that the fingerprint could be considered to be a suitable tool to comprehensively improve the quality control of DZW, and the identification and structural elucidation of the peaks in the fingerprint may provide important experimental data for further pharmacological and clinical researches. PMID:24418811

Development and Validation of a Simultaneous RP-HPLCUV/DAD Method for Determination of Polyphenols in Gels Containing S. terebinthifolius Raddi (Anacardiaceae)

PubMed Central

Carvalho, Melina G.; Aragão, Cícero F. S; Raffin, Fernanda N.; de L. Moura, Túlio F. A.

2017-01-01

Topical gels containing extracts of Schinus terebinthifolius have been used to treat bacterial vaginosis. It has been reported that this species has antimicrobial, anti-inflammatory and anti-ulcerogenic properties, which can be attributed to the presence of phenolic compounds. In this work, a sensitive and selective reversed-phase HPLC-UV/DAD method for the simultaneous assay of six polyphenols that could be present in S. terebinthifolius was developed. The method was shown to be accurate and precise. Peak purity and similarity index both exceeded 0.99. Calibration curves were linear over the concentration range studied, with correlation coefficients between 0.9931 and 0.9974. This method was used to determine the polyphenol content of a hydroalcoholic extract and pharmacy-compounded vaginal gel. Although the method is useful to assess the 6 phenolic compounds, some compounds could not be detected in the products. SUMMARY A sensitive, selective, accurate and precise reversed-phase HPLC-UV/DAD method for the simultaneous assay of six polyphenols in S. terebinthifolius Raddi Abbreviations used: RP-HPLC-UV/DAD: Reverse Phase High Performance Liquid Chromatograph with Ultraviolet and Diode Array Detector, HPLC: High Performance Liquid Chromatograph, HPLC-UV: High Performance Liquid Chromatograph with Ultraviolet Detector, ANVISA: Brazilian National Health Surveillance Agency, LOD: Limit of detection, LOQ: Limit of quantitation PMID:28539726

[Analysis of different forms Linderae Radix based on HPLC and NIRS fingerprints].

PubMed

Du, Wei-Feng; Yue, Xian-Ke; Wu, Yao; Ge, Wei-Hong; Lu, Tu-Lin; Wang, Zhi-Min

2016-10-01

Three different forms of Linderae Radix were evaluated by HPLC combined with NIRS fingerprint. The Linderae Radix was divided into three forms, including spindle root, straight root and old root. The HPLC fingerprints were developed, and then cluster analysis was performed using the SPSS software. The near-infrared spectra of Linderae Radix was collected, and then established the discriminant analysis model. The similarity values of the spindle root and straight root all were above 0.990, while the similarity value of the old root was less than 0.850. Two forms of Linderae Radix were obviously divided into three parts by the NIRS model and Cluster analysis. The results of HPLC and FT-NIR analysis showed the quality of Linderae Radix old root was different from the spindle root and straight root. The combined use of the two methods could identify different forms of Linderae Radix quickly and accurately. Copyright© by the Chinese Pharmaceutical Association.

Selenium speciation analysis of Misgurnus anguillicaudatus selenoprotein by HPLC-ICP-MS and HPLC-ESI-MS/MS

USDA-ARS?s Scientific Manuscript database

Analytical methods for selenium (Se) speciation were developed using high performance liquid chromatography (HPLC) coupled to either inductively coupled plasma mass spectrometry (ICP-MS) or electrospray ionization tandem mass spectrometry (ESI-MS/MS). Separations of selenomethionine (Se-Met) and sel...

Variability of sesquiterpene lactones in Neurolaena lobata of different origin.

PubMed

Passreiter, C M; Aldana, B E

1998-06-01

Leaves of Neurolaena lobata (L.) R. Br. originating from Guatemala, were analyzed using HPLC for their qualitative and quantitative sesquiterpene lactone contents. Significant differences in the individual amounts of neurolenins and furanoheliangolides were found between four natural populations. When plants were cultivated on proving fields at two different localities in Guatemala, their sesquiterpene lactone patterns matched the natural population, but differed quantitatively. The meaning of these differences for the use of N. lobata in traditional medicine and its cultivation is discussed.

[Study on HPLC fingerprint of flavonoids from Houttuynia cordata by comparing with fingerprint reference].

PubMed

Zhang, Ting-Ting; Wu, Yi; Hang, Tai-Jun

2009-05-01

To establish a stable and repeatable HPLC fingerprint standard and evaluate the flavonoids from Houttuynia cordata qualitatively and quantitatively. HPLC separation was performed on a C18 column with methanol-0.1% phosphoric acid mixed solution as mobile phase in gradient elution mode. The fingerprint reference was determined as one of the most typical chromatograms and used to be compared with other samples through Cosine and Relative Euclid Distance methods, thus the chromatographic fingerprints of flavonoids from Houttuynia cordata were evaluated by constitutes and contents, respectively. Fourteen mutual peaks were fixed in the HPLC fingerprint of flavonoids from Houttaynia cordata. It showed good results in validation tests in which the quercitrin's peak was set as the reference peak to calculate relative retention time and area of other peaks in the chromatograms, and the RSD were less than 0.2% and 5.0%, respectively. The linear ranges for quercitrin was 1.07-83.4 microg/mL (r=0.9999) and the average recovery was 100.3%. The method shows good repeatability, ruggedness and reliability. Comparing with the established reference fingerprint, the evaluation system including Cosine and Relative Euclid Distance methods lays dependable foundation for controlling the quality of Houttuynia cordata.

Quantitative determination of ambroxol in tablets by derivative UV spectrophotometric method and HPLC.

PubMed

Dinçer, Zafer; Basan, Hasan; Göger, Nilgün Günden

2003-04-01

A derivative UV spectrophotometric method for the determination of ambroxol in tablets was developed. Determination of ambroxol in tablets was conducted by using first-order derivative UV spectrophotometric method at 255 nm (n = 5). Standards for the calibration graph ranging from 5.0 to 35.0 microg/ml were prepared from stock solution. The proposed method was accurate with 98.6+/-0.4% recovery value and precise with coefficient of variation (CV) of 1.22. These results were compared with those obtained by reference methods, zero-order UV spectrophotometric method and reversed-phase high-performance liquid chromatography (HPLC) method. A reversed-phase C(18) column with aqueous phosphate (0.01 M)-acetonitrile-glacial acetic acid (59:40:1, v/v/v) (pH 3.12) mobile phase was used and UV detector was set to 252 nm. Calibration solutions used in HPLC were ranging from 5.0 to 20.0 microg/ml. Results obtained by derivative UV spectrophotometric method was comparable to those obtained by reference methods, zero-order UV spectrophotometric method and HPLC, as far as ANOVA test, F(calculated) = 0.762 and F(theoretical) = 3.89, was concerned. Copyright 2003 Elsevier Science B.V.

Trace analysis of pollutants in water using the photothermal interferometry as HPLC detector.

PubMed

Seidel, B S; Dübel, O; Faubel, W; Ache, H J

1996-03-01

A new procedure including high performance liquid chromatography in combination with photothermal interference spectroscopy as detection device (HPLC/PIS) has been proposed, optimized and its figures of merit for pesticide residue analysis are shown. The flowing sample under study is set in one arm of a Mach-Zehnder interferometer, and its refractive index is modulated by a periodically chopped continuous wave argon ion laser. As chopper, an acousto optical modulator has been introduced to switch the excitation laser beam between different lines (457 nm, 488 nm, 514 nm) simultaneously. Thus a multi component analysis can be realized either by using an HPLC-system in front of the PIS device or by a multi line Ar(+)-laser, directly. The limit of detection of the HPLC/PIS system reached 71 microg/l of the pesticide di-nitro-ortho-cresol (DNOC).

HPLC pigment analysis of marine phytoplankton during a red tide occurrence in Tolo Harbour, Hong Kong.

PubMed

Wong, C Kwan; Wong, C Kim

2003-09-01

A red tide was detected in the inner parts of Tolo Harbour, Hong Kong, in November 2000. Water samples were collected from a fixed station at the centre of the red tide patch for microscopic analysis of phytoplankton community composition and high performance liquid chromatography (HPLC) analysis of phytoplankton pigments. At the peak of the red tide on 24 November 2000, phytoplankton was dominated by the dinoflagellate Scrippsiella trochoidea. The red tide began to decline at the end of November and, by 1 December 2000, the phytoplankton was dominated by diatoms. Chlorophylls and carotenoids in water samples were analysed using HPLC pigment separation technique. Dinoflagellates were indicated by the signature pigment peridinin. Significant correlation (r=0.999) was found between the peridinin concentration and dinoflagellate density. A decrease in peridinin and an increase in fucoxanthin, a major carotenoid in diatoms, marked the shift in phytoplankton composition at the end of the red tide. HPLC analysis also revealed the occurrence of minor phytoplankton groups that are difficult to identify by light microscopy. Red tide monitoring and study of red tide dynamics in Hong Kong have been based on cell counting and spectrophotometric or fluorometric measurement of chlorophyll a. HPLC pigment analysis provides an effective alternative for investigating phytoplankton dynamics during red tide and other algal blooms.

Two-dimensional fingerprinting approach for comparison of complex substances analysed by HPLC-UV and fluorescence detection.

PubMed

Ni, Yongnian; Liu, Ying; Kokot, Serge

2011-02-07

This work is concerned with the research and development of methodology for analysis of complex mixtures such as pharmaceutical or food samples, which contain many analytes. Variously treated samples (swill washed, fried and scorched) of the Rhizoma atractylodis macrocephalae (RAM) traditional Chinese medicine (TCM) as well as the common substitute, Rhizoma atractylodis (RA) TCM were chosen as examples for analysis. A combined data matrix of chromatographic 2-D HPLC-DAD-FLD (two-dimensional high performance liquid chromatography with diode array and fluorescence detectors) fingerprint profiles was constructed with the use of the HPLC-DAD and HPLC-FLD individual data matrices; the purpose was to collect maximum information and to interpret this complex data with the use of various chemometrics methods e.g. the rank-ordering multi-criteria decision making (MCDM) PROMETHEE and GAIA, K-nearest neighbours (KNN), partial least squares (PLS), back propagation-artificial neural networks (BP-ANN) methods. The chemometrics analysis demonstrated that the combined 2-D HPLC-DAD-FLD data matrix does indeed provide more information and facilitates better performing classification/prediction models for the analysis of such complex samples as the RAM and RA ones noted above. It is suggested that this fingerprint approach is suitable for analysis of other complex, multi-analyte substances.

Rapid and simple immunochemical screening combined with hand-shaking extraction for thiamethoxam residue in agricultural products.

PubMed

Watanabe, Eiki; Kobara, Yuso; Miyake, Shiro

2013-06-01

With the aim of expanding the applicability of a kit-based enzyme-linked immunosorbent assay (ELISA) for the neonicotinoid insecticide thiamethoxam, the ELISA was newly applied to three kinds of agricultural samples (green pepper, eggplant and spinach). To offer the ELISA as a screening analysis for thiamethoxam residues, a rapid and simple method of extraction by hand-shaking was used, and speed-up and simplification of the sample treatment before the ELISA analysis were examined. Finally, the validity of the ELISA combined with the proposed extraction method was verified against a reference high-performance liquid chromatography (HPLC) method using real-world agricultural samples. There were no marked matrix effects derived from green pepper and eggplant extracts. On the other hand, although the effect due to a pigment in spinach extract on the assay performance was significant, it was effectively avoided by increasing the dilution level of the spinach extract. For thiamethoxam-spiked samples, acceptable recoveries of 97.9-109.1% and coefficients of variation of 0.3-11.5% were obtained. Inspection of the validity of the ELISA by comparison with the reference HPLC method showed that the two analytical results were very similar, and a high correlation was found between them (r>0.997). The evaluated ELISA combined with hand-shaking extraction provided a rapid and simple screening analysis that was quantitative and reliable for the detection of thiamethoxam in complex agricultural products. © 2012 Society of Chemical Industry.

A comparison of the determination and speciation of inorganic arsenic using general HPLC methodology with UV, MS and MS/MS detection.

PubMed

Gilmartin, Gregory; Gingrich, Diane

2018-04-15

The determination and speciation of arsenic in natural resources such as drinking water and agricultural soils has been a growing concern in recent years due to its many toxicological effects [1-3]. To speciate and quantitate concentrations of <1 ppm of arsenic, typically an ion chromatograph (IC) interfaced to an inductively coupled plasma mass spectrometer (ICP-MS) is employed [4-9]. This methodology may be very robust and sensitive, but it is expensive and not as ubiquitous as high performance liquid chromatography (HPLC) with ultraviolet (UV) absorbance detection or electrospray ionization mass spectrometry (ESI-MS). Anion exchange chromatography is a well-documented means of speciating arsenite (As(III), As 2 O 3 ) and arsenate (As(V), AsO 4 ) using UV [10], conductivity [11], or ESI-MS detection [12,13]. This paper demonstrates the utilization of common liquid chromatographic instrumentation to speciate and determines inorganic Arsenic compounds using UV or MS via selected ion recording (SIR) or multiple reaction monitoring (MRM) detection. This paper describes the analysis of arsenite and arsenate samples prepared using both deionized and ground water. The limit of quantitation for the techniques described in this paper for samples spiked in ground water were 454 ppb (As(III)) and 562 ppb (As(V)) for UV detection, 45.4 ppb (As(III)) and 56.2 ppb (As(V)) for SIR detection, and 4.54 ppb (As(III)) and 5.62 ppb (As(V)) for MRM detection. Copyright © 2018 Elsevier B.V. All rights reserved.

Lysergic acid amide as chemical marker for the total ergot alkaloids in rye flour - Determination by high-performance thin-layer chromatography-fluorescence detection.

PubMed

Oellig, Claudia

2017-07-21

Ergot alkaloids are generally determined by high-performance liquid chromatography (HPLC) coupled to fluorescence detection (FLD) or mass selective detection, analyzing the individual compounds. However, fast and easy screening methods for the determination of the total ergot alkaloid content are more suitable, since for monitoring only the sum of the alkaloids is relevant. The herein presented screening uses lysergic acid amide (LSA) as chemical marker, formed from ergopeptine alkaloids, and ergometrine for the determination of the total ergot alkaloids in rye with high-performance thin-layer chromatography-fluorescence detection (HPTLC-FLD). An ammonium acetate buffered extraction step was followed by liquid-liquid partition for clean-up before the ergopeptine alkaloids were selectively transformed to LSA and analyzed by HPTLC-FLD on silica gel with isopropyl acetate/methanol/water/25% ammonium hydroxide solution (80:10:3.8:1.1, v/v/v/v) as the mobile phase. The enhanced native fluorescence of LSA and unaffected ergometrine was used for quantitation without any interfering matrix. Limits of detection and quantitation were 8 and 26μg LSA/kg rye, which enables the determination of the total ergot alkaloids far below the applied quality criterion limit for rye. Close to 100% recoveries for different rye flours at relevant spiking levels were obtained. Thus, reliable results were guaranteed, and the fast and efficient screening for the total ergot alkaloids in rye offers a rapid alternative to the HPLC analysis of the individual compounds. Copyright © 2017 Elsevier B.V. All rights reserved.

Quantitative determination and sampling of azathioprine residues for cleaning validation in production area.

PubMed

Fazio, Tatiana Tatit; Singh, Anil Kumar; Kedor-Hackmann, Erika Rosa Maria; Santoro, Maria Inês Rocha Miritello

2007-03-12

Cleaning validation is an integral part of current good manufacturing practices in any pharmaceutical industry. Nowadays, azathioprine and several other pharmacologically potent pharmaceuticals are manufactured in same production area. Carefully designed cleaning validation and its evaluation can ensure that residues of azathioprine will not carry over and cross contaminate the subsequent product. The aim of this study was to validate simple analytical method for verification of residual azathioprine in equipments used in the production area and to confirm efficiency of cleaning procedure. The HPLC method was validated on a LC system using Nova-Pak C18 (3.9 mm x 150 mm, 4 microm) and methanol-water-acetic acid (20:80:1, v/v/v) as mobile phase at a flow rate of 1.0 mL min(-1). UV detection was made at 280 nm. The calibration curve was linear over a concentration range from 2.0 to 22.0 microg mL(-1) with a correlation coefficient of 0.9998. The detection limit (DL) and quantitation limit (QL) were 0.09 and 0.29 microg mL(-1), respectively. The intra-day and inter-day precision expressed as relative standard deviation (R.S.D.) were below 2.0%. The mean recovery of method was 99.19%. The mean extraction-recovery from manufacturing equipments was 83.5%. The developed UV spectrophotometric method could only be used as limit method to qualify or reject cleaning procedure in production area. Nevertheless, the simplicity of spectrophotometric method makes it useful for routine analysis of azathioprine residues on cleaned surface and as an alternative to proposed HPLC method.

Towards a semiquantitative non invasive characterisation of Tyrian purple dye composition: Convergence of UV-Visible reflectance spectroscopy and fast-high temperature-high performance liquid chromatography with photodiode array detection.

PubMed

Clementi, Catia; Nowik, Witold; Romani, Aldo; Cardon, Dominique; Trojanowicz, Marek; Davantès, Athénaïs; Chaminade, Pierre

2016-07-05

In this paper, partial least square (PLS) regression is innovatively applied for a semi-quantitative non invasive study of the most precious dye of Antiquity: Tyrian purple. This original approach for the study of organic dyes in the cultural heritage field, is based on the correlation of spectrophotometric (UV-Visible) and chromatographic (Fast-HT-HPLC-PDA) data from an extensive set of textiles prepared with different snail species according to historical recipes. A cross-validated PLS model, based on the quantity of 6,6'-dibromoindigotin, displays an excellent correlation factor (R(2)Y = 0.987) between values determined by chromatography and those predicted from reflectance spectra. This indicates that the spectral features of Tyrian purple on textile fibre is strictly related to the amount of this indigoid component whose content may be non invasively predicted from reflectance spectrum. The studied correlation also highlights that, independently of the dyeing method and nature of the textile fibre used, the relative content of 6,6'-dibromindigotin may be used as a parameter to distinguish samples prepared with Hexaplex trunculus L. snails from those prepared with further mollusc species. To validate this model, archaeological textile fragments dating from the Roman period were successfully examined. The results achieved open an absolutely new way in Tyrian purple analysis in cultural heritage by non invasive spectroscopic techniques attesting their convergence with HPLC and giving them a semi-quantitative value. Copyright © 2016 Elsevier B.V. All rights reserved.

Novel Pathways of Nitroaromatic Metabolism: Hydroxylamine Formation, Reactivity and Potential for Ring Fission for Destruction of TNT-CU1214

DTIC Science & Technology

2005-08-15

phase was terminated when HPLC analysis showed that the initial TNT was in the form of DHA6NT and aminophenols , products that have been reported...terminated when HPLC analysis showed that the initial TNT was in the form of DHA6NT and aminophenols , products that have been reported previously (2...Department of Defense HPLC High Performance Liquid Chromatography IPTG Isopropyl-β-D-1-thiogalactopyranoside LB Luria-Bertani Broth NB Nitrobenzene

Fingerprint chromatogram analysis of Pseudostellaria heterophylla (Miq.) Pax root by high performance liquid chromatography.

PubMed

Han, Chao; Chen, Junhui; Chen, Bo; Lee, Frank Sen-Chun; Wang, Xiaoru

2006-09-01

A simple and reliable high performance liquid chromatographic (HPLC) method has been developed and validated for the fingerprinting of extracts from the root of Pseudostellaria heterophylla (Miq.) Pax. HPLC with gradient elution was performed on an authentic reference standard of powdered P. heterophylla (Miq.) Pax root and 11 plant samples of the root were collected from different geographic locations. The HPLC chromatograms have been standardized through the selection and identification of reference peaks and the normalization of retention times and peak intensities of all the common peaks. The standardized HPLC fingerprints show high stability and reproducibility, and thus can be used effectively for the screening analysis or quality assessment of the root or its derived products. Similarity index calculations based on cosine angle values or correlation methods have been performed on the HPLC fingerprints. As a group, the fingerprints of the P. heterophylla (Miq.) Pax samples studied are highly correlated with closely similar fingerprints. Within the group, the samples can be further divided into subgroups based on hierarchical clustering analysis (HCA). Sample grouping based on HCA coincides nicely with those based on the geographical origins of the samples. The HPLC fingerprinting techniques thus have high potential in authentication or source-tracing types of applications.

Comparison of transferrin isoform analysis by capillary electrophoresis and HPLC for screening congenital disorders of glycosylation.

PubMed

Dave, Mihika B; Dherai, Alpa J; Udani, Vrajesh P; Hegde, Anaita U; Desai, Neelu A; Ashavaid, Tester F

2018-01-01

Transferrin, a major glycoprotein has different isoforms depending on the number of sialic acid residues present on its oligosaccharide chain. Genetic variants of transferrin as well as the primary (CDG) & secondary glycosylation defects lead to an altered transferrin pattern. Isoform analysis methods are based on charge/mass variations. We aimed to compare the performance of commercially available capillary electrophoresis CDT kit for diagnosing congenital disorders of glycosylation with our in-house optimized HPLC method for transferrin isoform analysis. The isoform pattern of 30 healthy controls & 50 CDG-suspected patients was determined by CE using a Carbohydrate-Deficient Transferrin kit. The results were compared with in-house HPLC-based assay for transferrin isoforms. Transferrin isoform pattern for healthy individuals showed a predominant tetrasialo transferrin fraction followed by pentasialo, trisialo, and disialotransferrin. Two of 50 CDG-suspected patients showed the presence of asialylated isoforms. The results were comparable with isoform pattern obtained by HPLC. The commercial controls showed a <20% CV for each isoform. Bland Altman plot showed the difference plot to be within +1.96 with no systemic bias in the test results by HPLC & CE. The CE method is rapid, reproducible and comparable with HPLC and can be used for screening Glycosylation defects. © 2017 Wiley Periodicals, Inc.

Honey with Psilocybe mushrooms: a revival of a very old preparation on the drug market?

PubMed

Bogusz, M J; Maier, R D; Schäfer, A T; Erkens, M

1998-01-01

In 1996 samples of suspicious honey preparations were confiscated at the Dutch-German border. The labels on the 50 ml jars indicated that the honey contained Stropharia cubensis (better known as Psilocybe cubensis). The jars were filled with honey with a ca. 1 cm layer of fine particles on the top. The particles were collected and subjected to microscopic and chemical analysis. By microscopy mushroom tissue (plectenchym) and spores typical for the genus Psilocybe were identified in all samples. The HPLC analysis with atmospheric pressure mass spectrometry and diode array detection revealed psilocine but psilocybine was not found. The quantitative analysis was very difficult due to the matrix problems. A search showed that the honey with Psilocybe can be purchased in Dutch coffee shops without any limitations although psilocine and psilocybine belong to listed substances according to Dutch law.

Increased concentrations of endogenous 13-cis- and all-trans-retinoic acids in diffuse idiopathic skeletal hyperostosis, as demonstrated by HPLC.

PubMed

Periquet, B; Lambert, W; Garcia, J; Lecomte, G; De Leenheer, A P; Mazieres, B; Thouvenot, J P; Arlet, J

1991-11-09

Endogenous 13-cis- and all-trans-retinoic acids have been quantitated in human serum using a solvent extraction procedure followed by isocratic reversed phase high performance liquid chromatography and UV detection. In healthy adults, after an overnight fasting period, the concentrations of 13-cis- and all-trans-retinoic acids yielded 5.3 +/- 2.43 nmol/l and 11.8 +/- 3.3 nmol/l, respectively (mean +/- SD). The method has been successfully applied to the analysis of both isomers in serum from patients with idiopathic skeletal hyperostosis in whom, the 13-cis- as well as all-trans-retinoic acid levels were raised as compared to the control group.

HPLC-PFD determination of priority pollutant PAHs in water, sediment, and semipermeable membrane devices

USGS Publications Warehouse

Williamson, K.S.; Petty, J.D.; Huckins, J.N.; Lebo, J.A.; Kaiser, E.M.

2002-01-01

High performance liquid chromatography coupled with programmable fluorescence detection was employed for the determination of 15 priority pollutant polycyclic aromatic hydrocarbons (PPPAHs) in water, sediment, and semipermeable membrane devices (SPMDs). Chromatographic separation using this analytical method facilitates selectivity, sensitivity (ppt levels), and can serve as a non-destructive technique for subsequent analysis by other chromatographic and spectroscopic techniques. Extraction and sample cleanup procedures were also developed for water, sediment, and SPMDs using various chromatographic and wet chemical methods. The focus of this publication is to examine the enrichment techniques and the analytical methodologies used in the isolation, characterization, and quantitation of 15 PPPAHs in different sample matrices.

Application of curve resolution algorithms in the study of drug photodegradation kinetics -- the example of moclobemide.

PubMed

Skibiński, Robert; Komsta, Łukasz

2012-01-01

The photodegradation of moclobemide was studied in methanolic media. Ultra-HPLC (UHPLC)/MS/MS analysis proved decomposition to 4-chlorobenzamide as a major degradation product and small amounts of Ro 16-3177 (4-chloro-N-[2-[(2-hydroxyethyl)amino] ethyl]benzamide) and 2-[(4-chlorobenzylidene)amino]-N-[2-ethoxyethenyl]ethenamine. The methanolic solution was investigated spectrophotometrically in the UV region, registering the spectra during 30 min of degradation. Using reference spectra and a multivariate chemometric method (multivariate curve resolution-alternating least squares), the spectra were resolved and concentration profiles were obtained. The obtained results were in good agreement with a quantitative approach, with UHPLC-diode array detection as the reference method.

Root Cause Analysis of Quality Defects Using HPLC-MS Fingerprint Knowledgebase for Batch-to-batch Quality Control of Herbal Drugs.

PubMed

Yan, Binjun; Fang, Zhonghua; Shen, Lijuan; Qu, Haibin

2015-01-01

The batch-to-batch quality consistency of herbal drugs has always been an important issue. To propose a methodology for batch-to-batch quality control based on HPLC-MS fingerprints and process knowledgebase. The extraction process of Compound E-jiao Oral Liquid was taken as a case study. After establishing the HPLC-MS fingerprint analysis method, the fingerprints of the extract solutions produced under normal and abnormal operation conditions were obtained. Multivariate statistical models were built for fault detection and a discriminant analysis model was built using the probabilistic discriminant partial-least-squares method for fault diagnosis. Based on multivariate statistical analysis, process knowledge was acquired and the cause-effect relationship between process deviations and quality defects was revealed. The quality defects were detected successfully by multivariate statistical control charts and the type of process deviations were diagnosed correctly by discriminant analysis. This work has demonstrated the benefits of combining HPLC-MS fingerprints, process knowledge and multivariate analysis for the quality control of herbal drugs. Copyright © 2015 John Wiley & Sons, Ltd.

Combination of Liquid Chromatography with Multivariate Curve Resolution-Alternating Least-Squares (MCR-ALS) in the Quantitation of Polycyclic Aromatic Hydrocarbons Present in Paprika Samples.

PubMed

Monago-Maraña, Olga; Pérez, Rocío L; Escandar, Graciela M; Muñoz de la Peña, Arsenio; Galeano-Díaz, Teresa

2016-11-02

This work presents a strategy for quantitating polycyclic aromatic hydrocarbons (PAHs) in smoked paprika samples. For this, a liquid chromatographic method with fluorimetric detection (HPLC-FLD) was optimized. To resolve some interference co-eluting with the target analytes, the second-order multivariate curve resolution-alternating least-squares (MCR-ALS) algorithm has been employed combined with this liquid chromatographic method. Among the eight PAHs quantified (fluorene, phenanthrene, anthracene, pyrene, chrysene, benzo[a]anthracene, benzo[b]fluoranthene, and benzo[a]pyrene) by HPLC-FLD, only in the case of fluorene, pyrene, and benzo[b]fluoranthene was it necessary to apply the second-order algorithm for their resolution. Limits of detection and quantitation were between 0.015 and 0.45 mg/kg and between 0.15 and 1.5 mg/kg, respectively. Good recovery results (>80%) for paprika were obtained via the complete extraction procedure, consisting of an extraction from the matrix and the cleanup of the extract by means of silica cartridges. Higher concentrations of chrysene, benzo[a]anthracene, benzo[b]fluoranthene, and benzo[a]pyrene were found in the paprika samples, with respect to the maximal amounts allowed for other spices that are under European Regulation (EU) N° 2015/1933.

[HPLC specific chromatogram of Lamiophlomis Herba and its counterfeit and determination of four effective components].

PubMed

Zan, Ke; Jiao, Xing-Ping; Guo, Li-Nong; Zheng, Jian; Ma, Shuang-Cheng

2016-06-01

This study is to establish the HPLC specific chromatogram and determine four main effective components of Lamiophlomis Herba and its counterfeit.Chlorogenic acid, forsythoside B, acteoside and luteoloside were reference substance.HPLC analysis was performed on a Waters XSelect C₁₈ column (4.6 mm×250 mm,5 μm).The mobile phase was acetonitrile-0.5% phosphoric acid solution (18∶82) with isocratic elution.The flow rate was 1.0 mL•min⁻¹, the detection wavelength was 332 nm and the column temperature was 30 ℃.Chemometrics software Chempattern was employed to analyze the research data.HPLC specific chromatogram of Lamiophlomis Herba from different samples were of high similarity, but the similarity of the HPLC specific chromatogram of its counterfeit were less than 0.65.Both of cluster and principal component analysis can distinguish certified products and adulterants.The HPLC specific chromatogram and contents of four effective components can be used for the quality control of Lamiophlomis Herba and its preparations.It provided scientific basis to standardize the use of the crude drug. Copyright© by the Chinese Pharmaceutical Association.

Major and Modified Nucleosides, RNA, and DNA

NASA Astrophysics Data System (ADS)

Gehrke, Charles W.; Kuo, Kenneth C.

Most analytical chemists are well aware of the rapid rate of development of high-performance liquid chromatography (HPLC) over the past 5 years. A number of articles have been published in Analytical Chemistry on different topics in HPLC and many papers appear in the chromatographic journals. Some books also have been published covering this subject. HPLC has proved to be a very effective, broadly applicable chromatographic method for the separation and analysis of complex molecules in fields as diverse as biochemistry and environmental, pharmaceutical, medical, and polymer chemistry. HPLC is now having a major impact on the clinical and research aspects of medical biochemistry. Although the contributions of HPLC to other disciplines generally complements gas-liquid chromatography, this method is destined to play a much greater role in medical and biochemical research. This is because many of the biomolecules, owing to their molecular complexity and size, are thermally unstable or nonvolatile, preventing or complicating an analysis by GC. A major factor contributing to the powerful advances in biomedical liquid chromatography is the development of reversed-phase high-performance liquid chromatography (RP-HPLC) using n-alkyl and phenyl chemically bonded substrates.

Quantitative determination of decursin, decursinol angelate, and decursinol in mouse plasma and tumor tissue using liquid-liquid extraction and HPLC.

PubMed

Li, Li; Zhang, Jinhui; Shaik, Ahmad Ali; Zhang, Yong; Wang, Lei; Xing, Chengguo; Kim, Sung-Hoon; Lü, Junxuan

2012-02-01

The pyranocoumarin compound decursin and its isomer decursinol angelate (DA) are the major hydrophobic phytochemicals in the root of Angelica gigas Nakai (AGN, Korean Angelica), a major traditional medicinal herb. The ethanol extract of AGN and especially the purified decursin and DA have been shown to exhibit antitumor activities by our collaborative team and others. Although decursinol has been identified as a major hydrolysis metabolite of decursin and DA in vivo in previous pharmacokinetic studies with mouse and rat, other recently published results sharply disputed this conclusion. In this study, we set up a practical method for the concurrent analysis of decursin, DA, and decursinol in mouse plasma and tumor tissues by liquid-liquid extraction and HPLC-UV and applied the method to several animal experiments. Plasma or tumor homogenate was extracted directly with ethyl acetate. The extraction efficiency for decursin/DA (quantitated together) and decursinol was between 82-95 % in both mouse plasma and tumor homogenate. The lower limit of quantitation (LLOQ) was approximately 0.25 µg/mL for decursin/DA and 0.2 µg/mL for decursinol in mouse plasma. In a pilot pharmacokinetic study, male C57BL/6 mice were given a single dose of 4.8 mg decursin/DA mixture (~240 mg/kg) per mouse either by oral gavage or intraperitoneal injection. Maximum plasma concentrations for decursin/DA and decursinol were 11.2 and 79.7 µg/mL, respectively, when decursin/DA was administered via intraperitoneal injection, and 0.54 and 14.9 µg/mL via oral gavage. Decursin/DA and decursinol contents in the tumor tissues from nude mouse xenografts correlated very well with those in plasma. Overall, our results confirm the conclusion that the majority of decursin/DA hydrolyze to decursinol in rodent models with a tiny fraction remaining as the intact compounds administered. © Georg Thieme Verlag KG Stuttgart · New York.

Enantioselective quantitation of the ecstasy compound (R)- and (S)-N-ethyl-3,4-methylenedioxyamphetamine and its major metabolites in human plasma and urine.

PubMed

Buechler, Jochen; Schwab, Matthias; Mikus, Gerd; Fischer, Beate; Hermle, Leo; Marx, Claudia; Grön, Georg; Spitzer, Manfred; Kovar, Karl Artur

2003-08-15

An enantioselective HPLC method has been developed and validated for the stereospecific analysis of N-ethyl-3,4-methylenedioxyamphetamine (MDE) and its major metabolites N-ethyl-4-hydroxy-3-methoxyamphetamine (HME) and 3,4-methylenedioxyamphetamine (MDA). These compounds have been analyzed both from human plasma and urine after administration of 70 mg pure MDE-hydrochloride enantiomers to four subjects. The samples were prepared by hydrolysis of the o-glucuronate and sulfate conjugates using beta-glucuronidase/arylsulfatase and solid-phase extraction with a cation-exchange phase. A chiral stationary protein phase (chiral-CBH) was used for the stereoselective determination of MDE, HME and MDA in a single HPLC run using sodium dihydrogenphosphate, ethylendiaminetetraacetic acid disodium salt and isopropanol as the mobile phase (pH 6.44) and fluorimetric detection (lambda(ex) 286 nm, lambda(em) 322 nm). Moreover, a suitable internal standard (N-ethyl-3,4-methylenedioxybenzylamine) was synthesized and qualified for quantitation purposes. The method showed high recovery rates (>95%) and limits of quantitation for MDE and MDA of 5 ng/ml and for HME of 10 ng/ml. The RSDs for all working ranges of MDE, MDA and HME in plasma and urine, respectively, were less than 1.5%. After validation of the analytical methods in plasma and urine samples pharmacokinetic parameters were calculated. The plasma concentrations of (R)-MDE exceeded those of the S-enantiomer (ratio R:S of the area under the curve, 3.1) and the plasma half time of (R)-MDE was longer than that of (S)-MDE (7.9 vs. 4.0 h). In contrast, the stereochemical disposition of the MDE metabolites HME and MDA was reversed. Concentrations of the (S)-metabolites in plasma of volunteers were much higher than those of the (R)-enantiomers.

[Matrix effect and application of field-amplified sample injection in the analysis of four tetracyclines in waters by capillary electrohoresis].

PubMed

2014-08-01

The system abilities of two chromatographic techniques, capillary electrophoresis (CE) and high performance liquid chromatography (HPLC), were compared for the analysis of four tetracyclines (tetracycline, chlorotetracycline, oxytetracycline and doxycycline). The pH, concentration of background electrolyte (BGE) were optimized for the analysis of the standard mixture sample, meanwhile, the effects of separation voltage and water matrix (pH value and hardness) effects were investigated. In hydrodynamic injection (HDI) mode, a good quantitative linearity and baseline separation within 9. 0 min were obtained for the four tetracyclines at the optimal conditions; the analytical time was about half of that of HPLC. The limits of detection (LODs) were in the range of 0. 28 - 0. 62 mg/L, and the relative standard deviations (RSDs) (n= 6) of migration time and peak area were 0. 42% - 0. 56% and 2. 24% - 2. 95%, respectively. The obtained recoveries spiked in tap water and fishpond water were at the ranges of 96. 3% - 107. 2% and 87. 1% - 105. 2%, respectively. In addition, the stacking method, field-amplified sample injection (FASI), was employed to improve the sensitivity, and the LOD was down to the range of 17.8-35.5 μg/L. With FASI stacking, the RSDs (n=6) of migration time and peak area were 0. 85%-0. 95% and 1. 69%-3.43%, respectively. Due to the advantages of simple sample pretreatment and fast speed, CE is promising in the analysis of the antibiotics in environmental water.

High-speed counter-current chromatography coupled online to high performance liquid chromatography-diode array detector-mass spectrometry for purification, analysis and identification of target compounds from natural products.

PubMed

Liang, Xuejuan; Zhang, Yuping; Chen, Wei; Cai, Ping; Zhang, Shuihan; Chen, Xiaoqin; Shi, Shuyun

2015-03-13

A challenge in coupling high-speed counter-current chromatography (HSCCC) online with high performance liquid chromatography (HPLC) for purity analysis was their time incompatibility. Consequently, HSCCC-HPLC was conducted by either controlling HPLC analysis time and HSCCC flow rate or using stop-and-go scheme. For natural products containing compounds with a wide range of polarities, the former would optimize experimental conditions, while the latter required more time. Here, a novel HSCCC-HPLC-diode array detector-mass spectrometry (HSCCC-HPLC-DAD-MS) was developed for undisrupted purification, analysis and identification of multi-compounds from natural products. Two six-port injection valves and a six-port switching valve were used as interface for collecting key HSCCC effluents alternatively for HPLC-DAD-MS analysis and identification. The ethyl acetate extract of Malus doumeri was performed on the hyphenated system to verify its efficacy. Five main flavonoids, 3-hydroxyphloridzin (1), phloridzin (2), 4',6'-dihydroxyhydrochalcone-2'-O-β-D-glucopyranoside (3, first found in M. doumeri), phloretin (4), and chrysin (5), were purified with purities over 99% by extrusion elution and/or stepwise elution mode in two-step HSCCC, and 25mM ammonium acetate solution was selected instead of water to depress emulsification in the first HSCCC. The online system shortened manipulation time largely compared with off-line analysis procedure and stop-and-go scheme. The results indicated that the present method could serve as a simple, rapid and effective way to achieve target compounds with high purity from natural products. Copyright © 2015 Elsevier B.V. All rights reserved.

Enantioselective determination of metoprolol and its metabolites in human urine high-performance liquid chromatography with fluorescence detection (HPLC-FLD) and tandem mass spectrometry (MS/MS).

PubMed

Baranowska, Irena; Adolf, Weronika; Magiera, Sylwia

2015-11-01

A sensitive, stereoselective assay using solid phase extraction and high-performance liquid chromatography (HPLC) with fluorescence detection (FLD) was developed and validated for the analysis of enantiomers of metoprolol and its metabolites (α-hydroxymetoprolol, O-desmethylmetoprolol). Chiral separation was achieved using a CHIRALCEL OD-RH column, packed with cellulose tris-(3,5-dimethylphenyl-carbamate) stationary phase, employing a mobile phase composed by a mixture of 0.2% diethylamine in water and acetonitrile in gradient elution mode. Linear calibration curves were obtained over the range of 0.025-2.0μg/mL (R(2)>0.994) in urine for both enantiomers of metoprolol and its metabolites with quantitation limit of 0.025μg/mL. Intra and inter-day precision and accuracy were below 15% for both metoprolol and metabolites enantiomers. The recovery of enantiomer of metoprolol and its metabolite was greater than 68.0%, utilizing a SPE procedure. The method was tested with urine quality control samples and human urine fractions after administration of 50mg rac-metoprolol. Copyright © 2015 Elsevier B.V. All rights reserved.

Phenolic profiles in leaves of chicory cultivars (Cichorium intybus L.) as influenced by organic and mineral fertilizers.

PubMed

Sinkovič, Lovro; Demšar, Lea; Žnidarčič, Dragan; Vidrih, Rajko; Hribar, Janez; Treutter, Dieter

2015-01-01

Chicory (Cichorium intybus L.) is a typical Mediterranean vegetable, and it shows great morphological diversity, including different leaf colours. Five cultivars commonly produced in Slovenia ('Treviso', 'Verona', 'Anivip', 'Castelfranco', 'Monivip') were grown in pots under controlled conditions in a glasshouse, with organic and/or mineral fertilizers administered to meet nitrogen requirements. HPLC analysis was carried out to study the phenolic compositions of the leaves. A total of 33 phenolic compounds were extracted from these chicory leaves and were quantitatively evaluated in an HPLC-DAD-based metabolomics study. Among the cultivars, the highest TPC was seen for 'Treviso' (300.1 mg/100 g FW), and the lowest, for 'Castelfranco' (124.9 mg/100g FW). Across the different treatments, the highest TPC was in the control samples (254.3 mg/100 g FW), and the lowest for the organic (128.6 mg/100 g FW) and mineral fertilizer (125.5 mg/100 g FW) treatments. The predominant phenolic compounds in all of the samples were hydroxycinnamic acids, including chlorogenic and cichoric acid. Fertilizer administration provides a discriminant classification of the chicory cultivars according to their phenolic compounds. Copyright © 2014 Elsevier Ltd. All rights reserved.

Application of multibounce attenuated total reflectance fourier transform infrared spectroscopy and chemometrics for determination of aspartame in soft drinks.

PubMed

Khurana, Harpreet Kaur; Cho, Il Kyu; Shim, Jae Yong; Li, Qing X; Jun, Soojin

2008-02-13

Aspartame is a low-calorie sweetener commonly used in soft drinks; however, the maximum usage dose is limited by the U.S. Food and Drug Administration. Fourier transform infrared (FTIR) spectroscopy with attenuated total reflectance sampling accessory and partial least-squares regression (PLS) was used for rapid determination of aspartame in soft drinks. On the basis of spectral characterization, the highest R2 value, and lowest PRESS value, the spectral region between 1600 and 1900 cm(-1) was selected for quantitative estimation of aspartame. The potential of FTIR spectroscopy for aspartame quantification was examined and validated by the conventional HPLC method. Using the FTIR method, aspartame contents in four selected carbonated diet soft drinks were found to average from 0.43 to 0.50 mg/mL with prediction errors ranging from 2.4 to 5.7% when compared with HPLC measurements. The developed method also showed a high degree of accuracy because real samples were used for calibration, thus minimizing potential interference errors. The FTIR method developed can be suitably used for routine quality control analysis of aspartame in the beverage-manufacturing sector.

Determination of simazine in water samples by HPLC after preconcentration with diatomaceous earth.

PubMed

Katsumata, Hideyuki; Fujii, Aya; Kaneco, Satoshi; Suzuki, Tohru; Ohta, Kiyohisa

2005-01-15

A sensitive and selective batch adsorption method is proposed for the preconcentration and determination of simazine. Simazine was preconcentrated on diatomaceous earth as an adsorbent and then determined by high-performance liquid chromatography (HPLC). Several parameters on the recovery of the analyte were investigated. The experimental results showed that it was possible to obtain quantitative analysis when the solution pH was 2 using 100mL of validation solution containing 1.5mug of simazine and 5mL of ethanol as an eluent. Recovery of simazine was 89.0 +/- 1.6% with a relative standard deviation for seven determinations of 1.5% under optimum conditions. The maximum preconcentration factor was 100 for simazine when 500mL of sample solution volume was used. The linear range of calibration curve was 1-200ngmL(-1) with a correlation coefficient of 0.996 and the detection limit (3S/N) was 0.3ngmL(-1). The capacity of the adsorbent was also examined and found to be 1.1mgg(-1) for simazine. The proposed method was successfully applied to the determination of simazine in river water with high precision and accuracy.

Drug monitoring: simultaneous analysis of lamotrigine, oxcarbazepine, 10-hydroxycarbazepine, and zonisamide by HPLC-UV and a rapid GC method using a nitrogen-phosphorus detector for levetiracetam

PubMed Central

Greiner-Sosanko, Elizabeth; Giannoutsos, Spiros; Lower, Darla R.; Virji, Mohamed A.; Krasowski, Matthew D.

2008-01-01

A high-performance liquid chromatography (HPLC) assay using ultraviolet detection is described for the simultaneous measurement of the newer generation anti-epileptic medications lamotrigine, oxcarbazepine (parent drug and active metabolite 10-hydroxycarbazepine), and zonisamide. Detection of all four compounds can be done at 230 nm; however, there is a potential interference with zonisamide in patients on clonazepam therapy. Therefore, the method uses dual wavelength detection: 230 nm for oxcarbazepine and 10-hydroxycarbazepine and 270 nm for lamotrigine and zonisamide. In addition, a simple gas chromatography method using a nitrogen-phosphorus detector is described for measurement of levetiracetam, another of the recently approved anti-epileptic medications. For both methods, limits of quantitation, linearities, accuracies, and imprecisions cover the therapeutic range for drug monitoring of patients. A wide variety of clinical drugs, including other anti-epileptic drugs, do not interfere with these assays. These procedures would be of special interest to clinical laboratories, particularly due to the limited availability of immunoassays for newer generation anti-epileptic medications and that therapeutic uses of these drugs are expanding beyond epilepsy to other neurologic and psychiatric disorders. PMID:17988451

Medicinal cannabis: Principal cannabinoids concentration and their stability evaluated by a high performance liquid chromatography coupled to diode array and quadrupole time of flight mass spectrometry method.

PubMed

Citti, Cinzia; Ciccarella, Giuseppe; Braghiroli, Daniela; Parenti, Carlo; Vandelli, Maria Angela; Cannazza, Giuseppe

2016-09-05

In the last few years, there has been a boost in the use of cannabis-based extracts for medicinal purposes, although their preparation procedure has not been standardized but rather decided by the individual pharmacists. The present work describes the development of a simple and rapid high performance liquid chromatography method with UV detection (HPLC-UV) for the qualitative and quantitative determination of the principal cannabinoids (CBD-A, CBD, CBN, THC and THC-A) that could be applied to all cannabis-based medicinal extracts (CMEs) and easily performed by a pharmacist. In order to evaluate the identity and purity of the analytes, a high-resolution mass spectrometry (HPLC-ESI-QTOF) analysis was also carried out. Full method validation has been performed in terms of specificity, selectivity, linearity, recovery, dilution integrity and thermal stability. Moreover, the influence of the solvent (ethyl alcohol and olive oil) was evaluated on cannabinoids degradation rate. An alternative extraction method has then been proposed in order to preserve cannabis monoterpene component in final CMEs. Copyright © 2016 Elsevier B.V. All rights reserved.

Identification of the urinary metabolites of 4-bromoaniline and 4-bromo-[carbonyl-13C]-acetanilide in rat.

PubMed

Scarfe, G B; Nicholson, J K; Lindon, J C; Wilson, I D; Taylor, S; Clayton, E; Wright, B

2002-04-01

1. The urinary excretion of 4-bromoaniline and its [carbonyl-(13)C]-labelled N-acetanilide, together with their corresponding metabolites, have been investigated in the rat following i.p. administration at 50 mg kg(-1). 2. Metabolite profiling was performed by reversed-phase HPLC with UV detection, whilst identification was performed using a combination of enzymic hydrolysis and directly coupled HPLC-NMR-MS analysis. The urinary metabolite profile was quantitatively and qualitatively similar for both compounds with little of either excreted unchanged. 3. The major metabolite present in urine was 2-amino-5-bromophenylsulphate, but, in addition, a number of metabolites with modification of the N-acetyl moiety were identified (from both the [(13)C]-acetanilide or produced following acetylation of the free bromoaniline). 4. For 4-bromoacetanilide, N-deacetylation was a major route of metabolism, but despite the detection of the acetanilide following the administration of the free aniline, there was no evidence of reacetylation (futile deacetylation). 5. Metabolites resulting from the oxidation of the acetyl group included a novel glucuronide of an N-glycolanilide, an unusual N-oxanilic acid and a novel N-acetyl cysteine conjugate.

Evaluation of the recently reported USP gradient HPLC method for analysis of anti-tuberculosis drugs for its ability to resolve degradation products of rifampicin.

PubMed

Mohan, Bhavika; Sharda, Nishi; Singh, Saranjit

2003-03-10

The recently notified USP gradient HPLC method for quantitative determination of rifampicin, isoniazid and pyrazinamide in fixed dose combination (FDC) formulations was evaluated to determine its ability to resolve major degradation products of rifampicin, viz. 3-formylrifamycin SV, rifampicin N-oxide, 25-desacetyl rifampicin, rifampicin quinone, and the newly reported isonicotinyl hydrazone, an interaction product of 3-formylrifamycin and isoniazid. The first observation was that the requirements of theoretical plates listed in the given method were met for rifampicin, but not for isoniazid and pyrazinamide, even on columns of different makes. The resolving power of the method was also dependent upon make of the column. On two of the three columns of the three tested, it was able to resolve most degradation products, except rifampicin N-oxide and 25-desacetylrifampicin, which were overlapping. The method was modified and an overall satisfactory resolution for all components was obtained by changing the buffer: organic modifier ratio of solution B in the gradient from 45:55 to 55:45 and decreasing the flow rate from 1.5 to 1.0 ml/min, keeping all other conditions constant.

Polyfluoroalkyl chemicals in house dust

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kato, Kayoko; Calafat, Antonia M., E-mail: acalafat@cdc.gov; Needham, Larry L.

2009-07-15

We developed a high throughput analytical method using on-line solid phase extraction coupled with isotope dilution high-performance liquid chromatography-tandem mass spectrometry (on-line SPE-HPLC-MS/MS) to simultaneously determine the concentrations of 17 polyfluoroalkyl chemicals (PFCs) in house dust. The sample preparation includes dispersion of the dust samples in 0.1 M formic acid:MeOH (1:1), followed by agitation and filtration, addition of the isotope-labeled internal standard solution to the filtrate, and analysis by on-line SPE-HPLC-MS/MS. The limits of quantitation were <4.0 ng/g. The method accuracies ranged between 73.2% and 100.2% for the different analytes at two spike levels. We confirmed the validity of themore » method by analyzing 39 household dust samples collected in 2004. Of the 17 PFCs measured, 6 of them-perfluorobutane sulfonate (PFBuS), N-ethyl-perfluorooctane sulfonamide, 2-(N-ethyl-perfluorooctane sulfonamido) acetic acid (Et-PFOSA-AcOH), 2-(N-methyl-perfluorooctane sulfonamido) ethanol (Me-PFOSA-EtOH), perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS)-had detection frequencies >70%. We detected PFOS, PFBuS, and PFHxS at the highest median concentration, followed by Et-PFOSA-AcOH and Me-PFOSA-EtOH.« less

HPLC-Fingerprints and Antioxidant Constituents of Phyla nodiflora

PubMed Central

Yen, Feng-Lin; Chen, Pei-Chun; Wang, Moo-Chin; Lin, Chun-Nan; Lee, Chiang-Wen; Ko, Horng-Huey

2014-01-01

Phyla nodiflora is a creeping perennial herb, widely distributed in the most tropical and subtropical regions. It has been used as a folk medicine, herbal beverage, or folk cosmetic. For these usages, the development of a chemical quality control method of this plant is necessary. In the present study, ten compounds, namely, 3,7,4′,5′-tetrahydroxy-3′-methoxyflavone (1), nodifloretin (2), 4′-hydroxywogonin (3), onopordin (4), cirsiliol (5), 5,7,8,4′-tetrahydroxy-3′-methoxyflavone (6), eupafolin (7), hispidulin (8), larycitrin (9), and β-sitosterol were isolated from the methanolic extract of the aerial part of P. nodiflora (PNM) and their structures were identified by 1D-NMR comparing their spectra with the literature. The antioxidant activities of these compounds were evaluated by free radical scavenging activity and tyrosinase inhibitory effect in cell-free systems. Compounds 4, 5, and 7 showed strong antioxidant activity. To control the quality of P. nodiflora, a simple and reliable method of high-performance liquid chromatography combined with ultraviolet detector (HPLC-UV) was established for both the fingerprint analysis and the quantitative determination of two selected active compounds, onopordin (4) and eupafolin (7). Statistical analysis of the obtained data demonstrated that our method achieved the desired linearity, precision, and accuracy. The results indicated that the developed method can be used as a quality evaluation method for PNM. PMID:25140335

Determination of imidazoline and amido-amine type corrosion inhibitors in both crude oil and produced brine from oilfield production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matherly, R.M.; Jiao, J.; Blumer, D.J.

1995-12-01

The classical method for the determination of corrosion inhibitors in oilfield brines is the dye transfer method. Within this method are many variations which the analyst may use to determine the amount of corrosion inhibitor in either water or crude oil. These methods, however, suffer from many interferences which result in both false positive and negatives for corrosion inhibitor content. These methods essentially detect all amines as corrosion inhibitors. Improved high pressure liquid chromatography (HPLC) methods have been developed for the analysis of quaternary salt type corrosion inhibitors in brine waters, however, these methods do not appear to work inmore » crude oil or for other forms of corrosion inhibitors such as the imidazolines, and amido-amines. This paper presents a method for the quantitative analysis of the imidazoline and amido-amine type corrosion inhibitors in both oilfield water and crude oil samples by HPLC. The corrosion inhibitor of interest is first separated from the matrix on a small column, then derivatized to form a product which is both sensitive and selective on a fluorescence detector. Detection limits for imidazolines are around 0.2 mg/L, amides and amines are similar. The advantage of this procedure is it can be used to determine the amount of corrosion inhibitor in both oil and brine water phases as well as on solid surfaces.« less

Determination of acetylsalicylic acid in commercial tablets by SERS using silver nanoparticle-coated filter paper

NASA Astrophysics Data System (ADS)

Sallum, Loriz Francisco; Soares, Frederico Luis Felipe; Ardila, Jorge Armando; Carneiro, Renato Lajarim

2014-12-01

In this work, filter paper was used as a low cost substrate for silver nanoparticles in order to perform the detection and quantification of acetylsalicylic acid by SERS in a commercial tablet. The reaction conditions were 150 mM of ammonium hydroxide, 50 mM of silver nitrate, 500 mM of glucose, 12 min of the reaction time, 45 °C temperature, pretreatment with ammonium hydroxide and quantitative filter paper (1-2 μm). The average size of silver nanoparticles deposited on the paper substrate was 180 nm. Adsorption time of acetylsalicylic acid on the surface of the silver-coated filter paper was studied and an adsorption time of 80 min was used to build the analytical curve. It was possible to obtain a calibration curve with good precision with a coefficient of determination of 0.933. The method proposed in this work was capable to quantify acetylsalicylic acid in commercial tablets, at low concentration levels, with relative error of 2.06% compared to the HPLC. The preparation of filter paper coated with silver nanoparticles using Tollen's reagent presents several advantages such as low cost of synthesis, support and reagents; minimum amount of residuals, which are easily treated, despite the SERS spectroscopy presenting fast analysis, with low sample preparation and low amount of reactants as in HPLC analysis.

[Various methods for the determination of preservatives in food. II. Gaschromatography, high performance liquid chromatography, TAS-method (author's transl)].

PubMed

Hild, J; Gertz, C

1980-02-01

For the quantitative determination of preservatives in food, analyses were carried out by means of GLC, HPLC, and TLC according to the TAS-method. Using the alkaline extract (sample preparation see part I) the preservatives can be analysed as free acid or appropriate ester out the same GLC-column without any interference from coextractives. A fast and accurate HPLC determination can be achieved by direct injection of the alkaline extract. All preservatives were well separated and detected at a wavelength of 225 resp. 232 nm. As a quick test for the qualitative estimation the TLC (TAS) method is suggested and a suitable solvent system is proposed.

[High performance liquid chromatogram (HPLC) determination of adenosine phosphates in rat myocardium].

PubMed

Miao, Yu; Wang, Cheng-long; Yin, Hui-jun; Shi, Da-zhuo; Chen, Ke-ji

2005-04-18

To establish method for the quantitative determination of adenosine phosphates in rat myocardium by optimized high performance liquid chromatogram (HPLC). ODS HYPERSIL C(18) column and a mobile phase of 50 mmol/L tribasic potassium phosphate buffer solution (pH 6.5), with UV detector at 254 nm were used. The average recovery rates of myocardial adenosine triphosphate (ATP), adenosine diphosphate (ADP) and adenosine monophosphate (AMP) were 99%-107%, 96%-104% and 95%-119%, respectively; relative standard deviations (RSDs) of within-day and between-days were less than 1.5% and 5.1%, respectively. The method is simple, rapid and accurate, and can be used to analyse the adenosine phosphates in myocardium.

Quantitative metabolite profiling of edible onion species by NMR and HPLC-MS.

PubMed

Soininen, Tuula H; Jukarainen, Niko; Auriola, Seppo O K; Julkunen-Tiitto, Riitta; Karjalainen, Reijo; Vepsäläinen, Jouko J

2014-12-15

Allium genus is a treasure trove of valuable bioactive compounds with potentially therapeutically important properties. This work utilises HPLC-MS and a constrained total-line-shape (CTLS) approach applied to (1)H NMR spectra to quantify metabolites present in onion species to reveal important inter-species differences. Extensive differences were detected between the sugar concentrations in onion species. Yellow onion contained the highest and red onion the lowest amounts of amino acids. The main flavonol-glucosides were quercetin 3,4'-diglucoside and quercetin 4'-glucoside. In general, the levels of flavonols were, higher in yellow onions than in red onions, and garlic and leek contained a lower amount of flavonols than the other Allium species. Our results highlight how (1)H NMR together with HPLC-MS can be useful in the quantification and the identification of the most abundant metabolites, representing an efficient means to pinpoint important functional food ingredients from Allium species. Copyright © 2014 Elsevier Ltd. All rights reserved.