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Sample records for hplc

  1. HPLC Neurotransmitter Analysis.

    PubMed

    Holm, Thomas Hellesøe; Isaksen, Toke Jost; Lykke-Hartmann, Karin

    2016-01-01

    High performance liquid chromatography (HPLC) is a powerful tool to measure neurotransmitter levels in specific tissue samples and dialysates from patients and animals. In this chapter, we list the current protocols used to measure neurotransmitters in the form of biogenic amines from murine brain samples. PMID:26695044

  2. HPLC: Early and Recent Perspectives.

    ERIC Educational Resources Information Center

    Karger, Barry L.

    1997-01-01

    Provides a perspective on what it was like in the early days of high-performance liquid chromatography (HPLC) and several of the key developments. Focuses on the advances in HPLC generally, and more specifically for the biological sciences, that were necessary for the method to reach the preeminent stage of today. Contains 20 references. (JRH)

  3. ANALYSIS OF VITAMIN E BY HPLC

    Technology Transfer Automated Retrieval System (TEKTRAN)

    HPLC (High-performance liquid chromatography) is the most comon technique for identifying and measuring vitamin E concentrations. A variety of good HPLC methods are available for vitamin E analysis. Reliable and sensitive methods have been developed using reversed-phased and normal-phase HPLC column...

  4. [Determination of amanitatoxins by HPLC].

    PubMed

    Nishizawa, Chiemi; Yamaura, Yoshio

    2003-10-01

    High-performance liquid chromatographic (HPLC) assay has been developed for the simultaneous determination of alpha-amanitin, beta-amanitin and phalloidin in serum. Three toxins were extracted by reflux in a water bath at 80 degrees C for one hour and purified by Sep-Pak Plus tC18 cartridges. The HPLC assay was performed under gradient conditions using Develosil RP AQUEOUS column. The moble phase consisted with a mixture of acetonitorile containing 0.01 M ammonium acetate(pH 5.0). The column effluence was monitored at 295 nm, 302 nm and 230 nm for 35 min. Detection limit of three toxins in serum were 0.2 microgram/ml respectively. High recovery yields in the range of 81.5-88.1% for toxins were obtained by using this method. PMID:14740566

  5. HPLC for quality control of polyimides

    NASA Technical Reports Server (NTRS)

    Young, P. R.; Sykes, G. F.

    1979-01-01

    High Pressure Liquid Chromatography (HPLC) as a quality control tool for polyimide resins and prepregs are presented. A data base to help establish accept/reject criteria for these materials was developed. This work is intended to supplement, not replace, standard quality control tests normally conducted on incoming resins and prepregs. To help achieve these objectives, the HPLC separation of LARC-160 polyimide precursor resin was characterized. Room temperature resin aging effects were studied. Graphite reinforced composites made from fresh and aged resin were fabricated and tested to determine if changes observed by HPLC were significant.

  6. Determination of zinc pyrithione in shampoos by HPLC and HPLC-MS/MS.

    PubMed

    Gu, Yu-Xiang; Wang, Qing-He; Zhou, Ze-Lin; Lv, Qing; Mai, Cheng-Hua

    2014-01-01

    Methods have been developed for the determination of zinc pyrithione (ZPT) in shampoos using high-performance liquid chromatography (HPLC) and high-performance liquid chromatography-mass spectrometry/mass spectrometry (HPLC-MS/MS). Samples were washed by water first to remove surfactant and water-soluble impurities, then ultrasonic-extracted by acetonitrile-methanol for 30 min, and finally analyzed by MG C18 column (250 mm x 4.6 mm, 5 μm) or RP-18e (100 mm x 3 mm, 2 μm) plus APCI-MS/MS. Limits of detection were determined as 0.015% (HPLC) and 0.003% (HPLC-MS/MS), with a limit of quantization of 0.05% and 0.01%, respectively. The recoveries were 85.8-104% (HPLC) and 87.6-107% (HPLC-MS/MS). A good linear relationship was obtained from 3.20 μg·ml(-1) to 200 μg·ml(-1) (HPLC) and 1.00 μg·ml(-1) to 200 μg·ml(-1) (HPLC-MS/MS). The proposed methods have been successfully applied to the analysis of ZPT in many shampoos. The established two methods were rapid and reproducible with low interference. PMID:25682618

  7. Determination of CMPO using HPLC -UV

    SciTech Connect

    Gracy Elias; Gary S. Groenewold; Bruce J. Mincher; Stephen P. Mezyk

    2012-06-01

    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 system precision. CMPO-nitric acid complexes were also identified, that account for the apparent loss of CMPO in acidic environment, independent of irradiation.

  8. Determination of amphetamine by HPLC after acetylation.

    PubMed

    Veress, T

    2000-01-01

    An analytical procedure has been developed for the HPLC determination of amphetamine by off-line pre-column derivatization. The proposed procedure consists of sample preparation by acetylation of amphetamine with acetic anhydride and a subsequent reversed-phase HPLC separation on an octadecyl silica stationary phase with salt-free mobile phase (tetrahydrofuran, acetonitrile, 0.1% triethylamine in water, 15:15:70 v/v) applying UV-detection. The applicability of the elaborated procedure is demonstrated with results obtained by analysis of real samples seized in the Hungarian black market. PMID:10641931

  9. Methods and applications of HPLC-AMS

    NASA Astrophysics Data System (ADS)

    Buchholz, Bruce A.; Dueker, Stephen R.; Lin, Yumei; Clifford, Andrew J.; Vogel, John S.

    2000-10-01

    Pharmacokinetics of physiologic doses of nutrients, pesticides, and herbicides can easily be traced in humans using a 14C-labeled compound. Basic kinetics can be monitored in blood or urine by measuring the elevation in the 14C 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. Unknowns are tentatively identified by co-elution with known standards and chemical tests that reveal functional groupings. Metabolites are quantified with the 14C 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 14C per HPLC fraction are typically achieved. Baselines are maintained by limiting injected 14C activity <0.17 Bq (4.5 pCi) on the HPLC column.

  10. An Inexpensive Digital Gradient Controller for HPLC.

    ERIC Educational Resources Information Center

    Brady, James E.; Carr, Peter W.

    1983-01-01

    Use of gradient elution techniques in high performance liquid chromatography (HPLC) is often essential for direct separation of complex mixtures. Since most commercial controllers have features that are of marginal value for instructional purposes, a low-cost controller capable of illustrating essential features of gradient elution was developed.…

  11. Measurement of Menadione in urine by HPLC

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Menadione may be an important metabolite of vitamin K that is excreted in urine. A high performance liquid chromatography (HPLC) method with a C30 column, fluorescence detection and post-column zinc reduction was developed to measure menadione in urine. The mobile phase was composed of 95% methanol...

  12. HPLC analysis and purification of peptides.

    PubMed

    Mant, Colin T; Chen, Yuxin; Yan, Zhe; Popa, Traian V; Kovacs, James M; Mills, Janine B; Tripet, Brian P; Hodges, Robert S

    2007-01-01

    High-performance liquid chromatography (HPLC) has proved extremely versatile over the past 25 yr for the isolation and purification of peptides varying widely in their sources, quantity and complexity. This article covers the major modes of HPLC utilized for peptides (size-exclusion, ion-exchange, and reversed-phase), as well as demonstrating the potential of a novel mixed-mode hydrophilic interaction/cation-exchange approach developed in this laboratory. In addition to the value of these HPLC modes for peptide separations, the value of various HPLC techniques for structural characterization of peptides and proteins will be addressed, e.g., assessment of oligomerization state of peptides/proteins by size-exclusion chromatography and monitoring the hydrophilicity/hydrophobicity of amphipathic alpha-helical peptides, a vital precursor for the development of novel antimicrobial peptides. The value of capillary electrophoresis for peptide separations is also demonstrated. Preparative reversed-phase chromatography purification protocols for sample loads of up to 200 mg on analytical columns and instrumentation are introduced for both peptides and recombinant proteins. PMID:18604941

  13. Arsenic speciation in chinese seaweeds using HPLC-ICP-MS and HPLC-ES-MS.

    PubMed

    Van Hulle, Marijn; Zhang, Chao; Zhang, Xinrong; Cornelis, Rita

    2002-05-01

    Three common Chinese edible seaweeds, one brown (Laminaria japonica) and two red (Porphyra crispata and Eucheuma denticulatum), were examined for their total arsenic content. The As species were extracted with yields of 76.4, 69.8 and 25.0%, respectively. Anion-exchange and cation-exchange high-performance liquid chromatography (HPLC) in combination with inductively coupled plasma mass spectrometry (ICP-MS) were used for the separation of the different arsenic species in two of the three seaweed extracts (Laminaria and Porphyra). The main arsenic species in the algal extracts are arseno sugars, although it has been shown that the Laminaria seaweed contains significant amounts of dimethylarsinic acid (DMA). HPLC was coupled with electrospray mass spectrometry (ES-MS) for structural confirmation of the arsenic species. The mass spectrometer settings for the arseno sugars were optimised using standards. The conclusions drawn on the basis of HPLC-ICP-MS were confirmed by the HPLC-ES-MS data. The HPLC-ES-MS method is capable of determining both arseno sugars and DMA in the seaweeds. The unknown compounds seen in the HPLC-ICP-MS chromatogram of Laminaria could not be ascribed to trimethylarsenic oxide or tetramethylarsonium ion. PMID:12081041

  14. HPLC Determination of Taurine in Sports Drinks

    NASA Astrophysics Data System (ADS)

    Orth, Dale L.

    2001-06-01

    The amino acid taurine (2-aminoethanesulfonic acid) is present as a nutritional supplement in many sports drinks. An experiment, suitable for a junior-senior level instrumental analysis course, is described to measure the amount of taurine in these sports drinks. A pre-column derivatization with Sanger's reagent, 2,4-dinitrofluorobenzene, is followed by an HPLC separation utilizing a gradient elution, and detection at 360 nm.

  15. Retinoid quantification by HPLC/MS(n)

    NASA Technical Reports Server (NTRS)

    McCaffery, Peter; Evans, James; Koul, Omanand; Volpert, Amy; Reid, Kevin; Ullman, M. David

    2002-01-01

    Retinoic acid (RA) mediates most of the biological effects of vitamin A that are essential for vertebrate survival. It acts through binding to receptors that belong to the nuclear receptor transcription factor superfamily (Mangelsdorf et al. 1994). It is also a highly potent vertebrate teratogen. To determine the function and effects of endogenous and exogenous RA, it is important to have a highly specific, sensitive, accurate, and precise analytical procedure. Current analyses of RA and other retinoids are labor intensive, of poor sensitivity, have limited specificity, or require compatibility with RA reporter cell lines (Chen et al. 1995. BIOCHEM: Pharmacol. 50: 1257-1264; Creech Kraft et al. 1994. BIOCHEM: J. 301: 111-119; Lanvers et al. 1996. J. Chromatogr. B Biomed. Appl. 685: 233-240; Maden et al. 1998. DEVELOPMENT: 125: 4133-4144; Wagner et al. 1992. DEVELOPMENT: 116: 55-66). This paper describes an HPLC/mass spectrometry/mass spectrometry product ion scan (HPLC/MS(n)) procedure for the analysis of retinoids that employs atmospheric pressure chemical ionization MS. The retinoids are separated by normal-phase column chromatography with a linear hexane-isopropanol-dioxane gradient. Each retinoid is detected by a unique series of MS(n) functions set at optimal collision-induced dissociation energy (30% to 32%) for all MS(n) steps. The scan events are divided into three segments, based on HPLC elution order, to maximize the mass spectrometer duty cycle. The all-trans, 9-cis, and 13-cis RA isomers are separated, if desired, by an isocratic hexane-dioxane-isopropanol mobile phase. This paper describes an HPLC/MS(n) procedure possessing high sensitivity and specificity for retinoids.

  16. An Investigation Into HPLC Data Quality Problems

    NASA Technical Reports Server (NTRS)

    Hooker, Stanford B.; VanHeukelem, Laurie

    2011-01-01

    This report summarizes the analyses and results produced by a five-member investigative team of Government, university, and industry experts, established by NASA HQ. The team examined data quality problems associated with high performance liquid chromatography (HPLC) analyses of pigment concentrations in seawater samples produced by the San Diego State University (SDSU) Center for Hydro-Optics and Remote Sensing (CHORS). This report shows CHORS did not validate the methods used before placing them into service to analyze field samples for NASA principal investigators (PIs), even though the HPLC literature contained easily accessible method validation procedures, and the importance of implementing them, more than a decade ago. In addition, there were so many sources of significant variance in the CHORS methodologies, that the HPLC system rarely operated within performance criteria capable of producing the requisite data quality. It is the recommendation of the investigative team to a) not correct the data, b) make all the data that was temporarily sequestered available for scientific use, and c) label the affected data with an appropriate warning, e.g., "These data are not validated and should not be used as the sole basis for a scientific result, conclusion, or hypothesis--independent corroborating evidence is required."

  17. On-line identification of the bioactive compounds from Blumea gariepina by HPLC-UV-MS and HPLC-UV-NMR, combined with HPLC-micro-fractionation.

    PubMed

    Queiroz, E F; Ioset, J R; Ndjoko, K; Guntern, A; Foggin, C M; Hostettmann, K

    2005-01-01

    The dichloromethane extract of the aerial parts of Blumea gariepina (Asteraceae) was shown to be active against the phytopathogenic fungus Cladosporium cucumerinum and to inhibit acetylcholinesterase. In order rapidly to identify the active principles, the crude extract was analysed by on-flow HPLC-1H-NMR. HPLC-micro-fractionation was performed and all peaks collected were submitted to assays against C. cucumerinum and acetylcholinesterase. By this means, the biological activities could be efficiently associated with selected HPLC peaks. Complementary on-line structural data for all peaks of interest in the crude extract were obtained from HPLC-MS and from HPLC-UV with post-column addition of UV shift reagents. This chemical screening strategy with integrated bioassays permitted the on-line identification of a number of constituents and gave useful information for an efficient isolation procedure. PMID:15997849

  18. [HPLC fingerprint of liuwei dihuang soft capsule].

    PubMed

    Shi, Wei; Li, Jia-Chun; Yang, Su-De; Li, Yun; Jin, Rui-Ting; Sun, Xian-Ling; Wang, Zhen-Zhong; Bi, Yu-An; Xiao, Wei

    2014-12-01

    In order to establish HPLC fingerprint of Liuwei Dihuang soft capsule, and to provide certain reference for an quality control of it, the HPLC method was performed on an Agilent C18 (4.6 mm x 250 mm, 5 μm) column with acetonitrile-0.02% trifluoroacetic acid as mobile phase, gradient elution volume flow of 1.0 mL x min(-1), column temperature was 30 degrees C, detection wavelength: 0-60 min, 238 nm, 60-70 min, 210 nm. The software for chromatographic fingerprint was applied to analysis different batches of Liuwei Dihuang soft capsule samples. Sixteen mutual peaks were selected as the fingerprint peaks in 12 samples with loganin as the reference peak, and all of the detected peaks were separated effectively. Cluster analysis (HCA) and similarity analysis (SA) were done based on data of 12 samples clustering analysis of 12 batches of samples were divided into 2 categories. Including 7 for the first class, the rest was second, similarities calculated by SA were all above 0.92, indicating a good similarity between the reference and twelve batches of samples, also, the analysis results of HCA and SA basically the same. This method is simple with good precision, repeatability and stability, and provides the basis for Liuwei Dihuang soft capsule quality control. PMID:25911813

  19. [HPLC fingerprints in seed of Celosia argentea].

    PubMed

    Wang, Ying; Guo, Mei-Li; Wang, Xiao-Kang; Yin, Jun

    2008-01-01

    For preferable authentication and regulation of material quality of Celosia argentea, HPLC fingerprints of different habitats were studied. Analysis was carried out on a Hypersil ODS2 column (4.6 mm x 250 mm, 5 microm) with acetonitrile-0.1% glacial acetic acid as the mobile phase, and eluates were detected by an evaporative light scattering detector (ELSD). The similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine ( Version 2004 A) was applied to analyses the similarity of the fingerprint of diverse habitats. The similarity results were verified by SPSS. The chromatographic profiles of the samples from different regions were very similar. HPLC fingerprints of Semen C. argentea 12 common peaks and each peak in the fingerprint was well separated under the chromatographic condition above. The different habitats of C. argentea can be grouped to two types: the middle region and the south region. The chemical constituents of C. argentea vary with different habitats so selection of material habitat is very important for quality control of C. argentea. The fingerprint with high individuality and specificity could be applied in the identification and quality control of the material of C. argentea. PMID:18338620

  20. HPLC determination of majdine in Vinca herbacea.

    PubMed

    Gagua, Natia; Baghdikian, Beatrice; Mabrouki, Fathi; Elias, Riad; Vachnadze, Valentina; Bakuridze, Aliosha; Ollivier, Evelyne

    2011-12-01

    A reliable HPLC method coupled with DAD detection was developed and validated for determination of majdine in Vinca herbacea. The chromatographic separation was carried out on a Symmetry C18 column (250 mm x 4.6 mm, 5 microm, Waters) with an isocratic solvent system of 25 mM potassium phosphate buffer (pH = 3.0)-acetonitrile. UV detection was performed at 225 nm. Good linear behavior over the investigated concentration range was observed with the value of r2 > 0.9978. The method was reproducible with intra- and inter-day variations of less than 4.38%. The proposed method was linear, accurate, precise and specific. The validated method was successfully applied to quantify majdine in various parts of V. herbacea, which was collected during the flowering months of April and May. The results indicated that the developed HPLC method could be used for the quality control of V. herbacea and for the standardization of its extracts in majdine. PMID:22312718

  1. Measurement of Menadione in Urine by HPLC

    PubMed Central

    Rajabi, Ala Al; Peterson, James; Choi, Sang Woon; Suttie, John; Barakat, Susan; Booth, Sarah L

    2010-01-01

    Menadione is a metabolite of vitamin K that is excreted in urine. A high performance liquid chromatography (HPLC) method using a C30 column, post-column zinc reduction and fluorescence detection was developed to measure urinary menadione. The mobile phase was composed of 95% methanol with 0.55% aqueous solution and 5% DI H2O. Menaquinone-2 (MK-2) was used as an internal standard. The standard calibration curve was linear with a correlation coefficient (R2) of 0.999 for both menadione and MK-2. The lower limit of quantification (LLOQ) was 0.3 pmole menadione/mL urine. Sample preparation involved hydrolysis of menadiol conjugates and oxidizing the released menadiol to menadione. Using this method, urinary menadione was shown to increase in response to 3 years of phylloquinone supplementation. This HPLC method is a sensitive and reproducible way to detect menadione in urine. Research support: USDA ARS Cooperative Agreement 58-1950-7-707. PMID:20719580

  2. Analyses of procyanidins in foods using Diol phase HPLC

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Separation of procyanidins using silica-based HPLC suffered from poor resolution for higher oligomers and low sensitivity due to the fluorescence quenching effects of methylene chloride in the mobile phase. Optimization of a published Diol-phase HPLC method resulted in near baseline separation for p...

  3. Optimizing Chromatographic Separation: An Experiment Using an HPLC Simulator

    ERIC Educational Resources Information Center

    Shalliker, R. A.; Kayillo, S.; Dennis, G. R.

    2008-01-01

    Optimization of a chromatographic separation within the time constraints of a laboratory session is practically impossible. However, by employing a HPLC simulator, experiments can be designed that allow students to develop an appreciation of the complexities involved in optimization procedures. In the present exercise, a HPLC simulator from "JCE…

  4. HPLC and HPLC/MS analysis of red ink on counterfeit 100-yuan notes.

    PubMed

    Xu, Ying-jian; Zhou, Xin-xin; Shi, Xiao-fan

    2016-02-01

    Counterfeiting is a significant problem for most major currencies and has high social and economic costs. Chemical and physical identifiers that are unique to counterfeit currency are critical to forensic analysis. The 100-yuan Chinese note is mostly red. Here, we analyzed the red ink used in 100-yuan Chinese notes and developed a method to extract and analyze these dyes via high performance liquid chromatography (HPLC) and HPLC/mass spectrometry (MS). We used this approach to analyze the chemical structures of the adulterated colorants from 46 counterfeit 100-yuan notes seized from different locations. The results showed that a variety of inks were found among the seized counterfeit notes from different sources. The chromatographic data signature could be used to clearly discriminate authentic from counterfeit notes, but could also potentially be used to trace the notes to the counterfeiter. To the best of our knowledge, this is the first report to use HPLC/MS to profile red dyes in Chinese currency with important implications for the forensics and law enforcement communities. PMID:26750988

  5. HPLC and HPLC-MS as tools to monitor the quality of vegetable oils, nutraceuticals, and functional foods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    HPLC and HPLC-MS have become valuable tools to analyze the “functional lipids” in vegetable oils, nutraceuticals, functional foods, and conventional foods. These functional lipids include phytosterols, tocopherols, tocotrienols, and carotenoids. These analytical methods have provided a means to id...

  6. Efficient and economic HPLC performance qualification.

    PubMed

    Kaminski, Lukas; Degenhardt, Matthias; Ermer, Joachim; Feussner, Claus; Höwer-Fritzen, Heidemarie; Link, Peter; Renger, Bernd; Tegtmeier, Martin; Wätzig, Hermann

    2010-02-01

    Analytical instrument qualification (AIQ) is a prerequisite for any analytical method validation and thus must be considered as a vital basis of analytical data integrity and quality in pharmaceutical analysis. There is a well-established system of qualification phases-Design Qualification, Installation Qualification (IQ), Operational Qualification (OQ) and Performance Qualification (PQ). As HPLC systems are "off the shelf" equipment, Design Qualification may be disregarded here. IQ establishes that the instrument is received as designed and that it is properly installed. OQ is carried out modularly with the intention to ensure that the specific modules of the system and the whole system are operating according to the defined specifications. PQ as the last step of the initial qualification is supposed to ensure continued satisfactory performance of an instrument under actual running conditions over the anticipated working range during daily use. However, PQ is not a one time exercise, but is currently repeated regularly independently from routine use of the analytical system using standard reference test condition. But this approach, which is time consuming and expensive only provides a snapshot of system performance. As HPLC procedures generally require a system suitability test (SST) prior and/or after test, it might be far more reasonable and robust to use these SST data for a continuous PQ. The work presented here demonstrates that, under certain circumstances, satisfactory instrument performance assessment can be derived from system suitability tests and performance data from daily use as well. A generally accepted qualification list, consisting of only twelve critical parameters, was compiled in a first step. Some parameters such as injector or thermostatting accuracy were considered redundant while others were successfully incorporated in the proposed holistic approach. System suitability test data as well as OQ/PQ data were provided from different sources

  7. 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. PMID:21497475

  8. Fingerprint of Hedyotis diffusa Willd. by HPLC-MS.

    PubMed

    Yang, Ting; Yang, Yi-Hua; Yang, Ju-Yun; Chen, Ben-Mei; Duan, Ju-Ping; Yu, Shu-Yi; Ouyang, Hong-Tao; Cheng, Jun-Ping; Chen, Yu-Xiang

    2008-01-01

    A HPLC-MS fingerprint method has been developed based on the consistent chromatographic features of the major chemical constituents among 10 batches of Hedyotis diffusa Willd. Chromatographic separation was conducted on a Hypersil-Keystone Hypurity C(18) column using methanol:water:acetic acid as the mobile phase. Major compounds, including oleanolic acid, ursolic acid and ferulic acid, were analysed by HPLC-MS. Their analysis was ascertained by comparison with data derived from the standard compounds. The HPLC-MS fingerprint was successfully applied to analyse and differentiate samples from different geographical origins, or processing methods. H. diffusa was well distinguished from Hedyotis chrysotricha by HPLC-MS. Therefore the establishment of fingerprint of H. diffusa is critical in assessing and controlling its overall quality. PMID:18446772

  9. Analysis of munitions constituents in IMX formulations by HPLC and HPLC-MS.

    PubMed

    Russell, A L; Seiter, J M; Coleman, J G; Winstead, B; Bednar, A J

    2014-10-01

    The use of Insensitive Munitions eXplosives (IMX) is increasing as the Army seeks to replace certain conventional munitions constituents, such as 2,4,6-trinitrotolene (TNT), for improved safety. The IMX formulations are more stable and therefore less prone to accidental detonation while designed to match the performance of legacy materials. Two formulations, IMX 101 and 104 are being investigated as a replacement for TNT in artillery rounds and composition B Army mortars, respectively. The chemical formulations of IMX-101 and 104 are comprised of four constituents;2,4-dinitroanisole (DNAN), 3-nitro-1,2,4-triazol-5-one (NTO), 1-nitroguanidine (NQ), and Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) which are mixed in various ratios to achieve the desired performance. The current work details the analysis of the IMX constituents by single column HPLC-UV-ESI-MS. Detection limits determined are in agreement with similar HPLC analysis of compounds, ranging from 7 to 9μg/L. Gradient mobile phases are used to allow separation of the 4 target compounds in more complex mixture of other concomitant compounds. Mass spectra are used to confirm analyte identity with chromatographic retention time. PMID:25059196

  10. Identification of monofloral honeys using HPLC-ECD and chemometrics.

    PubMed

    Zhao, Jing; Du, Xiaojing; Cheng, Ni; Chen, Lanzhen; Xue, Xiaofeng; Zhao, Jing; Wu, Liming; Cao, Wei

    2016-03-01

    A total of 77 jujube, longan and chaste honey samples were collected from 18 different areas of China. Thirteen types of phenolic acids in the honey samples were analysed using high-performance liquid chromatography with electrochemical detection (HPLC-ECD). Moreover, HPLC-ECD fingerprints of the monofloral honey samples were established. From the analysis of the HPLC-ECD fingerprints, common chromatography peak information was obtained, and principal component analysis and discriminant analysis were performed using selected common chromatography peak areas as variables. By comparing with phenolic acids as variables, using a chemometric analysis which is based on the use of common chromatography peaks as variables, 36 honey samples and 41 test samples could be correctly identified according to their floral origin. PMID:26471540

  11. Analysis of hydrogen peroxide field samples by HPLC/FD and HPLC/ED in DC mode.

    PubMed

    Tarvin, Megan; McCord, Bruce; Mount, Kelly; Miller, Mark L

    2011-06-15

    The goal of this paper is to describe applications of two recently developed HPLC methods for the analysis and confirmation of the presence of hydrogen peroxide residues in field studies. The procedure utilizes two different HPLC systems, one with post-column derivatization followed by fluorescence detection (HPLC/FD), and the other with electrochemical detection (HPLC/ED). The two systems were utilized to detect hydrogen peroxide in a variety of typical forensic samples including pre- and post-blast samples, as well as a series of environmental control samples. Peroxide-based organic explosives were also examined due to their propensity to produce peroxide residues following detonation. Because samples collected from post-blast scenes are frequently shipped or stored prior to analysis, the effects of storage time, temperature and type of substrate material on the recovery of hydrogen peroxide residues were also investigated. The combined results of the study demonstrate the capability of two HPLC approaches with selective detection in the analysis and investigation of suspected incidents involving peroxide based explosives. PMID:21324615

  12. In vitro duodenal lipolysis of lipid-based drug delivery systems studied by HPLC-UV and HPLC-MS.

    PubMed

    Wulff-Pérez, Miguel; Barrajón-Catalán, Enrique; Micol, Vicente; Martín-Rodríguez, Antonio; de Vicente, Juan; Gálvez-Ruíz, María J

    2014-04-25

    Oral drug delivery systems based on lipids are biodegraded in a process called lipolysis to release free fatty acids and monoglycerides. The rate of this lipolysis is usually measured by pH titration. Nevertheless, this technique has some limitations, such as not providing any information about the actual composition of the lipolytic products. In this study, we propose a method to analyze these products during and after lipolysis using HPLC. For the first time, HPLC-UV and HPLC-MS have been used to investigate in vitro duodenal lipolysis of long- and medium-chain triglycerides nanoemulsions. These results have been compared with pH titration, revealing the complementarity of both techniques. The main free fatty acids and monoglycerides produced were effectively identified and quantified as they were formed and after the lipolysis experiment and subsequent ultracentrifugation. The release of fatty acids during lipolysis was qualitatively similar between the compared techniques, although a partial precipitation of medium chain fatty acids could be revealed with HPLC-MS. In addition, the release of two hydrophobic compounds with health benefits, oleoylethanolamide and carnosic acid, was investigated. In conclusion, this study may serve as a starting point for subsequent investigations regarding biodegradation and absorption of lipid-based drug delivery systems using HPLC. PMID:24560636

  13. Identification and quantification of coumarins in Peucedanum ostruthium (L.) Koch by HPLC-DAD and HPLC-DAD-MS.

    PubMed

    Vogl, Sylvia; Zehl, Martin; Picker, Paolo; Urban, Ernst; Wawrosch, Christoph; Reznicek, Gottfried; Saukel, Johannes; Kopp, Brigitte

    2011-05-11

    The rhizomes of Peucedanum ostruthium (L.) Koch (masterwort) are traditionally used in the alpine region as ingredient of liqueurs and bitters, and as a herbal drug. A sensitive and specific high-performance liquid chromatography-diode-array detection-mass spectrometry (HPLC-DAD-MS) method has been developed for the simultaneous identification and quantification of its main coumarins, oxypeucedanin hydrate, oxypeucedanin, ostruthol, imperatorin, osthole, isoimperatorin, and ostruthin. Fast HPLC separation could be achieved on an Acclaim C18 column (150 mm × 2.1 mm i.d., 3 μm) using a mobile phase gradient of acetonitrile-water modified with 0.01% acetic acid. The quantification by HPLC-DAD was performed with imperatorin as external standard and validated to demonstrate selectivity, linearity, precision, and accuracy. The content of the main coumarins was quantitated in various batches of commercial and field-collected rhizomes of Peucedanum ostruthium, as well as in beverages prepared thereof. PMID:21425828

  14. Differentiation of tannin-containing herbal drugs by HPLC fingerprints.

    PubMed

    He, Yu; Wu, Qiaofeng; Hansen, S H; Cornett, C; Møller, C; Lai, Pingfan

    2013-03-01

    A new HPLC system coupled with multiple detectors - Diode array detector (DAD), fluorescence detector (FLD), electrochemical amperometric detector (ADC) and mass spectrometry detector (MSD) was developed for the characterization and differentiation of tannin-containing herbal drugs included in The European Pharmacopoeia. The HPLC separation system consisted of an Agilent ZORBAX Eclipse XDB C18 column and a gradient water and methanol as the mobile phase which was kept at a flow rate of 0.3 mL x min(-1). Four kinds of detectors were connected by a micro-splitter valve and simultaneously recorded the response of each analytical sample. Thirty-one samples from eight kinds of tannin-containing drugs were measured using this HPLC system and their signals from all detectors were comprehensively processed via principal component analysis (PCA). The statistic result demonstrates that thirty-one batches from different herbal drugs can be reasonably identified and systematically classified by their chemical fingerprints. The proposed multi-detector HPLC method aided by chemometrics not only offers a new pattern for the study of tannin-containing herbs, but also provides a useful foundation for quality control of herbal medicines. PMID:23556331

  15. HPLC-Chip/MS technology in proteomic profiling.

    PubMed

    Vollmer, Martin; van de Goor, Tom

    2009-01-01

    HPLC-chip/MS is a novel nanoflow analytical technology conducted on a microfabricated chip that allows for highly efficient HPLC separation and superior sensitive MS detection of complex proteomic mixtures. This is possible through on-chip preconcentration and separation with fluidic connection made automatically in a leak-tight fashion. Minimum precolumn and postcolumn peak dispersion and uncompromised ease of use result in compounds eluting in bands of only a few nanoliters. The chip is fabricated out of bio-inert polyimide-containing channels and integrated chip structures, such as an electrospray emitter, columns, and frits manufactured by laser ablation technology. Meanwhile, a variety of HPLC-chips differing in design and stationary phase are commercially available, which provide a comprehensive solution for applications in proteomics, glycomics, biomarker, and pharmaceutical discovery. The HPLC-chip can also be easily integrated into a multidimensional separation workflow where different orthogonal separation techniques are combined to solve a highly complex separation problems. In this chapter, we describe in detail the methodological chip usage and functionality and its application in the elucidation of the protein profile of human nucleoli. PMID:19488689

  16. HPLC characterization of betalains from plants in the amaranthaceae.

    PubMed

    Cai, Yizhong; Sun, Mei; Corke, Harold

    2005-10-01

    HPLC characterization of reversed-phase (RP) high-performance liquid chromatography (HPLC) has been widely used in separation and identification of plant pigments. An effective RP-HPLC-based method is established to systematically isolate, identify, and quantitate the betalain pigments in the plants of 37 species of eight genera in the Amaranthaceae. A total of 16 betacyanins and three betaxanthins are characterized mainly using the RP-HPLC method and also with the aid of mass spectroscopy. The identified betacyanins include eight amaranthine-types, six gomphrenin-types, and two betanin-types. They are also divided into six simple (nonacylated) betacyanins and 10 acylated betacyanins. Acylated betacyanins are identified as betanidin 5-O-beta-glucuronosylglucoside or betanidin 6-O-beta-glucoside acylated with ferulic, p-coumaric, or 3-hydroxy-3-methylglutaric acids. Three betaxanthins were separated from Celosia species in the Amaranthaceae and identified to be immonium conjugates of betalamic acid with dopamine, 3-methoxytyramine, and (S)-tryptophan; the latter two are found to be new betaxanthins from plants. PMID:16212790

  17. HPLC and TLC characterisation of ecdysteroid alkyl ethers.

    PubMed

    Lapenna, Silvia; Dinan, Laurence

    2009-10-01

    Semi-synthetic ecdysteroid alkyl ethers have increased potential over natural ecdysteroids as actuators of ligand-inducible gene-expression systems based on the ecdysteroid receptor for in vivo applications. However, a scalable synthesis of these compounds has yet to be developed. We report a set of reversed-phase (RP; C(18) and C(6)) and normal-phase (NP; diol) HPLC systems which can be used to analyse and separate ecdysteroid ethers with single or multiple O-methyl substitutions at the 2alpha-, 3beta-, 14alpha-, 22- and 25-positions. The elution order of methyl ether analogues of the prototypical ecdysteroid 20-hydroxyecdysone (20E) was 3-methyl<2-methyl<14-methyl<25-methyl<22-methyl with both C(18)- and C(6)-RP-HPLC, when eluted with methanol/water mixtures. Further, the elution order of 20E 22-O-alkyl ethers was methylHPLC. Moreover, the ecdysteroid alkyl ethers can also be adequately resolved by NP-HPLC and silica HPTLC. On the latter, detection of ecdysteroid O-alkyl ethers with the p-anisaldehyde/sulphuric acid reagent distinguishes 22-O-alkyl ethers from non-22-O-alkyl ether analogues by the colour of the resulting spot. PMID:19648067

  18. Correlation of Two Anthocyanin Quantification Methods: HPLC and Spectrophotometric Methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pH differential method and HPLC are methods that are commonly used by researchers and the food industry for quantifying anthocyanins in a sample. This study was conducted to establish a relationship between the two analytical methods. Seven juice samples containing an array of different individu...

  19. Lipid analysis via HPLC with a charged aerosol detector

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most lipid extracts are a mixture of saturated and unsaturated molecules. Therefore, the most successful HPLC detectors for the quantitative analysis of lipids have involved the use of “universal” or “mass” detectors such as flame ionization detectors (FID) and evaporative light scattering detectors...

  20. Determination of Biogenic Amines with HPLC-APCI-MS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Determination of biogenic amines in fish samples can be used as a quality attribute and are commonly performed using a derivatization step followed by high pressure liquid chromatography (HPLC) and UV detection. Over estimation and misidentification of biogenic amines can occur when interfering comp...

  1. Methods and applications of HPLC-AMS (WBio 5)

    SciTech Connect

    Bucholz, B A; Clifford, A J; Duecker, S R; Lin, Y; Vogel, J S

    1999-09-29

    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. 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.

  2. Separation of kafirins on surface porous RP-HPLC columns

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Surface porous HPLC columns were investigated for the separation of kafarins, storage proteins of grain sorghum. Kafirins were successfully separated using C3, C8 and C18 surface porous stationary phases in less than 17 min. Separations using a monolithic C18 stationary phase were also developed ...

  3. HPLC ANALYSIS OF VINCLOZOLIN AND ITS METABOLITES IN SERUM

    EPA Science Inventory


    HPLC ANALYSIS OF VINCLOZOLIN AND ITS METABOLITES IN SERUM. A Sierra-Santoyo1,2, H A Barton1 and M F Hughes1. 1US EPA, ORD, NHEERL, ETD, RTP, NC; 2Toxicology Section, CINVESTAV-IPN, Mexico City, Mexico.

    The fungicide vinclozolin (V) is used predominantly for treatment...

  4. Analysis of benzalkonium chloride and its homologs: HPLC versus HPCE.

    PubMed

    Prince, S J; McLaury, H J; Allen, L V; McLaury, P

    1999-05-01

    Benzalkonium chloride (BAK) is a mixture of alkylbenzyldimethylammonium chloride homologs with n-C,2H25, n-C,4H29, and n-C16H33 comprising a major portion of the alkyl groups present. An analytical method for BAK must differentiate and quantitate the homologs in the BAK mixture. Reversed-phase high performance liquid chromatography (HPLC) separates compounds based on their affinity for a nonpolar column, which is a direct correlation to the compounds' polarity. High performance capillary electrophoresis (HPCE), however, separates compounds in an electric field according to their charge and size. The BAK homologs are suitable for separation by either of these methods because their polarity and sizes differ significantly. The HPLC method employed a mobile phase of 60% acetonitrile and 40% 0.1 M sodium acetate buffer pH 5 pumped at 1.0 ml min(-1), a 4.6 x 250 mm cyano column with 5 microm packing, and UV detection at 254 nm. The HPCE method utilized a run buffer of 30% acetonitrile and 70% 0.05 M sodium phosphate pH 3.06, a 50 microm x 20 cm open silica capillary, 7.5 kV electric field and UV detection at 214 nm. Both HPLC and HPCE demonstrated good linearity in the range of 0.025 to 0.8 mg ml(-1) with r2 values of approximately 0.99. The HPLC method produced good separation of the homolog peaks with a total analysis time of 25 min. HPCE run time was less than 5 min and demonstrated good separation of the three homologs. The HPLC method, however, was superior to HPCE in the areas of sensitivity and precision. The HPLC has been extensively used in the routine quantitation and qualitation of benzalkonium chloride concentrations in various products; however, long analysis times make this method inefficient. The HPCE method produced comparable results to the HPLC method but with much shorter analysis times. An HPCE analysis method, as presented here, may prove to be a much more useful and efficient method for the analysis of benzalkonium chloride and its homologs. PMID

  5. Extraction, Separation, and Identification of Phenolic Compounds in Virgin Olive Oil by HPLC-DAD and HPLC-MS.

    PubMed

    Tasioula-Margari, Maria; Tsabolatidou, Eleftheria

    2015-01-01

    The aim of this study was to evaluate the recovery of individual phenolic compounds extracted from virgin olive oil (VOO), from different Greek olive varieties. Sufficient recoveries (90%) of all individual phenolic compounds were obtained using methanol as an extraction solvent, acetonitrile for residue solubilization, and two washing steps with hexane. Moreover, in order to elucidate structural characteristics of phenolic compounds in VOO, high performance liquid chromatography with a diode array detector (HPLC-DAD) at 280 and 340 nm and HPLC coupled to electrospray ionization mass spectrometry (HPLC-ESI-MS) in the negative-ion mode were performed. The most abundant phenolic compounds were oleuropein derivatives with m/z 319 and 377 and ligstroside derivatives with m/z 303, 361. Lignans, such as 1-acetoxypinoresinol and pinoresinol were also present in substantial quantities in the phenolic fraction. However, pinoresinol was co-eluted with dialdehydic form of ligstroside aglycone (DAFLA) and it was not possible to be quantified separately. The phenolic extracts, obtained from different VOO samples, yielded similar HPLC profiles. Differences, however, were observed in the last part of the chromatogram, corresponding to isomers of the aldehydic form of ligstroside aglycone. Oxidized phenolic products, originating from secoiridoids, were also detected. PMID:26783843

  6. Selenium speciation analysis of Misgurnus anguillicaudatus selenoprotein by HPLC-ICP-MS and HPLC-ESI-MS/MS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  7. Extraction, Separation, and Identification of Phenolic Compounds in Virgin Olive Oil by HPLC-DAD and HPLC-MS

    PubMed Central

    Tasioula-Margari, Maria; Tsabolatidou, Eleftheria

    2015-01-01

    The aim of this study was to evaluate the recovery of individual phenolic compounds extracted from virgin olive oil (VOO), from different Greek olive varieties. Sufficient recoveries (90%) of all individual phenolic compounds were obtained using methanol as an extraction solvent, acetonitrile for residue solubilization, and two washing steps with hexane. Moreover, in order to elucidate structural characteristics of phenolic compounds in VOO, high performance liquid chromatography with a diode array detector (HPLC-DAD) at 280 and 340 nm and HPLC coupled to electrospray ionization mass spectrometry (HPLC-ESI-MS) in the negative-ion mode were performed. The most abundant phenolic compounds were oleuropein derivatives with m/z 319 and 377 and ligstroside derivatives with m/z 303, 361. Lignans, such as 1-acetoxypinoresinol and pinoresinol were also present in substantial quantities in the phenolic fraction. However, pinoresinol was co-eluted with dialdehydic form of ligstroside aglycone (DAFLA) and it was not possible to be quantified separately. The phenolic extracts, obtained from different VOO samples, yielded similar HPLC profiles. Differences, however, were observed in the last part of the chromatogram, corresponding to isomers of the aldehydic form of ligstroside aglycone. Oxidized phenolic products, originating from secoiridoids, were also detected. PMID:26783843

  8. Analysis of Biomass Sugars Using a Novel HPLC Method

    SciTech Connect

    Agblevor, F. A.; Hames, B. R.; Schell, D.; Chum, H. L.

    2007-01-01

    The precise quantitative analysis of biomass sugars is a very important step in the conversion of biomass feedstocks to fuels and chemicals. However, the most accurate method of biomass sugar analysis is based on the gas chromatography analysis of derivatized sugars either as alditol acetates or trimethylsilanes. The derivatization method is time consuming but the alternative high-performance liquid chromatography (HPLC) method cannot resolve most sugars found in biomass hydrolysates. We have demonstrated for the first time that by careful manipulation of the HPLC mobile phase, biomass monomeric sugars (arabinose, xylose, fructose, glucose, mannose, and galactose) can be analyzed quantitatively and there is excellent baseline resolution of all the sugars. This method was demonstrated for standard sugars, pretreated corn stover liquid and solid fractions. Our method can also be used to analyze dimeric sugars (cellobiose and sucrose).

  9. Quantification of astaxanthin in shrimp waste hydrolysate by HPLC.

    PubMed

    López-Cervantes, J; Sánchez-Machado, D I; Gutiérrez-Coronado, M A; Ríos-Vázquez, N J

    2006-10-01

    In the present study, a simple and rapid reversed-phase HPLC method for the determination of astaxanthin in shrimp waste hydrolysate has been developed and validated. The analytical procedure involves the direct extraction of astaxanthin from the lipid fraction with methanol. The analytical column, SS Exil ODS, was operated at 25C. The mobile phase consisted of a mixture of water:methanol:dichloromethane:acetonitrile (4.5:28:22:45.5 v/v/v/v) at a flow rate of 1.0 mL/min. Detection and identification were performed using a photodiode array detector (lambda(detection) = 476 nm). The proposed HPLC method showed adequate linearity, repeatability and accuracy. PMID:16802328

  10. Gradient Scouting in Reversed-Phase HPLC Revisited

    ERIC Educational Resources Information Center

    Alcazar, A.; Jurado, J. M.; Gonzalez, A. G.

    2011-01-01

    Gradient scouting is the best way to decide the most suitable elution mode in reversed-phase high-performance liquid chromatography (RP-HPLC). A simple rule for this decision involves the evaluation of the ratio [delta]t/t[subscript G] (where [delta]t is the difference in the retention time between the last and the first peak and t[subscript G] is…

  11. HPLC quantification of zolpidem and prothipendyl in a voluntary intoxication.

    PubMed

    Debailleul, G; Khalil, F A; Lheureux, P

    1991-01-01

    Zolpidem, a recently developed sleep inducer, and prothipendyl, a neuroleptic azaphenothiazine, were involved in a voluntary intoxication along with ethanol. After administration of flumazenil, a specific benzodiazepines antagonist, respiratory depression was corrected. HPLC with UV detection methods after selective extraction were developed to measure simultaneously prothipendyl and zolpidem without flumazenil interaction. These methods could be applied in drug monitoring and in emergency toxicology. PMID:1675298

  12. The Use of HPLC for the Characterization of Phytoplankton Pigments.

    PubMed

    Garrido, José L; Roy, Suzanne

    2015-01-01

    HPLC is still the technique of choice for the analysis and characterization of phytoplankton pigments. In this chapter we describe procedures for sample preparation and pigment extraction, and the use of octyl silica columns and pyridine-containing mobile phases to separate chlorophylls and carotenoids. The identification of pigments on the basis of their retention times and visible spectra, the preparation of pigment standards, and the quantitative analysis by either external or internal standard procedures are also described. PMID:26108510

  13. [Validation of a HPLC method for ochratoxin A determination].

    PubMed

    Bulea, Delia; Spac, A F; Dorneanu, V

    2011-01-01

    Ochratoxin A is a mycotoxin produced by various species of Aspergillus and Penicillium. Ochratoxin A has been detected in cereals and cereal products, coffee beans, beer, wine, spices, pig's kidney and cow's milk. For ochratoxin A, a HPLC method was developed and validated. Ochratoxin A was determined by RP-HPLC, using a liquid chromatograph type HP 1090 Series II, equiped with a fluorescence detector. The analysis was performed with a Phenomenex column, type Luna C18(2) 100A (150 x 4.6 mm; 5 microm) with a mobile phase consisting of a mixture of acetonitrile/water/acid acetic (99/99/2), a flow of 0.7 mL/min. For detection, the wavelenght of excitation was 228 nm and wavelenght of emision was 423 nm. The calibration graph was linear in 6.25-50 ng/mL concentration range (r2 = 0,9991). The detection limits was 1.6 ng/mL and the quantification limit was 4.9 ng/mL. The method precision (RSD = 2.4975%) and the accuracy (recovery was 100.1%) were studied. The HPLC method was applyed for ochratoxin A from food samples with good results. PMID:21870763

  14. TLC and HPLC methods to follow the synthesis of vinorelbine.

    PubMed

    Chunfang, Zhao; Yin, Xiong; Longjiang, Yu; Shuo, Li; Zeqiang, Wu

    2010-09-01

    The thin-layer chromatography (TLC) combined with high-performance liquid chromatography (HPLC) has been proved to be a quick and valid method to detect the intermediates and the end-product created during the chemosynthesis process of vinorelbine (VB). This paper gives a detailed investigation on the results of two determination methods when the condition of the detection changed. It shows that when TLC developer is consisted of petroleum ether, chloroform, acetone, and diethyl amine (23.5:12:2:2.5, v/v/v/v), vinblastine sulfate (VBS), anhydrovinblastine (AHVB), and VB can be separated specifically. When the mobile phase of HPLC is a mixture of methyl alcohol, acetonitrile, diethyl amine, and high purity water (420:252:3:225; v/v/v/v), adjusted with orthophosphoric acid to pH 6.5, the intermediates and the resultants of the chemosynthesis of VB can be determined effectively. It can also be used to fix quantify of the resultants. The calibration curve for VB shows good linearity in the two mass concentration ranges of 0.0100-0.0500 mg/mL (r = 0.9956) and 0.00600-0.0100 mg/mL (r = 0.9978), respectively. The limit of detection of HPLC for VB is 0.200 microg/mL. PMID:20819300

  15. Quality evaluation of Perillae Folium by HPLC/PDA.

    PubMed

    Zhao, Bing Tian; Lee, Kang Ro; Lee, Je Hyun; Min, Byung Sun; Son, Jong Keun; Woo, Mi Hee

    2015-08-01

    To establish a standard of quality control for Perillae Folium (Lamiaceae Family), four standard compounds including rosmarinic acid, elemicin, perillaldehyde, and dillapiole were evaluated by high-performance liquid chromatography (HPLC)/photodiode array (PDA). The four standards were analyzed with a Phenomenex Kinetex C18 (250 × 4.6 mm, 5 μm) column by gradient elution using 0.1 % formic acid in water and methanol as the mobile phase. The standards were quantified by HPLC/PDA from Perillae Folium, which included the leaf and twig of Perilla frutescens L. Britton var. acuta (Thunb.) Kudo or Perilla frutescens Britton var. crispa Decne. The method was successfully used in the analysis of Perillae Folium, and the linearity, recovery, precision, accuracy, stability, and robustness were satisfactory according to the validation results. In Perillae Folium samples, the average contents (wt%) of rosmarinic acid, elemicin, perillaldehyde, and dillapiole were 0.540, 0.059, 0.050, and 0.056 %, respectively. The results indicate that the established HPLC/PDA method is suitable for the quantitation and quality evaluation of Perillae Folium. PMID:25716430

  16. Surface confined ionic liquid as a stationary phase for HPLC

    SciTech Connect

    Wang, Qian; Baker, Gary A; Baker, Sheila N; Colon, Luis

    2006-01-01

    Trimethoxysilane ionosilane derivatives of room temperature ionic liquids based on alkylimidazolium bromides were synthesized for attachment to silica support material. The derivatives 1-methyl-3-(trimethoxysilylpropyl)imidazolium bromide and 1-butyl-3-(trimethoxysilylpropyl)imidazolium bromide were used to modify the surface of 3 {micro}m diameter silica particles to act as the stationary phase for HPLC. The modified particles were characterized by thermogravimetric analysis (TGA) and {sup 13}C and {sup 29}Si NMR spectroscopies. The surface modification procedure rendered particles with a surface coverage of 0.84 {micro}mol m{sup -2} for the alkylimidazolium bromide. The ionic liquid moiety was predominantly attached to the silica surface through two siloxane bonds of the ionosilane derivative (63%). Columns packed with the modified silica material were tested under HPLC conditions. Preliminary evaluation of the stationary phase for HPLC was performed using aromatic carboxylic acids as model compounds. The separation mechanism appears to involve multiple interactions including ion exchange, hydrophobic interaction, and other electrostatic interactions.

  17. Qualitative and quantitative analysis of chemical constituents of Centipeda minima by HPLC-QTOF-MS & HPLC-DAD.

    PubMed

    Chan, Chi-On; Jin, Deng-Ping; Dong, Nai-Ping; Chen, Si-Bao; Mok, Daniel Kam Wah

    2016-06-01

    A high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-QTOF-MS) method in both positive and negative ion modes was established to investigate the major constituents in the ethanolic extract of Centipeda minima (EBSC). Twelve common components including flavones and their glycosides, phenolic and polyphenolic acids, and sesquiterpene lactone were identified in ten batches of samples based on comparison with the retention time and accurate mass of external standards (mass accuracy within 3ppm) or the fragmentation patterns of tandem MS. Meanwhile, a simple, accurate and reliable HPLC-DAD method was also developed to determine the content of 10 chemical markers simultaneously. Results obtained from method validations including linearity, accuracy and precision showed that this new method is reliable and robust. Isochlorogenic acid A and brevilin A were found to be the most abundant in the ethanol extract of EBSC and could be served as markers for quality control of EBSC. PMID:27131150

  18. Determination of Sinomenine in Cubosome Nanoparticles by HPLC Technique

    PubMed Central

    Zhou, Yanfang; Guo, Chunlian; Chen, Hongying; Zhang, Yudai; Peng, Xinsheng; Zhu, Ping

    2015-01-01

    We applied HPLC technique to quantitatively analyze sinomenine in cubosome nanoparticles. The chromatographic method was performed by 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; the detection wavelength was at 265 nm. Sinomenine can be successfully separated with good linearity (the regression equation is A = 10835C + 1058; R2 = 1.0) and perfect recovery (102.2%). The chromatograph technique was proper for quality control of sinomenine in cubosome nanoparticles. PMID:25734024

  19. Urine Pyrimidine Metabolite Determination by HPLC Tandem Mass Spectrometry.

    PubMed

    Sun, Qin

    2016-01-01

    Pyrimidine diseases result from deficiencies in pyrimidine de novo synthesis, degradation, and salvage pathways. Enzymatic deficiencies in pyrimidine catabolism lead to mitochondrial neurogastrointestinal encephalopathy (MNGIE), pyrimidinuria, dihydropyrimidinuria, ureidopropionic aciduria, and other disorders. While MNGIE presents with gastrointestinal dysmotility, cachexia, and leukoencephalopathy, pyrimidinuria and dihydropyrimidinuria may show symptoms of epilepsy, autism, mental retardation, and dysmorphic features. The application of HPLC-MS/MS facilitates rapid screening of pyrimidine metabolites. Here we describe an LCMS method for determination of uracil, thymine, thymidine, dihydrouracil, and dihydrothymine that are diagnostic biomarkers of MNGIE, pyrimidinuria, and dihydropyrimidinuria. PMID:26602135

  20. Coral Pigments: Quantification Using HPLC and Detection by Remote Sensing

    NASA Technical Reports Server (NTRS)

    Cottone, Mary C.

    1995-01-01

    Widespread coral bleaching (loss of pigments of symbiotic dinoflagellates), and the corresponding decline in coral reef health worldwide, mandates the monitoring of coral pigmentation. Samples of the corals Porites compressa and P. lobata were collected from a healthy reef at Puako, Hawaii, and chlorophyll (chl) a, peridinin, and Beta-carotene (Beta-car) were quantified using reverse-phase high performance liquid chromatography (HPLC). Detailed procedures are presented for the extraction of the coral pigments in 90% acetone, and the separation, identification, and quantification of the major zooxanthellar pigments using spectrophotometry and a modification of the HPLC system described by Mantoura and Llewellyn (1983). Beta-apo-8-carotenal was found to be inadequate as in internal standard, due to coelution with chl b and/or chl a allomer in the sample extracts. Improvements are suggested, which may result in better resolution of the major pigments and greater accuracy in quantification. Average concentrations of peridinin, chl a, and Beta-car in corals on the reef were 5.01, 8.59, and 0.29, micro-grams/cm(exp 2), respectively. Average concentrations of peridinin and Beta-car did not differ significantly between the two coral species sampled; however, the mean chl a concentration in P. compressa specimens (7.81 ,micro-grams/cm(exp 2) was significantly lower than that in P. lobata specimens (9.96 11g/cm2). Chl a concentrations determined spectrophotometrically were significantly higher than those generated through HPLC, suggesting that spectrophotometry overestimates chl a concentrations. The average ratio of chl a-to-peridinin concentrations was 1.90, with a large (53%) coefficient of variation and a significant difference between the two species sampled. Additional data are needed before conclusions can be drawn regarding average pigment concentrations in healthy corals and the consistency of the chl a/peridinin ratio. The HPLC pigment concentration values

  1. [Analysis of HPLC and NIRS fingerprints of Chrysanthemum indicum of different processing methods].

    PubMed

    Hu, Xiao-li; Bai, Yan; Lei, Jing-wei; Zhang, Di-wen; Hao, Min

    2015-10-01

    This paper studied the HPLC and NIRS fingerprints of Chrysanthemum with different processing methods, including directly drying, drying after steamed, and drying after fried. The method of discriminant analysis of TQ software was used to analysis the NIRS fingerprint of Chrysanthemum with three different processing methods, and the results were consistent with HPLC fingerprint similarity analysis. NIRS and HPLC fingerprints were of different characteristics, and the combination of the two methods can quickly and accurately identify Chrysanthemum with different processing methods. PMID:26975109

  2. Simultaneous analysis of eight bioactive compounds in Danning tablet by HPLC-ESI-MS and HPLC-UV.

    PubMed

    Liu, Runhui; Zhang, Jiye; Liang, Mingjin; Zhang, Weidong; Yan, Shikai; Lin, Min

    2007-02-19

    A high performance liquid chromatography (HPLC) coupled with electrospray tandem mass spectrometry (ESI-MS) and ultraviolet detector (UV) has been developed for the simultaneous analysis of eight bioactive compounds in Danning tablet (including hyperin, hesperidin, resveratrol, nobiletin, curcumine, emodin, chrysophanol, and physcion), a widely used prescription of traditional Chinese medicine (TCM). The chromatographic separation was performed on a ZORBAX Extend C(18) analytical column by gradient elution with acetonitrile and formate buffer (containing 0.05% formic acid, adjusted with triethylamine to pH 5.0) at a flow rate of 0.8 ml/min. The eight compounds in Danning tablet were identified and their MS(n) fractions were elucidated by using HPLC-ESI-MS, and the contents of these compounds were determined by using HPLC-UV method. The standard calibration curves were linear between 5.0 and 100 microg/ml for hyperin, 10-200 microg/ml for hesperidin, 1.0-150 microg/ml for resveratrol, 2.0-120 microg/ml for nobiletin, 2.0-225 microg/ml for curcumine, 20-300 microg/ml for emodin, 2.0-200 microg/ml for chrysophanol, and 20-250 microg/ml for physcion with regression coefficient r(2)>0.9995. The intra-day and inter-day precisions of this method were evaluated with the R.S.D. values less than 0.7% and 1.3%, respectively. The recoveries of the eight investigated compounds were ranged from 99.3% to 100.2% with R.S.D. values less than 1.5%. This method was successfully used to determine the 8 target compounds in 10 batches of Danning tablet. PMID:17079108

  3. HPLC-DAD-MS identification of bioactive secondary metabolites from Ferula communis roots.

    PubMed

    Arnoldi, Lolita; Ballero, Mauro; Fuzzati, Nicola; Maxia, Andrea; Mercalli, Enrico; Pagni, Luca

    2004-06-01

    A simple HPLC method was developed to distinguish between 'poisonous' and 'non-poisonous' chemotypes of Ferula communis. The method was performed on a C8 reverse phase analytical column using a binary eluent (aqueous TFA 0.01%-TFA 0.01% in acetonitrile) under gradient condition. The two chemotypes showed different fingerprints. The identification of five coumarins and eleven daucane derivatives by HPLC-diode array detection (HPLC-DAD) and HPLC-MS is described. A coumarin, not yet described, was detected. PMID:15158993

  4. Separation and quantitative analysis of alkyl sulfate ethoxymers by HPLC.

    PubMed

    Morvan, Julien; Hubert-Roux, Marie; Agasse, Valérie; Cardinael, Pascal; Barbot, Florence; Decock, Gautier; Bouillon, Jean-Philippe

    2008-01-01

    Separation of alkyl sulfate ethoxymers is investigated on various high-performance liquid chromatography (HPLC) stationary phases: Acclaim C18 Surfactant, Surfactant C8, and Hypercarb. For a fixed alkyl chain length, ethoxymers are eluted in the order of increasing number of ethoxylated units on Acclaim C18 Surfactant, whereas a reversed elution order is observed on Surfactant C8 and Hypercarb. Moreover, on an Acclaim C18 Surfactant column, non-ethoxylated compounds are eluted in their ethoxymers distribution and the use of sodium acetate additive in mobile phase leads to a co-elution of ethoxymers. HPLC stationary phases dedicated to surfactants analysis are evaluated by means of the Tanaka test. Surfactant C8 presents a great silanol activity whereas Acclaim C18 Surfactant shows a high steric selectivity. For alkyl sulfates, linearity of the calibration curve and limits of detection and quantitation are evaluated. The amount of sodium laureth sulfate raw material found in commercial body product is in agreement with the specification of the manufacturer. PMID:19007494

  5. Determination of ethylene thiourea in urine by HPLC-DAD.

    PubMed

    El Balkhi, Souleiman; Sandouk, Pierre; Galliot-Guilley, Martine

    2005-01-01

    Ethylene thiourea (ETU) is a metabolite of ethylenebisdithiocarbamates (EBDCs); it is the best indicator of exposure to these fungicides. Therefore, high-performance liquid chromatography with photodiode-array detection (HPLC-DAD) was optimized and validated for the determination of ETU in human urines. Urine samples were extracted by solid-phase extraction using Extrelut and analyzed using HPLC-DAD set at 231 nm. The analyses were carried out using a mobile phase of 0.01 M phosphate buffer (pH 4.5) on a C18 Uptisphere NEC-5-20, 250- x 4.6-mm x 5-microm column. The internal standard used was 4-pyridinecarboxylic acid hydrazide. The method was successfully validated in compliance with requirements set by the International Committee on Harmonization 1996. The lower limit of quantitation was at 1 microg/L, and the linearity was studied from 1 to 100 microg/L. There were 272 urine samples collected from farmers exposed to EBDCs in different regions in France analyzed in this study. PMID:15975251

  6. Spectrophotometric and HPLC determination of secnidazole in pharmaceutical tablets.

    PubMed

    El Wallily, A F; Abdine, H H; Razak, O A; Zamel, S

    2000-07-01

    Simple and accurate spectrophotometric and HPLC methods were developed for the determination of secnidazole in tablets dosage form. The first spectrophotometric method depends on the reduction of secnidazole molecule with zinc dust and hydrochloric acid followed by condensation with either p-dimethylaminobenzaldehyde or anisaldehyde to give colored chromogens having absorbance at 494 and 398 nm, respectively. The second method was based on the reaction of the drug with sodium nitroprusside in the presence or absence of hydroxylammonium hydrochloride. The formed colored chromogens were measured at 584 and 508 nm, respectively. The experimental conditions were optimized and Beer's law was obeyed over the applicable concentration ranges. The application of HPLC procedures depended on using either a conventional or microbore reverse-phase (C18) column along with mobile phases consisting of water and methanol (30:70), at pH of 3.5. Both techniques were applied successfully for the analysis of secnidazole in tablets form. The results obtained from both procedures were statistically compared using the Student's-t and F-variance ratio tests. PMID:10857557

  7. 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.

  8. HPLC analysis as a tool for assessing targeted liposome composition.

    PubMed

    Oswald, Mira; Platscher, Michael; Geissler, Simon; Goepferich, Achim

    2016-01-30

    Functionalized phospholipids are indispensable materials for the design of targeted liposomes. Control over the quality and quantity of phospholipids is thereby key in the successful development and manufacture of such formulations. This was also the case for a complex liposomal preparation composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), Cholesterol (CHO), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPE-PEG2000). To this end, an RP-HPLC method was developed. Detection was done via evaporative light scattering (ELS) for liposomal components. The method was validated for linearity, precision, accuracy, sensitivity and robustness. The liposomal compounds had a non-linear quadratic response in the concentration range of 0.012-0.42 mg/ml with a correlation coefficient greater than 0.99 with an accuracy of method confirmed 95-105% of the theoretical concentration. Furthermore, degradation products from the liposomal formulation could be identified. The presented method was successfully implemented as a control tool during the preparation of functionalized liposomes. It underlined the benefit of HPLC analysis of phospholipids during liposome preparation as an easy and rapid control method for the functionalized lipid at each preparation step as well as for the quantification of all components. PMID:26570988

  9. Determination of capsinoids by HPLC-DAD in capsicum species.

    PubMed

    Singh, Satyavan; Jarret, Robert; Russo, Vincent; Majetich, George; Shimkus, Joel; Bushway, Rodney; Perkins, Brian

    2009-05-13

    Capsicum fruits contain a newly discovered phytochemical called capsinoids. Because little is known about the quantities of these compounds in both sweet and pungent pepper fruits, a high-performance liquid chromatography (HPLC) method was developed to identify and quantify the capsinoids (naturally present E-capsiate and dihydrocapsiate) utilizing fruit obtained from a variety of Capsicum spp. in the U.S. Department of Agriculture's Capsicum germplasm collection. Capsinoids were extracted with acetonitrile, filtered, and analyzed using an HPLC system equipped with a C(18) monolithic column, gradient pump, and diode array detector. The elution solvents were acetonitrile and water (60:40) with an isocratic flow rate of 1.0 mL/min. Forty-nine samples representing distinct morphotypes of four cultivated species ( C. annuum var. annuum, C. annuum var. glabriusculum, C. baccatum , C. chinense , and C. frutescens ) contained detectable levels (11-369 microg/g) of E-capsiate quantified at a wavelength of 280 nm. Nine of the E-capsiate-containing samples also had dihydrocapsiate (18-86 micro/g). Gas chromatography with a mass spectrometry detector (GC-MS) confirmed the presence of these compounds in the Capsicum spp. PMID:19415923

  10. HPLC assisted Raman spectroscopic studies on bladder cancer

    NASA Astrophysics Data System (ADS)

    Zha, W. L.; Cheng, Y.; Yu, W.; Zhang, X. B.; Shen, A. G.; Hu, J. M.

    2015-04-01

    We applied confocal Raman spectroscopy to investigate 12 normal bladder tissues and 30 tumor tissues, and then depicted the spectral differences between the normal and the tumor tissues and the potential canceration mechanism with the aid of the high-performance liquid chromatographic (HPLC) technique. Normal tissues were demonstrated to contain higher tryptophan, cholesterol and lipid content, while bladder tumor tissues were rich in nucleic acids, collagen and carotenoids. In particular, β-carotene, one of the major types of carotenoids, was found through HPLC analysis of the extract of bladder tissues. The statistical software SPSS was applied to classify the spectra of the two types of tissues according to their differences. The sensitivity and specificity of 96.7 and 66.7% were obtained, respectively. In addition, different layers of the bladder wall including mucosa (lumps), muscle and adipose bladder tissue were analyzed by Raman mapping technique in response to previous Raman studies of bladder tissues. All of these will play an important role as a directive tool for the future diagnosis of bladder cancer in vivo.

  11. [Determination of furbenicillin sodium and its related substances by HPLC].

    PubMed

    Chang, Yan; Tian, Ye; Ma, Yue; Hu, Chang-qin

    2015-12-01

    Furbenicillin is a broad-spectrum semisynthetic penicillin with strong antibacterial activity against Gram-negative bacteria. Furbenicillin sodium is determined by volumetric method in current criteria. However, the criteria does not contain an assay of related substances of furbenicillin sodium. In this study, we established a method for detection and analysis of furbenicillin sodium and its related substances by HPLC. The analysis was performed with a C18 column under a gradient elution, the detection wavelength was 225 nm, and the column temperature was 35 degrees C. The reliability and accuracy of established method was validated in this study. Pure samples of furbenicillin sodium and its related substances were prepared. The structures, biological activities, and chromatographic retention behaviors of furbenicillin sodium and its related substances were identified using NMR, CLSI agar dilution method, and HPLC. All results in the current study provide ample evidence that this method is able to determine the reasonable limits in the quality-control protocol for furbenicillin sodium. PMID:27169288

  12. Selenite biotransformation during brewing. Evaluation by HPLC-ICP-MS.

    PubMed

    Sánchez-Martínez, Maria; da Silva, Erik Galvão P; Pérez-Corona, Teresa; Cámara, Carmen; Ferreira, Sergio L C; Madrid, Yolanda

    2012-01-15

    Yeast (Saccharomyces cerevisiae) and lactic bacteria have shown their ability to accumulate and transform inorganic selenium into organo Se compounds. The objective of this work was to evaluate selenium biotransformation during brewing by using S. cerevisiae and Saccharomyces uvarum for Ale and Lager fermentation, respectively. Se-enriched beer was produced by the addition of sodium selenite (0, 0.2, 1.0, 2.0, 10.0, 20.0 μg Se mL(-1), respectively) to the fermentation media composed of yeast, malt extract and water. The alcoholic fermentation process was not affected by the presence of selenium regardless of the type of Saccharomyces being used. The percentage of selenium incorporated into beer, added between 1.0 and 10 μg mL(-1) was 55-60% of the selenium initially present. Se-compounds in post-fermentation (beer and yeast) products were investigated by using an analytical methodology based on HPLC-ICP-MS. For this purpose, several sample treatments, including ultrasonic-assisted enzymatic hydrolysis, in conjunction with different separation mechanisms like dialysis and anion exchange HPLC chromatography were applied for unambiguously identifying Se-species that produce during brewing. Selenomethionine was the main selenium compound identified in beer and yeast, being this species in the only case of the former not associated to peptides or proteins. PMID:22265498

  13. Quantitation of glucosamine from shrimp waste using HPLC.

    PubMed

    López-Cervantes, J; Sánchez-Machado, D I; Delgado-Rosas, K E

    2007-04-01

    This work presents a high-performance liquid chromatography (HPLC) method for the quantitation of glucosamine in chitin. The method includes an acid hydrolysis of chitin. The chromatographic separation is achieved using a Hypersil ODS 5-microm column (250 x 4.6 mm) at 38 degrees C, with precolumn derivatization with 9-fluorenylmethyl-chloroformate and UV detection (lambda = 264 nm). The mobile phase is a mixture of mobile phase A [30 mM ammonium phosphate (pH 6.5) in 15:85 methanol-water (v/v)], mobile phase B [15:85 methanol-water (v/v)], and mobile phase C [90:10 acetonitrile-water (v/v)], with a flow rate of 1.2 mL/min. The HPLC method proposed showed adequate repeatability (relative standard deviation, 5.8%), accuracy (92.7% recovery), and sensitivity, with a detection limit of 2 microg/mL. The method is successfully applied to the quantitation of glucosamine for the determination of the purity of chitin from shrimp waste. PMID:17504567

  14. Evaluation of TEGDMA leaching from four resin cements by HPLC

    PubMed Central

    Altintas, Subutay Han; Usumez, Aslihan

    2012-01-01

    Objective The aim of this study was to evaluate the elution of TEGDMA from dual cured resin cements, used for bonding of ceramic restoration by high performance liquid chromatography (HPLC). Methods: Forty freshly extracted caries and restoration free molar teeth used in this study. Standardized Class I preparations were prepared in all teeth. Ceramic inlays were cemented with one of the dual cured resin cements (Variolink II, Rely X ARC, Rely X Unicem and Resilute). After cementation, specimens were stored in 75% ethanol solution. HPLC was used to analyze the amounts of TEGDMA in different time intervals. Two-way ANOVA and Tukey HSD tests were used to evaluate the results (P<.05). Results: The amount of TEGDMA eluted from Resilute was the highest and the amount of TEG-DMA eluted from Rely X Unicem was the lowest (P<.05). The total amount of monomers was the highest after 21 days (P<.05). Conclusion: In the case of resin cements, elution of TEGDMA was the highest in Resilute and lowest in Rely X Unicem. The amount of TEGDMA eluted from resin cements was influenced by the time. PMID:22904653

  15. Determination of some psychotropic drugs in serum and saliva samples by HPLC-DAD and HPLC MS.

    PubMed

    Petruczynik, A; Wróblewski, K; Szultka-Młyńska, M; Buszewski, B; Karakuła-Juchnowicz, H; Gajewski, J; Morylowska-Topolska, J; Waksmundzka-Hajnos, M

    2016-08-01

    A simple, rapid and sensitive HPLC-DAD method has been developed and validated for the simultaneous determination of seven psychotropic drugs (risperidone, citalopram, clozapine,quetiapine, levomepromazine, perazine and aripiprazole) in human serum or saliva samples. The chromatographic analyses were performed on a XSELECT CSH Phenyl-Hexyl column with a mobile phase containing methanol, acetate buffer at pH 3.5 and 0.025mL(-1) diethylamine. The influence of concentration of methanol in injection samples and injection volume on peak symmetry and system efficiency was examined.The full separation of all investigated drugs, good peaks' symmetry and simultaneously high systems efficiency were obtained in applied chromatographic system. The method is suitable for the analysis of investigated drugs in human plasma or saliva for psychiatric patients for control of pharmacotherapy, particularly in combination therapy. HPLC-MS was applied for verification of the presence of drugs and their metabolites in serum and saliva samples from patients. PMID:26809494

  16. Characterization and quantitation of anthocyanins in purple-fleshed sweet potatoes cultivated in Korea by HPLC-DAD and HPLC-ESI-QTOF-MS/MS.

    PubMed

    Lee, Mi Jin; Park, Jeong Seob; Choi, Dong Seong; Jung, Mun Yhung

    2013-03-27

    The characterization and quantitative analysis of anthocyanins in four purple-fleshed sweet potato varieties (Borami, Mokpo 62, Shinzami, and Zami) cultivated in Korea were carried out by HPLC/diode array detector (DAD), HPLC-TOF/MS, and HPLC-MS/MS analyses. For the identification of anthocyanins, molecular formulas were first calculated by using the exact mass data of the molecular ions ([M](+)). The patterns of isotope ions of M(+) were also monitored to confirm the assignment of the molecular formulas. HPLC-MS(2) analysis was further conducted for elucidating their molecular structures. Twenty-seven different anthocyanins were tentatively identified in the sweet potatoes. Six of them are the first reported in sweet potatoes roots. The quantity and profiles of anthocyanins in sweet potatoes varied greatly with variety. Borami was found, for the first time, to be a rare sweet potato variety with an exceptionally high quantity of pelargonidin-based anthocyanins. PMID:23464823

  17. Chemical Profiling (HPLC-NMR & HPLC-MS), Isolation, and Identification of Bioactive Meroditerpenoids from the Southern Australian Marine Brown Alga Sargassum paradoxum

    PubMed Central

    Brkljača, Robert; Urban, Sylvia

    2014-01-01

    A phytochemical investigation of a southern Australian marine brown alga, Sargassum paradoxum, resulted in the isolation and identification of four new (5, 9, 10, and 15) and nine previously reported (1, 2, 6–8, and 11–14) bioactive meroditerpenoids. HPLC-NMR and HPLC-MS were central to the identification of a new unstable compound, sargahydroquinal (9), and pivotal in the deconvolution of eight (1, 2, 5–7, and 10–12) other meroditerpenoids. In particular, the complete characterization and identification of the two main constituents (1 and 2) in the crude dichloromethane extract was achieved using stop-flow HPLC-NMR and HPLC-MS. This study resulted in the first acquisition of gHMBCAD NMR spectra in the stop-flow HPLC-NMR mode for a system solely equipped with a 60 μL HPLC-NMR flow cell without the use of a cold probe, microcoil, or any pre-concentration. PMID:25551779

  18. Scientific achievements of Jack Kirkland to the development of HPLC and in particular to HPLC silica packings--a personal perspective.

    PubMed

    Unger, Klaus K

    2004-12-10

    Joseph (Jack) Kirkland is one of the outstanding protagonists of modern column liquid chromatography (HPLC). He started in 1953 as an analytical chemist at the Experimental Station of Du Pont de Nemours & Co, Wilmington, Delaware, analyzing pesticides by gas chromatography (GC). He early recognized the potential of HPLC as a powerful separation technique at the end of 1960. His major contributions to HPLC were in the field of silica based packings and stationary phases. At the beginning of the 1970's he manufactured Porous Layer Beads and later microparticulate porous silicas based at the Zorbax technology. He made outstanding contributions in the field of instrument design for HPLC and in the field of Sedimentation Field Flow Fractionation (SFFF), in HPLC method development and optimization strategies. In 1992 Jack resigned from Du Pont de Nemours & Co, Wilmington, Delaware, and joined Rockland Technologies, Newport, Delaware, as a Director of Research and Development. During this period he successfully developed a series of novel, designed reversed phase silicas. He resigned from Rockland technologies, now Agilent Technologies, Newport, Delaware, in 2001, but always remained dedicated to HPLC. PMID:15628148

  19. Quantification of the molecular species of tetraacylglycerols in lesquerella (Physaria fendleri) Oil by HPLC and MS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirteen molecular species of tetraacylglycerols in the seed oil of Physaria fendleri were recently identified. We report here the quantification of these tetraacylglycerols using HPLC with evaporative light scattering detector and the MS of the HPLC fractions. Ion signal intensities of MS1 from th...

  20. Ellagitannin Composition of Blackberry As Determined by HPLC-ESI-MS and MALDI-TOF-MS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Apache blackberries (Rubus sp.) were evaluated by HPLC-MS and MALDI-TOF-MS to identify ellagitannins present in the flesh, torus (receptacle tissue), and seeds. Most ellagitannins were only present or detectable in seed tissues. Ellagitannins identified by HPLC-MS in the seeds included pedunculagi...

  1. Chiral HPLC separation and CD spectra of the enantiomers of the alkaloid tacamonine and related compounds.

    PubMed

    Caccamese, S; Principato, G; Jokela, R; Tolvanen, A; Din Belle, D

    2001-01-01

    The HPLC enantiomeric separation of racemic indole alkaloids tacamonine, 17 alpha-hydroxytacamonine, deethyleburnamonine, and vindeburnol was accomplished using Chiralpak AD and Chiralcel OD as chiral stationary phases. Small structural differences affect the enantioselectivity ability of these phases. Single enantiomers of tacamonine and vindeburnol were isolated by semipreparative HPLC and their CD spectra and optical rotations were measured. PMID:11746802

  2. Size exclusion HPLC of proteins for evaluation of durum wheat quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The present research aimed to assess size exclusion HPLC (SE-HPLC) in protein molecular weight distribution determination for quality evaluation of durum semolina. Semolina samples were milled from 13 durum genotypes grown at 7 locations in 2009 and 2010 in ND. Sodium dodecyl sulfate (SDS) buffer ...

  3. Fatty acids in erythrocytes measured by isocratic HPLC.

    PubMed

    Abushufa, R; Reed, P; Weinkove, C

    1994-09-01

    We developed an isocratic reversed-phase HPLC method to measure arachidonic, palmitoleic, linoleic, eicosatrienoic, oleic, palmitic, and stearic acids from hydrolyzed erythrocytes. Washed erythrocytes were heated in methanol:HCl and the fatty acids extracted into hexane:amyl alcohol. After derivatization with 4-bromomethyl-7-methoxycoumarin, samples diluted in mobile phase (acetonitrile:water, 85:15 by vol) were injected onto a 250 x 4.6 mm C18 column, and the eluted fatty acids were detected fluorometrically. For all analytes, the mean within-batch CV was 8.2% (5.5-10.8%), the mean limit of detection was 7.0 mumol/L, a linear response was maintained up to 400 mumol/L, and results agreed well with those by gas chromatography. The addition of antioxidant (butylated hydroxytoluene) was essential for sample stability. We discuss hydrolysis and extraction times, derivatization temperature, critical steps in chromatography, and concentration units. PMID:8070079

  4. 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.

  5. HPLC Estimation of berberine in Tinospora cordifolia and Tinospora sinensis.

    PubMed

    Srinivasan, G V; Unnikrishnan, K P; Rema Shree, A B; Balachandran, Indira

    2008-01-01

    A high-performance liquid chromatographic method for the estimation of berberine in the stem of Tinospora cordifolia (Willd.) Miers. ex Hook.f. and Thoms. and Tinospora sinensis (Lour.) Merrill is described. The dried stems of T. cordifolia and T. sinensis were defatted with petroleum ether (60-80 degrees ). The marc was dried and further extracted with methanol. The concentration of berberine in methanol extract was determined using a C-18 reverse phase column with a mobile phase of acetonitrile:water (10:90 v/v) at a flow rate of 0.6 ml/min and with UV detection at 266 nm. TLC and HPLC comparison of both the species revealed significant variation in the chemical constitution of the two species. This observation becomes important in the context of the use of T. sinensis in place of the genuine drug T. cordifolia. PMID:20390090

  6. HPLC Estimation of berberine in Tinospora cordifolia and Tinospora sinensis

    PubMed Central

    Srinivasan, G. V.; Unnikrishnan, K. P.; Rema Shree, A. B.; Balachandran, Indira

    2008-01-01

    A high-performance liquid chromatographic method for the estimation of berberine in the stem of Tinospora cordifolia (Willd.) Miers. ex Hook.f. and Thoms. and Tinospora sinensis (Lour.) Merrill is described. The dried stems of T. cordifolia and T. sinensis were defatted with petroleum ether (60-80°). The marc was dried and further extracted with methanol. The concentration of berberine in methanol extract was determined using a C-18 reverse phase column with a mobile phase of acetonitrile:water (10:90 v/v) at a flow rate of 0.6 ml/min and with UV detection at 266 nm. TLC and HPLC comparison of both the species revealed significant variation in the chemical constitution of the two species. This observation becomes important in the context of the use of T. sinensis in place of the genuine drug T. cordifolia. PMID:20390090

  7. HPLC analysis and cytotoxic activity of Vernonia cinerea.

    PubMed

    Khay, Mom; Toeng, Phirom; Mahiou-Leddet, Valérie; Mabrouki, Fathi; Sothea, Kim; Ollivier, Evelyne; Elias, Riad; Bun, Sok-Siya

    2012-10-01

    The extracts of five Cambodian medicinal plants (Aganosma marginata, Dracaena cambodiana, Harrisonia perforata, Hymenodictyon excelsum and Vernonia cinerea) were evaluated in vitro for their cytotoxic activity against HT29 colon adenocarcinoma cells and HepG2 hepatoma cells, using the MTT assay. Among these five plants, Vernonia cinerea displayed potent cytotoxicity. One main sesquiterpene lactone, 8alpha-tigloyloxy-hirsutinolide-13-O-acetate was isolated from the whole plant of V. cinerea. This compound was active against both cancer cell lines (IC50 = 3.50 microM for HT29 and IC50 = 4.27 microM for HepG2). To quantify this compound in the plant, an analytical high-performance liquid chromatography (HPLC) method was developed and validated. PMID:23156983

  8. Quantitative and qualitative HPLC analysis of thermogenic weight loss products.

    PubMed

    Schaneberg, B T; Khan, I A

    2004-11-01

    An HPLC qualitative and quantitative method of seven analytes (caffeine, ephedrine, forskolin, icariin, pseudoephedrine, synephrine, and yohimbine) in thermogenic weight loss preparations available on the market is described in this paper. After 45 min the seven analytes were separated and detected in the acetonitrile: water (80:20) extract. The method uses a Waters XTerra RP18 (5 microm particle size) column as the stationary phase, a gradient mobile phase of water (5.0 mM SDS) and acetonitrile, and a UV detection of 210 nm. The correlation coefficients for the calibration curves and the recovery rates ranged from 0.994 to 0.999 and from 97.45% to 101.05%, respectively. The qualitative and quantitative results are discussed. PMID:15587578

  9. Multiresidue HPLC methods for phenyl urea herbicides in water.

    PubMed

    Ruberu, S R; Draper, W M; Perera, S K

    2000-09-01

    High-performance liquid chromatography (HPLC) methods for the determination of phenyl urea herbicides in water are described. The target compounds include chlortoluron, diuron, fluometuron, isoproturon, linuron, metobromuron, metoxuron, monuron, neburon, and siduron. Water was subjected to solid phase extraction (SPE) using either automated SPE with 47 mm C(18) Empore disks or on-line precolumn concentration. Herbicides were separated on a C(18) reversed phase column with an acetonitile-water gradient and were detected with either a diode array detector (DAD) or a postcolumn photolysis and derivatization (PPD) detector system. Photolysis converted the phenyl ureas to monoalkylamines that were derivatized to fluorescent isoindoles by reaction with o-phthalaldehyde and 2-mercaptoethanol. The DAD monitoring at 245 nm was linear over three decades with instrument detection limits of approximately 0.01 mg/L. SPE efficiency was between 48 and 70% in laboratory reagent water, but use of the internal standard quantitation method improved accuracy. High total dissolved solids and total organic carbon values in surface water improved recoveries relative to laboratory reagent water for all of the phenyl ureas. In Colorado River water spiked at 1 or 50 microg/L, mean recoveries ranged from 74 to 104%. Method detection limits (MDLs) ranged from 4 to 40 ng/L (parts per trillion) with the DAD instrument. PPD detection was highly specific but resulted in a slight loss in chromatographic efficiency and average MDLs approximately 5 times higher using a single set of detection conditions. The study indicates that methods based on SPE followed by HPLC with diode array or PPD detection have practical utility for trace analysis of phenyl ureas in drinking water or surface waters. PMID:10995323

  10. Study of RP HPLC Retention Behaviours in Analysis of Carotenoids.

    PubMed

    Ligor, M; Kováčová, J; Gadzała-Kopciuch, R M; Studzińska, S; Bocian, Sz; Lehotay, J; Buszewski, B

    2014-01-01

    For determination of selected carotenoids, various types of columns for high-performance liquid chromatography (HPLC) with different properties have been used. The characteristics of the laboratory-used packing material containing monomeric alkyl-bonded phases (C18, C30) and phenyl as well as phenyl-hexyl stationary phases were studied. The retention data of the examined compounds were used to determine the hydrophobicity and silanol activity of stationary phases applied in the study. The presence of the polar and carboxyl groups in the structure of the bonded ligand strongly influences the polarity of the stationary phase. Columns were compared according to methylene selectivity using a series of benzene homologues. The measurements were done using a methanol-water mobile phase. Knowledge of the properties of the applied stationary phase provided the possibility to predict the RP HPLC retention behaviours in analysis of carotenoids including lutein, lycopene and β-carotene. The composition of the mobile phase, the addition of triethylamine and the type of stationary phase had been taken into account in designing the method of carotenoid identification. Also a monolithic column characterised by low hydrodynamic resistance, high porosity and high permeability was applied. The presented results show that the coverage density of the bonded ligands on silica gel packings and length of the linkage strongly influence the carotenoid retention behaviours. In our study, the highest retention parameters for lutein, lycopene and β-carotene were observed for C30 and C18 stationary phase. This effect corresponds with pore size of column packing greater than 100 Å and carbon content higher than 11 %. PMID:25089049

  11. Spectroscopic and HPLC studies of photodegradation of nilvadipine.

    PubMed

    Augustyniak, W; Mielcarek, J; Milewski, M; Szamburska, O

    2001-11-01

    Photochemical decomposition of nilvadipine (NV), a derivative of 1,4-dihydropyridine (DHP), was studied. Photodegradation was carried out in the conditions recommended in the first version of the document issued by the International Conference on Harmonization (ICH), currently in force in the studies of photochemical stability of drugs and therapeutic substances. Methanol solutions of NV were irradiated with a high-pressure mercury arc lamp, type HBO 200 (300-400 nm). The maximum absorption of radiation at 365 nm was achieved by applying the interference filter and Wood's filter. The assessment of NV photodegradation was made on the basis of the UV spectrophotometric and high-performance liquid chromatographic (HPLC) methods. Quantitatively, the process was described with the calculated rate constants of decomposition k, time of decomposition of 50% of the compound to 5, and time of decomposition of 10% of the compound t(0.1). The two methods applied allowed a determination of the kinetic parameters of NV photodegradation from the relationship ln c = f(t). Using the Reinecke salt as a chemical actinometer, apparent quantum yields of photodegradation were obtained; after extrapolation to the time of irradiation zero, these gave the actual quantum yield (phi = 7.3 10(-5)). The quantum yield of fluorescence at lambda(exc) = 375 nm was about 9.3 x 10(-4) The methods used for evaluation of NV photodegradation were subjected to validation, and results of the analytical methods were statistically assessed by Snedecor F and Student t tests. The former test revealed no statistically significant difference between the variances obtained by the HPLC and UV spectrophotometric methods. Also, verification of the zero hypothesis of the Student t test on equality of means of the results obtained gave no significant diferences between the two methods. PMID:11794805

  12. Identification of Rhodiola species by using RP-HPLC*

    PubMed Central

    Wang, Qiang; Ruan, Xiao; Jin, Zhi-hua; Yan, Qi-chuan; Tu, Shan-jun

    2005-01-01

    An approach was established using RP-HPLC (reversed-phase high-performance liquid chromatography) to identify ten species of Rhodiola, R. coccinea A. Bor, R. junggarica C.Y. Yang et N.R. Cui spn., R. heterodonta A. Bor, R. linearifolia A. Bor, R. pamiro alaiucm A. Bor, R. kaschgarica A. Bor, R. litwinowii A. Bor, R. gelida schrenk, R. rosea L. and R. quadrifide Fisch et Mey collected from the Tianshan Mountains areas of China. Chromatograms of alcohol-soluble proteins, generated from these ten Rhodiola spp. were compared. Each chromatogram of alcohol-soluble proteins came from a single seed of one wild species only. The results showed that when using a Waters Delta Pak. C18, 5 μm particle size reversed phase column (150 mm×3.9 mm), a linear gradient of 22%–55% solvent B with a flow rate of 1 ml/min and a run time of 67 min, the chromatography gave optimum separation of Rhodiola alcohol-soluble proteins. Chromatogram of each species was different and could be used to identify those species. Cluster analysis of genetic similarity coefficients of 37% to 60% showed a medium degree of genetic diversity among the species in these eco-areas. Cluster analysis showed that the ten species of Rhodiola can be divided into four clusters and yielded the general and unique biochemical markers of these species. RP-HPLC was shown to be a rapid, repeatable and reliable method for Rhodiola species identification and analysis of genetic diversity. PMID:15909330

  13. Quantitative determination and pattern recognition analyses of bioactive marker compounds from Dipsaci Radix by HPLC.

    PubMed

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

    2013-11-01

    In this study, quantitative and pattern recognition analyses were developed using HPLC/UV for the quality evaluation of Dipsaci Radix. For quantitative analysis, five major bioactive compounds were assessed. The separation conditions employed for HPLC/UV were optimized using ODS C18 column (250 × 4.6 mm, 5 μm) with a gradient of acetonitrile and water as the mobile phase at a flow rate of 1.0 mL/min and a detection wavelength of 212 nm. These methods were fully validated with respect to linearity, accuracy, precision, recovery, and robustness. The HPLC/UV method was applied successfully to the quantification of five major compounds in the extract of Dipsaci Radix. The HPLC analytical method for pattern recognition analysis was validated by repeated analysis of 17 Dipsaci Radix and four Phlomidis Radix samples. The results indicate that the established HPLC/UV method is suitable for quantitative analysis. PMID:23877237

  14. Validated HPLC and Ultra-HPLC Methods for Determination of Dronedarone and Amiodarone Application for Counterfeit Drug Analysis.

    PubMed

    El-Bagary, Ramzia I; Elkady, Ehab F; Mowaka, Shereen; Attallah, Maria

    2015-01-01

    Two simple, accurate, and precise chromatographic methods have been developed and validated for the determination of dronedarone (DRO) HCl and amiodarone (AMI) HCl either alone or in binary mixtures due to the possibility of using AMI as a counterfeit of DRO because of its lower price. First, an RP-HPLC method is described for the simultaneous determination of DRO and AMI. Chromatographic separation was achieved on a BDS Hypersil C18 column (150×4.6 mm, 5 μm). Isocratic elution based on potassium dihydrogen phosphate buffer with 0.1% triethylamine pH 6-methanol (10+90, v/v) at a flow rate of 2 mL/min with UV detection at 254 nm was performed. The second method is RP ultra-HPLC in which the chromatographic separation was achieved on an AcclaimTM RSLC 120 C18 column (100×2.1 mm, 2.2 μm) using isocratic elution with potassium dihydrogen phosphate buffer with 0.1% triethylamine pH 6-methanol (5+95, v/v) at a flow rate of 1 mL/min with UV detection at 254 nm. Linearity, accuracy, and precision of the two methods were found to be acceptable over the concentration ranges of 5-80 μg/mL for both DRO and AMI. The results were statistically compared using one-way analysis of variance. The optimized methods were validated and proved to be specific, robust, precise, and accurate for the QC of the drugs in their pharmaceutical preparations. PMID:26651561

  15. [Quality assessment for sustained release pharmaceutical preparations by dissolution test using microdialysis-HPLC method].

    PubMed

    Nagai, Noriaki; Murao, Takatoshi; Inubuse, Rino; Konishi, Nahoko; Ito, Yoshimasa

    2011-04-01

    Dissolution testing is a core performance test in pharmaceutical development and quality control. The conventional HPLC dissolution method (batch-sampling method) has many steps such as the filtration, collection and replenishment of sample solutions. We previously reported the dissolution test by using microdialysis methods (microdialysis-HPLC method) that can omit many steps. In this study, we investigated whether the microdialysis-HPLC method can be applied to quality assessment for sustained release preparations by a dissolution test. Calcium-channel blockers nifedipine tablets (20 mg) were used, and the test solution used was 0.2 M hydrogen phosphate-citric acid buffer (pH 6.8) with or without 1% sodium lauryl sulfate. In both test solutions, the microdialysis-HPLC method is able to accomplish continuous sampling of sample solutions, and the dissolution behaviors of original nifedipine tablets by the microdialysis-HPLC method were similar to that of the batch-sampling method. In contrast, the dissolution behaviors by the microdialysis-HPLC method were different between original nifedipine tablets and generic products, and the dissolution behaviors in the microdialysis-HPLC method tend to reflect the pharmaceutical design in comparison with the batch-sampling method. In addition, standard deviation in the microdialysis-HPLC method was lower than that of the batch-sampling method. We found that the recovery rate of nifedipine by the microdialysis-HPLC method was increased with the decrease in flow rate through dialysis probe. These findings provide significant information that can be used in pharmaceutical development and quality assessment for original and generic pharmaceutical products, which are sustained release preparations. PMID:21467802

  16. [Establishment of hepatocyte extraction combined with HPLC(HE-HPLC) and application in analysis of active components in the fruits of Gardenia jasminoides extract].

    PubMed

    Hong, Min; Ma, Hongyu; Zhu, Quan

    2009-02-01

    To screen effective principles from traditional Chinese medicine, a method named hepatocyte extraction combined with HPLC (HE-HPLC) was establish in this study. The active principles in the fruits of Gardenia jasminoides Ellis extract were combined with the hepatocytes under imitated physiological environments. Then the unattached substances were washed off by PBS with pH 7.4. After that the conjugated compounds were eluted by PBS with pH 4.0. These compounds released from target sites were collected and handled through SPE to be condensed, and analyzed by HPLC. The results indicated that two characteristic active compounds in the fruits of G. jasminoides extract binded to the hepatocytes. One of them is geniposide. The other is continued to be identified. It is showed that active principles which could bind to hepotocyte (through receptors, Channels, enzymes, etc.) could be detected, at least partly, by HE-HPLC analysis. There was a significant correlation between the retention properties of the active compounds which was obtained by HE-HPLC and their pharmacological effects on hepotocytes. PMID:19459310

  17. Electrochemically Pretreated Carbon Microfiber Electrodes as Sensitive HPLC-EC Detectors

    PubMed Central

    Bartosova, Zdenka; Riman, Daniel; Jakubec, Petr; Halouzka, Vladimir; Hrbac, Jan; Jirovsky, David

    2012-01-01

    The paper focuses on the analysis and detection of electroactive compounds using high-performance liquid chromatography (HPLC) combined with electrochemical detection (EC). The fabrication and utilization of electrochemically treated carbon fiber microelectrodes (CFMs) as highly sensitive amperometric detectors in HPLC are described. The applied pretreatment procedure is beneficial for analytical characteristics of the sensor as demonstrated by analysis of the model set of phenolic acids. The combination of CFM with separation power of HPLC technique allows for improved detection limits due to unique electrochemical properties of carbon fibers. The CFM proved to be a promising tool for amperometric detection in liquid chromatography. PMID:22654586

  18. Simultaneous determination of synthetic colorants in yogurt by HPLC.

    PubMed

    de Araújo Siqueira Bento, Waleska; Lima, Bruno Parente; Paim, Ana Paula S

    2015-09-15

    This article reports on a method to determine synthetic dyes in yogurts and milk drinks. Initially a method for extraction of artificial dyes was developed to pretreat samples in order to extract most of the artificial colorants. Then, the colorants were analyzed by HPLC-PAD using gradient elutions. The method was linear in the range of 0.5-25mgL(-1) colorants (0.9991

  19. Identifying indoor environmental patterns from bioaerosol material using HPLC

    PubMed Central

    Staton, Sarah J. R.; Castillo, Josemar A.; Taylor, Thomas J.; Herckes, Pierre; Hayes, Mark A.

    2012-01-01

    A substantial portion of the atmospheric particle budget is of biological origin (human and animal dander, plant and insect debris, etc.). These bioaerosols can be considered information-rich packets of biochemical data specific to the organism of origin. In this study, bioaerosol samples from various indoor environments were analyzed to create identifiable patterns attributable to a source level of occupation. Air samples were collected from environments representative of human high-traffic and low-traffic indoor spaces along with direct human skin sampling. In all settings, total suspended particulate matter (TSP) was collected and the total aerosol protein concentration ranged from 0.03–1.2 μg/m3. High performance liquid chromatography (HPLC) was chosen as a standard analysis technique for the examination of aqueous aerosol extracts to distinguish signatures of occupation compared to environmental background. The results of this study suggest that bioaerosol “fingerprinting” is possible with the two test environments being distinguishable at a 97% confidence interval. PMID:23092966

  20. Simultaneous determination of 12 coumarins in bamboo leaves by HPLC.

    PubMed

    Wang, Shuying; Tang, Feng; Yue, Yongde; Yao, Xi; Wei, Qi; Yu, Jin

    2013-01-01

    A simple, rapid, and sensitive HPLC-UV method was developed for qualitative and quantitative analysis of 12 coumarin compounds (skimin, scopolin, scopoletin, umbelliferone, 6,7-dimethoxycoumarin, coumarin, psoralen, xanthotoxin, 5,7-dimethoxycoumarin, pimpinellin, imperatorin, and osthole) in bamboo leaves. The samples were extracted with ethanol-water (70 + 30, v/v) by ultrasonication and purified by Florisil SPE. The method was validated for linearity, LOD, LOQ, accuracy, precision, and recovery. The standard curves in the corresponding ranges had good linearity. LOD was at the range of 0.19 to 0.85 mglkg and LOQ 0.64 to 2.82 mg/kg. The values of RSD for accuracy and intraday and interday precision were less than 3%, except for 6,7-dimethoxycoumarin. Recoveries from spiked samples at 30, 20, and 10 mg/kg in Dendrocalamus giganteus Munro were higher than 70%, except for scopoletin, 6,7-dimethoxycoumarin, and coumarin. The method was validated using field-collected samples taken from Beijing and Changning Counties, SiChuan, China. Six coumarins, namely, skimin, scopolin, scopoletin, umbelliferone, coumarin, and pimpinellin, were found in the extracts of 11 species of bamboo leaves. The concentrations of total coumarins were in the range of 8.67 to 99.2 mg/kg. The maximum concentration of total coumarins was found in Bambusa pervariabilis, and the minimum was in PMID:24282929

  1. HPLC retention thermodynamics of grape and wine tannins.

    PubMed

    Barak, Jennifer A; Kennedy, James A

    2013-05-01

    The effect of grape and wine tannin structure on retention thermodynamics under reversed-phase high-performance liquid chromatography conditions on a polystyrene divinylbenzene column was investigated. On the basis of retention response to temperature, an alternative retention factor was developed to approximate the combined temperature response of the complex, unresolvable tannin mixture. This alternative retention factor was based upon relative tannin peak areas separated by an abrupt change in solvent gradient. Using this alternative retention factor, retention thermodynamics were calculated. Van't Hoff relationships of the natural log of the alternative retention factor against temperature followed Kirchoff's relationship. An inverse quadratic equation was fit to the data, and from this the thermodynamic parameters for tannin retention were calculated. All tannin fractions exhibited exothermic, spontaneous interaction, with enthalpy-entropy compensation observed. Normalizing for tannin size, distinct tannin compositional effects on thermodynamic parameters were observed. The results of this study indicate that HPLC can be valuable for measuring the thermodynamics of tannin interaction with a hydrophobic surface and provides a potentially valuable alternative to calorimetry. Furthermore, the information gathered may provide insight into understanding red wine astringency quality. PMID:23565723

  2. Application of HPLC in the 32P-postlabeling assay.

    PubMed

    Gorelick, N J

    1993-07-01

    The postlabeling procedure for the detection of DNA modifications entails enzyme-catalyzed incorporation of 32P into nucleotides and chromatographic separation of radiolabeled products for quantification. Alternate versions of this procedure have been developed which vary in sensitivity and in applicability for the detection of different DNA adducts. Methods that utilize HPLC in either of two steps in the procedure (i.e., the separation of modified and unmodified nucleotides before the labeling reaction or the resolution of 32P-labeled adducts) are applicable for the detection of alkyl adducts as well as bulky, hydrophobic adducts and are discussed in this review. In some cases, postlabeling assays have been tailored for the quantitative detection of specific adducts. Use of multiple optimized postlabeling methods to analyze one DNA sample may enable identification of multiple specific adducts in human DNA. The widest and most promising applications for adduct detection with the postlabeling assay are for previously characterized adducts, where adduct standards are available for optimization and characterization of recovery in the assay. 32P-Postlabeling is a powerful way to measure DNA adducts as it is very sensitive. However, caution should be applied in drawing conclusions from postlabeling studies without appropriate corroborative data using another adduct detection method or without appropriate method development preceding the study. Examples of applications in human, laboratory animal, and environmental studies are available. PMID:7686266

  3. 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

  4. Impurity profiling of ibandronate sodium by HPLC-CAD.

    PubMed

    Wahl, Oliver; Holzgrabe, Ulrike

    2015-10-10

    The modern bisphosphonate drug ibandronate sodium, a challenging candidate for impurity profiling, was analyzed using high performance liquid chromatography (HPLC) combined with corona charged aerosol detection (CAD). Separation was achieved on a mixed mode column combining hydrophobic C18 and strong anion exchange retention mechanisms using a mass spectrometer compatible volatile mobile phase consisting of trifluoroacetic acid and acetonitrile while gradient elution was applied. The method was validated following the ICH guideline Q2(R1) and found suitable for the assessment of ibandronate's related substances. The observed CAD-response for all identified impurities was linear (R(2)>0.995) over a small concentration range (0.05-0.25) and a quantification limit of at least 0.03% was found. Four batches of two different manufacturers were tested by means of the method. None of the batches contained a single impurity above 0.05%. The major impurities of all batches were the synthesis by-products N-desmethyl- and N-despentyl ibandronate as well as N,N-dimethyl pamidronate. PMID:26092222

  5. Classification of commercial Catuaba samples by NMR, HPLC and chemometrics.

    PubMed

    Daolio, Cristina; Beltrame, Flávio L; Ferreira, Antonio G; Cass, Quezia B; Cortez, Diógenes Aparício Garcia; Ferreira, Márcia M C

    2008-01-01

    For over a century, Catuaba has been used in Brazilian folk medicine as an aphrodisiac even though the identity of the plant material employed is often uncertain. The species recommended by the Brazilian Pharmacopeia is Anemopaegma arvense (Bignoniaceae), but many other plants, regionally known as Catuaba, are commercialised. Frequently, the quality control of such a complex system is based on chemical markers that do not supply a general idea of the system. With the advent of the metabolomics approach, a global analysis of samples becomes possible. It appears that (1)H-NMR is the most useful method for such application, since it can be used as a wide-spectrum chemical analysis technique. Unfortunately, the generated spectra is complex so a possible approach is to look at the metabolite profile as a whole using multivariate methods, for example, by application of principal component analysis (PCA). In the present paper, we describe for the first time a proton high-resolution magic angle spinning nuclear magnetic resonance ((1)H-HR-MAS NMR) method coupled with PCA for the metabolomic analysis of some commercial Catuaba samples, which provided a reduction in the time required for such analysis. A comparative study of HPLC, HR-MAS and liquid-NMR techniques is also reported. PMID:17890569

  6. Quantification of Free Carnitine and Acylcarnitines in Plasma or Serum Using HPLC/MS/MS.

    PubMed

    Scott, David; Heese, Bryce; Garg, Uttam

    2016-01-01

    Acylcarnitines are formed by esterification between fatty acids CoA or organic acids CoA molecules and carnitine. In various fatty acids oxidation defects and organic acidurias, there is increased concentration of corresponding acylcarnitines. Abnormalities in specific acylcarnitines are used in the diagnosis of fatty acids oxidation defects and organic acidurias. Most commonly used method for the assay of acylcarnitines is HPLC-tandem mass spectrometry (HPLC/MS/MS). A HPLC/MS/MS method is described for the quantification of number of acylcarnitines. The method involves butylation of carnitine/acylcarnitines using acidified butanol, HPLC flow injection, and measurement of acylcarnitines using precursor ion scan and multiple reactions monitoring (MRM). PMID:26602112

  7. 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.

  8. Spectroscopic characterization and quantitative determination of atorvastatin calcium impurities by novel HPLC method

    NASA Astrophysics Data System (ADS)

    Gupta, Lokesh Kumar

    2012-11-01

    Seven process related impurities were identified by LC-MS in the atorvastatin calcium drug substance. These impurities were identified by LC-MS. The structure of impurities was confirmed by modern spectroscopic techniques like 1H NMR and IR and physicochemical studies conducted by using synthesized authentic reference compounds. The synthesized reference samples of the impurity compounds were used for the quantitative HPLC determination. These impurities were detected by newly developed gradient, reverse phase high performance liquid chromatographic (HPLC) method. The system suitability of HPLC analysis established the validity of the separation. The analytical method was validated according to International Conference of Harmonization (ICH) with respect to specificity, precision, accuracy, linearity, robustness and stability of analytical solutions to demonstrate the power of newly developed HPLC method.

  9. Rapid HPLC-MS method for the simultaneous determination of tea catechins and folates.

    PubMed

    Araya-Farias, Monica; Gaudreau, Alain; Rozoy, Elodie; Bazinet, Laurent

    2014-05-14

    An effective and rapid HPLC-MS method for the simultaneous separation of the eight most abundant tea catechins, gallic acid, and caffeine was developed. These compounds were rapidly separated within 9 min by a linear gradient elution using a Zorbax SB-C18 packed with sub 2 μm particles. This methodology did not require preparative and semipreparative HPLC steps. In fact, diluted tea samples can be easily analyzed using HPLC-MS as described in this study. The use of mass spectrometry detection for quantification of catechins ensured a higher specificity of the method. The percent relative standard deviation was generally lower than 4 and 7% for most of the compounds tested in tea drinks and tea extracts, respectively. Furthermore, the method provided excellent resolution for folate determination alone or in combination with catechins. To date, no HPLC method able to discriminate catechins and folates in a quick analysis has been reported in the literature. PMID:24734959

  10. A rapid sample preparation method for the HPLC determination of the opioid antagonist naltrexone in serum.

    PubMed

    Hurst, W J; Zagon, I S; Aboul-Enein, H Y

    1999-08-01

    HPLC with UV and electrochemical detection has routinely been employed for the determination of the opioid antagonist naltrexone in serum. Sample preparation protocols range from liquid/liquid to solid phase extraction. The sample preparation described in this communication uses ultrafiltration as the mode of sample preparation prior to HPLC analysis. The method is accurate, precise and saves considerable time compared to previously published techniques. PMID:10483613

  11. Syntheses of the sulfoconjugated isomers of norepinephrine and dopamine, controlled by HPLC with ultraviolet detection.

    PubMed

    Strobel, G; Werle, E; Helfinger, H; Griebel, D; Weicker, H

    1988-09-15

    The physiological significance of sulfoconjugated catecholamines and their involvement in clinical disorders, e.g. hypertension and Parkinsonism, is poorly investigated. For this reason, the sulfoconjugated isomers of dopamine as well as of norepinephrine were synthesized by modified methods. All isomers and their intermediates could be detected by a reversed-phase high-performance liquid chromatography with ultraviolet detection (HPLC-UV) with short retention times and a good reproducibility. Ion-exchange chromatography with an extended column length improved the separation of the reaction products, and the immediate control by HPLC-UV enabled precise cutting of the fractions. The selection of the fractions with the optimum ratios of product/by-product resulted in improved yields and highest purity. All by-products, e.g. dopamine sulfonic acids, were less than 0.04%, as detected by HPLC-UV and, in addition, the contamination by free catecholamines was only 41 x 10(-4)-87 x 10(-4)%, as measured by HPLC with electrochemical detection (HPLC-ED). The purity was further demonstrated in two highly sensitive biological assays: cAMP production in human mononuclear leukocytes and aggregation of human platelets. The sulfoconjugated catecholamines were characterized by melting point, thin-layer chromatography, infrared spectrum, HPLC-UV, elemental analysis, and unequivocally identified by 1H-NMR. PMID:3416878

  12. HPLC-DAD protein kinase inhibitor analysis in human serum.

    PubMed

    Dziadosz, Marek; Lessig, Rüdiger; Bartels, Heidemarie

    2012-04-15

    We here describe an HPLC-DAD method to analyse different protein kinase inhibitors. Potential applications of this method are pharmacokinetic studies and therapeutic drug monitoring. Optimised chromatography conditions resulted in a very good separation of seven inhibitors (vatalanib, bosutinib, canertinib, tandutinib, pazopanib, dasatinib - internal standard and erlotinib). The good sensitivity makes this method competitive with LC/MS/MS. The separation was performed with a Lichrospher 100-5 RP8, 250 mm × 4 mm column maintained at 30 ± 1 °C, and with a mobile phase of 0.05 M H(3)PO(4)/KH(2)PO(4) (pH=2.3)-acetonitrile (7:3, v/v) at a flow rate of 0.7 mL/min. A simple and fast sample preparation sequence with liquid-liquid extraction led to good recoveries (73-90%) of all analytes. The recovery hardly reached 50% only for pazopanib. This method can also be used for targeted protein kinase inhibitor quantification. A perfect linearity in the validated range (20-10,000 ng/mL) and an LOQ of 20 ng/mL were achieved. The relative standard deviations and accuracies of all examined drug concentrations gave values much lower than 15% both for between- and within-batch calculations. All analysed PKIs were stable for 6 months in a 1mg/mL dimethyl sulfoxide stock solution. Vatalanib, bosutinib and erlotinib were also stable in human serum in the whole examined concentration range. PMID:22425385

  13. Identifying Phytoplankton Classes In California Reservoirs Using HPLC Pigment Analysis

    NASA Astrophysics Data System (ADS)

    Siddiqui, S.; Peacock, M. B.; Kudela, R. M.; Negrey, K.

    2014-12-01

    Few bodies of water are routinely monitored for phytoplankton composition due to monetary and time constraints, especially the less accessible bodies of water in central and southern California. These lakes and estuaries are important for economic reasons such as tourism and fishing. This project investigated the composition of phytoplankton present using pigment analysis to identify dominant phytoplankton groups. A total of 28 different sites with a wide range of salinity (0 - 60) in central and southern California were examined. These included 13 different bodies of water in central California: 6 in the Sierras, 7 in the San Francisco Bay Estuary, and 15 from southern California. The samples were analyzed using high-performance liquid-chromatography (HPLC) to quantify the pigments present (using retention time and the spectral thumbprint). Diagnostic pigments were used to indicate the phytoplankton class composition, focusing on diatoms, dinoflagellates, cryptophytes, and cyanobacteria - all key phytoplankton groups indicative of the health of the sampled reservoir. Our results indicated that cyanobacteria dominated four of the seven bodies of central California water (Mono Lake, Bridgeport Reservoir, Steamboat Slough, and Pinto Lake); cryptophytes and nannoflagellates dominated two of the central California bodies of water (Mare Island Strait and Topaz Lake); and diatoms and dinoflagellates dominated one central California body of water, Oakland Inner Harbor, comprising more than 70% of the phytoplankton present. We expect the bodies of water from Southern California to be as disparate. Though this data is only a snapshot, it has significant implications in comparing different ecosystems across California, and it has the potential to provide valuable insight into the composition of phytoplankton communities.

  14. Combined HPLC-CUPRAC (cupric ion reducing antioxidant capacity) assay of parsley, celery leaves, and nettle.

    PubMed

    Yildiz, Leyla; Başkan, Kevser Sözgen; Tütem, Esma; Apak, Reşat

    2008-10-19

    This study aims to identify the essential antioxidant compounds present in parsley (Petroselinum sativum) and celery (Apium graveolens) leaves belonging to the Umbelliferae (Apiaceae) family, and in stinging nettle (Urtica dioica) belonging to Urticaceae family, to measure the total antioxidant capacity (TAC) of these compounds with CUPRAC (cupric ion reducing antioxidant capacity) and ABTS spectrophotometric methods, and to correlate the TAC with high performance liquid chromatography (HPLC) findings. The CUPRAC spectrophotometric method of TAC assay using copper(II)-neocuproine (2,9-dimethyl-1,10-phenanthroline) as the chromogenic oxidant was developed in our laboratories. The individual antioxidant constituents of plant extracts were identified and quantified by HPLC on a C18 column using a modified mobile phase of gradient elution comprised of MeOH-0.2% o-phosphoric acid and UV detection for polyphenols at 280 nm. The TAC values of HPLC-quantified antioxidant constituents were found, and compared for the first time with those found by CUPRAC. The TAC of HPLC-quantified compounds accounted for a relatively high percentage of the observed CUPRAC capacities of plant extracts, namely 81% of nettle, 60-77% of parsley (in different hydrolyzates of extract and solid sample), and 41-57% of celery leaves (in different hydrolyzates). The CUPRAC total capacities of the 70% MeOH extracts of studied plants (in the units of mmol trolox g(-1)plant) were in the order: celery leaves>nettle>parsley. The TAC calculated with the aid of HPLC-spectrophotometry did not compensate for 100% of the CUPRAC total capacities, because all flavonoid glycosides subjected to hydrolysis were either not detectable with HPLC, or not converted to the corresponding aglycons (i.e., easily detectable and quantifiable with HPLC) during the hydrolysis step. PMID:18804638

  15. Separation and sensitive assay of THC in biological fluids by HPLC and GLC.

    PubMed

    Garrett, E R; Hunt, C A

    1976-05-01

    HPLC systems were developed to permit quantitative separation of delta9-tetrahydrocannabinol from many of the heptane extractable lipoidal and other endogenous substances in biological fluids. These substances interfered with the quantification by flame ionization GLC of unmodified compound and by electron capture GLC of pentafluorobenzoylated compound. Reverse phase HPLC elution, with 47% acetonitrile in water, and normal phase HPLC with 25% chloroform in heptane, separated tetrahydrocannabinol from 11-hydroxy-delta9-tetrahydrocannabinol and other monohydroxylated tetrahydrocannabinols. These systems also purified stock solutions of tetrahydrocannabinol from accompanying contaminants. The various monohydroxylated tetrahydrocannabinols were resolved from each other in normal phase, 80% chloroform in heptane. The delta8 and delta9-tetrahydrocannabinols were separable in normal phase with 5% tetrahydrofuran in hexane. The GLC analysis of pentafluorobenzoylated tetrahydrocannabinol had a sensitivity of 1 ng/ml of plasma with an estimated 5% standard error of an assay with the extraction and GLC procedures given herein. Radiochemical analysis of the HPLC separated fraction had s sensitivity of 0.2 ng/ml of plasma with an estimated 2% standard error of an assay. There was no significant difference between the liquid scintillation and electron capture GLC assays of the HPLC separated delta9-tetrahydrocannabinol obtained from the plasma of dogs administered the drug. Radiolabelled compounds can be added to plasma samples as internal standards to determine the recovery efficiencies of the several procedures in the analysis of unlabelled tetrahydrocannabinol. PMID:967239

  16. Improved method for HPLC analysis of polyamines, agmatine and aromatic monoamines in plant tissue

    NASA Technical Reports Server (NTRS)

    Slocum, R. D.; Flores, H. E.; Galston, A. W.; Weinstein, L. H.

    1989-01-01

    The high performance liquid chromatographic (HPLC) method of Flores and Galston (1982 Plant Physiol 69: 701) for the separation and quantitation of benzoylated polyamines in plant tissues has been widely adopted by other workers. However, due to previously unrecognized problems associated with the derivatization of agmatine, this important intermediate in plant polyamine metabolism cannot be quantitated using this method. Also, two polyamines, putrescine and diaminopropane, also are not well resolved using this method. A simple modification of the original HPLC procedure greatly improves the separation and quantitation of these amines, and further allows the simulation analysis of phenethylamine and tyramine, which are major monoamine constituents of tobacco and other plant tissues. We have used this modified HPLC method to characterize amine titers in suspension cultured carrot (Daucas carota L.) cells and tobacco (Nicotiana tabacum L.) leaf tissues.

  17. Monitoring of monosaccharides, oligosaccharides, ethanol and glycerol during wort fermentation by biosensors, HPLC and spectrophotometry.

    PubMed

    Monošík, Rastislav; Magdolen, Peter; Stredanský, Miroslav; Šturdík, Ernest

    2013-05-01

    The aim of the present study was to analyze sugar levels (namely maltose, maltotriose, glucose and fructose) and alcohols (ethanol and glycerol) during the fermentation process in wort samples by amperometric enzymatic biosensors developed by our research group for industrial application, HPLC and spectrophotometry, and to compare the suitability of the presented methods for determination of individual analytes. We can conclude that for the specific monitoring of maltose or maltotriose only the HPLC method was suitable. On the other hand, biosensors and spectrophotometry reflected a decrease in total sugar concentration better and were able to detect both glucose and fructose in the later stages of fermentation, while HPLC was not. This can be attributed to the low detection limits and good sensitivity of the proposed methods. For the ethanol and glycerol analysis all methods proved to be suitable. However, concerning the cost expenses and time analysis, biosensors represented the best option. PMID:23265480

  18. An RP-HPLC determination of 5-hydroxymethylfurfural in honey The case of strawberry tree honey.

    PubMed

    Spano, Nadia; Casula, Lucia; Panzanelli, Angelo; Pilo, Maria I; Piu, Paola C; Scanu, Roberta; Tapparo, Andrea; Sanna, Gavino

    2006-02-15

    The use of the RP-HPLC official method of the International Honey Commission (IHC) for the determination of 5-hydroxymethylfurfural (HMF) in strawberry tree honey (Arbutus unedo, a typical Sardinian honey) has brought to light a specific and heavy chromatographic interference that prevents accurate quantification. The interference has been identified as homogentisic acid (HA), i.e. the marker of the botanical origin of the honey. For this reason, an alternative RP-HPLC method is proposed. The bias-free method allows a complete separation of HMF from HA to the baseline level and is faster and more precise than the RP-HPLC official method: the detection and quantification limits are 1.9 and 4.0mgkg(-1), respectively, whereas the repeatability is ca. 2% in the HMF concentration range of 5-140mgkg(-1). PMID:18970477

  19. Determination of iodate by HPLC-UV after on-line electrochemical reduction to iodide.

    PubMed

    Wang, Tao; Lin, Weimei; Dai, Xueliang; Gao, Lijun; Wang, Bing; Quan, Dongqin

    2015-02-01

    In this study, a novel on-line pre-column electrochemical instrument (PECI) coupled with high-performance liquid chromatography (HPLC) was developed, and a novel method based on PEC-HPLC-UV for amplifying the ultraviolet (UV) response of iodate (IO₃⁻) was studied. Iodate undergoes reduction in the PECI, and the resulting I(-) was injected to an HPLC system and detected by a UV detector. For IO₃⁻ analysis, conditions that can influence the reduction efficiency, including applied potential, pH value and salt concentration, were investigated in detail. In an appropriate condition, the UV response of iodate after passing through PECI was almost 10 times more than that of the initial form with good precision (relative standard deviation 2.0-4.3%). The detection limit and quantity limit were 9 and 20 ng, respectively. It can be concluded that the proposed method is simple and highly sensitive. PMID:25002682

  20. A Chromatographic Determination of Aripiprazole using HPLC and UPLC: A Comparative Validation Study.

    PubMed

    Thakkar, R S; Saravaia, H T; Ambasana, M A; Kaila, H O; Shah, A K

    2011-07-01

    A simple, precise, and accurate isocratic reversed-phase (RP) stability-indicating HPLC assay method was developed and validated for determination of Aripiprazole in bulk and solid pharmaceutical dosage form. A reversed-phase C8 (250×4.0 mm, 5 μm particle size) column for HPLC and C8 (50×2.1mm, 1.7 μm particle size) for UPLC method in isocratic mode was used. The mobile phase consists of acetonitrile: 20 mM ammonium acetate (90:10, v/v), flow rate was set at 1.0 ml/min and 0.250 ml/min for HPLC and UPLC, respectively and the detection was performed for both methods were at 240 nm. Further the validation of both developed method was performed and subsequently compared to prove its better applicability. PMID:22707830

  1. A Chromatographic Determination of Aripiprazole using HPLC and UPLC: A Comparative Validation Study

    PubMed Central

    Thakkar, R. S.; Saravaia, H. T.; Ambasana, M. A.; Kaila, H. O.; Shah, A. K.

    2011-01-01

    A simple, precise, and accurate isocratic reversed-phase (RP) stability-indicating HPLC assay method was developed and validated for determination of Aripiprazole in bulk and solid pharmaceutical dosage form. A reversed-phase C8 (250×4.0 mm, 5 μm particle size) column for HPLC and C8 (50×2.1mm, 1.7 μm particle size) for UPLC method in isocratic mode was used. The mobile phase consists of acetonitrile: 20 mM ammonium acetate (90:10, v/v), flow rate was set at 1.0 ml/min and 0.250 ml/min for HPLC and UPLC, respectively and the detection was performed for both methods were at 240 nm. Further the validation of both developed method was performed and subsequently compared to prove its better applicability. PMID:22707830

  2. Chemical fingerprint analysis for quality control and identification of Ziyang green tea by HPLC.

    PubMed

    He, Xiaoye; Li, Jianke; Zhao, Wei; Liu, Run; Zhang, Lin; Kong, Xianghong

    2015-03-15

    A simple and reliable HPLC fingerprint method was developed and validated for the quality control and identification of Ziyang green tea. Ten batches of Ziyang green tea collected from different plantations in Shaanxi Ziyang of China were used to establish the fingerprint. The feasibility and advantages of the used HPLC fingerprint were verified for its similarity evaluation by systematically comparing chromatograms with professional analytical software recommended by State Food and Drug Administration (SFDA) of China. The similarities of the fingerprints of 10 batches of tea samples were all more than 0.981. Additionally, simultaneous quantification of 10 major bioactive ingredients in the tea samples was conducted to interpret the consistency of the quality test. The results indicated that the HPLC fingerprint as a characteristic distinguishing method combining similarity evaluation and quantification analysis can be successfully used to assess the quality and to identify the authenticity of Ziyang green tea. PMID:25308687

  3. 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

  4. Identification of ginsenosides in roots of Panax ginseng by HPLC-APCI/MS.

    PubMed

    Ma, Xiao-Qiong; Liang, Xin-Miao; Xu, Qing; Zhang, Xiao-Zhe; Xiao, Hong-Bin

    2005-01-01

    A new HPLC-APCI/MS method for the identification of ginsenosides has been developed. The analyses were performed on a reversed-phase C18 column using a binary eluent (acetonitrile and water) under gradient conditions. Although APCI is a high-temperature evaporative process, HPLC-APCI/MS could effectively identify thermo-labile ginsenosides. The [M-H]- ions and the thermal degradation ions of ginsenosides could be clearly observed under negative and positive ion conditions, respectively, and these were used to identify the molecular masses, the aglycone structures and the sugar groups of ginsenosides. APCI/MS can provide more explicit information than ESI/MS for identifying and distinguishing ginsenosides. Using the HPLC-APCI/MS method, 35 ginsenosides were identified in Panax ginseng. PMID:15997851

  5. Adulteration and cultivation region identification of American ginseng using HPLC coupled with multivariate analysis.

    PubMed

    Yu, Chunhao; Wang, Chong-Zhi; Zhou, Chun-Jie; Wang, Bin; Han, Lide; Zhang, Chun-Feng; Wu, Xiao-Hui; Yuan, Chun-Su

    2014-10-01

    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

  6. 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. PMID:22754056

  7. Comparison of piracetam measured with HPLC-DAD, HPLC-ESI-MS, DIP-APCI-MS, and a newly developed and optimized DIP-ESI-MS.

    PubMed

    Lenzen, Claudia; Winterfeld, Gottfried A; Schmitz, Oliver J

    2016-06-01

    The direct inlet probe-electrospray ionization (DIP-ESI) presented here was based on the direct inlet probe-atmospheric pressure chemical ionization (DIP-APCI) developed by our group. It was coupled to an ion trap mass spectrometer (MS) for the detection of more polar compounds such as degradation products from pharmaceuticals. First, the position of the ESI tip, the gas and solvent flow rates, as well as the gas temperature were optimized with the help of the statistic program Minitab® 17 and a caffeine standard. The ability to perform quantitative analyses was also tested by using different concentrations of caffeine and camphor. Calibration curves with a quadratic calibration regression of R (2) = 0.9997 and 0.9998 for caffeine and camphor, respectively, were obtained. The limit of detection of 2.5 and 1.7 ng per injection for caffeine and camphor were determined, respectively. Furthermore, a solution of piracetam was used to compare established analytical methods for this drug and its impurities such as HPLC-diode array detector (DAD) and HPLC-ESI-MS with the DIP-APCI and the developed DIP-ESI. With HPLC-DAD and 10 μg piracetam on column, no impurity could be detected. With HPLC-ESI-MS, two impurities (A and B) were identified with only 4.6 μg piracetam on column, while with DIP-ESI, an amount of 1.6 μg piracetam was sufficient. In the case of the DIP-ESI measurements, all detected impurities could be identified by MS/MS studies. Graphical Abstract Scheme of the DIP-ESI principle. PMID:27071761

  8. Pharmacokinetic study of arctigenin in rat plasma and organ tissue by RP-HPLC method.

    PubMed

    He, Fan; Dou, De-Qiang; Hou, Qiang; Sun, Yu; Kang, Ting-Guo

    2013-01-01

    A high-performance liquid chromatography (HPLC) technique was developed for the determination of arctigenin in plasma and various organs of rats after the oral administration of 30, 50 and 70 mgkg(-1) of arctigenin to the Sprague-Dawley rats. Results showed that the validated HPLC method was simple, fast, reproducible and suitable to the determination of arctigenin in rat plasma and organ tissue and one-compartmental model with zero-order absorption process can well describe the changes of arctigenin concentration in the plasma. The concentration of compound was highest in the spleen, less in the liver and the least in the lung. PMID:22404522

  9. A thin film degradation study of a fluorinated polyether liquid lubricant using an HPLC method

    NASA Technical Reports Server (NTRS)

    Morales, W.

    1986-01-01

    A High Pressure Liquid Chromatography (HPLC) separation method was developed to study and analyze a fluorinated polyether fluid which is promising liquid lubricant for future applications. This HPLC separation method was used in a preliminary study investigating the catalytic effect of various metal, metal alloy, and ceramic engineering materials on the degradation of this fluid in a dry air atmosphere at 345 C. Using a 440 C stainless steel as a reference catalytic material it was found that a titanium alloy and a chromium plated material degraded the fluorinated polyether fluid substantially more than the reference material.

  10. [Determination of saponosides from Panax ginseng C.A. Meyer. Comparison of official methods and HPLC].

    PubMed

    Guédon, D; Abbe, P; Cappelaere, N; Rames, N

    1989-01-01

    Official methods for determination of ginsenosides of the French and Helvetic Pharmacopoeias have been compared with HPLC method. Sample preparation schemes used are those of monographs with conventional solvent extraction and solid phase extraction with a polar and a non-polar sorbents, respectively kieselguhr and C 18 octadecyl. Liquid-solid sample clean-up with C 18 cartridge is the most effective procedure. Prior HPLC method, an hydrolysis step of malonylginsenosides is necessary. Very selective extraction resulting in highly purified solution authorizes reliable and rapid colorimetric determination from ginseng saponosides. PMID:2634933

  11. Multi-components determination by single reference standard and HPLC fingerprint analysis for Lamiophlomis rotata Pill.

    PubMed

    Chen, Jing; Wang, Yang; Sun, Guoxiang; Ma, Yongfu; Guo, Xingjie

    2016-07-01

    A validated HPLC method was developed to evaluate the quality of Lamiophlomis rotata Pill combining the multi-components analysis by single reference standard with HPLC fingerprint analysis. Five bioactive components (shanzhiside methyl ester, loganin, 8-O-acetylshanzhiside methyl ester, forsythoside B and luteolin-7-O-β-D-glucopyranoside) were selected as markers to control the quality of L. rotata Pill. The results revealed that the chromatographic fingerprint method coupled with multi-components analysis provides an effective and feasible way to determine the components in L. rotata Pill. PMID:26595778

  12. Solid-phase extraction and HPLC analysis of kebuzone and its metabolites in blood.

    PubMed

    Klimes, J; Sochor, J; Sedlacek, J

    1996-09-01

    A HPLC method for quantification of kebuzone and its metabolites in whole blood was developed. The compounds and the internal standard were isolated from blood by solid-phase extraction on a C-18 cartridge. A blood sample was to be hemolyzed before extraction. HPLC was performed on a C-18 column with the mobile phase composed of methanol/water acidified to pH 2.7 and UV absorbance detection at 247 nm. This method has been successfully applied to a pharmacokinetic study of kebuzone and its metabolites in rabbits. PMID:8878255

  13. Identification and quantification of components in extracts of Uncaria tomentosa by HPLC-ES/MS.

    PubMed

    Montoro, P; Carbone, V; Quiroz, J de Dioz Zuniga; De Simone, F; Pizza, C

    2004-01-01

    The two main classes of secondary metabolites, alkaloids and quinovic acid glycosides, of Uncaria tomentosa (Willd.) DC. (Rubiaceae), a Peruvian plant commonly known as 'uña de gato', have been analysed. Separation of the alkaloidal fraction was achieved using a solid phase extraction method based on cationic exchange, and an analytical method employing HPLC-ES/MS has been developed. Quantitative data for commercial wild bark, cultivated bark and leaves are reported. The analysis of quinovic acid glycosides was performed directly on the crude extract using both a fast analytical method based on flow injection ES/MS, and a more complete analytical technique using HPLC-MS. PMID:14979528

  14. Continuous-flow stereoselective organocatalyzed Diels-Alder reactions in a chiral catalytic "homemade" HPLC column.

    PubMed

    Chiroli, Valerio; Benaglia, Maurizio; Cozzi, Franco; Puglisi, Alessandra; Annunziata, Rita; Celentano, Giuseppe

    2013-07-19

    Continuous-flow organocatalyzed Diels-Alder reactions have been performed with excellent enantioselectivity for the first time in a chiral "homemade" HPLC column, packed with silica on which a MacMillan catalyst has been supported by a straightforward immobilization procedure. The versatility of the system was also proven by running with the same column continuous-flow stereoselective reactions with three different substrates, showing that the catalytic reactor may efficiently work in continuo for more than 150 h; the regeneration of the HPLC column was also demonstrated, allowing to further extend the activity of the reactor to more than 300 operating hours. PMID:23808663

  15. Screening and Analysis of the Potential Bioactive Components of Poria cocos (Schw.) Wolf by HPLC and HPLC-MS(n) with the Aid of Chemometrics.

    PubMed

    Wu, Ling-Fang; Wang, Kun-Feng; Mao, Xin; Liang, Wen-Yi; Chen, Wen-Jing; Li, Shi; Qi, Qi; Cui, Ya-Ping; Zhang, Lan-Zhen

    2016-01-01

    The aim of the present study was to establish a new method based on Similarity Analysis (SA), Cluster Analysis (CA) and Principal Component Analysis (PCA) to determine the quality of different samples of Poria cocos (Schw.) Wolf obtained from Yunnan, Hubei, Guizhou, Fujian, Henan, Guangxi, Anhui and Sichuan in China. For this purpose 15 samples from the different habitats were analyzed by HPLC-PAD and HPLC-MS(n). Twenty-three compounds were detected by HPLC-MS(n), of which twenty compounds were tentatively identified by comparing their retention times and mass spectrometry data with that of reference compounds and reviewing the literature. The characteristic fragmentations were summarized. 3-epi-Dehydrotumulosic acid (F13), 3-oxo-16α,25-dihydroxylanosta-7,9(11),24(31)-trien-21-oic acid (F4), 3-oxo-6,16α-dihydroxylanosta-7,9(11),24(31)-trien-21-oic acid (F7) and dehydropachymic acid (F15) were deemed to be suitable marker compounds to distinguish between samples of different quality according to CA and PCA. This study provides helpful chemical information for further anti-tumor activity and active mechanism research on P. cocos. The results proved that fingerprint combined with a chemometric approach is a simple, rapid and effective method for the quality discrimination of P. cocos. PMID:26901179

  16. HPLC and HPLC/MS/MS Studies on Stress, Accelerated and Intermediate Degradation Tests of Antivirally Active Tricyclic Analog of Acyclovir.

    PubMed

    Lesniewska, Monika A; Dereziński, Paweł; Klupczyńska, Agnieszka; Kokot, Zenon J; Ostrowski, Tomasz; Zeidler, Joanna; Muszalska, Izabela

    2015-01-01

    The degradation behavior of a tricyclic analog of acyclovir [6-(4-MeOPh)-TACV] was determined in accordance with International Conference on Harmonization guidelines for good clinical practice under different stress conditions (neutral hydrolysis, strong acid/base degradation, oxidative decomposition, photodegradation, and thermal degradation). Accelerated [40±2°C/75%±5% relative humidity (RH)] and intermediate (30±2°C/65%±5% RH) stability tests were also performed. For observation of the degradation of the tested compound the RP-HPLC was used, whereas for the analysis of its degradation products HPLC/MS/MS was used. Degradation of the tested substance allowed its classification as unstable in neutral environment, acidic/alkaline medium, and in the presence of oxidizing agent. The tested compound was also light sensitive and was classified as photolabile both in solution and in the solid phase. However, the observed photodegradation in the solid phase was at a much lower level than in the case of photodegradation in solution. The study showed that both air temperature and RH had no significant effect on the stability of the tested substance during storage for 1 month at 100°C (dry heat) as well as during accelerated and intermediate tests. Based on the HPLC/MS/MS analysis, it can be concluded that acyclovir was formed as a degradation product of 6-(4-MeOPh)-TACV. PMID:26525242

  17. Competitive Nitration of Benzene-Fluorobenzene and Benzene-Toluene Mixtures: Orientation and Reactivity Studies Using HPLC

    ERIC Educational Resources Information Center

    Blankespoor, Ronald L.; Hogendoorn, Stephanie; Pearson, Andrea

    2007-01-01

    The reactivity and orientation effects of a substituent are analyzed by using HPLC to determine the competitive nitration of the benzene-toluene and benzene-fluorobenzene mixtures. The results have shown that HPLC is an excellent instrumental method to use in analyzing these mixtures.

  18. Quantification of the molecular species of diacylglycerols,triacylglycerols and tetraacylglycerols in lesquerella (Physaria fendleri) oil by HPLC and MS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ten diacylglycerols (DAG), 74 triacylglycerols (TAG) and 13 tetraacylglycerols in the seed oil of Physaria fendleri were recently identified by HPLC and MS. These acylglycerols (AG) were quantified by HPLC with evaporative light scattering detector and electrospray ionization mass spectrometry of th...

  19. High performance liquid chromatography (HPLC): Water and environmental samples. (Latest citations from the EI compendex*plus database). Published Search

    SciTech Connect

    1996-01-01

    The bibliography contains citations concerning analyses of water by high pressure, high speed, high performance liquid chromatographic (HPLC). Environmental-related samples such as wastewaters, sewage sludge, and sediment are also covered. HPLC techniques are discussed and equipment such as detectors and columns is evaluated. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  20. 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. PMID:26353956

  1. IDENTIFICATION AND QUANTIFICATION OF THE MOLECULAR SPECIES OF ACYLGLYCEROLS IN CASTOR OIL BY HPLC USING ELSD

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sixteen molecular species of acylglycerols (AG) in castor oil have been identified and quantified using HPLC. ELSD (evaporative light scattering detection) responses of different amounts of the standards of molecular species of AG were nearly linear and similar. In general, the addition of a double ...

  2. Performance of HPLC/MS microchips in isocratic and gradient elution modes.

    PubMed

    Ehlert, Steffen; Trojer, Lukas; Vollmer, Martin; van de Goor, Tom; Tallarek, Ulrich

    2010-03-01

    We analyzed the chromatographic performance of particle-packed, all-polyimide high-performance liquid chromatography/mass spectrometry (HPLC/MS) microchips in terms of their hydraulic permeabilities and separation efficiency under isocratic and gradient elution conditions. The separation channels of the chips (with ca 50 microm x 75 microm trapezoidal cross-section and a length of 43 mm) were slurry packed with either 3.5 or 5 microm spherical porous C18-silica particles. A custom-built holder enveloped the chip during packing to prevent channel deformation and delamination from high pressures. It is shown that the packing conditions significantly impact the packing density of the HPLC/MS chips, which determines their performance in both, isocratic and gradient elution modes. Even with steep solvent gradients, peak shape and chromatographic resolution for the densely packed HPLC/MS chips are much improved. Our data show that the analytical power of the HPLC/MS chip is limited by the quality of the chromatographic separation. PMID:20209581

  3. Extraction and Purification of Glucoraphanin by Preparative High-Performance Liquid Chromatography (HPLC)

    ERIC Educational Resources Information Center

    Lee, Iris; Boyce, Mary C.

    2011-01-01

    A student activity that focuses on the isolation of glucoraphanin from broccoli using preparative high-performance liquid chromatography (HPLC) is presented here. Glucoraphanin is a glucosinolate, whose byproducts are known to possess anticancer properties. It is present naturally at high levels in broccoli and other "Brassica" vegetables. This…

  4. Using HPLC-Mass Spectrometry to Teach Proteomics Concepts with Problem-Based Techniques

    ERIC Educational Resources Information Center

    Short, Michael; Short, Anne; Vankempen, Rachel; Seymour, Michael; Burnatowska-Hledin, Maria

    2010-01-01

    Practical instruction of proteomics concepts was provided using high-performance liquid chromatography coupled with a mass selective detection system (HPLC-MS) for the analysis of simulated protein digests. The samples were prepared from selected dipeptides in order to facilitate the mass spectral identification. As part of the prelaboratory…

  5. HPLC and UPLC methods for the determination of zearalenone in noodles, cereal snacks and infant formula.

    PubMed

    Ok, Hyun Ee; Choi, Sung-Wook; Kim, Meehye; Chun, Hyang Sook

    2014-11-15

    High-performance liquid chromatography (HPLC) and ultra-performance liquid chromatography (UPLC) were compared to validate a method for determination of zearalenone (ZON) in noodles, cereal snacks, and infant formulas. The limits of detection and quantification in HPLC and UPLC were found to be 4.0 and 13.0 μg kg(-1) and 2.5 and 8.3 μg kg(-1), respectively. The average recoveries of ZON by HPLC and UPLC ranged from 79.1% to 105.3% and from 85.1% to 114.5%, respectively. The measurement uncertainties of the two methods for ZON determination were within the maximum standard uncertainty. The two methods showed that the levels of ZON in 163 naturally contaminated samples ranged from 4.3 to 8.3 μg kg(-1) by HPLC and 3.1 to 17.6 μg kg(-1) by UPLC. These findings indicate that either method is suitable for the determination of ZON in noodles, cereal snacks, and infant formulas, but UPLC gives faster results with better sensitivity. PMID:24912723

  6. A NEW HPLC METHOD FOR SEPARATION OF PHYTOPLANKTON PIGMENTS IN NATURAL SAMPLES

    EPA Science Inventory

    A new high-performance liquid chromatographic (HPLC) method was developed to analyze, in a single run, most polar and non-polar chlorophylls and carotenoids from marine phytoplankton. The method is based on a reverse-phase amide C16 (RP-amide C16) column and an elution gradient o...

  7. SEPARATION OF OCTYLPHENOL POLYETHER ALCOHOLS SURFACTANTS BY CAPILLARY COLUMN AND HPLC

    EPA Science Inventory

    Separation of nonionic octylphenol polyether alcohols (OPA) by supercritical fluid chromatography (SFC) and HPLC is described. sing a density programming and a 50-pm i.d. capillary column, a total of 18 group oligomers was separated. he effects of the operating parameters, such a...

  8. 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. PMID:23828911

  9. A SIMPLE HPLC METHOD FOR DETECTING CARBARYL AND 1-NAPHTHOL IN BIOLOGICAL TISSUES.

    EPA Science Inventory

    Carbamates are a class of pesticide used in both agricultural and residential applications. A simple HPLC method for detecting Carb and its metabolite 1-naphthol (Naph) in tissues was developed to try to correlate tissue levels of carbaryl (Carb) (a prototypical carbamate) with c...

  10. The Mysterious Death: An HPLC Lab Experiment. An Undergraduate Forensic Lab

    ERIC Educational Resources Information Center

    Beussman, Douglas J.

    2007-01-01

    A high-performance liquid chromatography (HPLC) laboratory experiment based on the separation of four prescription drugs (disopyramide, lidocaine, procainamide, and quinidine) is presented. The experiment is set within the forensic science context of the discovery of a patient's mysterious death where a drug overdose is suspected. Each lab group…

  11. Melanin determination by high performance liquid chromatography (HPLC) for K. marxianus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ultraviolet light (UV) mutated K. marxianus was found to turn dark brown during a growth assay. This brown color was hypothesized to be melanin overproduction influenced by the UV exposure. Cell cultures were oxidized and HPLC analyzed to determine melanin concentrations. The resulting melanin con...

  12. HPLC imprinted-stationary phase prepared by precipitation polymerisation for the determination of thiabendazole in fruit.

    PubMed

    Turiel, E; Tadeo, J L; Cormack, P A G; Martin-Esteban, A

    2005-12-01

    A molecularly imprinted polymer (MIP) tailored for the HPLC determination of the fungicide thiabendazole (TBZ) has been synthesised in one single preparative step by precipitation polymerisation in an acetonitrile/toluene co-solvent, using TBZ as template molecule, methacrylic acid as functional monomer and divinylbenzene-80 as crosslinker. The imprinted polymer particulates obtained were characterised by scanning electron microscopy and nitrogen sorption porosimetry. These analyses showed clearly that spherical polymer particulates (polymer microspheres) with narrow size distributions (average particle diameter approximately 3.5 microm) and well-developed pore structures had been produced. The imprinted microspheres were packed into a stainless steel HPLC column (50 x 4.6 mm id) and evaluated as an imprinted stationary phase. The imprinting effect was demonstrated clearly, i.e., the column was observed to bind TBZ selectively, and the effect of different chromatographic parameters (e.g., temperature, flow-rate and elution solvents) on TBZ retention/elution studied. Under optimised conditions, the TBZ-imprinted column was used for the HPLC-fluorescence (HPLC-F) determination of TBZ directly from orange (both whole fruit and juice), lemon, grape and strawberry extracts at low concentration levels in less than 15 min, without any need for a clean-up step in the analytical protocol. PMID:16284658

  13. Determination of Trace Level Triclosan in Water by Online Preconcentration and HPLC-UV Diode Array

    EPA Science Inventory

    An online high performance liquid chromatography (HPLC) method for the detection and quantification of trace levels of triclosan in water is discussed. Triclosan, an anti-bacterial agent, and related compounds have been shown to reach municipal waste waters through the disposal ...

  14. SEPARATION OF OCTYLPHENOL POLYETHER ALCOHOLS SURFACTANTS BY CAPILLARY COLUMN SFC AND HPLC

    EPA Science Inventory

    Separation of nonionic octylphenol polyether alcohols (OPA) by supercritical fluid chromatography (SFC) and HPLC is described. Using a density programming and a 50-μm i.d. capillary column, a total of 18 group oligomers was separated. The effects of the operating parameters, such...

  15. HPLC method to characterize cyanogen bromide collagen fractions containing pyridinoline groups.

    PubMed

    Bruno, R; Mazza, R; Calafiori, A R; Covello, C; Falbo, L; Martino, G; Marotta, M

    1997-01-01

    The HPLC method here described allows to separate CNBr collagen peptides within 2.5 h by reversed phase and gradient elution. The method is useful to determine both peptide bond and pyridinoline groups by absorbance spectophotometry. The fractions can be recovered and then submitted to other characterization techniques. PMID:10327703

  16. Analysis of acesulfame-K, saccharin and preservatives in beverages and jams by HPLC.

    PubMed

    Hannisdal, A

    1992-06-01

    A method is described that permits the simultaneous determination of acesulfame-K, saccharin and benzoic and sorbic acid in beverages and jams. The results of the HPLC analysis, using an RP-C 18 separation system with UV detection at 227 nm are reported. PMID:1496858

  17. Estimation of phytoplankton biomass using HPLC pigment analysis in the southwestern Black Sea

    NASA Astrophysics Data System (ADS)

    Ediger, D.; Soydemir, N.; Kideys, A. E.

    2006-08-01

    The phytoplankton population of the southwestern Black Sea in May 2001 was studied by taxonomic analysis using microscopic examination and by pigment analyses using high-performance liquid chromatography (HPLC). Pigment data, which identified phytoplankton assemblages dominated by dinoflagellates, diatoms and coccolithophores in May 2001, were compared to phytoplankton cell counts and biomass. There were significant ( p<0.002-0.01, r=0.56-0.67) relationships between the taxon-specific pigment concentrations and the taxon-specific cell numbers during this sampling period. The ratios of chlorophyll- a to the dominant accessory pigments calculated by multiple linear regressions were 1.2 (chlorophyll- a: peridinin) in dinoflagellates, 1.8 (chlorophyll- a: fucoxanthin) in diatoms, and 2.66 (chlorophyll- a: 19'-hexonoyloxyfucoxanthin) in coccolithophores. HPLC-determined chlorophyll- a biomass correlated well with the sum of the group-specific pigment biomass ( p<0.001, r2=0.95). The phytoplankton assemblage as revealed by the microscopic and HPLC analyses was thus made up of common Black Sea groups showing that HPLC pigment analysis can be used to quantify phytoplankton assemblages in the Black Sea based on simple ratios.

  18. Synthesis of safflomide and its HPLC measurement in mouse plasma after oral administration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    N-caffeoyltryptamine is a compound belonging to a group of phenylpropanoid amides found in plants. For this study, N-caffeoyltryptamine was chemically synthesized and a high performance liquid chromatography (HPLC) method was developed for quantifying N-caffeoyltryptamine in biological samples. The ...

  19. PHYTOPLANKTON PIGMENT ANALYSIS BY HPLC FOR ASSESSING COMMUNITY COMPOSITION IN THE LAURENTIAN GREAT LAKES

    EPA Science Inventory

    A technique to rapidly assess phytoplankton dynamics is being evaluated for its utility in the Great Lakes. Comparison to traditional microscopic techniques and to more recent in-situ FluoroProbe technology will allow us to determine if HPLC pigment analysis can provide unique a...

  20. Retention of [(18)F]fluoride on reversed phase HPLC columns.

    PubMed

    Ory, Dieter; Van den Brande, Jeroen; de Groot, Tjibbe; Serdons, Kim; Bex, Marva; Declercq, Lieven; Cleeren, Frederik; Ooms, Maarten; Van Laere, Koen; Verbruggen, Alfons; Bormans, Guy

    2015-01-01

    As [(18)F]fluoride is a starting reagent in the radiosynthesis of most fluorine-18 labeled positron emission tomography (PET) tracers, its chromatographic behavior on reversed phase (RP) HPLC columns is important for the purification performance and accuracy of RP HPLC quality control methods. We have investigated the chromatographic behavior and recovery of [(18)F]fluoride as a function of the type and brand of RP HPLC column, the pH and the composition of the mobile phase. Elution and elution profile of [(18)F]fluoride from six RP-HPLC columns (Waters XBridge C18 3 mm × 100 mm 3.5 μm; Grace Platinum EPS C18 4.6 mm × 100 mm, 3 μm; Waters XTerra C18 4.6 mm × 250 mm, 5 μm; Phenomenex C18 4.6 mm × 150 mm, 5 μm; Hamilton PRP-1 column 4.1 mm × 150 mm, 5 μm; Merck KGaA Chromolith Performance C18 3 mm × 100 mm) eluted with mobile phase composed of phosphate or acetate buffers (pH 2, 3, 4, 5, 7.3 and 9) and acetonitrile or ethanol as organic modifier were characterized. The elution profile was determined by on-line radioactivity measurement in the column eluate and recovery was calculated by comparison of radioactivity eluted with the HPLC column present or absent in the chromatographic flow path. Interestingly, [(18)F]fluoride recovery increased with increasing pH. At pH 3 all packed silica-based columns showed significant retention of fluorine-18, whereas almost no retention was observed on a polymeric PRP-1 column. However at pH 5, [(18)F]fluoride recovery was above 90% for each tested column. In addition, small differences were observed when changing the composition of the mobile phase. We therefore recommend to use a mobile phase with pH > 5 for silica based C18 columns for both quality control and semi-preparative HPLC of fluorine-18 labeled PET radiopharmaceuticals. If required a lower pH can be used in combination with a polymer based HPLC column. PMID:25898315

  1. Shape matters: size-exclusion HPLC for the study of nucleic acid structural polymorphism

    PubMed Central

    Largy, Eric; Mergny, Jean-Louis

    2014-01-01

    In recent years, an increasing number of reports have been focused on the structure and biological role of non-canonical nucleic acid secondary structures. Many of these studies involve the use of oligonucleotides that can often adopt a variety of structures depending on the experimental conditions, and hence change the outcome of an assay. The knowledge of the structure(s) formed by oligonucleotides is thus critical to correctly interpret the results, and gain insight into the biological role of these particular sequences. Herein we demonstrate that size-exclusion HPLC (SE-HPLC) is a simple yet surprisingly powerful tool to quickly and effortlessly assess the secondary structure(s) formed by oligonucleotides. For the first time, an extensive calibration and validation of the use of SE-HPLC to confidently detect the presence of different species displaying various structure and/or molecularity, involving >110 oligonucleotides forming a variety of secondary structures (antiparallel, parallel, A-tract bent and mismatched duplexes, triplexes, G-quadruplexes and i-motifs, RNA stem loops), is performed. Moreover, we introduce simple metrics that allow the use of SE-HPLC without the need for a tedious calibration work. We show that the remarkable versatility of the method allows to quickly establish the influence of a number of experimental parameters on nucleic acid structuration and to operate on a wide range of oligonucleotide concentrations. Case studies are provided to clearly illustrate the all-terrain capabilities of SE-HPLC for oligonucleotide secondary structure analysis. Finally, this manuscript features a number of important observations contributing to a better understanding of nucleic acid structural polymorphism. PMID:25143531

  2. Determination of cadmium and lead species and phytochelatins in pea (Pisum sativum) by HPLC-ICP-MS and HPLC-ESI-MSn.

    PubMed

    Barałkiewicz, Danuta; Kózka, Małgorzata; Piechalak, Aneta; Tomaszewska, Barbara; Sobczak, Paweł

    2009-07-15

    An analytical approach based on hyphenated techniques was used for studying the speciation of cadmium and lead in Pisum sativum. Proper preservation conditions were employed to avoid the oxidation of -SH groups and corresponding decomposition of metal-binding complexes. SEC column was washed with 5 mM beta-mercaptoethanol and then samples were analysed using ICP-MS as a detector. Results showed that cadmium is the inhibitor of lead uptake. HPLC-ESI-MS(n) assays revealed fragmentation pathways of phytochelatins. PMID:19559910

  3. [Estrogens determination of livestock dung based on UE-SPE-HPLC/FLD].

    PubMed

    Fu, Yin-Jie; Ling, Wan-Ting; Dong, Chang-Xun; Liu, Juan; Gao, Yan-Zheng; Pan, Yu-Lan

    2013-11-01

    A method for detecting the estrogens estriol, 17beta-estradiol, ethinyl estradiol, and bisphenol A in livestock dung was established by the combination of ultrasonic extraction (UE), solid phase extraction (SPE) purification, and high performance liquid chromatography (HPLC) with fluorescence detector (FLD). The dung samples were extracted with ethyl acetate ultrasonication for 30 min, and purified with C18 solid phase extraction column and related solvents. The test four estrogens in the dung samples were isolated with Inertsil ODS-SP-C18 reversed-phase columns (150 mm x 4.6 mm, 5 microm), and the isolated estrogens were detected with HPLC/FLD. The mobile phase of HPLC for the detection was methanol/acetonitrile/water (volume ratio of 20:30:50), with a flow rate of 0.8 mL x min(-1). The excitation and emission wavelengths of FLD were 280 and 310 nm, respectively, the HPLC column temperature was 40 degrees C, and the injection volume was 20 microL. Good linearity (correlation coefficient greater than 0.9995) was observed by the HPLC/FLD detection when the test four estrogens concentrations were in the range of 1.00-1000.00 microg x L(-1). The detection limit of estriol, bisphenol A, 17beta-estradiol, and ethinyl estradiol was 3.35, 5.01, 2.13, and 1.12 microg x kg(-1), respectively. When the added estrogens concentrations of pig, cow, and chicken dung samples were 0.05, 0.40, and, 1.00 microg x kg(-1), the average recovery of the four estrogens was 75.1%-91.1%, 78.4%-117.0%, and 78.6%-97.8%, respectively, with the relatively standard deviations (RSD, n = 6) all less than 6%. By adopting the established SPE-HPLC/FLD method to detect the estrogens in real pig, cow, and chicken dung samples from parts of the large-scale livestock raising farms in Nanjing of East China, the detection reproducibility was high, and the detection limit was low, being available and effective for the detection of the estrogens in livestock dung. PMID:24564161

  4. Phytochemical analysis of Rosa hybrida cv. 'Jardin de Granville' by HPTLC, HPLC-DAD and HPLC-ESI-HRMS: polyphenolic fingerprints of six plant organs.

    PubMed

    Riffault, Ludivine; Destandau, Emilie; Pasquier, Laure; André, Patrice; Elfakir, Claire

    2014-03-01

    The Rosa hybrida cultivar 'Jardin de Granville', a delicate clear pink flower, is here investigated through a progressive analytical strategy using complementary phytochemical screening methods in order to characterize the polyphenol content of several parts of the plant. The microwave hydro-ethanolic extract analysis of six different parts of the plant, carried out by High Performance Thin Layer Chromatography (HPTLC) and High Performance Liquid Chromatography coupled with a Diode Array Detector (HPLC-DAD) enabled initial identification of the polar molecular families present in each organ, namely tannins and flavonoids (quercetin and kaempferol derivatives). The HPLC fingerprints displayed different profiles for each organ, attesting to the original composition and potential valuation of the different plant parts. More detailed analyses of the extracts were then carried out by High Performance Liquid Chromatography coupled with electrospray ionization (ESI) mass spectrometry with a Q-TOF analyzer (ESI-HR-Q-TOF). Around 60 compounds were identified, mainly gallo-tannins, ellagi-tannins, catechin derivatives and glycoside derivatives of quercetin and kaempferol. Some compounds such as hyperoside or ellagic acid appeared to be ubiquitous and were found in abundance in each plant part. Woods were the richest organ in catechin and proanthocyanidin derivatives while kaempferol derivatives were more numerous and abundant in bud and flower parts. PMID:24461781

  5. HPLC-UV and HPLC-positive-ESI-MS analysis of the diterpenoid fraction from caper spurge (Euphorbia lathyris) seed oil.

    PubMed

    Bicchi, C; Appendino, G; Cordero, C; Rubiolo, P; Ortelli, D; Veuthey, J L

    2001-01-01

    Caper spurge (Euphorbia lathyris L.) seed oil contains a series of diterpenoids known as Euphorbia factors, or L-factors, L1-L9. They are esters of several polyols (lathyrol, epoxylathyrol, hydroxylathyrol and ingenol) and account for about 3-5% of the oil. The percentage of ingenol-based L-factors is very low, less than 5% of the diterpenoid fraction, but some of them (factors L5 and L6) are responsible for the irritant and co-carcinogenic activities of the oil. This paper reports an HPLC-UV and HPLC-positive-ESI-MS analysis of the diterpenoid fraction of caper spurge seed oil before and after selective hydrolysis of ingenol-based L-factors. Separation of lathyrane polyols and esters, and ingenol and its esters was achieved using a chromatographic system consisting of a C18 stationary phase and acetonitrile: water as mobile phase. A new macrocyclic constituent, the deoxy Euphorbia factor L1, was identified in the oil. PMID:11705332

  6. Measurement of methyl mercury (I) and mercury (II) in fish tissues and sediments by HPLC-ICPMS and HPLC-HGAAS.

    PubMed

    Jagtap, Rajani; Krikowa, Frank; Maher, William; Foster, Simon; Ellwood, Michael

    2011-07-15

    A procedure for the extraction and determination of methyl mercury and mercury (II) in fish muscle tissues and sediment samples is presented. The procedure involves extraction with 5% (v/v) 2-mercaptoethanol, separation and determination of mercury species by HPLC-ICPMS using a Perkin-Elmer 3 μm C8 (33 mm×3 mm) column and a mobile phase 3 containing 0.5% (v/v) 2-mercaptoethanol and 5% (v/v) CH(3)OH (pH 5.5) at a flow rate 1.5 ml min(-1) and a temperature of 25°C. Calibration curves for methyl mercury (I) and mercury (II) standards were linear in the range of 0-100 μgl(-1) (r(2)=0.9990 and r(2)=0.9995 respectively). The lowest measurable mercury was 0.4 μgl(-1) which corresponds to 0.01 μgg(-1) in fish tissues and sediments. Methyl mercury concentrations measured in biological certified reference materials, NRCC DORM - 2 Dogfish muscle (4.4±0.8 μgg(-1)), NRCC Dolt - 3 Dogfish liver (1.55±0.09 μgg(-1)), NIST RM 50 Albacore Tuna (0.89±0.08 μgg(-1)) and IRMM IMEP-20 Tuna fish (3.6±0.6 μgg(-1)) were in agreement with the certified value (4.47±0.32μgg(-1), 1.59±0.12 μgg(-1), 0.87±0.03 μgg(-1), 4.24±0.27 μgg(-1) respectively). For the sediment reference material ERM CC 580, a methyl mercury concentration of 0.070±0.002 μgg(-1) was measured which corresponds to an extraction efficiency of 92±3% of certified values (0.076±0.04 μgg(-1)) but within the range of published values (0.040-0.084 μgg(-1); mean±s.d.: 0.073±0.05 μgg(-1), n=40) for this material. The extraction procedure for the fish tissues was also compared against an enzymatic extraction using Protease type XIV that has been previously published and similar results were obtained. The use of HPLC-HGAAS with a Phenomenox 5 μm Luna C18 (250 mm×4.6 mm) column and a mobile phase containing 0.06 moll(-1) ammonium acetate (Merck Pty Limited, Australia) in 5% (v/v) methanol and 0.1% (w/v) l-cysteine at 25°C was evaluated as a complementary alternative to HPLC-ICPMS for the measurement of

  7. A stability-indicating HPLC method for medroxyprogesterone acetate in bulk drug and injection formulation.

    PubMed

    Burana-Osot, Jankana; Ungboriboonpisal, Sooksri; Sriphong, Lawan

    2006-03-18

    A stability-indicating HPLC assay method has been developed and validated for medroxyprogesterone acetate (MPA) in bulk drug and injectable suspension. An isocratic RP-HPLC was achieved on a Hichrom C(18) column (150 mm x 4.6mm i.d., 5 microm) utilizing a mobile phase of methanol 0.020 M acetate buffer pH 5 (65:35, v/v) and a photodiode array detector at 245 nm. The stress testing of MPA was carried out under acidic and alkaline hydrolysis, and oxidation conditions. MPA was well resolved from its degradation products, a main related substance (megestrol acetate) and two preservatives (methyl paraben and propyl paraben) with the resolution >or=2. The proposed method was validated for selectivity, linearity, accuracy, precision and solution stability. The method was found to be suitable for the quality control of MPA in bulk drug and injections as well as the stability-indicating studies. PMID:16242876

  8. Chemical fingerprinting of Equisetum arvense L. using HPTLC densitometry and HPLC.

    PubMed

    Gallo, Francesca R; Multari, Giuseppina; Federici, Elena; Palazzino, Giovanna; Giambenedetti, Massimo; Petitto, Valentina; Poli, Ferruccio; Nicoletti, Marcello

    2011-08-01

    Equisetum arvense L. is a herbaceous medicinal plant, commonly known as horsetail, whose extracts have been reported to possess diuretic and haemostatic properties. The aim of this study was to evaluate the use of fingerprint chromatographic methods on commercially available raw materials or preparations of E. arvense L. in order to ascertain their quality and identify possible adulterants using HPLC and HPTLC densitometry. Two chromatographic methods were used to determine the chemical fingerprints of E. arvense and other allied species. The first was based on HPTLC identification followed by densitometric measurement at 350 nm. The second was based on HPLC separation. The ease of sample preparation and the possibility of simultaneous analysis of several samples in a short time make HPTLC a method of choice for the comprehensive quality evaluation of herbal products. PMID:21854173

  9. Quantification of phytochelatins in plants by reversed-phase HPLC-ESI-MS-MS.

    PubMed

    El-Zohri, M H A; Cabala, R; Frank, H

    2005-08-01

    An on-line HPLC-ESI-MS-MS method has been developed for determination of glutathione and phytochelatins (PC) in plant tissues. For sample pretreatment, dithiothreitol (DTT) must be added at the very beginning, as an anti-oxidant. Optimization of instrumental conditions i.e. composition of HPLC mobile phase, ionization efficiency of the electrospray interface, and MS-MS detection in the multiple ion-monitoring mode, are the central aspects of this work. A polystyrene-packed column was found to be superior to a standard silica-packed reversed-phase column. A concave quadratic gradient of ammonium formate buffer and acetonitrile was found to be optimum. The limits of quantitation were 0.2 micromol kg(-1) plant tissue for glutathione and PC. The method has been applied to analysis of tissue samples from Vicia faba grown in Cd-containing nutrient solutions. PMID:16001238

  10. The retention behavior of ginsenosides in HPLC and its application to quality assessment of Radix Ginseng.

    PubMed

    Hu, Ping; Luo, Guo-An; Wang, Qing; Zhao, Zhong-Zhen; Wang, Wan; Jiang, Zhi-Hong

    2008-10-01

    This study systematically investigated the retention behavior of seven neutral ginsenosides Rg(1), Re, Rf, Rb(1), Rb(2), Rc, Rd, and an acidic ginsenoside R(0), the major pharmacologically active components of Radix Ginseng with RP-HPLC. The effects of solvent, pH value, ionic strength of the mobile phase, and column temperature were investigated using an octadecylsiloxane-bonded silica gel column. Based on the ginsenosides' retention characteristics, the concentration of acetonitrile and the gradient of the mobile phase needed to maintain the baseline separation of the major neutral ginsenosides in Radix Ginseng were theoretically predicted. Furthermore, the ionic strength of mobile-phase necessary to achieve good resolution of the neutral ginsenosides and acidic ginsenosides was carefully investigated. According to the results of the quantitative analysis of ginsenosides in eight batches of ginseng samples from different sources, the developed HPLC technique may be a valuable tool for the quality assessment of Radix Ginseng. PMID:18958416

  11. The retention behavior of ginsenosides in HPLC and its application to quality assessment of Radix Ginseng.

    PubMed

    Hu, Ping; Luo, Guo-An; Wang, Qing; Zhao, Zhong-Zhen; Wang, Wan; Jiang, Zhi-Hong

    2009-05-01

    This study systematically investigated the retention behavior of seven neutral ginsenosides Rg(1), Re, Rf, Rb(1), Rb(2), Rc, Rd, and an acidic ginsenoside R(0), the major pharmacologically active components of Radix Ginseng with RP-HPLC. The effects of solvent, pH value, ionic strength of the mobile phase, and column temperature were investigated using an octadecylsiloxane-bonded silica gel column. Based on the ginsenosides' retention characteristics, the concentration of acetonitrile and the gradient of the mobile phase needed to maintain the baseline separation of the major neutral ginsenosides in Radix Ginseng were theoretically predicted. Furthermore, the ionic strength of mobile-phase necessary to achieve good resolution of the neutral ginsenosides and acidic ginsenosides was carefully investigated. According to the results of the quantitative analysis of ginsenosides in eight batches of ginseng samples from different sources, the developed HPLC technique may be a valuable tool for the quality assessment of Radix Ginseng. PMID:19471880

  12. Analysis of macamides in samples of Maca (Lepidium meyenii) by HPLC-UV-MS/MS.

    PubMed

    McCollom, Megan M; Villinski, Jacquelyn R; McPhail, Kerry L; Craker, Lyle E; Gafner, Stefan

    2005-01-01

    The macamides are a distinct class of secondary metabolites that have so far been found only in Lepidium meyenii Walp. (Maca). Using HPLC-UV-MS/MS, the main macamides have been identified as n-benzylhexadecanamide, n-benzyl-(9Z)-octadecenamide, n-benzyl-(9Z, 12Z)-octadecadienamide, n-benzyl-(9Z, 12Z, 15Z)-octadecatrienamide and n-benzyloctadecanamide. The identities of n-benzyl-(9Z)-octadecenamide and n-benzyl-(9Z, 12Z)-octadecadienamide were confirmed by comparison of chromatographic and spectral properties with synthetic analogues. Total macamides have been quantified by HPLC-UV in plant material from different vendors using n-benzylhexadecanamide as an external standard. The amount of macamides in the dried plant material ranged from 0.0016 to 0.0123%. PMID:16315492

  13. Identification of pollutants in ammunition hazardous waste sites by thermospray HPLC/MS

    NASA Astrophysics Data System (ADS)

    Astratov, Michael; Prei[Beta], Alfred; Levsen, Karsten; Wunsch, Gerold

    1997-11-01

    HPLC/MS using thermospray ionization (TSP) was applied to identify and quantify explosives and other pollutants in groundwater samples of an ammunition hazardous waste site, where mainly TNT (2,4,6-trinitrotoluene), RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) and hexyl (2,2',4,4',6,6'-hexanitrodiphenylamine) were produced during World War II. In this polluted groundwater 31 compounds were identified including nitramines and their by-products, TNT and partially nitrated toluenes, 1,3,5-trinitrobenzene and partially nitrated benzenes, aminonitrotoluenes and nitroanilines, hexyl, nitrophenols (including picric acid), nitrobenzoic acids and aminonitrobenzoic acids. HPLC/TSP-MS is well-suited for the identification of pollutants on hazardous waste sites, but less suitable for their quantification.

  14. 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. PMID:16316736

  15. [Peptides analysis in digested edible bird's nest by HPLC-MS].

    PubMed

    Liu, Lin; Li, Xiu-Le; Gao, Jian-Ping; Kong, Ying-Jun; Wang, Ming-Lin; Zhang, Gui-Feng; Su, Zhi-Guo

    2013-03-01

    Edible bird's nest contains lots of glycoproteins. The glycosylation inhomogeneity for glycoprotein often results in wide range of molecular weight and the difficulty for protein separation and charaterization. In this paper, proteins in the edible bird's nest were extracted using multiple extractions, and then digested by PNgase F and trypsin. The digest mixture was separated with HPLC, and peptides were identified based on MS/MS data searching. The results indicated that the extracted proteins were amount to 79.7% of total protein in the edible bird's nest. More than 20 species of peptides in the digested mixture were identified. The sequences of these peptides showed similarity with some proteins from Swiss-prot. The research indicated that deglycosylation, tryptic digestion coupled with HPLC-MS/MS is a proper strategy for characterization of proteins in the edible bird's nest. PMID:23724682

  16. Separation of mAbs molecular variants by analytical hydrophobic interaction chromatography HPLC: overview and applications

    PubMed Central

    Haverick, Mark; Mengisen, Selina; Shameem, Mohammed; Ambrogelly, Alexandre

    2014-01-01

    Hydrophobic interaction chromatography-high performance liquid chromatography (HIC-HPLC) is a powerful analytical method used for the separation of molecular variants of therapeutic proteins. The method has been employed for monitoring various post-translational modifications, including proteolytic fragments and domain misfolding in etanercept (Enbrel®); tryptophan oxidation, aspartic acid isomerization, the formation of cyclic imide, and α amidated carboxy terminus in recombinant therapeutic monoclonal antibodies; and carboxy terminal heterogeneity and serine fucosylation in Fc and Fab fragments. HIC-HPLC is also a powerful analytical technique for the analysis of antibody-drug conjugates. Most current analytical columns, methods, and applications are described, and critical method parameters and suitability for operation in regulated environment are discussed, in this review. PMID:24751784

  17. A rapid and efficient preparation of [123I]radiopharmaceuticals using a small HPLC (Rocket) column.

    PubMed

    Katsifis, Andrew; Papazian, Vahan; Jackson, Timothy; Loc'h, Christian

    2006-01-01

    A simplified method for the rapid and efficient preparation of [(123)I]radiopharmaceuticals is described. Three radiopharmaceuticals, [(123)I]beta-CIT, [(123)I]MIBG and [(123)I]clioquinol, were synthesised and purified as model compounds. The radiotracers were labelled with iodine-123 using electrophilic oxidative conditions and purified by a compact semi-preparative reverse phase column (C-18, 3 microm, 7 x 53 mm, Alltima Rocket, Alltech) using aqueous-ethanol as HPLC solvents that were directly used for radiopharmaceutical formulation. The radiochemical purity of the radioiodinated tracers as assessed by analytical HPLC was higher than 99% with specific activity higher than 3 GBq/nmol. The total preparation time of a radiotracer ranged from 40 to 60 min and, starting from 3.7 GBq of iodine-123, more than 2.5 GBq of formulated radiopharmaceuticals were available for clinical investigations. PMID:16129607

  18. Qualitative and quantitative HPLC/MS determination of proanthocyanidins in areca nut (Areca catechu).

    PubMed

    Wu, Qingli; Yang, Yonghong; Simon, James E

    2007-12-01

    Proanthocyanidins (PACs) in areca nut (Areca catechu L.) were analyzed by high-performance liquid chromatography (HPLC) combined with electrospray-ionization mass spectrometry (ESI-MS) and compared to grape seed extract. Under optimized conditions, the separated PACs were individually analyzed and identified on the basis of their [M+H]+ peaks. The PAC distribution in areca nut was found to be very similar to that in grape seed, but lacking any gallate conjugates. Based on reverse-phase HPLC separation, the PAC monomers (+)-catechin (CA, 1) and (-)-epicatechin (EC; 2) were successfully quantified by ESI-MS in the selected-ion-monitoring (SIM) mode, (-)-epigallocatechin (EGC; 3) being used as internal standard. Detailed quality and validation assays showed that the accuracy and repeatability (n = 8) were within 10% for each analyte. PMID:18081092

  19. Ultratraces of carotenes in tomato purées: HPLC-TLS study

    NASA Astrophysics Data System (ADS)

    Luterotti, S.; Marković, K.; Franko, M.; Bicanic, D.; Vahčić, N.; Doka, O.

    2003-01-01

    The present study was designed to provide information about (i) the profile of carotene pigments and (ii) trace quantities of lycopene and β-carotene left in tomato purées. The ultrasensitive method comprising HPLC and thermal lens spectrometric (TLS) detection enabled us to detect as low as 0.3 and 1.1 ng ml-1 lycopene and β-carotene in purée extracts, respectively. Total concentration of β-carotene and lycopene (varying from 3 to 170 ng g-1) in the examined tomato purées may serve as an indicator of the carotene-specific antioxidative capacity of these products. Although conventional spectrophotometry can be used to rapidly assess the quality of products derived from tomatoes, a highly sensitive and selective method such as HPLC-TLS is needed for reliable analyses of samples such as, for example, those subjected to inappropriate storage and/or handling.

  20. Fingerprint analysis of polysaccharides from different Ganoderma by HPLC combined with chemometrics methods.

    PubMed

    Sun, Xiaomei; Wang, Haohao; Han, Xiaofeng; Chen, Shangwei; Zhu, Song; Dai, Jun

    2014-12-19

    A fingerprint analysis method has been developed for characterization and discrimination of polysaccharides from different Ganoderma by high performance liquid chromatography (HPLC) coupled with chemometrics means. The polysaccharides were extracted under ultrasonic-assisted condition, and then partly hydrolyzed with trifluoroacetic acid. Monosaccharides and oligosaccharides in the hydrolyzates were subjected to pre-column derivatization with 1-phenyl-3-methyl-5-pyrazolone and HPLC analysis, which will generate unique fingerprint information related to chemical composition and structure of polysaccharides. The peak data were imported to professional software in order to obtain standard fingerprint profiles and evaluate similarity of different samples. Meanwhile, the data were further processed by hierarchical cluster analysis and principal component analysis. Polysaccharides from different parts or species of Ganoderma or polysaccharides from the same parts of Ganoderma but from different geographical regions or different strains could be differentiated clearly. This fingerprint analysis method can be applied to identification and quality control of different Ganoderma and their products. PMID:25263911

  1. Effect of oxotremorine, physostigmine, and scopolamine on brain acetylcholine synthesis: a study using HPLC

    SciTech Connect

    Bertrand, N.; Beley, A. )

    1990-11-01

    The synthesis rate of brain acetylcholine (ACh) was estimated in mice following i.v. administration of ({sup 3}H)choline (Ch). The measurements were performed 1 min after the tracer injection, using the ({sup 3}H)ACh/({sup 3}H)Ch specific radioactivity ratio as an index of ACh synthesis rate. Endogenous and labeled Ch and ACh were quantified using HPLC methodology. Oxotremorine and physostigmine (0.5 mg/kg, i.p.) increased the steady state concentration of brain ACh by + 130% and 84%, respectively and of Ch by + 60% (oxotremorine); they decreased ACh synthesis by 62 and 55%, respectively. By contrast, scopolamine (0.7 mg/kg, i.p.) decreased the cerebral content of Ch by - 26% and of ACh by - 23% without enhancing the synthesis of ACh. The results show the utility of HPLC methodology in the investigation of ACh turnover.

  2. Protein profile study of the cervical cancer using HPLC-LIF

    NASA Astrophysics Data System (ADS)

    Sujatha; Rai, Lavanya; Krishnanand, B. R.; Mahato, K. K.; Kartha, V. B.; C, Santhosh

    2006-02-01

    Optical methods and proteomics investigations are becoming promising approaches for early detection of many diseases, which remain clinically silent for long periods. We have used efficient High Performance Liquid Chromatography (HPLC) separation combined with highly sensitive laser induced fluorescence detection of proteins present in clinical samples for diagnostic applications in cervical cancer. The protein profile and the fluorescence of individual proteins were simultaneously recorded using our HPLC-LIF system. Protein profiles (Chromatogram) of serum from normal male and female volunteers with and without tobacco habits, and malignant serum samples were studied. Protein profiles were also recorded for lysates of exfoliated cells collected from Pap smear of normal and cancer patients. The protein profile patterns were subjected to Principal component Analysis. Discrimination of normal and malignant samples were achieved with very high sensitivity and specificity.

  3. HPLC analysis of blood-brain barrier penetration of 4-fluorodeprenyl.

    PubMed

    Pöstényi, Zita; Tekes, Kornélia; Tóth-Molnár, Edit; Kalász, Huba

    2015-01-01

    Validated HPLC analysis was developed in order to monitor the level of 4-fluorodeprenyl in rats. Male Wistar rats were intraperitoneally treated with 30 mg/kg of (-)-4-fluorodeprenyl. The rats were sacrificed after 5, 15, 30 and 60 min of treatment, and various tissues were isolated, such as serum, brain, CSF, liver, testis and lacrimal gland. Perchloric acid was given to aliquots, which were then homogenized, centrifuged and the supernatants were taken. The 4-fluorodeprenyl content was determined using reversed-phase HPLC, based on the comparison of the calibration line of the spiked samples. The level of 4-fluorodeprenyl was between 0.5 and 24 μg/g, showing maximum concentration in the brain and the liver after 5 min following its administration and in serum, CSF, testis, eyes and lacrimal gland after 15 min following its administration, while a relatively high concentration was found in the liver and the lacrimal gland. PMID:25459953

  4. Determination of kynurenic acid in rat cerebrospinal fluid by HPLC with fluorescence detection.

    PubMed

    Bao, Ye; Luchetti, David; Schaeffer, Eric; Cutrone, Jingfang

    2016-01-01

    A sensitive HPLC method using fluorescence detection was developed to determine kynurenic acid (KYNA) level in rat cerebrospinal fluid (CSF). The method development was accomplished by screening different columns, optimizing zinc acetate concentration and determining the optimal HPLC flow rate. This method allowed direct injection of the CSF samples onto an Xselect C18 column and KYNA levels were measured fluorometrically by forming a fluorescent complex with zinc acetate that was delivered post-column. The limit of quantitation was 0.2 n m with 30 μL injection, corresponding to 6 fmol (signal-to-noise ratio = 10). The improved sensitivity enabled the measurement of KYNA in naive and drug-treated rat CSF. PMID:25963282

  5. Analysis of the monosaccharide composition of fucoidan by precolumn derivation HPLC

    NASA Astrophysics Data System (ADS)

    Zhang, Jingjing; Zhang, Quanbin; Wang, Jing; Shi, Xuelian; Zhang, Zhongshan

    2009-09-01

    We developed an HPLC method for analysis of the monosaccharide composition of fucoidans. The fucoidan was hydrolyzed into monosaccharides with 2 mol/L trifluoroacetic acid. Using ribose as the internal standard, the monosaccharide derivatives, obtained with 1-Phenyl-3-methyl-5-pyrazolone (PMP), were separated by reverse-phase HPLC using a gradient elution process, and monitored by ultraviolet detection at 245 nm. In the concentration range of 0.1-2.0 mmol/L, the peak area of each monosaccharide had a good linear relationship with its concentration ( r 2>0.998). The average recoveries of mannose, rhamnose, glucuronic acid, glucose, galactose, xylose, and fucose were 86.2%, 95.1%, 62.5%, 102.0%, 94.8%, 66.6%, and 105.1%, respectively. This method was accurate and had good reproducibility and could be used to determine the monosaccharide contents of fucoidans.

  6. 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. PMID:25038704

  7. Development of an HPLC post-column antioxidant assay for Solidago canadensis radical scavengers.

    PubMed

    Marksa, Mindaugas; Radušienė, Jolita; Jakštas, Valdas; Ivanauskas, Liudas; Marksienė, Rūta

    2016-01-01

    The aim of this work was to modify and validate the post-column high-performance liquid chromatography (HPLC)-ABTS and DPPH methods for evaluating the antioxidant activity of the methanolic extracts of Solidago canadensis (Canadian goldenrod) leaves and flowers. Separation of the analytes was performed via the HPLC-PDA method on a YMC analytical column using a gradient elution program. Three compounds with antioxidant properties - chlorogenic acid, rutin and isoquercitrin - and two unidentified antioxidants were established. The research showed that the coil temperature regimes and loop length combinations influence the optimised post-column assay method for detecting the antioxidant activity of goldenrod radical scavengers. Investigations established that the temperature in the reaction coil was a substantial factor contributing to the signal strength of the analytes after reacting with the DPPH and ABTS radicals. PMID:25835071

  8. Isolation, Identification, and Characterization of One Degradation Product in Ambroxol by HPLC-Hyphenated Techniques

    PubMed Central

    Thummala, Veera Raghava Raju; Ivaturi, Mrutyunjaya Rao; Nittala, Someswara Rao

    2014-01-01

    This study details the isolation, identification, and characterization of ambroxol’s unknown impurity. One unknown impurity of ambroxol was formed in the formulated drug under stress conditions [40°C /75% relative humidity (RH) for 6 months] with the relative retention time (RRT) 0.68 in RP-HPLC. The impurity was enriched by exposing it to heat and it was isolated by using preparative HPLC. The enriched impurity was purified and characterized using the following sophisticated techniques: 2D NMR (gDQ-COSY, gHSQC, and gHMBC), FTIR, and LC-MS/MS. On the basis of the spectral data, the impurity was characterized as trans-4-(6,8-dibromoquinazolin-3(4H)-yl)cyclohexanol. PMID:24959402

  9. Effective method for the detection of piroxicam in human plasma using HPLC.

    PubMed

    Calvo, Adriana Maria; Prado, Mariel Tavares de Oliveira; Dionísio, Thiago José; Marques, Maria Paula; Brozoski, Daniel Thomas; Lanchote, Vera Lúcia; Faria, Flávio Augusto Cardoso; Santos, Carlos Ferreira

    2016-05-20

    Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used by the general population to alleviate inflammation and pain after oral surgeries. Piroxicam is among the most commonly used NSAIDs and excels in controlling pain, swelling, trismus and other common symptoms of inflammation. This study aimed to evaluate different concentrations of piroxicam and its major metabolite, 5'-hydroxypiroxicam, in human plasma samples over time using high performance liquid chromatography (HPLC) after liquid-liquid extraction. Briefly, 10 volunteers participated in this study after approval by the Ethics Committee of Bauru School of Dentistry, Universidade de São Paulo - USP, Brazil. Volunteers received a single dose oral of piroxicam (20 mg) and had blood collected at various times following an established protocol. The methodology of liquid-liquid extraction was effective for determining concentrations of piroxicam in plasma using HPLC in 10 out of 10 volunteers while 5'-hydroxypiroxicam was only detected in 2 out of 10 volunteers. PMID:27223141

  10. [Determination of 7 bio-active alkaloids in Stephania plants by RP-HPLC].

    PubMed

    Huang, J; Guo, J; Duan, G

    1998-07-01

    Seven bio-active alkaloids (stepholidine, sinoacutine, isocorydine, l-tetrahydropalmatine, crebanine, fanchinoline and tetrandrine) in Stephania plants were determined by RP-HPLC, using UV detection (282 nm) and gradient elution. The reversed phase system consisted of ODS column and methanol-water-triethylamine as mobile phase. The flow rate was 1.0 ml.min-1. Good linearity between peak heights and concentrations of the alkaloids was obtained in the concentration range. The HPLC method proved accurate, precise and sensitive. The results showed that there were some differences in the occurrence and content of the alkaloids between various species and between the same species from different habitats and collecting time. Based on the results, some species with high content of the 7 bio-active alkaloids were selected. The study provided some useful information for the utilization of medicinal plant resources in the genus Stephania. PMID:12016887

  11. Chemical fingerprint and quantitative analysis for quality control of polyphenols extracted from pomegranate peel by HPLC.

    PubMed

    Li, Jianke; He, Xiaoye; Li, Mengying; Zhao, Wei; Liu, Liu; Kong, Xianghong

    2015-06-01

    A simple and efficient HPLC fingerprint method was developed and validated for quality control of the polyphenols extracted from pomegranate peel (PPPs). Ten batches of pomegranate collected from different orchards in Shaanxi Lintong of China were used to establish the fingerprint. For the fingerprint analysis, 15 characteristic peaks were selected to evaluate the similarities of 10 batches of the PPPs. The similarities of the PPPs samples were all more than 0.968, indicating that the samples from different areas of Lintong were consistent. Additionally, simultaneous quantification of eight monophenols (including gallic acid, punicalagin, catechin, chlorogenic acid, caffeic acid, epicatechin, rutin, and ellagic acid) in the PPPs was conducted to interpret the consistency of the quality test. The results demonstrated that the HPLC fingerprint as a characteristic distinguishing method combining similarity evaluation and quantitative analysis can be successfully used to assess the quality and to identify the authenticity of the PPPs. PMID:25624199

  12. Investigation of 4,5-epoxymorphinan degradation during analysis by HPLC.

    PubMed

    Quarry, Mary Ann; Sebastian, Dolores S; Diana, Frank

    2002-08-22

    Compounds of the 4,5-epoxymorphinan series have been shown to degrade in solution to the corresponding 2,2'-dimers when stored in amber glass HPLC vials. A colorant in the glass has been shown to catalyze the degradation. Although amber glass is routinely used to protect solutions from light degradation, it should not be used without evaluating its effect on sample stability. PMID:12151069

  13. Enantiomerization of Allylic Trifluoromethyl Sulfoxides Studied by HPLC Analysis and DFT Calculations.

    PubMed

    Bailly, Laetitia; Petit, Emilie; Maeno, Mayaka; Shibata, Norio; Trapp, Oliver; Cardinael, Pascal; Chataigner, Isabelle; Cahard, Dominique

    2016-02-01

    Enantiomerization of allylic trifluoromethyl sulfoxides occurs spontaneously at room temperature through the corresponding allylic trifluoromethanesulfenates via a [2,3]-sigmatropic rearrangement. Dynamic enantioselective high-performance liquid chromatography (HPLC) analysis revealed the stereodynamics of these sulfoxides ranging from chromatographic resolution to peak coalescence at temperatures between 5 and 53 °C. The rate constant of enantiomerization and activation parameters were determined and compared with Density Functional Theory (DFT) calculations. PMID:26689286

  14. Characterization of plasma protein binding dissociation with online SPE-HPLC

    PubMed Central

    Li, Ping; Fan, Yiran; Wang, Yunlong; Lu, Yaxin; Yin, Zheng

    2015-01-01

    A novel parameter of relative recovery (Rre) was defined and determined by online SPE-HPLC to characterize plasma protein binding (PPB) kinetics of highly plasma binding drugs. The proportional relationship of Rre with koff of PPB has been established with a new SPE model. A rapid, easy to use method could potentially be used to categorize PK properties of the drug candidates in the decision process of drug discovery and development. PMID:26460813

  15. Size-exclusion HPLC as a sensitive and calibrationless method for complex peptide mixtures quantification.

    PubMed

    Bodin, Alice; Framboisier, Xavier; Alonso, Dominique; Marc, Ivan; Kapel, Romain

    2015-12-01

    This work describes an original methodology to quantify complex peptide mixtures by size-exclusion high-performance liquid chromatography (SE-HPLC). The methodology was first tested on simulated elutions of peptide mixtures. For this set of experiments, a good estimation of the total peptide concentration was observed (error less than 10 %). Then 30 fractions obtained by ultrafiltration of hydrolysates from two different sources were titrated by Kjeldahl or BCA analysis and analysed by SE-HPLC for an experimental validation of the methodology. Very good matchs between methods were obtained. The linear working range depends on the hydrolysate but is generally between 0.2 and 4gL(-1) (i.e. between 10 and 200μg). Moreover, the presence of organic solvents or salts in samples does not impact the accuracy of the methodology contrary to common quantification methods. Hence, the findings of this study show that total concentration of complex peptide mixture can be efficiently determinate by the proposed methodology using simple SE-HPLC analysis. PMID:26523666

  16. HPLC fractions of human uremic plasma inhibit the RBC membrane calcium pump.

    PubMed

    Lindner, A; Vanholder, R; De Smet, R; Hinds, T R; Vogeleere, P; Sandra, P; Foxall, P; Ringoir, S

    1997-04-01

    We have reported that uremic plasma filtrates (UF) inhibit the red blood cell (RBC) membrane calcium pump. The inhibitor was dialyzable, smaller than 3,000 molecular weight, heat-stable, and protease-resistant. In the present study, we used reverse-phase preparative HPLC, analytical HPLC, and Sephadex G-25 elution to identify inhibitory fractions. Inhibition was confirmed in three different bioassays: (1) Sr2+ efflux in intact RBC, the primary bio-assay; (2) 45Ca efflux in intact RBC; and (3) calcium ATPase activity in isolated RBC membranes. Active fractions were analyzed by mass spectrometry, capillary electrophoresis, enzymatic analysis, gas chromatography-mass spectrometry, and nuclear magnetic resonance spectroscopy. These demonstrated a number of compounds, including: sugars, polyols, osmolytes like betaine and myoinositol, amino acids, and other metabolites, such as 3-D-hydroxybutyrate, dimethylglycine, trimethylamine-N-oxide, guanidinoacetic acid and glycine. Many individual compounds were then tested for an effect on the calcium pump. Thus, HPLC was able to separate a substantial number of compounds in inhibitory fractions. Efforts are under way for precise identification of the inhibitor, to advance our understanding of uremic toxicity and/or hypertension in CRF. PMID:9083269

  17. Direct injection analysis of fatty and resin acids in papermaking process waters by HPLC/MS.

    PubMed

    Valto, Piia; Knuutinen, Juha; Alén, Raimo

    2011-04-01

    A novel HPLC-atmospheric pressure chemical ionization/MS (HPLC-APCI/MS) method was developed for the rapid analysis of selected fatty and resin acids typically present in papermaking process waters. A mixture of palmitic, stearic, oleic, linolenic, and dehydroabietic acids was separated by a commercial HPLC column (a modified stationary C(18) phase) using gradient elution with methanol/0.15% formic acid (pH 2.5) as a mobile phase. The internal standard (myristic acid) method was used to calculate the correlation coefficients and in the quantitation of the results. In the thorough quality parameters measurement, a mixture of these model acids in aqueous media as well as in six different paper machine process waters was quantitatively determined. The measured quality parameters, such as selectivity, linearity, precision, and accuracy, clearly indicated that, compared with traditional gas chromatographic techniques, the simple method developed provided a faster chromatographic analysis with almost real-time monitoring of these acids. PMID:21360668

  18. [Establishment and application of HPLC-QAMS for quality evaluation of Chuanxiong Rhizoma].

    PubMed

    Qiao, Feng-xian; Cai, Hao; Tu, Peng-fei; Pei, Ke; Song, Xiao-qing

    2015-06-01

    A quantitative analysis method of multi-components with a single marker (QAMS) for simultaneous determination of six marker compounds (one from phenolic acids and five from phthalides) in Chuanxiong Rhizoma was established by applying HPLC and using butylidenephthalide as the internal reference substance. And also the feasibility and accuracy of the established method for quality evaluation and application of Chuanxiong Rhizoma were investigated and validated. The analysis was performed with the mobile phase consisting of acetonitrile - 0.2% aqueous formic acid. The flow rate was 1.0 mL . min-1 and the column temperature was maintained at 30 °C. The detection wavelengths were set at 252 nm (for ferulic acid, Z-ligustilide, and butylidenephthalide) and 266 nm (for senkyunolide I, senkyunolide A, and coniferyl ferulate), separately, and 20 µL was injected for analysis with gradient elution. The results showed that there were no significant differences observed between the HPLC-QAMS method and the external standard method (RSD <5%). The relative correction factors were credible (RSD < 5%) in changed chromatographic conditions. The established HPLC-QAMS method can be accurately used for simultaneously evaluating and controlling the quality of Chuanxiong Rhizoma with multi-components. PMID:26521448

  19. Simultaneous Speciation of Arsenic, Selenium, and Chromium by HPLC-ICP-MS

    USGS Publications Warehouse

    Wolf, Ruth E.; Morman, Suzette A.; Morrison, Jean M.; Lamothe, Paul J.

    2008-01-01

    An adaptation of an analytical method developed for chromium speciation has been utilized for the simultaneous determination of As(III), As(V), Se(IV), Se(VI), Cr(III), and Cr(VI) species using high performance liquid chromatography (HPLC) separation with ICP-MS detection. Reduction of interferences for the determination of As, Se, and Cr by ICP-MS is a major consideration for this method. Toward this end, a Dynamic Reaction Cell (DRC) ICP-MS system was used to detect the species eluted from the chromatographic column. A variety of reaction cell gases and conditions may be utilized, and the advantages and limitations of the gases tested to date will be presented and discussed. The separation and detection of the As, Se, and Cr species of interest can be achieved using the same chromatographic conditions in less than 2 minutes by complexing the Cr(III) with EDTA prior to injection on the HPLC column. Practical aspects of simultaneous speciation analysis will be presented and discussed, including issues with HPLC sample vial contamination, standard and sample contamination, species stability, and considerations regarding sample collection and preservation methods. The results of testing to determine the method's robustness to common concomitant element and anion effects will also be discussed. Finally, results will be presented using the method for the analysis of a variety of environmental and geological samples including waters, soil leachates and simulated bio-fluid leachates.

  20. Determination of Ephedra Alkaloids in Urine and Plasma by HPLC-UV: Collaborative Study

    PubMed Central

    Roman, Mark C.; Gray, D.; Laurensen, J.; Luo, G.; McClanahan, R.; Perez, R.; Roper, C.; Roscoe, V.; Shevchuk, C.; Suen, E.; Sullivan, D.

    2008-01-01

    Ten collaborating laboratories determined the ephedra alkaloid content (ephedrine, pseudoephedrine, norephedrine, norpseudoephedrine, methylephedrine, and methylpseudoephedrine) in 8 blind duplicates of human plasma and urine using high-performance liquid chromatography (HPLC) with UV detection. In addition to negative urine and plasma controls, urine samples were spiked with individual ephedra alkaloids ranging in concentration from about 1 to 5 μg/mL. Plasma samples were spiked with individual ephedra alkaloids ranging in concentration from about 100 to 400 ng/mL. Sample solutions were treated to solid-phase extraction using a strong-cation exchange column to help remove interferences. The HPLC analyses were performed on a polar-embedded phenyl column using UV detection at 210 nm. The ephedra alkaloids were not consistently detected in any of the spiked plasma samples. When ephedra alkaloids were detected in the plasma samples, reproducibility between blind replicate samples was very poor. Repeatability, reproducibility, and accuracy were also very poor for the spiked urine samples. On the basis of these re sults, the HPLC-UV method for the determination of ephedra alkaloids in human urine and plasma is not recommended for adoption as Official First Action. PMID:15084082

  1. 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. PMID:25572656

  2. Efficient IDUA Gene Mutation Detection with Combined Use of dHPLC and Dried Blood Samples

    PubMed Central

    Duarte, Ana Joana; Vieira, Luis

    2013-01-01

    Objectives. Development of a simple mutation directed method in order to allow lowering the cost of mutation testing using an easily obtainable biological material. Assessment of the feasibility of such method was tested using a GC-rich amplicon. Design and Methods. A method of denaturing high-performance liquid chromatography (dHPLC) was improved and implemented as a technique for the detection of variants in exon 9 of the IDUA gene. The optimized method was tested in 500 genomic DNA samples obtained from dried blood spots (DBS). Results. With this dHPLC approach it was possible to detect different variants, including the common p.Trp402Ter mutation in the IDUA gene. The high GC content did not interfere with the resolution and reliability of this technique, and discrimination of G-C transversions was also achieved. Conclusion. This PCR-based dHPLC method is proved to be a rapid, a sensitive, and an excellent option for screening numerous samples obtained from DBS. Furthermore, it resulted in the consistent detection of clearly distinguishable profiles of the common p.Trp402Ter IDUA mutation with an advantageous balance of cost and technical requirements. PMID:27335677

  3. The effects of eluent's optothermal parameters on TLS detection in gradient HPLC

    NASA Astrophysics Data System (ADS)

    Kožar Logar, J.; Franko, M.

    2003-01-01

    The effects of changing solvent composition on the limits of detection (LOD) of thermal lens spectroscopy (TLS) detection in gradient elution HPLC have been studied from the perspective of solvent's thermooptical properties. The refractive index and the temperature dependence of refractive index were measured and are reported for the first time for the methanol-acetone and methanol-ammonium acetate solutions used in this work, and some other methanol based chromatographic eluents. The TLS signal noise during a gradient HPLC protocol is increasing and its value reaches the maximum with a considerable time delay (up to 3 min) compared to the end point of the gradient protocol. The length of the chromatographic column was found to be an important parameter in reduction of signal noise resulting from incomplete solvent mixing. For some carotenoids the LOD values on the order of 50-100 pg/mL can be obtained on a 25 cm column with solvents that yield an increase in TLS enhancement factor up to 1.6 times during the gradient HPLC analysis.

  4. Quantitative analysis of eugenol in clove extract by a validated HPLC method.

    PubMed

    Yun, So-Mi; Lee, Myoung-Heon; Lee, Kwang-Jick; Ku, Hyun-Ok; Son, Seong-Wan; Joo, Yi-Seok

    2010-01-01

    Clove (Eugenia caryophyllata) is a well-known medicinal plant used for diarrhea, digestive disorders, or in antiseptics in Korea. Eugenol is the main active ingredient of clove and has been chosen as a marker compound for the chemical evaluation or QC of clove. This paper reports the development and validation of an HPLC-diode array detection (DAD) method for the determination of eugenol in clove. HPLC separation was accomplished on an XTerra RP18 column (250 x 4.6 mm id, 5 microm) with an isocratic mobile phase of 60% methanol and DAD at 280 nm. Calibration graphs were linear with very good correlation coefficients (r2 > 0.9999) from 12.5 to 1000 ng/mL. The LOD was 0.81 and the LOQ was 2.47 ng/mL. The method showed good intraday precision (%RSD 0.08-0.27%) and interday precision (%RSD 0.32-1.19%). The method was applied to the analysis of eugenol from clove cultivated in various countries (Indonesia, Singapore, and China). Quantitative analysis of the 15 clove samples showed that the content of eugenol varied significantly, ranging from 163 to 1049 ppb. The method of determination of eugenol by HPLC is accurate to evaluate the quality and safety assurance of clove, based on the results of this study. PMID:21313806

  5. Identification of a Panax ginseng fruit fingerprint by HPLC-ESI-MS.

    PubMed

    Zhao, H F; Xu, F F; Guo, Y T; Mi, H

    2016-01-01

    Over many years, parts of Panax ginseng (root and rhizome) have been identified and applied for medical purposes as traditional Chinese herbal medicine. Recently, research has indicated that ginseng fruit also contains similar compounds and is as rich as the other parts of the ginseng. This discovery may dramatically improve the efficient of outputs derived from ginseng products. Here, a new technique combining high-performance liquid chromatography (HPLC) with electrospray ionization tandem mass spectrometry (ESI-MS) was employed to identify the fingerprint of P. ginseng fruit. Using HPLC, compounds that are important for medical purposes were extracted and purified. Combined with ESI-MS, the characteristic peaks (nine common peaks) of those compounds were identified, and the accuracy was confirmed by analysis using the Chromatographic Fingerprint Similarity Evaluation System (2004A edition). Overall, 15 batches of ginseng fruit had a similarity of more than 0.80, 13 batches of samples had a similarity between 0.97 and 0.99, and two batches had a similarity less than 0.90. The test solution and mobile phase selection was discussed. The HPLC-ESI-MS method can produce repeatable and reliable results and can be applied in the quality control of P. ginseng fruit. PMID:26985953

  6. Stability-indicating HPLC method for the determination of darunavir ethanolate.

    PubMed

    Reddy, B V Rami; Jyothi, G; Reddy, B S; Raman, N V V S S; Reddy, K Subhash Chander; Rambabu, C

    2013-01-01

    A novel stability-indicating reversed-phase high-performance liquid chromatographic (HPLC) method has been developed for the quantitative determination of darunavir ethanolate, an HIV-1 protease inhibitor. The chromatographic separation was achieved using an X-Bridge C18 (150 × 4.6 mm × 3.5 µm) HPLC column in isocratic mode employing 0.01M ammonium formate (pH.3.0) buffer and acetonitrile in the ratio of 55:45 (v/v) with a flow rate of 1.0 mL/min. The detector wavelength was monitored at 265 nm and the column temperature was maintained at 30°C. Darunavir ethanolate was exposed to thermal, photolytic, acid, base and oxidative stress conditions. Considerable degradation of the drug substance was found to occur under acid, base and oxidative stress conditions. The peak homogeneity data of darunavir ethanolate obtained by photodiode array detection demonstrated the specificity of the method in the presence of degradants. The degradation products were well resolved from primary peak of darunavir, indicating that the method is specific and stability-indicating. The HPLC method was validated as per International Conference on Harmonization guidelines with respect to specificity, precision, linearity, accuracy and robustness. Regression analysis showed a correlation coefficient value greater than 0.999. The accuracy of the method was established based on the recovery obtained for darunavir ethanolate. PMID:23097581

  7. [Study on content determination of alkaloids and HPLC fingerprint of "Jianlian" Nelumbinis Plumula].

    PubMed

    Liu, Jiu-shi; He, Yan-feng; Gao, Shi-man; Zhang, Ben-gang; Liu, Hai-tao; Xiao, Pei-gen

    2015-08-01

    This study is to determine the content of three alkaloids and establish the HPLC fingerprint of "Jianlian" Nelumbinis Plumula. The HPLC method of content determination was as follows: Thermo C18 (4. 6 mm x 250 mm, 5 μm) was conducted with acetonitrile-sodium dodecyl sulfonate solution-acetic acid (56: 43: 1) at a flow rate of 1.0 mL x min(-1). The monitoring wavelength was set at 282 nm and the column temperature was 35 degrees C. The method of HPLC fingerprint was as follows: Agilent ZORBAX SB-Aq C18 (4.6 mm x 250 mm, 5 μm) was conducted with gradient elution of methanol and water at a flow rate of 0.8 mL x min(-1), the monitoring wavelength was set at 282 nm and the column temperature was 35 degrees C. Similarities evaluation and hierarchical clustering analysis were applied to demonstrate the variability of 12 batches of "Jianlian" Nelumbinis Plumula samples. The results demonstrated that 11 batches showed good similarity on chemical constituents. The method could well display the chemical information of "Jianlian" Nelumbinis Plumula. It was simple, reliable and could be used for the chemical quality control of "Jianlian" Nelumbinis Plumula. PMID:26790300

  8. Flow-Injection Preconcentration of Chloramphenicol Using Molecularly Imprinted Polymer for HPLC Determination in Environmental Samples

    PubMed Central

    Kowalski, Damian; Poboży, Ewa; Trojanowicz, Marek

    2011-01-01

    The residue of antibiotic chloramphenicol (CAP) is important issue for food quality control and also for the environmental monitoring. It is banned for use in food-producing animals and has very limited use in human medicine, because of its severe impact on human health. Determination of trace level of CAP in environmental samples requires a very sensitive analytical method and efficient preconcentration procedure. CAP can be efficiently preconcentrated in flow-injection system using flow-through reactor packed with molecularly imprinted polymer (MIP), but determination of CAP in eluate from MIP requires the application of chromatographic separation, which was made in reversed-phase HPLC system with UV detection. In optimized conditions the limit of detection for 100 mL sample in HPLC with offline preconcentration on MIP was evaluated as 0.66 mg/L. In hyphenated FIA-HPLC system with zone sampling the LOD for developed method was evaluated as 15 ng/L, which indicates the possibility of using it for analysis of environmental samples. PMID:21584273

  9. Screening for planar chlorobiphenyl congeners in marine biota by HPLC/PDA

    SciTech Connect

    Krahn, M.M.; Ylitalo, G.M.; Buzitis, J.; Sloan, C.A.; Boyd, D.T.; Chan, S.L.; Varanasi, U.

    1994-12-31

    A rapid method has been developed to screen for the dioxin-like planar chlorobiphenyl (CB) congeners, as well as certain other CBs and DDTs, in tissue samples from marine biota. Following extraction, the analytes were separated from interfering compounds on a gravity-flow column packed with acidic, basic and neutral silica gel. Subsequently, the planar CB congeners were resolved from the DDTs and other CBs by HPLC on Cosmosil PYE analytical columns cooled to 9 C and were measured by an ultraviolet (UV) photodiode array (PDA) detector. Individual analytes were identified by comparing their UV spectra and retention to those of reference standards and analyte purity was established by comparing spectra within a peak to the apex spectrum. The HPLC/PDA method was tested with tissue samples from fish, shellfish and marine mammals. Concentrations of the planar CB congeners, as well as certain other CBs and DDTs, in samples determined by screening compared favorably with those in the same samples analyzed by a comprehensive method. The screening method required about 20% of the time needed for the comprehensive analyses. The authors demonstrated the utility of the HPLC/PDA method by determining CBs and DDTs in edible tissue from a variety of seafood species; preliminary results from this survey will be presented.

  10. Comparative determination of sibutramine as an adulterant in natural slimming products by HPLC and HPTLC densitometry.

    PubMed

    Ariburnu, Etil; Uludag, Mehmet Fazli; Yalcinkaya, Huseyin; Yesilada, Erdem

    2012-05-01

    A new validated method for the identification and quantification of the sibutramine was developed by HPTLC-densitometry at 225 nm and advantages and disadvantages compared with HPLC-FLD at 225 nm emission and 316 nm excitation. Both methods were applied to the analysis of three natural slimming products in the market for the quantitative analysis of illegally added sibutramine. HPTLC separations were performed on (20 cm × 10 cm) glass HPTLC plates coated with silica gel 60 F(254) using a mobile phase, n-hexane-acetone-ammonia (10:1:0.1, v/v/v). For HPLC analysis, a phenyl column (5.0 μm, 150 mm × 4.6 mm, i.d.) and an isocratic mobile phase of acetonitrile-water-formic acid (pH 3.0; 0.19M) (45:55:0.78, v/v/v) was used. The calibration curve area versus concentration was found to be linear in the range of 250-2000 ng/spot(-1) and 5-200 μg/ml for HPTLC and HPLC, respectively. Both methods were validated for accuracy, precision, linearity, selectivity, recovery and short term stability. As a conclusion, these methods were found to be useful for the routine analysis of illegally added sibutramine in the marketed products. PMID:22410500

  11. Identification and quantitation of asparagine and citrulline using high-performance liquid chromatography (HPLC).

    PubMed

    Bai, Cheng; Reilly, Charles C; Wood, Bruce W

    2007-01-01

    High-performance liquid chromatography (HPLC) analysis was used for identification of two problematic ureides, asparagine and citrulline. We report here a technique that takes advantage of the predictable delay in retention time of the co-asparagine/citrulline peak to enable both qualitative and quantitative analysis of asparagine and citrulline using the Platinum EPS reverse-phase C18 column (Alltech Associates). Asparagine alone is eluted earlier than citrulline alone, but when both of them are present in biological samples they may co-elute. HPLC retention times for asparagine and citrulline were influenced by other ureides in the mixture. We found that at various asparagines and citrulline ratios [= 3:1, 1:1, and 1:3; corresponding to 75:25, 50:50, and 25:75 (microMol ml(-1)/microMol ml(-1))], the resulting peak exhibited different retention times. Adjustment of ureide ratios as internal standards enables peak identification and quantification. Both chemicals were quantified in xylem sap samples of pecan [Carya illinoinensis (Wangenh.) K. Koch] trees. Analysis revealed that tree nickel nutrition status affects relative concentrations of Urea Cycle intermediates, asparagine and citrulline, present in sap. Consequently, we concluded that the HPLC methods are presented to enable qualitative and quantitative analysis of these metabolically important ureides. PMID:19662174

  12. Development of an HPLC method for determination of pentachloronitrobenzene, hexachlorobenzene and their possible metabolites

    PubMed Central

    2011-01-01

    Background Pentachloronitrobenzene (PCNB) and hexachlorobenzene (HCB) are highly toxic and widespread in every environmental compartment. Some of metabolic products such as amino/nitro containing chlorinated aromatic compounds can be determined by gas chromatography coupled with electron capture detector (GC-ECD). However, it is difficult to identify some of chlorophenolic and chloroquinolic intermediates produced from PCNB and HCB by the above mentioned technique. Therefore, for analysis of these compounds and their metabolites, we have developed a high performance liquid chromatography (HPLC) based method. Results The extraction of PCNB and HCB from soil and minimal salt medium was carried out with ethyl acetate and hexane respectively with good recoveries (98% for PCNB and 97% for HCB). The validation of the proposed extraction and HPLC method was done by analysis of PCNB and HCB biodegradation and their metabolites identification from anaerobic enriched soil samples. Conclusion A rapid, sensitive and simple HPLC based analytical method was developed for the analysis of PCNB, HCB and their possible intermediates. PMID:22112041

  13. A validated HPLC method for the analysis of herbal teas from three chemotypes of Brazilian Lippia alba.

    PubMed

    Timóteo, Patrícia; Karioti, Anastasia; Leitão, Suzana G; Vincieri, Franco Francesco; Bilia, Anna Rita

    2015-05-15

    Infusions and decoctions of three chemotypes of Lippia alba (Mill.) N. E. Brown (Verbenaceae) were investigated for their quantitative profiles by HPLC-DAD-ESI-MS analyses. An RP-HPLC method was developed which permitted the quality control of the preparations. The correct choice of the column allowed the detailed characterization of the constituents in a total analysis time of 35 min. The HPLC method was accordingly validated for linearity range, LOD, LOQ, accuracy and precision. For the quantitative analysis the three major phytochemical groups were taken into consideration, namely iridoids, phenylpropanoids and flavonoids. Comparative quantitative analyses revealed significant differences among the chemotypes that should be taken into account in the uses of the herbal teas. The developed HPLC-UV assay proved to be an efficient and alternative method for the discrimination of the three chemotypes. This is the first report of detailed analysis of the chemical composition of the constituents of L. alba chemotypes' teas. PMID:25577093

  14. Quantification of lipoic acid from skin samples by HPLC using ultraviolet, electrochemical and evaporative light scattering detectors.

    PubMed

    Campos, Patrícia Mazureki; Praça, Fabíola Silva Garcia; Bentley, Maria Vitória Lopes Badra

    2016-04-15

    Lipoic acid (LA) is an endogenous organosulfur compound with potent antioxidant property. LA is often used as a drug for the treatment of skin disorders. For the accomplishment of topical applications of LA appropriate drug quantification methods are essential. Thus far, no HPLC methods have been reported for the measurement of LA extracted from skin. In this article we report on the development and validation of three sensitive and specific HPLC methods for LA and dihydrolipoic acid (DHLA) using ultraviolet (UV), electrochemical (EC) or evaporative light scattering (ELS) detection. These methods demonstrate different linearity ranges. The chromatographic separations were performed by RP-HPLC (250×4mm, 5μm) with isocratic elution using an acidic mobile phase for the three detection techniques. The lower limits of detection and quantification were 0.04 and 0.08ng LA, respectively, for HPLC coupled to ELS, an innovative detector for LA with high sensitivity. The extraction of LA from skin samples showed recoveries greater than 71%. The recovered LA concentrations from stratum corneum and epidermis+dermis layers were: 5.41±0.56 and 4.92±0.33μg/mL, respectively for HPLC/UV and 6.52±0.49 and 5.01±0.41μg/mL, respectively, for HPLC/EC for the added LA concentration (6.67μg/mL), and 8.88±0.46 and 8.95±0.08μg/mL, respectively, for HPLC/ELS for the added LA concentration (10μg/mL). These three optimized HPLC methods allowed for a simple, rapid and reliable determination of LA in human skin. They should be useful for the development of drug delivery systems for topical applications of LA. PMID:26307348

  15. Exploring the in vitro formation of trimethylarsine sulfide from dimethylthioarsinic acid in anaerobic microflora of mouse cecum using HPLC-ICP-MS and HPLC-ESI-MS

    SciTech Connect

    Kubachka, Kevin M.; Kohan, Michael C.; Herbin-Davis, Karen; Creed, John T. Thomas, David J.

    2009-09-01

    Although metabolism of arsenicals to form methylated oxoarsenical species has been extensively studied, less is known about the formation of thiolated arsenical species that have recently been detected as urinary metabolites. Indeed, their presence suggests that the metabolism of ingested arsenic is more complex than previously thought. Recent reports have shown that thiolated arsenicals can be produced by the anaerobic microflora of the mouse cecum, suggesting that metabolism prior to systemic absorption may be a significant determinant of the pattern and extent of exposure to various arsenic-containing species. Here, we examined the metabolism of {sup 34}S labeled dimethylthioarsinic acid ({sup 34}S-DMTA{sup V}) by the anaerobic microflora of the mouse cecum using HPLC-ICP-MS and HPLC-ESI-MS/MS to monitor for the presence of various oxo- and thioarsenicals. The use of isotopically enriched {sup 34}S-DMTA{sup V} made it possible to differentiate among potential metabolic pathways for production of the trimethylarsine sulfide (TMAS{sup V}). Upon in vitro incubation in an assay containing anaerobic microflora of mouse cecum, {sup 34}S-DMTA{sup V} underwent several transformations. Labile {sup 34}S was exchanged with more abundant {sup 32}S to produce {sup 32}S-DMTA{sup V}, a thiol group was added to yield DMDTA{sup V}, and a methyl group was added to yield {sup 34}S-TMAS{sup V}. Because incubation of {sup 34}S-DMTA{sup V} resulted in the formation of {sup 34}S-TMAS{sup V}, the pathway for its formation must preserve the arsenic-sulfur bond. The alternative metabolic pathway postulated for formation of TMAS{sup V} from dimethylarsinic acid (DMA{sup V}) would proceed via a dimethylarsinous acid (DMA{sup III}) intermediate and would necessitate the loss of {sup 34}S label. Structural confirmation of the metabolic product was achieved using HPLC-ESI-MS/MS. The data presented support the direct methylation of DMTA{sup V} to TMAS{sup V}. Additionally, the detection of

  16. Arsenic-containing fatty acids and hydrocarbons in marine oils - determination using reversed-phase HPLC-ICP-MS and HPLC-qTOF-MS.

    PubMed

    Sele, Veronika; Sloth, Jens J; Holmelid, Bjarte; Valdersnes, Stig; Skov, Kasper; Amlund, Heidi

    2014-04-01

    Arsenolipids are the major arsenic species present in marine oils. Several structures of arsenolipids have been elucidated the last 5 years, demonstrating the chemical complexity of this trace element in the marine environment. Several commercial fish oils and marine oils, ranging in total arsenic concentrations from 1.6 to 12.5 mg kg(-1) oil, were analyzed for arsenolipids using reversed-phase high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry (HPLC-ICP-MS). The arsenolipids were quantified using three different arsenic-containing calibration standards; dimethylarsinate (DMA), triphenylarsinoxide (Ph₃AsO) and a synthesized arsenic-containing hydrocarbon (AsHC) (dimethylarsinoyl nonadecane; C₂₁H₄₃AsO). The observed variation in signal intensity for arsenic during the gradient elution profile in reversed-phase HPLC was compensated for by determining the time-resolved response factors for the arsenolipids. Isotopes of germanium ((74)Ge) and indium ((115)In) were suited as internal standards for arsenic, and were used for verification of the arsenic signal response factors during the gradient elution. Dimethylarsinate was the most suitable calibration standard for the quantification of arsenolipids, with recoveries between 91% and 104% compared to total arsenic measurements in the same extracts. A range of marine oils was investigated, including oils of several fish species, cod liver and seal, as well as three commercial fish oils. The AsHCs - C₁₇H₃₈AsO, C₁₉H₄₂AsO and C₂₃H₃₈AsO - were identified as the major arsenolipids in the extracts of all oils by HPLC coupled with quadrupole time-of-flight mass spectrometry (qTOF-MS). Minor amounts of two arsenic-containing fatty acids (AsFAs) (C₂₃H₃₈AsO₃ and C₂₄H₃₈AsO₃) were also detected in the oils. The sum of the AsHCs and the AsFAs determined in the present study accounted for 17-42% of the total arsenic in the oils. PMID

  17. Optical spectroscopic and reverse-phase HPLC analyses of Hg(II) binding to phytochelatins.

    PubMed

    Mehra, R K; Miclat, J; Kodati, V R; Abdullah, R; Hunter, T C; Mulchandani, P

    1996-02-15

    Optical spectroscopy and reverse-phase HPLC were used to investigate the binding of Hg(II) to plant metal-binding peptides (phytochelatins) with the structure (gammaGlu-Cys)2Gly, (gammaGlu-Cys)3Gly and (gammaGlu-Cys)4Gly. Glutathione-mediated transfer of Hg(II) into phytochelatins and the transfer of the metal ion from one phytochelatin to another was also studied using reverse-phase HPLC. The saturation of Hg(II)-induced bands in the UV/visible and CD spectra of (gammaGlu-Cys)2Gly suggested the formation of a single Hg(II)-binding species of this peptide with a stoichiometry of one metal ion per peptide molecule. The separation of apo-(gammaGlu-Cys)2Gly from its Hg(II) derivative on a C18 reverse-phase column also indicated the same metal-binding stoichiometry. The UV/visible spectra of both (gammaGlu-Cys)3Gly and (gammaGlu-Cys)4Gly at pH 7.4 showed distinct shoulders in the ligand-to-metal charge-transfer region at 280-290 mm. Two distinct Hg(II)-binding species, occurring at metal-binding stoichiometries of around 1.25 and 2.0 Hg(II) ions per peptide molecule, were observed for (gammaGlu-Cys)3Gly. These species exhibited specific spectral features in the charge-transfer region and were separable by HPLC. Similarly, two main Hg(II)-binding species of (gammaGlu-Cys)4Gly were observed by UV/visible and CD spectroscopy at metal-binding stoichiometries of around 1.25 and 2.5 respectively. Only a single peak of Hg(II)-(gammaGlu-Cys)4Gly complexes was resolved under the conditions used for HPLC. The overall Hg(II)-binding stoichiometries of phytochelatins were similar at pH 2.0 and at pH 7.4, indicating that pH did not influence the final Hg(II)-binding capacity of these peptides. The reverse-phase HPLC assays indicated a rapid transfer of Hg(II) from glutathione to phytochelatins. These assays also demonstrated a facile transfer of the metal ion from shorter- to longer-chain phytochelatins. The strength of Hg(II) binding to glutathione and phytochelatins followed the

  18. The metabolism of 4-bromoaniline in the bile-cannulated rat: application of ICPMS (79/81Br), HPLC-ICPMS & HPLC-oaTOFMS

    PubMed Central

    Duckett, Catherine; McCullagh, Michael; Smith, Christopher; Wilson, Ian D

    2015-01-01

    Abstract 1. An excretion balance study was performed following i.p. administration of 4-bromoaniline (50 mg kg−1) to bile-cannulated rats, using bromine-detected (79/81Br) ICPMS for quantification. Approximately 90% of the dose was recovered in urine (68.9 ± 3.6%) and bile (21.4 ± 1.4%) by 48 h post-administration. 2. HPLC-ICPMS (79/81Br) was used to selectively detect and profile the major urinary and biliary-excreted metabolites and determined that the 0–12 h urine contained at least 21 brominated metabolites with 19 bromine-containing peaks observed in the 6–12 h bile samples. 3. The urinary and biliary metabolites were subsequently profiled using HPLC-oaTOFMS. By exploiting the distinctive bromine isotope pattern ca. 60 brominated metabolites were detected in the urine in negative electrospray ionisation (ESI) mode while bile contained ca. 21. 4. While a large number of bromine-containing metabolites were detected, the profiles were dominated by a few major components with the bulk of the 4-bromoaniline-related material in urine accounted for by 4-bromoanaline O-sulfate (∼75% of the total by ICPMS, 84% by TOFMS). In bile a hydroxylated N-acetyl compound was the major metabolite detected, forming some ∼65% of the 4-bromoaniline-related material by ICPMS (37% by TOFMS). PMID:25837688

  19. A rapid and reliable technique for N-nitrosodimethylamine analysis in reclaimed water by HPLC-photochemical reaction-chemiluminescence.

    PubMed

    Fujioka, Takahiro; Takeuchi, Haruka; Tanaka, Hiroaki; Nghiem, Long D; Ishida, Kenneth P; Kodamatani, Hitoshi

    2016-10-01

    A fast and reliable analytical technique was evaluated and validated for determination of N-nitrosodimethylamine (NDMA) formation and rejection by reverse osmosis (RO) membranes in potable water reuse applications. The analytical instrument used in this study is high-performance liquid chromatography (HPLC), photochemical reaction (PR) and chemiluminescence (CL) - namely HPLC-PR-CL. Results reported here show that HPLC-PR-CL can be used to measure NDMA with a similar level of accuracy compared to conventional and more time-consuming techniques using gas chromatography and tandem mass spectrometry detection in combination with solid phase extraction. Among key residual chemicals (i.e. monochloramine, hydrogen peroxide and hypochlorite) in reclaimed wastewater, hypochlorite was the only constituent that interfered with the determination of NDMA by HPLC-PR-CL. However, hypochlorite interference was eliminated by adding ascorbic acid as a reducing agent. Direct injection of ultrafiltration (UF)-treated wastewater samples into HPLC-PR-CL also resulted in an underestimation of the NDMA concentration possibly due to interference by organic substances in the UF-treated wastewater. Accurate determination of NDMA concentrations in UF-treated wastewater was achieved by reducing the sample injection volume from 200 to 20 μL, though this increased the method detection limit from 0.2 to 2 ng/L. In contrast, no interference was observed with RO permeate. These results suggest that RO membranes could remove part of substances that interfere with the NDMA analysis by HPLC-PR-CL. In addition, RO treatment experiments demonstrated that HPLC-PR-CL was capable of evaluating near real-time variation in NDMA rejection by RO. PMID:27423127

  20. Production, HPLC analysis, and in situ apoptotic activities of swainsonine toward lepidopteran, Sf-21 cell line.

    PubMed

    Singh, Digar; Kaur, Gurvinder

    2014-01-01

    Swainsonine, a secondary metabolite from Metarhizium anisopliae has been extensively studied in the complementary areas of therapeutics and toxicology. This work aims to develop a simple UV-HPLC method of analyses for swainsonine in Metarhizium fermentation broth and to explore its in situ entomotoxic activities. The partially purified broth was quantitatively analyzed using middle UV (205 nm)-reverse phase HPLC method with different mobile phases and gradient programmes. Swainsonine was eluted as single peak at (te ) 6.0-6.9 min with average concentration of 4.04 ± 0.52 μg/mL using optimal mobile phase (0.1% trifluoroacetic acid in water and acetonitrile). The mass spectrometry analysis further indicated the characteristic MS1 species for swainsonine, [M+H](+) 174.30 in corresponding HPLC peaks. The antiproliferative effects of swainsonine on lepidopteran, Sf-21 cells were determined through 3-(4, 5-dimethylthia-zol-2-yl)-2, 5-diphenyl tetrazolium bromide (IC50 standard  = 3.90 μM and IC50 purified  = 5.27 μM) and trypan blue dye exclusion (IC50 standard  = 6.91 μM and IC50 purified  = 8.67 μM) assays. The fluorescence activated cell sorting evaluation of Sf-21 cells showed nearly 35% and 42% of population in various apoptotic stages at 36 h, when treated with standard and purified swainsonine, respectively. The morphodimensional field emission scanning electron and atomic force microscopic analyses further confirmed the characteristic apoptotic features like membrane blebbings, ruptures and volume shrinkage in the lepidopteran cells after 24-36 h of post-treatment incubation. The study describes the potential entomotoxic activities of swainsonine and its role in the virulence of Metarhizium spp. PMID:25044730

  1. Optimization and comparison of HPLC and RRLC conditions for the analysis of carbonyl-DNPH derivatives.

    PubMed

    de M Ochs, Soraya; Fasciotti, Maíra; Barreto, Renata P; de Figueiredo, Natália G; Albuquerque, Flávio C; Massa, M Cecília G Pontes; Gabardo, Irene; Pereira Netto, Annibal D

    2010-04-15

    Analytical conditions for the analysis of 15 carbonyl-DNPH derivatives were optimized and compared by high performance liquid chromatography (HPLC) and rapid resolution liquid chromatography (RRLC). Binary, ternary and quaternary mixtures of acetonitrile, isopropanol, methanol, tetrahydrofuran and water were evaluated under RRLC conditions employing a Zorbax Eclipse Plus C18 (50 mm x 4.6 mm x 1.8 microm) column and a Zorbax Eclipse Plus C18 (50 mm x 2.1 mm x 1.8 microm) column. The optimized conditions obtained employing the two RRLC columns were compared with those obtained using a Supelcosil C18 (250 mm x 4.6 mm x 5 microm; Supelco) that is designed for HPLC separation of DNPH derivatives. Chromatograms run with a Zorbax Eclipse Plus C18 (50 mm x 2.1 mm x 1.8 microm) column and a mobile phase composed of isopropanol, methanol, tetrahydrofuran and water led to the best separation conditions considering reduced analysis time (approximately 6 min per run), solvent consumption rate (approximately 2 mL per run) and resolution of propanone, acrolein and propionaldehyde hydrazones. Quantification limits and linear ranges were adequate for direct application of EPA TO-11 conditions in all sets of RRLC and HPLC conditions. The analytical method was applied in the determination of carbonyl compounds (CCs) in Niterói City, RJ, Brazil in samples that were collected during periods of 2h. Formaldehyde (8.22-9.78 ppbv) predominated in all periods followed by acetaldehyde (1.77-3.99ppbv) and propanone (1.89-3.26 ppbv). Heavy CCs such as butyraldehyde and benzaldehyde were also detected in most samples. Total CCs varied along the studied day. The obtained results showed that RRLC can be applied to CCs determination without any change in the conditions of sample preparation of the Method EPA TO-11. PMID:20188957

  2. Development and Validation of HPLC and HPTLC Methods for Determination of Cefoperazone and Its Related Impurities.

    PubMed

    Abdelaleem, Eglal A; Naguib, Ibrahim A; Zaazaa, Hala E; Hussein, Essraa A

    2016-02-01

    Validated sensitive and highly selective methods were developed for the quantitative determination of cefoperazone sodium (CEF) in the presence of its reported impurities; 7-aminocephalosporanic acid (7-ACA) and 5-mercapto-1-methyl-tetrazole (5-MER). Method A is high-performance liquid chromatography (HPLC), where the mixture of CEF and the reported impurities; 7-ACA and 5-MER were separated on a C8 column (5 µm ps, 250 mm × 4.6 i.d.) using methanol:0.05 M KH2PO4 buffer (22.5:77.5 v/v, pH 7.5) as a mobile phase. The three components were detected at 254 nm with a concentration range of 10-90 µg mL(-1) and the mean percentage recovery 99.67% (SD 1.465). Method B is high-performance thin layer chromatography (HPTLC), where the mixture of CEF and the reported impurities were separated on silica gel HPTLC F254 plates using (acetone:methanol:ethyl acetate:2% sodium lauryl sulfate:glacial acetic acid) (3:2:3:0.8:0.2, by volume) as a developing system and scanning at 254 nm over a concentration range of 1-10 µg per band with the mean percentage recovery 99.95% (SD 1.335). The proposed methods were statistically compared with a reported HPLC method with no significant difference regarding accuracy and precision; indicating the ability of the proposed methods to be reliable and suitable for routine analysis of drug product. The proposed HPTLC method proved to be more sensitive, while the HPLC gave more reproducible results besides saving time. PMID:26306573

  3. Gradient HPLC-DAD determination of paracetamol, phenylephrine hydrochloride, cetirizine in tablet formulation.

    PubMed

    Dewani, A P; Shelke, P G; Bakal, R L; Jaybhaye, S S; Chandewar, A V; Patra, S

    2014-05-01

    Present work describes the development and validation of a simple and reliable high-performance liquid chromatography-diode array detection (HPLC-DAD) procedure for the analysis of phenylephrine hydrochloride (PHE), paracetamol (PAR) and cetirizine dihydrochloride (CET), in pharmaceutical mixture. The method was applied successfully on tablet dosage form. Effective chromatographic separation of PHE, PAR and CET was achieved using a Kinetex-C18 (4.6, 150 mm, 5 mm) column with gradient elution of the mobile phase composed of 10 mM phosphate buffer (pH 3.3) and acetonitrile. The elution was a 3 step gradient elution program step-1 started initially with 2% (by volume) acetonitrile and 98% phosphate buffer (pH 3.3) for first 2 min. In step-2 acetonitrile concentration changed linearly to 20% upto 12 min the analysis was concluded by step-3 changing acetonitrile to 2% upto 20 min. The reliability and analytical performance of the proposed HPLC procedure were statistically validated with respect to linearity, ranges, precision, accuracy, selectivity and robustness. Calibration curves were linear in the ranges 5-15, 250-750 and 2.5-7.5 μg/ml for PHE, PAR and CET, with correlation coefficients >0.9996. The validated HPLC method was applied to a pharmaceutical mixture of a marketed preparation tablet in which the analytes were successfully quantified with good recovery values with no interfering peaks from the excipents. PMID:24132702

  4. Gradient HPLC-DAD determination of two pharmaceutical mixtures containing the antihistaminic drug ebastine.

    PubMed

    Haggag, Rim S; Belal, Tarek S

    2012-01-01

    This work describes the development, validation and application of a simple and reliable high-performance liquid chromatography-diode array detection (HPLC-DAD) procedure for the analysis of two pharmaceutical mixtures. The first mixture contains the antihistaminic drug ebastine (EBS) and the famous sympathomimetic drug pseudoephedrine hydrochloride (PSD), and the second mixture is composed of EBS and another sympathomimetic agent, phenylephrine hydrochloride (PHR). Effective chromatographic separation of EBS, PSD and PHR was achieved using a Zorbax SB-C8 (4.6 × 250 mm, 5 μm) column with gradient elution of the mobile phase composed of 0.05M phosphoric acid and acetonitrile. The gradient elution started with 20% (by volume) acetonitrile, ramped up linearly to 90% in 5 min, then kept constant until the end of the run. The mobile phase was pumped at a flow rate of 1 mL/min. The multiple wavelength detector was set at 254 (for EBS and PSD) and 274 nm (for PHR) and quantification of the analytes was based on measuring their peak areas. The retention times for PHR, PSD and EBS were approximately 2.5, 2.9 and 7.1 min, respectively. The reliability and analytical performance of the proposed HPLC procedure were statistically validated with respect to linearity, ranges, precision, accuracy, selectivity, robustness and detection and quantification limits. Calibration curves were linear in the ranges 5-100, 100-1,000 and 10-200 µg/mL for EBS, PSD and PHR, respectively, with correlation coefficients > 0.9996. The validated HPLC method was applied to the analysis of the two pharmaceutical mixtures in laboratory-made tablets in which the analytes were successfully quantified with good recovery values and no interfering peaks were encountered from the inactive ingredients. Finally, the proposed method made use of DAD as a tool for peak identity and purity confirmation. PMID:22677488

  5. 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.

  6. Evaluation of tamoxifen and metabolites by LC-MS/MS and HPLC methods.

    PubMed

    Heath, D D; Flat, S W; Wu, A H B; Pruitt, M A; Rock, C L

    2014-01-01

    Epidemiological and laboratory evidence suggests that quantification of serum or plasma levels of tamoxifen and its metabolites, 4-hydroxy-N-desmethyl-tamoxifen (endoxifen), Z-4-hydroxytamoxifen (4HT), N-desmethyl-tamoxifen (ND-tam), is a clinically useful tool in the assessment and monitoring of breast cancer status in patients taking adjuvant tamoxifen. A liquid chromatographic mass spectrometric method (LC-MS/MS) was used to measure the blood levels of tamoxifen and its metabolites. This fully automated analytical method is specific, accurate and sensitive. The LC-MS/MS automated technique has now become a widely accepted reference method. This study analysed a randomly selected batch of blood samples from participants enrolled in a breast cancer study to compare results from this reference method in 40 samples with those obtained from a recently developed high-performance liquid chromatography (HPLC) method with fluorescence detection. The mean (SD) concentrations for the LC-MS/MS method (endoxifen 12.6 [7.5] ng/mL, tamoxifen 105 [44] ng/mL, 4-HT 1.9 [1.0] ng/mL, ND-tam 181 [69] ng/mL) and the HPLC method (endoxifen 13.1 [7.8] ng/mL, tamoxifen 108 [55] ng/mL, 4-HT 1.8 [0.8] ng/mL, ND-tam 184 [81] ng/mL) did not show any significant differences. The results confirm that the HPLC method offers an accurate and comparable alternative for the quantification of tamoxifen and tamoxifen metabolites. PMID:24693573

  7. Determination of azide impurity in sartans using reversed-phase HPLC with UV detection.

    PubMed

    Gričar, Maja; Andrenšek, Samo

    2016-06-01

    A simple and robust, gradient HPLC method was developed for determination of azide ppm (μgg(-1)) levels in different sartans (irbesartan, candesartan, valsartan). The sartan was dissolved in 0.1M NaOH. Then pH was adjusted to 4.5 with 20% H3PO4 followed by dilution with water. Precipitated API was removed by filtration using 0.45μm membrane PVDF (Polyvinylidene Fluoride) membrane filter, and supernatant was analyzed by gradient elution HPLC at room temperature with Hydro RP HPLC 250×4.6mm, 4μm column and UV detection at 205nm. The best sensitivity was achieved by UV detection cell with 60mm optical path length: LOD 0.17μgg(-1) and LOQ 0.84μgg(-1) for azide. The USP requirement for maximum azide content in irbesartan is 10μgg(-1). The analytical method was validated as per International Conference on Harmonization (ICH) guidelines with respect to system precision, intraday precision (repeatability), intermediate precision (ruggedness), linearity, quantitation limit, detection limit, accuracy, standard and sample solution stability, robustness and selectivity/specificity. The method was linear in the range from LOQ (0.84μgg(-1)) to 101μgg(-1) of azide. The correlation coefficient was 0.9999 and bias on y-axis for 84μgg(-1) test concentration was 0.33%. The accuracy of the method was established based on the recovery obtained between 94.0% and 103.0% for azide. Standard and sample solutions were stable for at least 48h at room temperature and in refrigerator. The method was found to be robust for variation in column temperature (±5°C) and mobile phase flow rate (±0.2mLmin(-1)) and selective for anions such as bromide, nitrate, nitrite, formate and acetate. PMID:26999319

  8. Capillary HPLC/QTOF-MS for characterizing complex naphthenic acid mixtures and their microbial transformation.

    PubMed

    Bataineh, M; Scott, A C; Fedorak, P M; Martin, J W

    2006-12-15

    A rapidly expanding oil sands industry in Canada produces and indefinitely stores large volumes of toxic aqueous tailings containing high concentrations of naphthenic acids (NAs), a complex mixture of naturally occurring aliphatic or alicyclic carboxylic acids. Although there is an acknowledged need to reduce the environmental risks posed by NAs, little is understood about their environmental fate due to a lack of appropriate analytical methods. A dilute-and-shoot reversed-phase capillary HPLC/QTOF-MS method was developed that combines high specificity and sensitivity, quantitative capabilities, the ability to detect novel transformation products, and new structural information within each NA isomer class. HPLC separated NAs, based on carbon number, degree of cyclization, and the extent of alkyl branching, and in so doing increased analytical sensitivity up to 350-fold while providing additional specificity compared to infusion techniques. For tailings water, an interlaboratory study revealed many differences in isomer class profiles compared to an established GC/MS method, much of which was attributed to the misclassification of oxidized NAs (i.e., NA + O) by low-resolution GC/MS. HPLC/QTOF-MS enabled the detection of oxidized products in the same chromatographic run, and Van Krevelen diagrams were adapted to visualize the complex data. A marked decrease of retention times was evident in Syncrude tailings water compared to a commercial mixture, suggesting that tailings water is dominated by highly persistent alkyl-substituted isomers. A biodegradation study revealed that tailings water microorganisms preferentially deplete the least alkyl-substituted fraction and may be responsible for the NA profile in aged tailings water. PMID:17165827

  9. Identification of chemical markers in Cordyceps sinensis by HPLC-MS/MS.

    PubMed

    Hu, Hankun; Xiao, Ling; Zheng, Baogen; Wei, Xin; Ellis, Alexis; Liu, Yi-Ming

    2015-10-01

    Authentication and quality assessment of Cordyceps sinensis, a precious and pricey natural product that offers a variety of health benefits, is highly significant. To identify effective chemical markers, authentic C. sinensis was thoroughly screened by using HPLC-MS/MS. In addition to many previously reported ingredients, two glycosides, i.e., cyclo-Ala-Leu-rhamnose and Phe-o-glucose, were detected for the first time in this material. Six ingredients detected, including cordycepin, D-mannitol, Phe, Phe-o-glucose, cyclo-Gly-Pro, and cyclo-Ala-Leu-rhamnose, were selected as a collection of chemical markers. An HPLC-MS/MS method was developed to simultaneously quantify them with sensitivity and specificity. The method had limits of detection ranging from 0.008 μg mL(-1) for cordycepin to 0.75 μg mL(-1) for cyclo-Gly-Pro. Recovery was found between 96 and 103 % in all tests. To evaluate the effectiveness of the marker collection proposed, five authentic C. sinensis samples and five samples of its substitutes were analyzed. Cordycepin, D-mannitol, and Phe were found present in all samples. The contents ranged from 0.0076 to 0.029 % (w/w) for cordycepin, 0.33 to 18.9 % for mannitol, and 0.0013 to 0.642 % for Phe. Interestingly, the two glycosides, Phe-o-glucose and cyclo-Ala-Leu-rhamnose, were detected only in authentic C. sinensis samples. These results indicated that the proposed protocol based on HPLC-MS/MS quantification of the markers might have a great potential in authentication and quality assessment of C. sinensis. Graphical abstract Chemical markers of C. sinensis identified in this work. PMID:26302964

  10. Establishment of an HPLC identification system for detection of counterfeit steroidal drugs.

    PubMed

    Shi, Ya-Qin; Yao, Jing; Liu, Feng; Hu, Chang-Qin; Yuan, Jun; Zhang, Qi-Ming; Jin, Shao-Hong

    2008-03-13

    A set of simple HPLC methods employing UV detection were developed for detection of counterfeit drugs by the qualitative and quantitative analysis of nine steroidal drugs, ethinylestradiol, diethylstilbestrol, norethisterone, norgestrel, methyltestosterone, medroxyprogesterone acetate, progesterone, testosterone propionate and nilestriol. The methods were based on studies of the relationships between the retention factors (k) of the nine compounds and the percentages of water to methanol in the mobile phases on a reverse phase Alltima C(18) column giving reliable separation of the compounds under three sets of chromatographic conditions. The methods were validated using statistical tests and were used on nine commercial samples for detection of possible counterfeit drugs. PMID:18215486

  11. Screening of Panamanian Plant Extracts for Pesticidal Properties and HPLC-Based Identification of Active Compounds

    PubMed Central

    Guldbrandsen, Niels; De Mieri, Maria; Gupta, Mahabir; Seiser, Tobias; Wiebe, Christine; Dickhaut, Joachim; Reingruber, Rüdiger; Sorgenfrei, Oliver; Hamburger, Matthias

    2015-01-01

    A library of 600 taxonomically diverse Panamanian plant extracts was screened for fungicidal, insecticidal, and herbicidal activities. A total of 19 active extracts were submitted to HPLC-based activity profiling, and extracts of Bocconia frutescens, Miconia affinis, Myrcia splendens, Combretum aff. laxum, and Erythroxylum macrophyllum were selected for the isolation of compounds. Chelerythrine (2), macarpine (3), dihydrosanguinarine (5), and arjunolic acid (8) showed moderate-to-good fungicidal activity. Myricetin-3-O-(6’’-O-galloyl)-β-galactopyranoside (13) showed moderate insecticidal activity, but no compound with herbicidal activity was identified. PMID:26839818

  12. An HPLC assay for the determination of ketoconazole in common pharmaceutical preparations.

    PubMed

    Low, A S; Wangboonskul, J

    1999-11-01

    An HPLC method is described using octadecylsilica (3 microns) with an acetonitrile phosphate buffer mobile phase containing diethylamine which is capable of separating ketoconazole [(+/-)-cis-1-acetyl-4-(4[2-(dichlorophenyl)-2- (1H-imidazol-1-ylmethyl)-1,3-dioxolan-4-yl]methoxy]phenyl)pi perazine] from four related compounds, (R049223, R063600, R053165 and R039519) and from excipients in tablets, cream and shampoo. The method was validated using an external calibration method for tablets, shampoo and creams and a standard addition method for cream. The limits of detection for the related compounds in the presence of ketoconazole are also reported. PMID:10746318

  13. Chemical Constituents from Daphne giraldii Nitsche and Their Contents Simultaneous Determination by HPLC

    PubMed Central

    Huyiligeqi; Dong, Xiaoxv; Yang, Chunjing; Xu, Guanling; Cao, Sali; Fu, Jing; Lin, Longfei; Ni, Jian

    2016-01-01

    Daphne giraldii Nitsche (Thymelaeaceae) is widely distributed in the Chinese provinces of Shaanxi, Gansu, and Qinghai, which has been used in Chinese folk medicine to treat ache and rheumatism. Pharmacologic tests have revealed that the plant has anti-inflammatory, analgesic, and anticancer activities. However, there is still not enough systemic investigation on the chemical constituents and the method for the contents simultaneous determination in D. giraldii. Therefore, the isolation and characterization of the compounds from the stem barks of this plant were reported. Moreover, a facile, accurate, and reliable method has been developed and validated for their simultaneous determination using HPLC-DAD. PMID:27190543

  14. Atropisomeric determination of chiral hydroxylated metabolites of polychlorinated biphenyls using HPLC-MS

    PubMed Central

    2013-01-01

    Background Polychlorinated biphenyls (PCBs) are a group of environmental persistent organic pollutants, which can be metabolized into a series of metabolites, including hydroxylated metabolites (OH-PCBs) in biota. Nineteen of 209 PCB congeners can form chiral stable isomers. However, atropisomeric determination of the hydroxylated metabolites of these chiral PCBs has never been reported by LC methods. In this work, a novel HPLC-MS method was developed to detect five chiral OH-PCBs (4OH-PCB91, 5OH-PCB91, 4OH-PCB95, 5OH-PCB95 and 5OH-PCB149) using HPLC-MS without a derivatization step. Results The influences of column-type, column temperature, flow rate and ratio of the mobile phase on the atropisomeric separation were investigated in detail. In the final method, calibration curves, based on peak areas against concentration, were linear in a range of 1–100 ng mL-1 of five chiral OH-PCBs with correlation coefficients ranging from 0.9996 to 0.9999 for all atropisomers of OH-PCBs. The relative standard deviations measured at the 10.0 ng mL-1 level for atropisomers of five chiral OH-PCBs were in the range of 0.60-7.55% (n = 5). Calculated detection limits (S/N = 3) of five chiral OH-PCBs were between 0.31 and 0.60 ng mL-1 for all OH-PCB atropisomers. Conclusion This HPLC-MS method was developed to detect chiral OH-PCBs and further successfully applied to measure OH-PCB atropisomer levels and enantiomeric fractions (EFs) in rat liver microsomal samples. The results from LC-MS method were highly consistent with those from GC-ECD method. It is the first time to report these OH-PCB atropisomers detected in microsomes by HPLC-MS. The proposed method might be applied also to detect chiral OH-PCBs in environmental samples and for metabolites of PCBs in vivo. PMID:24360245

  15. A comparative study for PSP toxins quantification by using MBA and HPLC official methods in shellfish.

    PubMed

    Ben-Gigirey, B; Rodríguez-Velasco, M L; Otero, A; Vieites, J M; Cabado, A G

    2012-10-01

    Commission Regulation (EC) N° 2074/2005 recognises the biological method as the reference method for Paralytic Shellfish Poisoning (PSP) toxins detection in molluscs. It was amended by Commission Regulation (EC) N° 1664/2006 that accepted the so-called Lawrence method as an alternative to the reference method. The goal of this study was to compare AOAC Official Methods of Analysis 959.08 (Biological method) and 2005.06 (Prechromatographic Oxidation and Liquid Chromatography with fluorescence detection) in samples with different toxin profiles. The influence of extraction solvent in the total samples toxicity was also evaluated. A total of 40 samples including mussels, clams, scallops, razor-clams, cockles, oysters and barnacles were analysed by both official methods. Samples were selected with Alexandrium and Gymnodinium toxic profiles, from different origin and including several presentations: fresh, frozen, canned and boiled. Acetic and hydrochloric acid extractions were performed in all samples and the extracts were simultaneously analysed by both methods. Most samples were naturally contaminated and two samples were spiked. Comparison of both official methods, mouse bioassay (MBA) with HCl extraction and Liquid Chromatography with fluorescence detection (HPLC-FLD) with acetic acid extraction, led to an 85% of consistent results regarding compliance with legal limit, including samples below and above it. The linear correlation coefficient was r² = 0.69 and the paired t test (two tails, α = 0.05) indicated that there were not significant differences among both sets of data. Nevertheless, toxicity differences were found in several samples. In 15 out of 18 shellfish with a Gymnodinium toxic profile, higher toxicity levels were obtained by MBA. This fact was more evident in 7 samples, partially related to the lack of standards and the impossibility of analysing dc-NEO, C1, 2 and GTX6 at the beginning of the study. However, other factors concerning the extraction

  16. Regularities of Anthocyanins Retention in RP HPLC for “Water–Acetonitrile–Phosphoric Acid” Mobile Phases

    PubMed Central

    Deineka, V. I.; Deineka, L. A.; Saenko, I. I.

    2015-01-01

    The influence of exchange of HCOOH (System 2) by phosphoric acid (System 1) for acidification of the “acetonitrile–water” mobile phases for reversed-phase HPLC of anthocyanins was investigated in the framework of relative retention analysis. The differences and similarities of anthocyanins separation were revealed. It has been shown that some common features of the quantitative relationships may be used for preliminary anthocyanins structure differentiation, according to the number of OH-groups in anthocyanidin backbone as well as to a number of saccharide molecules in glycoside radicals in position 3 of the anthocyanin without MS detection. PMID:25692073

  17. Qualitative analysis of the chemical constituents in Hedyotis diffusa by HPLC-TOF-MS.

    PubMed

    Wang, Xu; Cheng, Weiming; Yao, Xinning; Guo, Xingjie

    2012-01-01

    A high performance liquid chromatography-time-of-flight-mass spectrometry (HPLC-TOF-MS) method was developed for analysing the chemical constituents in Hedyotis diffusa, which is widely used as a traditional Chinese medicine (TCM) in the field of cancer treatment. The compounds were identified either by comparing the retention time and mass spectrometry data with those of reference compounds or by analysing mass spectrometry data and retrieving reference literature. Among the detected chromatographic peaks, nine components were unambiguously identified, most of which were iridoids. This study is expected to provide an effective and reliable pattern for comprehensive and systematic characterisation of the complex TCM systems. PMID:21838590

  18. Solid phase extraction and HPLC analysis of toxic components eluted from methyl methacrylate dental materials.

    PubMed

    Shintani, H; Tsuchiya, T; Hata, Y; Nakamura, A

    1993-01-01

    Methyl methacrylate polymer (PolyMMA) is widely used as the composite resin for the dental plate. During the fabrication process of PolyMMA for the polymerization reaction, benzoylperoxide (BPO) and N,N-dimethyl p-toluidine (DMPT) are added as the initiator and the stimulator, respectively. Because these compounds exhibit toxicity as well as a residue potential, their use raises concerns regarding human safety. The degree of dissolution into serum was determined to evaluate risk to the user. Analysis was by HPLC combined with solid-phase extraction using a C-18 column. The eluted compounds were found to be in the order of 10 to 100 ppm. PMID:8492570

  19. Simultaneous quantitation of tobramycin and colistin sulphate by HPLC with evaporative light scattering detection.

    PubMed

    Clarot, I; Storme-Paris, I; Chaminade, P; Estevenon, O; Nicolas, A; Rieutord, A

    2009-08-15

    A rapid and simple method for the simultaneous determination of tobramycin and colistin sulphate in a pharmaceutical formulation by reversed phase HPLC and evaporative light scattering detection is described. Chromatographic separation was carried out in gradient mode using a Zorbax SB C18 column (150mmx4mm, 3.5microm) with mobile phases of acetonitrile and water containing trifluoroacetic at 1ml/min. The method was validated using methodology described by the International Conference of Harmonization. The method was shown to be specific, precise, accurate and linear. Real samples were analyzed to demonstrate the applicability of the chromatographic method in a routine use. PMID:19372021

  20. Design and Prototype of an Automated Column-Switching HPLC System for Radiometabolite Analysis.

    PubMed

    Vasdev, Neil; Collier, Thomas Lee

    2016-01-01

    Column-switching high performance liquid chromatography (HPLC) is extensively used for the critical analysis of radiolabeled ligands and their metabolites in plasma. However, the lack of streamlined apparatus and consequently varying protocols remain as a challenge among positron emission tomography laboratories. We report here the prototype apparatus and implementation of a fully automated and simplified column-switching procedure to allow for the easy and automated determination of radioligands and their metabolites in up to 5 mL of plasma. The system has been used with conventional UV and coincidence radiation detectors, as well as with a single quadrupole mass spectrometer. PMID:27548189

  1. Determination of arctiin and arctigenin in Fructus Arctii by reverse-phase HPLC.

    PubMed

    Sun, W J; Sha, Z F; Gao, H

    1992-01-01

    The fruits of Arctium lappa L. is an often-used herbal drug in traditional Chinese medicine for the treatment of common cold caused by wind and heat. This drug contained many constituents, principally arctiin, with arctigenin in smaller amount. In this work, arctiin has been isolated from the fruits of Arctium lappa, and then enzymolyzed into arctigenin. The obtained arctiin and arctigenin were characterized and then used as standards for their determination in the crude drug by HPLC. The method is simple, rapid and accurate. PMID:1442089

  2. Analysis of several iridoid and indole precursors of terpenoid indole alkaloids with a single HPLC run.

    PubMed

    Dagnino, D; Schripsema, J; Verpoorte, R

    1996-06-01

    An isocratic HPLC system is described which allows the separation of the iridoid and indole precursors of terpenoid indole alkaloids, which are present in a single crude extract. The system consists of a column of LiChrospher 60 RP select B 5 microm, 250 x 4 mm (Merck) with an eluent of 1% formic acid-acetonitrile-trichloroacetic acid (100:10:0.25, v:v:w) at a flow of 1.2 ml/min. In the suspension cultures of Catharanthus roseus secologanin and tryptophan were detected. in the cultures of Tabernaemontana divaricata loganin, tryptophan, and tryptamine accumulated. PMID:17252445

  3. Determination of the design space of the HPLC analysis of water-soluble vitamins.

    PubMed

    Wagdy, Hebatallah A; Hanafi, Rasha S; El-Nashar, Rasha M; Aboul-Enein, Hassan Y

    2013-06-01

    Analysis of water-soluble vitamins has been tremendously approached through the last decades. A multitude of HPLC methods have been reported with a variety of advantages/shortcomings, yet, the design space of HPLC analysis of these vitamins was not defined in any of these reports. As per the food and drug administration (FDA), implementing the quality by design approach for the analysis of commercially available mixtures is hypothesized to enhance the pharmaceutical industry via facilitating the process of analytical method development and approval. This work illustrates a multifactorial optimization of three measured plus seven calculated influential HPLC parameters on the analysis of a mixture containing seven common water-soluble vitamins (B1, B2, B6, B12, C, PABA, and PP). These three measured parameters are gradient time, temperature, and ternary eluent composition (B1/B2) and the seven calculated parameters are flow rate, column length, column internal diameter, dwell volume, extracolumn volume, %B (start), and %B (end). The design is based on 12 experiments in which, examining of the multifactorial effects of these 3 + 7 parameters on the critical resolution and selectivity, was carried out by systematical variation of all these parameters simultaneously. The 12 basic runs were based on two different gradient time each at two different temperatures, repeated at three different ternary eluent compositions (methanol or acetonitrile or a mixture of both). Multidimensional robust regions of high critical R(s) were defined and graphically verified. The optimum method was selected based on the best resolution separation in the shortest run time for a synthetic mixture, followed by application on two pharmaceutical preparations available in the market. The predicted retention times of all peaks were found to be in good match with the virtual ones. In conclusion, the presented report offers an accurate determination of the design space for critical resolution in the

  4. Analysis of multiple sweeteners and their degradation products in lassi by HPLC and HPTLC plates.

    PubMed

    George, V; Arora, S; Wadhwa, B K; Singh, A K

    2010-08-01

    A solid phase extraction method using C18 cartridges was standardized for the isolation of multiple sweeteners (aspartame, acesulfame-K and saccharin) and their degradation products (diketopiperazine, Lphenylalanine, acetoacetamide and 2-sulfobenzoic acid) from lassi. Analytical conditions for HPLC were standardized over C18 column using UV detector for the simultaneous separation and estimation of multiple sweeteners and their degradation products in lassi sample isolates. A simple cartridge free method was developed for the isolation of sucralose from lassi. Method was also standardized for qualitative detection and quantitative estimation of sucralose over amino and silica gel plates of HPTLC. PMID:23572661

  5. Determination of daumone in mouse plasma by HPLC/MS-MS.

    PubMed

    Noh, Keumhan; Park, Jong Hee; Kim, Minkyu; Jung, Mankil; Lee, Hwa Jeong; Kwon, Kwang-il; Kang, Wonku; Ha, Hunjoo

    2012-02-01

    Daumone, a pheromone secreted by Caenorhabditis elegans, is an essential regulator of chemosensory processes in development and aging. A quantification method using HPLC/MS-MS was developed for the determination of daumone in mouse plasma. After simple protein precipitation with acetonitrile including methaqualone (an internal standard), the analytes were chromatographed on a reversed-phase column and detected by liquid chromatography/tandem mass spectrometry with electrospray ionization. The accuracy and precision of the assay were in accordance with FDA regulations for validation of bioanalytical methods. This method was applied to measure the plasma daumone concentrations following a 5-week repeated oral administration of daumone in mice. PMID:21594879

  6. A systematic approach to the accurate quantification of selenium in serum selenoalbumin by HPLC-ICP-MS.

    PubMed

    Jitaru, Petru; Goenaga-Infante, Heidi; Vaslin-Reimann, Sophie; Fisicaro, Paola

    2010-01-11

    In this paper, two different methods are for the first time systematically compared for the determination of selenium in human serum selenoalbumin (SeAlb). Firstly, SeAlb was enzymatically hydrolyzed and the resulting selenomethionine (SeMet) was quantified using species-specific isotope dilution (SSID) with reversed phase-HPLC (RP-HPLC) hyphenated to (collision/reaction cell) inductively coupled plasma-quadrupole mass spectrometry (CRC ICP-QMS). In order to assess the enzymatic hydrolysis yield, SeAlb was determined as an intact protein by affinity-HPLC (AF-HPLC) coupled to CRC ICP-QMS. Using this approach, glutathione peroxidase (GPx) and selenoprotein P (SelP) (the two selenoproteins present in serum) were also determined within the same chromatographic run. The levels of selenium associated with SeAlb in three serum materials, namely BCR-637, Seronorm level 1 and Seronorm level 2, obtained using both methods were in a good agreement. Verification of the absence of free SeMet, which interferes with the SeAlb determination (down to the amino acid level), in such materials was addressed by analyzing the fraction of GPx, partially purified by AF-HPLC, using RP-HPLC (GPx only) and size exclusion-HPLC (SE-HPLC) coupled to CRC ICP-QMS. The latter methodology was also used for the investigation of the presence of selenium species other than the selenoproteins in the (AF-HPLC) SelP and SeAlb fractions; the same selenium peaks were detected in both control and BCR-637 serum with a difference in age of ca. 12 years. It is also for the first time that the concentrations of selenium associated with SeAlb, GPx and SelP species in such commercially available serums (only certified or having indicative levels of total selenium content) are reported. Such indicative values can be used for reference purposes in future validation of speciation methods for selenium in human serum and/or inter-laboratory comparisons. PMID:20005320

  7. Use of cyanopropyl-bonded hplc column for bioassay-directed fractionation of organic extracts from incinerator emissions

    SciTech Connect

    DeMarini, D.M.; Williams, R.W.; Brooks, L.R.; Taylor, M.S.

    1992-01-01

    The present study has shown that cyanopropyl-(CN) bonded silica HPLC columns are applicable for the fractionation of mass and mutagenic activity of organic extracts from some incinerator emissions. Dichloromethane-extractable organics from particles emitted by two different municipal waste incinerators and by a pilot-scale rotary kiln incinerator that was combusting polyethylene were fractionated by HPLC, and the mutagenicity of the fractions was determined by means of a microsuspension mutagenicity assay with Salmonella TA98. The CN-bonded silica columns provided high (80-100 percent) mass and mutagenicity recoveries for most emission extracts, and it fractionated the mutagenic activity. The results suggest that the emissions from municipal waste incinerators contain a high amount of direct-acting (-S9) mutagenic activity that is resolvable by HPLC using CN-bonded silica. Sub-fractionation of selected mutagenic HPLC fractions and subsequent analysis by gas chromatography/mass spectroscopy can be used to identify mutagenic species within complex incinerator emissions. The coupling of microsuspension bioassays to HPLC fractionation should be a useful tool for this type of analysis.

  8. Quantitative lipopolysaccharide analysis using HPLC/MS/MS and its combination with the limulus amebocyte lysate assay.

    PubMed

    Pais de Barros, Jean-Paul; Gautier, Thomas; Sali, Wahib; Adrie, Christophe; Choubley, Hélène; Charron, Emilie; Lalande, Caroline; Le Guern, Naig; Deckert, Valérie; Monchi, Mehran; Quenot, Jean-Pierre; Lagrost, Laurent

    2015-07-01

    Quantitation of plasma lipopolysaccharides (LPSs) might be used to document Gram-negative bacterial infection. In the present work, LPS-derived 3-hydroxymyristate was extracted from plasma samples with an organic solvent, separated by reversed phase HPLC, and quantitated by MS/MS. This mass assay was combined with the limulus amebocyte lysate (LAL) bioassay to monitor neutralization of LPS activity in biological samples. The described HPLC/MS/MS method is a reliable, practical, accurate, and sensitive tool to quantitate LPS. The combination of the LAL and HPLC/MS/MS analyses provided new evidence for the intrinsic capacity of plasma lipoproteins and phospholipid transfer protein to neutralize the activity of LPS. In a subset of patients with systemic inflammatory response syndrome, with documented infection but with a negative plasma LAL test, significant amounts of LPS were measured by the HPLC/MS/MS method. Patients with the highest plasma LPS concentration were more severely ill. HPLC/MS/MS is a relevant method to quantitate endotoxin in a sample, to assess the efficacy of LPS neutralization, and to evaluate the proinflammatory potential of LPS in vivo. PMID:26023073

  9. Quantitative lipopolysaccharide analysis using HPLC/MS/MS and its combination with the limulus amebocyte lysate assay[S

    PubMed Central

    Pais de Barros, Jean-Paul; Gautier, Thomas; Sali, Wahib; Adrie, Christophe; Choubley, Hélène; Charron, Emilie; Lalande, Caroline; Le Guern, Naig; Deckert, Valérie; Monchi, Mehran; Quenot, Jean-Pierre; Lagrost, Laurent

    2015-01-01

    Quantitation of plasma lipopolysaccharides (LPSs) might be used to document Gram-negative bacterial infection. In the present work, LPS-derived 3-hydroxymyristate was extracted from plasma samples with an organic solvent, separated by reversed phase HPLC, and quantitated by MS/MS. This mass assay was combined with the limulus amebocyte lysate (LAL) bioassay to monitor neutralization of LPS activity in biological samples. The described HPLC/MS/MS method is a reliable, practical, accurate, and sensitive tool to quantitate LPS. The combination of the LAL and HPLC/MS/MS analyses provided new evidence for the intrinsic capacity of plasma lipoproteins and phospholipid transfer protein to neutralize the activity of LPS. In a subset of patients with systemic inflammatory response syndrome, with documented infection but with a negative plasma LAL test, significant amounts of LPS were measured by the HPLC/MS/MS method. Patients with the highest plasma LPS concentration were more severely ill. HPLC/MS/MS is a relevant method to quantitate endotoxin in a sample, to assess the efficacy of LPS neutralization, and to evaluate the proinflammatory potential of LPS in vivo. PMID:26023073

  10. Structural characterization of low level degradants in aztreonam injection and an innovative approach to aid HPLC method validation.

    PubMed

    Ye, Qingmei; Ding, Wei; Rinaldi, Frank; Huang, Yande; Miller, Scott A; Bolgar, Mark

    2016-05-30

    Three new degradants have been identified from drug product and active pharmaceutical ingredient stability samples of aztreonam, a marketed synthetic monocyclic beta-lactam antibiotic. The degradants were detected following the implementation of a new, more selective HPLC method for the determination of impurities and degradants. The new method was developed in response to changes in the regulatory requirement for mature products. Two of the new unknown Degradants (I and II) were observed in chromatograms from stability samples of aztreonam injection. The third new Degradant (III) was observed during a stability study of the aztreonam active pharmaceutical ingredient. These degradants were structurally characterized. A small amount (ca. 1-3mg) of each degradant was isolated via preparative HPLC for structure elucidation using accurate MS, one and two-dimensional NMR spectroscopy. The small amount of each NMR sample was then reused as a standard for HPLC purity/impurity method validation. Their exact concentrations were determined using quantitative NMR which enabled the execution of the quantitative elements of the HPLC method validation. This innovative approach eliminated the need to isolate or synthesize larger quantities of markers for HPLC/UV method validation, thus saving significant time and reducing costs. PMID:26991056

  11. Determination of the cis-trans isomerization barriers of L-alanyl-L-proline in aqueous solutions and at water/hydrophobic interfaces by on-line temperature-jump relaxation HPLC and dynamic on-column reaction HPLC.

    PubMed

    Shibukawa, Masami; Miyake, Ayaka; Eda, Sayaka; Saito, Shingo

    2015-09-15

    Proline cis-trans isomerization is known to play a key role in the rate-determining steps of protein folding. It is thus very important to understand the influence of environments, not only bulk solutions but also microenvironments such as interfaces, on the isomerization reaction of proline peptides. Here we present two HPLC methods for measurements of kinetic and equilibrium parameters for the isomerization reactions in bulk solutions and at liquid/solid interfaces. On-line temperature-jump relaxation HPLC (T-jump HPLC) allows the determination of forward and reverse rate constants of the isomerization in a bulk solution by monitoring the whole time course of conversion of pure isomers from both sides of the reaction, in contrast to other HPLC and capillary zone electrophoresis as well as spectrometric and calorimetric methods, which use a mixture of the isomers. We can then determine cis-trans isomerization barriers of the peptide at liquid/solid interfaces from the kinetic data obtained by dynamic on-column reaction HPLC and T-jump HPLC. We observed that the interconversion around the peptide bond for l-alanyl-l-proline (Ala-Pro) in water is accelerated at the surfaces of an alkyl-bonded silica and a poly(styrene-divinylbenzene) copolymer resin, and this is caused by a remarkable decrease in the enthalpy of activation. The molecular structures of the cis and trans forms of Ala-Pro estimated by quantum mechanics calculation reveal that an equilibrium shift toward the cis form as well as the rapid isomerization of Ala-Pro at the water/hydrophobic interfaces can be attributed to the lower polarity of the interfacial water at the surfaces of the hydrophobic materials compared to that of bulk water. PMID:26320351

  12. Validation of AN Hplc-Dad Method for the Classification of Green Teas

    NASA Astrophysics Data System (ADS)

    Yu, Jingbo; Ye, Nengsheng; Gu, Xuexin; Liu, Ni

    A reversed phase high performance liquid chromatography (RP-HPLC) separation coupled with diode array detection (DAD) and electrospray ionization mass spectrometer (ESI/MS) was developed and optimized for the classification of green teas. Five catechins [epigallocatechin (EGC), epigallocatechin gallate (EGCG), epicatechin (EC), gallocatechin gallate (GCG), epicatechin gallate (ECG)] had been identified and quantified by the HPLC-DAD-ESI/MS/MS method. The limit of detection (LOD) of five catechins was within the range of 1.25-15 ng. All the analytes exhibited good linearity up to 2500 ng. These compounds were considered as chemical descriptors to define groups of green teas. Chemometric methods including principal component analysis (PCA) and hierarchical cluster analysis (HCA) were applied for the purpose. Twelve green tea samples originating from different regions were subjected to reveal the natural groups. The results showed that the analyzed green teas were differentiated mainly by provenance; HCA afforded an excellent performance in terms of recognition and prediction abilities. This method was accurate and reproducible, providing a potential approach for authentication of green teas.

  13. Development of a HPLC Method for the Quantitative Determination of Capsaicin in Collagen Sponge

    PubMed Central

    Guo, Chun-Lian; Chen, Hong-Ying; Cui, Bi-Ling; Chen, Yu-Huan; Zhou, Yan-Fang; Peng, Xin-Sheng; Wang, Qin

    2015-01-01

    Controlling the concentration of drugs in pharmaceutical products is essential to patient's safety. In this study, a simple and sensitive HPLC method is developed to quantitatively analyze capsaicin in collagen sponge. The capsaicin from sponge was extracted for 30 min with ultrasonic wave extraction technique and methanol was used as solvent. The chromatographic method was performed by using isocratic system composed of acetonitrile-water (70 : 30) with a flow rate of 1 mL/min and the detection wavelength was at 280 nm. Capsaicin can be successfully separated with good linearity (the regression equation is A = 9.7182C + 0.8547; R2 = 1.0) and perfect recovery (99.72%). The mean capsaicin concentration in collagen sponge was 49.32 mg/g (RSD = 1.30%; n = 3). In conclusion, the ultrasonic wave extraction method is simple and the extracting efficiency is high. The HPLC assay has excellent sensitivity and specificity and is a convenient method for capsaicin detection in collagen sponge. This paper firstly discusses the quantitative analysis of capsaicin in collagen sponge. PMID:26612986

  14. Validation of an HPLC method on short columns to assay ketoconazole and formaldehyde in shampoo.

    PubMed

    Nguyen, Minh Nguyet A; Tallieu, L; Plaizier-Vercammen, J; Massart, D L; Vander Heyden, Y

    2003-04-24

    An HPLC method to determine simultaneously ketoconazole and formaldehyde in an anti-dandruff shampoo, originally developed on a long column, was transferred to two short columns with similar stationary phase properties, but with a length of at the most 30% of the initial one. Using the conventional column as reference, the fast HPLC methods on the short columns were validated. The validation characteristics consisted of selectivity, linearity range, precision (repeatability and time-different intermediate precision), bias and robustness. For the ketoconazole assay, linearity for peak area was found in the concentration range up to 0.20 mg/ml. For formaldehyde, two calibration ranges (0-10 x 10(-5) and 0-10 x 10(-4)%) were linear, both for peak area and height. The assays for both ketoconazole and formaldehyde in these ranges showed no bias and an acceptable precision, although the precision found with the short columns was slightly worse than with the long one. The robustness tests were performed applying a Plackett-Burman design. For the ketoconazole assay, 6 factors were examined in a 12 experiments design and for formaldehyde, 11 factors in 16 experiments. The methods were found to be robust. Despite the somewhat less good precision the transfer seems to be successful and the obtained assays on the short columns are applicable for fast routine analysis. PMID:12852444

  15. Reversed phase-HPLC for rapid determination of polyphenols in flowers of rose species.

    PubMed

    Kumar, Neeraj; Bhandari, Pamita; Singh, Bikram; Gupta, Ajai P; Kaul, Vijay K

    2008-02-01

    A rapid, simple, sensitive, robust, and improved HPLC method was developed and validated for determination of 10 polyphenols, namely gallic acid, catechin, epicatechin, rutin, m-coumaric acid, quercitrin, myricetin, quercetin, apigenin, and kaempferol in fresh flowers of Rosa bourboniana and R. brunonii and in both fresh flowers and marc (left after industrial distillation of rose oil) of R. damascena. Six polyphenols, gallic acid, rutin, quercitrin, myricetin, quercetin, and kaempferol, were detected and quantified in all extracts. The chromatographic separation of 10 polyphenols was achieved in less than 16 min by RP-HPLC (Phenomenex, Luna C18 (2) column, 5 microm, 250 mm x 4.6 mm) using linear gradient elution of water and acetonitrile (0.02% trifluroacetic acid) with a flow rate of 1 mL/min at lambda 280 nm. Standard calibration curves were linear in the range of 0.39-500 microg/mL. Good results were achieved with respect to repeatability (RSD <3%) and recovery (98.6-100.8%). The method was validated for linearity, accuracy, repeatability, LOD, and LOQ. PMID:18172921

  16. Production of L-(1-/sup 11/C)valine by HPLC resolution

    SciTech Connect

    Washburn, L.C.; Sun, T.T.; Byrd, B.L.; Callahan, A.P.

    1982-01-01

    Based on a recently developed analytical technique, preparative high-performance liquid chromatographic (HPLC) resolution of DL-(1-/sup 11/C)valine has been achieved. A conventional reverse-phase HPLC column and a chiral mobile phase (aqueous solution of L-proline, cupric acetate, and sodium acetate) were used. The copper can be removed from the L-valine fraction by precipitation as the sulfide, and final purification by cation-exchange chromatography yields L-(1-/sup 11/C)valine in a form that is acceptable for clinical positron tomographic studies. This purification method does not remove the L-proline introduced in the resolution process, but added L-proline did not affect the tissue distribution of L-(1-/sup 14/C)valine in rats. We have produced up to 60 mCi of L-(1-/sup 11/C)valine in an overall synthesis and resolution time of 50 min. This procedure should be adaptable to the rapid resolution of other C-/sup 11/-labeled amino acid racemates.

  17. Production of L-(1-/sup 11/C)valine by HPLC resolution

    SciTech Connect

    Washburn, L.C.; Sun, T.T.; Byrd, B.L.; Callahan, A.P.

    1982-01-01

    Based on a recently developed analytical technique, preparative high-performance liquid chromatographic (HPLC) resolution of DL-(1-/sup 11/C)valine has been achieved. A conventional reverse-phase HPLC column and a chiral mobile phase (aqueous solution of L-proline, cupric acetate, and sodium acetate) were used. The copper can be removed from the L-valine fraction by precipitation as the sulfide, and final purification by cation-exchange chromatography yields L-(1-/sup 11/C)valine in a form that is acceptable for clinical positron tomographic studies. This purification method does not remove the L-proline introduced in the resolution process, but added L-proline did not affect the tissue distribution of L-(1-/sup 14/C)valine in rats. We have produced up to 60 mCi of L-(1-/sup 11/C)valine in an overall synthesis and resolution time of 50 min. This procedure should be adapable to the rapid resolution of other C-11-labeled amino acid racemates.

  18. Validation of an HPLC-MS/MS and Wipe Procedure for Mitomycin C Contamination

    PubMed Central

    B’Hymer, C.; Connor, T.H.; Stinson, D.; Pretty, J.R.

    2015-01-01

    A high-performance liquid chromatography-tandem mass spectrometric (HPLC-MS/MS) method was developed for the determination of mitomycin C, an anticancer drug, from contamination on various surfaces. Mitomycin C is often used in various forms of intraperitoneal chemotherapy, and operating room healthcare worker exposure to this drug is possible. The surface testing method consisted of a wiping procedure utilizing a solution of 20/45/35 (v/v/v) of acetonitrile-isopropanol-water made 0.01 M in ammonium citrate (apparent pH 7.0). The wipe solutions were analyzed by means of HPLC-MS/MS using a reversed-phase gradient system and electrospray ionization in positive ion-mode with a triple-quadrupole mass spectrometric detector. Accuracy and precision of this method were demonstrated by a series of recovery studies of both spiked solutions and extracted wipes from various surfaces (stainless steel, vinyl and Formica®) spiked with known levels of mitomycin C. Recoveries of spiked solutions containing the analyte demonstrate mean recoveries (accuracy) ranged from 93 to 105%. Precision as measured by the relative standard deviation (%RSD) of multiple samples (n=10) at each concentration level demonstrated values of 7.5% or less. The recoveries from spiked surfaces varied from 30 to 99%. The limit of detection (LOD) for this methodology is approximately 2 ng/100 cm2 equivalent surface area, and the limit of quantitation (LOQ) is approximately 6 ng/100 cm2. PMID:25129062

  19. Determination of glucosamine and its derivatives released from photocrosslinked gelatin hydrogels using HPLC.

    PubMed

    Suo, Hairui; Xu, Kedi; Zhang, Hengyi; Zheng, Xiaoxiang

    2016-02-01

    A simple, accurate and validated reverse-phase high-performance liquid chromatography (HPLC)/UV method is developed for the determination of glucosamine hydrochloride (GlcN), N-acetyl-glucosamine (NAG) and N-acryloyl-glucosamine (AGA) released from photocrosslinked gelatin hydrogels. The HPLC separation was achieved on a Shimadzu InertSustain amino column (250 × 4.6 mm, 5 µm particle size) at room temperature using a mobile phase of acetonitrile-phosphate buffer (75:25, v/v, pH 6.0) at a flow rate of 1.0 mL/min and UV detection of 194 nm. The method was validated for specificity, linearity, limit of detection and quantification, accuracy, precision, extraction recovery and solution stability. The calibration curves were with excellent linearity, with correlation coefficients (R(2)) >0.999 for all three drugs. The intra- and inter-day variation was <3.10% and the relative error was between -1.43 and 1.78%. The extraction recovery results ranged from 94.62 to 99.33%, demonstrating the absence of matrix effect. The sample and standard solutions were stable for more than 2 months. The method was successfully used for the analysis of released properties of drugs physically encapsulated and chemically crosslinked in the gelatin hydrogels. PMID:26053464

  20. Simultaneous analysis of ellagic acid and coenzyme Q(10) by derivative spectroscopy and HPLC.

    PubMed

    Ratnam, D Venkat; Bhardwaj, V; Kumar, M N V Ravi

    2006-09-15

    Antioxidants are gaining tremendous interest as chemopreventive as well as chemotherapeutic agents. Ellagic acid (EA) is a plant derived compound with very poor solubility in water and very low octanol/water partition coefficient and coenzyme Q(10) (CoQ(10)) is a highly lipophilic compound, which is synthesized in the body and can be derived from food supplements as well. The new insights in the combination therapy are promising a better future in many challenging diseases. Synergism is among the key advantages of combination therapy apart from decreased intensity of unwanted effects of a compound, increased patient compliance and reduction in cost of therapy. EA and CoQ(10) supplementation in combination will be beneficial in strengthening the weakened antioxidant defense system in many diseases related to oxidative stress. Here we report first derivative UV spectroscopic and HPLC methods for the simultaneous analysis of these two agents in pharmaceutical preparations. Results obtained indicate that the derivative spectroscopy is as efficient as HPLC method in quantitative analysis. Retention of ellagic acid can be increased using PEG bonded column which is poorly retained on C(18) column. PEG column can be used for rapid simultaneous analysis of EA and CoQ(10), which are having diverse physicochemical properties. PMID:18970780

  1. HPLC determination and clinical significance of serum prednisone in patients with nephrotic syndrome

    PubMed Central

    Chen, Chun-Mei; Xia, Yun-Cheng; Zhang, Xu-Guang; Peng, Can-Hui; Liu, Fu-You; Peng, You-Ming; Sun, Lin

    2014-01-01

    Aim: A rapid protocol is necessary to determine the serum concentrations of prednisone. Methods: The HP1100 high-performance liquid chromatographic (HPLC) system was employed. The HP Lichrosphere C8 column (250 mm × 4 mm, i.d., 5 μm particle size) was used. The mobile phase was methanol, tetrahydrofuran and water in the ratio 25:25:50. The flow rate was 1.0 ml/min. The sample was monitored by UV absorbance at 240 nm. Acetanilide was used as the internal standard, and methanol was added into the serum for depositing the protein. Results: The chromatography was effective and was not interfered with by the serum components. Good linearity was observed, within the range of 10-500 μg/L for prednisone, and the detection limit was 5 μg/L. The serum concentrations of prednisone between the nephrotic syndrome (NS) group and the control group were significantly different (P < 0.05), while there was no significant difference between the females and males of the NS group (P > 0.05). The serum ncentration of prednisone in the steroid-resistant group was lower than that in the steroid-sensitive group (P < 0.05). Conclusions: HPLC is a practical and reliable method to determine the serum concentration of prednisone with high accuracy, precision, linearity and repeatability. PMID:25664064

  2. 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. PMID:23745967

  3. UPLC and HPLC of caffeoyl esters in wild and cultivated Arctium lappa L.

    PubMed

    Haghi, Ghasem; Hatami, Alireza; Mehran, Mehdi

    2013-05-01

    Analytical methods including ultra-performance liquid chromatography (UPLC) and high-performance liquid chromatography (HPLC) with photodiode array (PDA) detector were developed for the analysis of caffeoylquinic acid derivatives in seeds, leaves and roots of Arctium lappa L. Separation was performed on C(18) column utilising 5% (v/v) acetic acid in water and acetonitrile at 330 nm. Both methodologies were validated in terms of linearity, precision, and recovery. The results showed that the major advantages of UPLC, over HPLC were the fast analysis, narrow peaks, high sensitivity, and reduction of solvent consumption. Subsequently the methods were applied for the identification and quantification of chlorogenic acid (5-CQA) and 1,5-dicaffeoylquinic acid (1,5-DCQA) as main compounds in samples. The total phenolic content of samples ranged from 3.93 to 14.13 g of 5-CQA equivalent/100g dry weight (DW). There was a significant variability from 89 to 571 mg/100g for 5-CQA and 48 to 486 mg/100g for 1,5-DCQA in dry material. PMID:23265494

  4. Detection of Abnormal Hemoglobin Variants by HPLC Method: Common Problems with Suggested Solutions

    PubMed Central

    Pant, Leela; Kalita, Dipti; Singh, Sompal; Kudesia, Madhur; Mendiratta, Sumanlata; Mittal, Meenakshi; Mathur, Alka

    2014-01-01

    Thalassemia and thalassemic hemoglobinopathies pose serious health problem leading to severe morbidity and mortality in Indian population. Plethora of hemoglobin variants is prevalent in multiethnic Indian population. The aim of the present study was to analyze laboratory aspects, namely, hematological profile and HPLC findings of the hemoglobin variants detected, and to discuss problems that we faced in diagnosis in a routine clinical laboratory. We screened a total of 4800 cases in a hospital based population of North India in a 2-years period of by automated HPLC method using the Variant Hemoglobin Testing System (Variant II Beta Thalassemia Short Program, Bio-Rad Laboratories) under the experimental conditions specified by the manufacturer. Whole blood in EDTA was used and red cell indices were determined using automated hematology analyzer. We detected 290 cases with abnormal variants in which beta thalassemia was the most common followed by hemoglobin E. Here, we discuss the laboratory aspects of various hemoglobin disorders and diagnostic difficulties in cases like borderline HbA2 values, presence of silent mutation, alpha thalassemia gene, and few rare variants which at times require correlation with genetic study. Special attention was given to HbA2 level even in presence of a structural variant to rule out coinheritance of beta thalassemia gene. PMID:27351019

  5. Efficient HPLC method for the determination of nicarbazin, as dinitrocarbanilide in broiler liver.

    PubMed

    Capurro, Emiliana; Danaher, Martin; Anastasio, Aniello; Cortesi, Maria Luisa; O'Keeffe, Michael

    2005-08-01

    A simple, fast and reliable HPLC-UV method has been developed for the determination of dinitrocarbanilide residues in broiler liver. Liver samples (2 g) were extracted with two portions of acetonitrile (10 and 5 ml), defatted with hexane and evaporated to dryness under nitrogen. Extracts were reconstituted in acetonitrile-water (70/30, v/v, 500 microl), loaded onto C18 solid phase (SPE) cartridges and eluted with acetonitrile-water (70/30, v/v, 2.5 ml) into clean test-tubes. Extracts were evaporated to dryness and reconstituted in acetonitrile-water (80/20, v/v, 500 microl). An aliquot of the extract was assayed by high performance liquid chromatography (HPLC) with UV detection at 350 nm. The method was validated according to EU guidelines using liver tissues fortified at levels of 100, 200 and 300 microg/kg, with dinitrocarbanilide. The decision limit (CC(alpha)) and the detection capability (CC(beta)) were calculated from the within laboratory repeatability data to be 228 and 266 microg/kg, respectively. The mean recovery was typically >70% and the limits of quantitation was 12.5 microg/kg (based on the lowest standard on the calibration curve). PMID:16005689

  6. Simultaneous HPLC Quantitative Analysis of Nine Bioactive Constituents in Scirpus Yagara Ohwi. (Cyperaceae).

    PubMed

    Zhang, Jianfang; Zou, Nuoshu; Liang, Qiaoli; Tang, Yamin; Duan, Jin'ao

    2016-03-01

    The tuber of Scirpus yagara Ohwi. (Cyperaceae) has long been used in traditional Chinese medicine (TCM). Several chemical constituents isolated from it possess a variety of physiologically activities such as anti-inflammatory, antitumor and antioxidant. A simultaneous high-performance liquid chromatography (HPLC) analysis was developed and validated for the determination of nine active components in tubers and aerial parts of S. yagara. The analysis was performed on a YMC-Pack ODS-A column (4.6 × 250 mm, 5 μm, 30 nm) with a multilinear gradient mobile phase of water-formic acid (100 : 0.2, v/v) and methanol. The established HPLC method was validated in terms of linearity, sensitivity, precision, accuracy, recovery and stability. All analyzed components were detected in the whole tested samples, and the contents of most components in the aerial parts were even higher than those in the tubers. Moreover, the best harvest period was discovered to be November, which is different from the traditional. The method developed was successfully applied for simultaneous qualitative and quantitative analysis of nine active components in S. yagara. PMID:26657411

  7. 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.

  8. Quantification of neutral human milk oligosaccharides by graphitic carbon HPLC with tandem mass spectrometry

    PubMed Central

    Bao, Yuanwu; Chen, Ceng; Newburg, David S.

    2012-01-01

    Defining the biologic roles of human milk oligosaccharides (HMOS) requires an efficient, simple, reliable, and robust analytical method for simultaneous quantification of oligosaccharide profiles from multiple samples. The HMOS fraction of milk is a complex mixture of polar, highly branched, isomeric structures that contain no intrinsic facile chromophore, making their resolution and quantification challenging. A liquid chromatography-mass spectrometry (LC-MS) method was devised to resolve and quantify 11 major neutral oligosaccharides of human milk simultaneously. Crude HMOS fractions are reduced, resolved by porous graphitic carbon HPLC with a water/acetonitrile gradient, detected by mass spectrometric specific ion monitoring, and quantified. The HPLC separates isomers of identical molecular weights allowing 11 peaks to be fully resolved and quantified by monitoring mass to charge (m/z) ratios of the deprotonated negative ions. The standard curves for each of the 11 oligosaccharides is linear from 0.078 or 0.156 to 20 μg/mL (R2 > 0.998). Precision (CV) ranges from 1% to 9%. Accuracy is from 86% to 104%. This analytical technique provides sensitive, precise, accurate quantification for each of the 11 milk oligosaccharides and allows measurement of differences in milk oligosaccharide patterns between individuals and at different stages of lactation. PMID:23068043

  9. Determination of mitragynine in urine matrices by bar adsorptive microextraction and HPLC analysis.

    PubMed

    Neng, N R; Ahmad, S M; Gaspar, H; Nogueira, J M F

    2015-11-01

    Bar adsorptive microextraction combined with liquid desorption followed by high performance liquid chromatography with diode array detection (BAµE-LD/HPLC-DAD) is proposed for the determination of the psychoactive alkaloid mitragynine (MG) in human urine matrices. By using a modified N-vinylpyrrolidone polymer (P2) sorbent phase, high selectivity and efficiency is achieved. Assays performed by BAµE(P2)-LD/HPLC-DAD on 25 mL water samples spiked at the 8.0 µg L(-1) level yielded average recoveries around 100% of MG, under optimized experimental conditions. The analytical performance showed good precision (RSD<15%), appropriated detection limits of 0.10 µg L(-1) and linear dynamic ranges (0.6-24.0 μg L(-1)) with convenient determination coefficients of 0.9924. By using the standard addition method, the application of the present methodology for the determination of MG in human urine matrices after Kratom consumer, allowed very good performances. The proposed methodology proved to be a suitable alternative to monitor MG in biological fluid matrices, showing to be easy to implement, reliable, sensitive and requiring low sample volumes, when compared with other sorbent-based methods. PMID:26452798

  10. The effect of assay methods on plasma levels and pharmacokinetics of theophylline: HPLC and EIA.

    PubMed Central

    Ishizaki, T; Watanabe, M; Morishita, N

    1979-01-01

    1 The effects of two assay methods, HPLC and EIA, on theophylline plasma levels (n = 254) and pharmacokinetics (n = 6) were examined on blood samples obtained from asthmatic patients and normal adult male volunteers. 2 The standard curves obtained and the plasma level values during plasma level monitoring of theophylline measured with two methods are well correlated each other within concentration range of 2.5 to 20.0 microgram/ml (P less than 0.001). EIA, however in general, appears to give a lower value than HPLC. 3 The values of plasma theophylline half-life and clearance analyzed using a two-compartment open system model were found different between the two assay methods and dissimilar to those previously reported by using ultraviolet method. 4 The sampling end-point and/or assay sensitivity particularly to measure a lower level of theophylline (less than 2.5 microgram/ml) can influence the pharmacokinetics for a potent bronchodilator with a narrow therapeutic margin, theophylline. PMID:375957

  11. Determination of trimebutine and desmethyl-trimebutine in human plasma by HPLC.

    PubMed

    Lavit, M; Saivin, S; Boudra, H; Michel, F; Martin, A; Cahiez, G; Labaune, J P; Chomard, J M; Houin, G

    2000-07-01

    A simple and sensitive HPLC method has been developed to measure trimebutine (CAS 39133-31-8, maleate: CAS 34140-59-5) and its main metabolite desmethyl-trimebutine in human plasma. The method was validated according to the Washington Consensus Conference on the Validation of Analytical Methods. It involved extraction of the plasma with n-hexane containing 2-pentanol, followed by reversed-phase HPLC using a Partisil ODS2 10 microns column and UV detection at 265 nm. The retention times of the internal standard (procaine), desmethyl-trimebutine and trimebutine were 2.4, 4.3 and 6.5 min, respectively. The standard curves were linear from 20 ng.ml-1 (limit of quantitation) to 5000 ng.ml-1 for both compounds. The coefficient of variation for all the criteria of validation were less than 15%. The extraction recoveries obtained for trimebutine and desmethyl-trimebutine were about 90%. Both compounds were very stable upon storage in plasma. The method was tested by measuring the plasma concentrations following oral administration to humans during a bioequivalence study and was shown suitable for pharmacokinetic studies. PMID:10965422

  12. HPLC study of the impurities present in different ursodeoxycholic acid preparations: comparative evaluation of four detectors.

    PubMed

    Roda, A; Gatti, R; Cavrini, V; Cerrè, C; Simoni, P

    1993-08-01

    The use of HPLC with different detectors has been investigated for the analysis of bile acid impurities present in four different commercially available ursodeoxycholic acid preparations. The bile acids were efficiently separated by C18 reversed-phase HPLC using methanol-water (3:2, v/v) as the mobile phase. The detectors used for bile acid detection were: UV at 200 nm refractive index (RI) and an evaporative light scattering mass detector (ELSD II). A prederivatization method with the formation of a fluorescent naphthacyl ester has also been used. GC-MS analysis of Me-TMS bile acid derivatives was included as a reference method. The four ursodeoxycholic acid samples were 98-99% pure. The main impurities present in the samples were chenodeoxycholic acid and to a lesser extent lithocholic acid. Only one sample was found to be almost 100% pure using all the detectors. Significant agreement of the data was found between RI, ELSD II detectors and the fluorescent method; the UV detector was unsuitable for use in this method. The analytical performances of the four detectors for bile acid analysis are reported and discussed. When the four-detector data were compared with the GC-MS method, reasonable agreement resulted. Discordant results were found in the quantitation of trace impurities like lithocholic acid and/or other minor bile acids present in amounts less than 0.1%. PMID:8257741

  13. Analysis of selected stilbenes in Polygonum cuspidatum by HPLC coupled with CoulArray detection.

    PubMed

    Benová, Blanka; Adam, Martin; Onderková, Katerina; Královský, Josef; Krajícek, Milan

    2008-07-01

    The roots of three varieties of Polygonum cuspidatum were analyzed for resveratrol and its analogs. The powder of the dried roots was extracted with aqueous ethanol (60% v/v) and the extracts obtained were analyzed using RP HPLC with coulometric detection. A simple HPLC method with a multichannel CoulArray detector was developed for the determination of four stilbenes: resveratrol, its glucoside piceid, piceatannol, and its glucoside astringin. Analyses were carried out on a LiChrospher C18 (125 x 4.6 mm id, particle size 5 microm) column with a mobile phase of ammonium acetate (pH 3) and ACN in gradient mode. Four compounds were monitored by a CoulArray electrochemical detector. Potentials of eight electrochemical cells in series were set in the range of 200-900 mV. Optimization of the mobile phase pH was performed. Calibration curves showed good linearity with correlation coefficients (r(2))--more than 0.9975. PMID:18646269

  14. Isolation and quantification of a new tuliposide (tuliposide D) by HPLC in Alstroemeria.

    PubMed

    Christensen, L P; Kristiansen, K

    1995-09-01

    From aqueous extracts of flowers, stems and leaves of 1 Brazilian and 15 Chilean Alstroemeria species, the content of a new tuliposide, named tuliposide D, was determined by isocratic reversed-phase high-performance liquid chromatography (RP-HPLC), using distilled water:methanol (80:20) as mobile phase. The compound was detected by a UV-detector at 208 nm. Tuliposide D was found in almost all Alstroemeria species investigated, although in very different amounts. Most species contained relatively small amounts of tuliposide D, especially in the leaves. However, A. hookeri ssp. cummingiana, A. presliana ssp. presliana, A. pseudospathulata and A. revoluta contained large amounts of tuliposide D in all plant parts. Tuliposide D was identified as 1,6-di-(4-hydroxy-2-methylenebutanoate)-beta-D-glucopyranose by UV, FAB-MS, 1H- and 13C-NMR. The content of the allergens 6-tuliposide A and tulipalin A was also determined by RP-HPLC and the possibility that tuliposide D is a further causative agent of allergic contact dermatitis in Alstroemeria is discussed. PMID:8565461

  15. Quality control of Gardeniae Fructus by HPLC-PDA fingerprint coupled with chemometric methods.

    PubMed

    Yin, Fangzhou; Wu, Xiaoyan; Li, Lin; Chen, Yan; Lu, Tuling; Li, Weidong; Cai, Baochang; Yin, Wu

    2015-01-01

    The ripe fruits of Gardenia jasminoides Ellis have been used as traditional Chinese medicine to treat diseases for a long history. Lines of evidence demonstrate that multiple active constituents are responsible for the therapeutic effects of this herbal medicine. However, effective methods for quality control of this herbal medicine are still lacking. In this study, a high-performance liquid chromatography (HPLC) fingerprint analysis was performed on a SinoChrom ODS-BP C18 column (4.6 mm × 250 mm, 5 μm) at 30°C with mobile phase of aqueous solution with 0.1% formic acid and acetonitrile. On the basis of the chromatographic data from 32 batches samples, the HPLC fingerprint pattern containing 27 common peaks was obtained. Among these common peaks, seven peaks were identified by the electrospray ionization-mass spectrometry as geniposidic acid, genipin-1-β-gentiobioside, chlorogenic acid, geniposide, rutin, crocin-1 and crocin-2 and the contents of these seven compounds were simultaneously determined. Finally, chemometric methods including hierarchical clustering analysis and principal component analysis were successfully applied to differentiate the samples from six producing regions. In sum, the data, as described in this study, offer valuable information for the quality control and proper use of Gardeniae Fructus. PMID:26071608

  16. UV and circular dichroism thermal lens microscope for integrated chemical systems and HPLC on microchip

    NASA Astrophysics Data System (ADS)

    Mawatari, Kazuma; Kitamori, Takehiko

    2005-09-01

    Thermal lens microscope (TLM) is our original sensitive detector for non-fluorescent molecules in microspace. The principle is based on absorption of light followed by photothermal process. TLM has been successfully applied tosensitive detection on microchip, and TLM enabled various applications combined with microchip technologies. We are now developing HPLC microchips as one of the important separation techniques for analysis and synthesis. For HPLC microchip systems, direct and sensitive UV detection on microchip becomes key technology. Therefore, we extended applicability of TLM from visible to UV light absorbing samples by pulse UV laser excitation (UV-TLM). Quasi- continuous wave (QCW) method was applied for lock-in amplifier detection. By applying UV-TLM for biomolecules separation and detection, about two orders of higher sensitivity was achieved compared with UV spectrophotometer. For synthesis on microchip, recognition and detection of chiral samples become important in pharmaceutical field. Therefore, function of TLM was extended for selective detection of chiral samples by utilizing polarization modulation of excitation beam and resultant circular dichroism of sample (CD-TLM). The chirality of samples was detected selectively on microchip with two orders higher sensitivity than CD spectrophotometer. Finally, we explained the instrumentation using fiber optics and micro lens technology for achieving a miniaturized practical device.

  17. Simultaneous quantification of 19 ginsenosides in black ginseng developed from Panax ginseng by HPLC-ELSD.

    PubMed

    Sun, Bai-Shen; Gu, Li-Juan; Fang, Zhe-Ming; Wang, Chun-yan; Wang, Zhen; Lee, Mi-Ra; Li, Zheng; Li, Jing-Jie; Sung, Chang-Keun

    2009-08-15

    A high-performance liquid chromatographic method with evaporative light scattering detection (HPLC-ELSD) has been developed to identify and quantify 19 ginsenosides (Rg(1), Re, Rf, Rb(1), Rc, Rb(2), Rd, F(4), Rg(6), Rk(3), Rh(4), 20(S)-, 20(R)-Rg(3), 20(S)-, 20(R)-Rs(3), Rk(1), Rg(5), Rs(4), and Rs(5)) in black ginseng (BG, Korean white ginseng that was subjected to nine cycles of steam treatment). Ultrasonication is employed for sample preparation, and the analysis is achieved on a Discovery C(18) column using gradient elution of CH(3)CN-H(2)O-CH(3)COOH without buffer in 40min. The method was validated by linearity (r(2)> or =0.9994), precision (92.0-107.5%), intra- and inter-day accuracy (R.S.D.<3.21%), and limit of detection (LOD< or =93ng). The quantification method was applied to analyze the composition of ginsenosides in Korean white, red, and black ginsengs. During the preparatory process of BG, ginsenosides transform into constituents of low polarity by hydrolysis, isomerization, and dehydration at C-20, and hydrolysis also occurs at C-3 or C-6. The validated HPLC method is expected to provide the basis for the quality assessment of ginseng products. PMID:19394786

  18. Differentiation and authentication of Panax ginseng, Panax quinquefolius, and ginseng products by using HPLC/MS.

    PubMed

    Chan, T W; But, P P; Cheng, S W; Kwok, I M; Lau, F W; Xu, H X

    2000-03-15

    An LC/MS-based method is established for the differentiation and authentication of specimens and commercial samples of Panax ginseng (Oriental ginseng) and Panax quinquefolius (American ginseng). This method is based on the separation of ginsenosides present in the ginseng methanolic extracts using high-performance liquid chromatography (HPLC), followed by detection with electrospray mass spectrometry. Differentiation of ginsenosides is achieved through simultaneous detection of intact ginsenoside molecular ions and the ions of their characteristic thermal degradation products. An important parameter used for differentiating P. ginseng and P. quinquefolius is the presence of ginsenoside Rf and 24-(R)-pseudoginsenoside F11 in the RICs of Oriental and American ginsengs, respectively. It is important to stress that ginsenoside Rf and 24(R)-pseudoginsenoside F11, which possess the same molecular weight and were found to have similar retention times under most LC conditions, can be unambiguously distinguished in the present HPLC/MS method. The method developed is robust, reliable, reproducible, and highly sensitive down to the nanogram level. PMID:10740871

  19. Combination of HPLC and 252-Cf plasma desorption mass spectrometry for identifying composition of ginseng tinctures.

    PubMed

    Elkin, Y N; Makhankov, V V; Uvarova, N L; Bondarenko, P V; Zubarev, R A; Knysh, A N

    1993-03-01

    The 252-Cf plasma desorption mass spectrometry (252-Cf PDMS) determination or confirmation of the ginsenoside saponins has been proposed to investigate the composition of high performance liquid chromatography (HPLC) peaks of ginseng tinctures and galenic preparations. That ionization technique is well suitable for the analysis of natural mixtures of these saponins. The 252-Cf PD mass spectra of standard ginsenosides Rb1, Rb2, Rc, Re, Rg1, Rd, NG-R2, Z-R1 contain the peaks of two types of ions, namely, molecular adduct ions (MAI) and aglycone ions. By mass the latter may be referred to either protopanaxadiol or protopanaxatriol. The masses of MAI and aglycone ions are determined by the carbohydrate chains. The collected HPLC fractions of P ginseng tincture can be tested for content of ginsenosides. After studying two MAI peaks from the 252-Cf PD mass spectra of the basic ginsenosides, an example of distinction between two galenic preparations from different Panax has been shown. PMID:8352021

  20. Extraction and Determination of Cyproheptadine in Human Urine by DLLME-HPLC Method

    PubMed Central

    Maham, Mehdi; Kiarostami, Vahid; Waqif-Husain, Syed; Abroomand-Azar, Parviz; Tehrani, Mohammad Saber; Khoeini Sharifabadi, Malihe; Afrouzi, Hossein; Shapouri, MahmoudReza; Karami-Osboo, Rouhollah

    2013-01-01

    Novel dispersive liquid-liquid microextraction (DLLME), coupled with high performance liquid chromatography with photodiode array detection (HPLC-DAD) has been applied for the extraction and determination of cyproheptadine (CPH), an antihistamine, in human urine samples. In this method, 0.6 mL of acetonitrile (disperser solvent) containing 30 μL of carbon tetrachloride (extraction solvent) was rapidly injected by a syringe into 5 mL urine sample. After centrifugation, the sedimented phase containing enriched analyte was dissolved in acetonitrile and an aliquot of this solution injected into the HPLC system for analysis. Development of DLLME procedure includes optimization of some important parameters such as kind and volume of extraction and disperser solvent, pH and salt addition. The proposed method has good linearity in the range of 0.02-4.5 μg mL-1 and low detection limit (13.1 ng mL-1). The repeatability of the method, expressed as relative standard deviation was 4.9% (n = 3). This method has also been applied to the analysis of real urine samples with satisfactory relative recoveries in the range of 91.6-101.0%. PMID:24250605

  1. [Determination of benzyl glucosinolate in Lepidium meyenii from different regions by HPLC].

    PubMed

    Tang, Lin; Yin, Hong-jun; Si, Cong-cong; Hu, Xiao-yan; Long, Zheng-hai

    2015-12-01

    The content of benzyl isothiocyanate (BITC) which as the enzymatic hydrolysis product of benzyl glucosinolate through thioglucosidase was determined by HPLC. The content of benzyl isothiocyanate (BITC) which as the enzymatic hydrolysis product of benzyl glucosinolate through thioglucosidase was determined by HPLC. The chromatography condition was as follows: Kaseisorb LC ODS 2000 (4.6 mm x 150 mm, 5 min) column with the mobile phase of acetonitrile(A)-water( B) under gradient elution (0-5 min, 3%-8% A; 5-9 min, 8%-48% A; 9-23 min, 48%-62% A; 23-28 min, 62%-99% A); the flow rate was 1.0 mL x min(-1) with 10 microL injection volume; detection wavelength was 246 nm and temperature of column was 40 degrees C. The content of benzyl glucosinolate was in the range of 10.76-17.91 g x L(-1). The method is simple, accurate and good reproducibility which can be used for the determination of benzyl glucosinolate in Lepidium meyenii, effectively. PMID:27141661

  2. Tissue distribution of ochratoxin A as determined by HPLC and ELISA and histopathological effects in chickens.

    PubMed

    Biró, Krisztina; Solti, László; Barna-Vetró, Ildikó; Bagó, György; Glávits, Róbert; Szabó, Erzsébet; Fink-Gremmels, Johanna

    2002-04-01

    Ochratoxin A is a common feed contaminant, which may impair animal health and may lead to residues in edible tissues of slaughter animals. To simulate field conditions, broiler chicks were exposed to a total of 0.5 mg ochratoxin A per week for each of 4 weeks. Plasma toxin levels and tissue residues were measured by high-performance liquid chromatography (HPLC) and microplate enzyme-linked immunosorbent assay (ELISA). Results indicate an accumulation in plasma and wide distribution into all organs, with high levels in the liver and the kidney. Microscopical changes that could primarily be associated with toxin exposure were glomerulonephrosis, tubulonephrosis, focal tubular epithelial cell proliferation and multiple, adenoma-like structures in the renal parenchyma. The HPLC and ELISA methods gave similar results for both tissue distribution and depletion. Differences in absolute tissue toxin concentrations obtained by the two methods might be attributed to the different extraction and clean-up procedures, along with antibody specificity. The findings indicate that the dose applied causes subclinical tissue lesions and measurable tissue residues. PMID:12396358

  3. Analysis of saccharides in beverages by HPLC with direct UV detection.

    PubMed

    Schmid, Thomas; Baumann, Benedikt; Himmelsbach, Markus; Klampfl, Christian W; Buchberger, Wolfgang

    2016-03-01

    The present study demonstrates the suitability of direct UV detection for saccharide analysis in HPLC. Under highly alkaline conditions, the non-UV absorbing saccharides are converted by a photo-initiated chemical reaction in the detection cell into malonenolate, which can be detected at 266 nm. A straightforward method for such direct UV detection of saccharides after their separation by anion-exchange chromatography was developed and successfully applied to several beverage samples. Investigation and optimization of the influencing factors using design of experiment resulted in a baseline separation of glucose, fructose, and sucrose within 6 min and LOD values below 0.2 mg L(-1). In addition, a fast, simple and cost-effective flow injection method was developed to estimate the total saccharide concentration. The results of this method applied to beverage samples are in good agreement with the chromatographic method as well as to the saccharide concentration stated by the manufacturer. Finally, a comparison of different commercially available UV detectors and detector cells revealed that sensitive detection requires the use of recently introduced flow cells with extended path length. Graphical Abstract Online direct UV detection of saccharides in HPLC, which is possible due to a photo-initiated conversion of the saccharides into malonenolate. PMID:26780708

  4. Measurement of Microcystin -LR in Water Samples Using Improved HPLC Method

    PubMed Central

    Shamsollahi, Hamid Reza; Alimohammadi, Mahmood; Nabizadeh, Ramin; Nazmara, Shahrokh; Mahvi, Amir Hossein

    2015-01-01

    Microcystins are a group of toxic compounds produced by freshwater cyanobacteria and cause diseases. World Health Organization has recommended a concentration of 1 µg/l for Microcystin-LR (MC-LR) in potable water as guideline value. The high performance liquid chromatography (HPLC) followed by C18 analytical column and ultra violet detector for detection of MC-LR. In this regard, 5 different concentrations of MC-LR solutions were injected into HPLC. MC-LR was detected in 5.33 minute retention time and Calibration curve was achieved with R2=0.988. Detection limit for this method was obtained by using acetonitrile solutions (32% and 55%) as a gradient run and a high silanol activity column equal to 0.02 µg/mL. Despite no acidic organic modifier being used in the mixture of solvents, the sensitivity of this method was appropriate for detection of MC-LR. Because of short retention time, reduction in number of solvents and high resolution and suitable sensitivity, this method is affordable and is fast for detection and determination of MC-LR in potable water. PMID:25716387

  5. An HPLC-ECD method for monoamines and metabolites quantification in cuttlefish (cephalopod) brain tissue.

    PubMed

    Bidel, Flavie; Corvaisier, Sophie; Jozet-Alves, Christelle; Pottier, Ivannah; Dauphin, François; Naud, Nadège; Bellanger, Cécile

    2016-08-01

    The cuttlefish belongs to the mollusk class Cephalopoda, considered as the most advanced marine invertebrates and thus widely used as models to study the biology of complex behaviors and cognition, as well as their related neurochemical mechanisms. Surprisingly, methods to quantify the biogenic monoamines and their metabolites in cuttlefish brain remain sparse and measure a limited number of analytes. This work aims to validate an HPLC-ECD method for the simultaneous quantification of dopamine, serotonin, norepinephrine and their main metabolites in cuttlefish brain. In comparison and in order to develop a method suitable to answer both ecological and biomedical questions, the validation was also carried out on a phylogenetically remote species: mouse (mammals). The method was shown to be accurate, precise, selective, repeatable and sensitive over a wide range of concentrations for 5-hydroxyindole-3-acetic acid, serotonin, dopamine, 3,4-dihydroxyphenylacetic acid and norepinephrine in the both extracts of cuttlefish and mouse brain, though with low precision and recovery for 4-hydroxy-3-methoxyphenylethylene glycol. Homovanillic acid, accurately studied in rodents, was not detectable in the brain of cuttlefish. Overall, we described here the first fully validated HPLC method for the routine measurement of both monoamines and metabolites in cuttlefish brain. Copyright © 2016 John Wiley & Sons, Ltd. PMID:26613377

  6. Simultaneous determination of cortisol, cortisone, 6β-hydroxycortisol and 6β-hydroxycortisone by HPLC.

    PubMed

    Zheng, Liyun; Luo, Xi; Zhu, Lijun; Xie, Wenzhao; Liu, Shikun; Cheng, Zeneng

    2015-04-01

    A specific and sensitive method based on high-performance liquid chromatography with ultraviolet absorbance detection (HPLC-UV) was developed for the simultaneous determination of urinary cortisol (F), cortisone (E), 6β-hydroxycortisol (6β-OHF) and 6β-hydroxycortisone (6β-OHE) using dexamethasone as the internal standard. The method involved solid-phase extraction of the five compounds from urine using Oasis HLB Waters cartridges with an elution solvent of ethyl acetate-diethyl ether (5 mL; 4:1, v/v), followed by 1 mol/L of NaOH (1 mL) and 1.0% acetic acid (1 mL). Separation of the five analytes was achieved within 31 min by using a reversed-phase C18 analytical column (200 × 4.6 mm, 5 µm, Agilent). A UV detector operated at 245 nm was used. According to the method validation, inter-run and intra-run precision was below 9.45% and accuracy ranged from 98.16 to 115.50%. The lower limits of quantitation were 5 ng/mL for four analytes. This is the first HPLC method that can simultaneously determine F, E, 6β-OHF and 6β-OHE in human urine. The assay was applied to research the ratio of (6β-OHF + 6β-OHE)/(F + E) as a non-invasive biomarker for the metabolism of tacrolimus. PMID:25628347

  7. HPLC analysis of isoflavonoids and other phenolic agents from foods and from human fluids.

    PubMed

    Franke, A A; Custer, L J; Wang, W; Shi, C Y

    1998-03-01

    A fast, precise and selective diode array HPLC method is presented for the extraction and analysis of soy isoflavonoids from foods and from human urine, plasma, and breast milk in support of mechanistic and epidemiologic studies assessing the potential cancer protective role of soya or isoflavones. Solid phase or solvent extraction was chosen for isolation, and enzymatic or acid hydrolysis procedures were used for aglycone production depending on the matrix to be analyzed. C-18 reversed-phase HPLC was applied to selectively separate and quantitate daidzein (1), glycitein (3), and genistein (4), including their malonyl (a) and acetyl (b) esters, and their mammalian metabolites equol (6) and O-desmethylangolensin (7), as well as formononetin (2), biochanin-A (5), and coumestrol (8) using a gradient elution system. UV absorbance scans and authentic standards were applied for identification purposes, additional to fluorometric monitoring, electrochemical detection, and GC/ MS analysis after trimethyl silylation. Detection limits of 20-microl injections were found to be 1.09, 0.53, 3.28, and 1.00 pmoles for daidzein, genistein, equol, and O-desmethylangolensin (DMA), respectively, by monitoring at the individual compound's absorption maximum. The proposed method was applied to monitor isoflavone levels in soy foods and in human plasma, urine and breast milk after challenge with roasted soybeans. Implications of the presented results on the potential activity of isoflavones to prevent cancer by exposing newborn infants to these agents are discussed. PMID:9492334

  8. Identification and determination of flavonoids, carotenoids and chlorophyll concentration in Cynodon dactylon (L.) by HPLC analysis.

    PubMed

    Muthukrishnan, Saradha Devi; Kaliyaperumal, Ashokkumar; Subramaniyan, Annapoorani

    2015-01-01

    Cynodon dactylon (L.) is a potent medicinal plant in the traditional and current Indian medicinal systems. The objective of this research was to find out the levels of flavonoids, carotenoids and chlorophyll b in C. dactylon leaves by high-performance liquid chromatography (HPLC) equipped with a diode array detector. HPLC analysis revealed that total carotenoid and total flavonoid concentration were 62 mg/100 g and 249.1 μg/g, respectively. The mean chlorophyll b was 85.1 mg/100 g in C. dactylon. Among the flavonoids, quercetin (164.7 μg/g) was the major flavonoid followed by kaempferol (48.2 μg/g), rutin (18.4 μg/g), catechin (12.1 μg/g) and myricetin (5.7 μg/g). Of the carotenoids, β-carotene (35.2 mg/100 g) was predominant followed by lutein (17.0 mg/100 g), violaxanthin (5.8 mg/100 g) and zeaxanthin (4.2 mg/100 g). Chlorophyll b concentration was 85.1 mg/100 g in C. dactylon. The results of this investigation should be useful information for further pharmacological studies. PMID:25495959

  9. A gradient based facile HPLC method for simultaneous estimation of antioxidants extracted from tea powder.

    PubMed

    Nanjegowda, Shankara H; Papanna, Manasa G; Achar, Raghu Ram; Rangappa, Kanchugarakoppal S; Mallu, Puttaswamappa; Swamy, Shivananju Nanjunda

    2016-05-01

    A new simple, rapid and precise RP-HPLC method was developed for the extraction and quantitative estimation of caffeine (C), (-)-epigallocatechin gallate (EGCG), (+)-catechin(Ct), (-)-epicatechin(EC), and (-)-epicatechin gallate (ECG) (collectively named as Tea Powder Bioactives TPBAs) extracted from tea powder using different ratios of ethanol: water. The simultaneous determination of TPBAs was performed using the UV spectrophotometric method which employs the absorbance at 205 nm (λmax of caffeine and polyphenols). This method is a gradient based HPLC method with a flow rate of 0.8 mL/min using Inertsil ODS 100 × 4.6 mm, 3 μm column with methanol and ammonium dihydrogen phosphate (pH-2.8) as mobile phase. The method was validated in terms of specificity, precision, linearity, accuracy, limit of quantification (LOQ), and limit of detection (LOD). The linearity of the proposed method was investigated for concentration ranging between 0.5-60 μg/mL with regression co-efficient, R(2) = 0.999-1.0. This method estimates all the TPBAs simultaneously with enhanced precision and linearity as per the ICH guidelines. Also, to confirm the individual TPBA, the antioxidant property of the each TPBA was analyzed which was commensurate with that of the previous reports. PMID:27407191

  10. HPLC-Based Method to Evaluate Kinetics of Glucosinolate Hydrolysis by Sinapis alba Myrosinase1

    PubMed Central

    Vastenhout, Kayla J.; Tornberg, Ruthellen H.; Johnson, Amanda L.; Amolins, Michael W.; Mays, Jared R.

    2014-01-01

    Isothiocyanates (ITCs) are one of several hydrolysis products of glucosinolates, plant secondary metabolites which are substrates for the thioglucohydrolase myrosinase. Recent pursuits toward the development of synthetic, non-natural ITCs have consequently led to an exploration of generating these compounds from non-natural glucosinolate precursors. Evaluation of the myrosinase-dependent conversion of select non-natural glucosinolates to non-natural ITCs cannot be accomplished using established UV-Vis spectroscopic methods. To overcome this limitation, an alternative HPLC-based analytical approach was developed where initial reaction velocities were generated from non-linear reaction progress curves. Validation of this HPLC method was accomplished through parallel evaluation of three glucosinolates with UV-Vis methodology. The results of this study demonstrate that kinetic data is consistent between both analytical methods and that the tested glucosinolates respond similarly to both Michaelis–Menten and specific activity analyses. Consequently, this work resulted in the complete kinetic characterization of three glucosinolates with Sinapis alba myrosinase, with results that were consistent with previous reports. PMID:25068719

  11. Antioxidant, DNA protective efficacy and HPLC analysis of Annona muricata (soursop) extracts.

    PubMed

    George, V Cijo; Kumar, D R Naveen; Suresh, P K; Kumar, R Ashok

    2015-04-01

    Annona muricata is a naturally occurring edible plant with wide array of therapeutic potentials. In India, it has a long history of traditional use in treating various ailments. The present investigation was carried out to characterize the phytochemicals present in the methanolic and aqueous leaf extracts of A. muricata, followed by validation of its radical scavenging and DNA protection activities. The extracts were also analyzed for its total phenolic contents and subjected to HPLC analysis to determine its active metabolites. The radical scavenging activities were premeditated by various complementary assays (DRSA, FRAP and HRSA). Further, its DNA protection efficacy against H2O2 induced toxicity was evaluated using pBR322 plasmid DNA. The results revealed that the extracts were highly rich in various phytochemicals including luteolin, homoorientin, tangeretin, quercetin, daidzein, epicatechin gallate, emodin and coumaric acid. Both the extracts showed significant (p < 0.05) radical scavenging activities, while methanolic extract demonstrated improved protection against H2O2-induced DNA damage when compared to aqueous extract. A strong positive correlation was observed for the estimated total phenolic contents and radical scavenging potentials of the extracts. Further HPLC analysis of the phyto-constituents of the extracts provides a sound scientific basis for compound isolation. PMID:25829616

  12. Predicting surfactant modified soil/water distribution coefficients using micellar HPLC

    PubMed

    Paterson; Chowdhry; Leharne

    1999-01-01

    Soil water/distribution coefficients (Kd) have been measured for the partitioning of naphthalene, phenanthrene and pyrene between aqueous surfactant solutions and a clean soil. The surfactants used are ABA block copolymers constructed from ethylene oxide (the monomer used to synthesise the hydrophilic A blocks) and propylene oxide (used for the manufacture of the hydrophobic B block). Three of these surfactants comprising the same size propylene oxide block but different ethylene oxide/propylene oxide ratios were investigated. Increasing amounts of surfactant in the system result in a progressive decrease in the Kd values signifying an increasing tendency for the hydrophobic solutes to be dispersed in aqueous solution due to the action of the surfactant. More significantly for equal surfactant doses the most hydrophobic surfactant possessing the lowest ethylene oxide/propylene oxide ratio reduces Kd by the greatest amount whereas the most hydrophilic surfactant reduces Kd the least. Finally micellar HPLC using the above surfactants and hydrophobic solutes was undertaken. Interpolated capacity factors evaluated for particular surfactant doses correlated well with Kd values calculated for the same surfactant doses. The relationship between Kd and capacity was found to be log-linear and the correlation line could be fitted to the data obtained for all three surfactants. It is therefore concluded that micellar HPLC may be used for preliminary evaluations of the effectiveness of particular surfactants proposed for contaminated soils restoration schemes. PMID:10901653

  13. 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. PMID:27165575

  14. Quantitative analysis of citric acid/sodium hypophosphite modified cotton by HPLC and conductometric titration.

    PubMed

    Ye, Tao; Wang, Bijia; Liu, Jian; Chen, Jiangang; Yang, Yiqi

    2015-05-01

    Isocratic HPLC was used in conjunction with conductometric titration to quantitatively examine the modification of cotton cellulose by citric acid (CA)/sodium hypophosphite (SHP). CA/SHP had been extensively used as a green crosslinking agent for enhancement of cellulose and other carbohydrate polymers without in-depth understanding of the mechanisms. The current study investigated all identifiable secondary polycarboxylic acids from CA decomposition in the CA/SHP-cellulose system under various curing conditions. It was found that CA decomposition was more sensitive to temperature compared with the desirable esterification reaction. Two crosslinking mechanisms, namely ester crosslinking and SHP crosslinking were responsible for the observed improvement in crease resistance of CA/SHP treated cotton fabrics. An oligomer of citraconic acid (CCA) and/or itaconic acid (IA) was identified as a possible contributor to fabric yellowing. Finally, the crease resistance of fabrics correlated strongly with CA preservation in polyol-added CA/SHP crosslinking systems. The dosage of polyol should be held below an inflexion point to keep the undesirable competition against cellulose minimum. The combination of HPLC and conductometric titration was demonstrated to be useful in studying the CA/SHP-cellulose crosslinking system. The findings have implications for better application of CA/SHP in polysaccharide modifications in general. PMID:25659676

  15. Determination of arsenic species and arsenosugars in marine samples by HPLC-ICP-MS.

    PubMed

    Hirata, Shizuko; Toshimitsu, Hideki

    2005-10-01

    Arsenic-speciation analysis in marine samples was performed by high-pressure liquid chromatography (HPLC) with ICP-MS detection. Separation of eight arsenic species--As(III), MMA, DMA, As(V), AB, TMAO, AC and TeMAs(+)--was achieved on a C(18) column with isocratic elution (pH 3.0), under which conditions As(III) and MMA co-eluted. The entire separation was accomplished in 15 min. The HPLC-ICP-MS detection limits for the eight arsenic species were in the range 0.03-0.23 microg L(-1) based on 3 sigma for the blank response (n=5). The precision was calculated to be 2.4-8.0% (RSD) for the eight species. The method was successfully applied to several marine samples, e.g. oysters, fish, shrimps, and marine algae. Low-power microwave digestion was employed for extraction of arsenic from seafood products; ultrasonic extraction was employed for the extraction of arsenic from seaweeds. Separation of arsenosugars was achieved on an anion-exchange column. Concentrations of arsenosugars 2, 3, and 4 in marine algae were in the range 0.18-9.59 microg g(-1). PMID:16132126

  16. Determination of arsenic species in marine samples by HPLC-ICP-MS.

    PubMed

    Hirata, Shizuko; Toshimitsu, Hideki; Aihara, Masato

    2006-01-01

    Arsenic speciation analysis in marine samples was performed using high performance liquid chromatography (HPLC) with ICP-MS detection. The separation of eight arsenic species viz. arsenite (As(III)), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsenate (As(V)), arsenobetaine, trimethylarsine oxide (TMAO), arsenocholine and tetramethylarsonium ion (TeMAs) was achieved on a Shiseido Capcell Pak C18 column by using an isocratic eluent (pH 3.0), in which condition As(III) and MMA were co-eluted. The entire separation was accomplished in 15 min. The detection limits for 8 arsenic species by HPLC/ICP-MS were in the range of 0.02 - 0.10 microg L(-1) based on 3sigma of blank response (n=9). The precision was calculated to be 3.1-7.3% (RSD) for all eight species. The method then successfully applied to several marine samples e.g., oyster, scallop, fish, and shrimps. For the extraction of arsenic species from seafood products, the low power microwave digestion was employed. The extraction efficiency was in the range of 52.9 - 112.3%. Total arsenic concentrations were analyzed by using the microwave acid digestion. The total arsenics in the certified reference materials (DORM-2 and TORT-2) were analyzed and agreed with the certified values. The concentrations of arsenics in marine samples were in the range 6.6 - 35.1 microg g(-1). PMID:16429770

  17. A global seasonal surface ocean climatology of phytoplankton types based on CHEMTAX analysis of HPLC pigments

    NASA Astrophysics Data System (ADS)

    Swan, Chantal M.; Vogt, Meike; Gruber, Nicolas; Laufkoetter, Charlotte

    2016-03-01

    Much advancement has been made in recent years in field data assimilation, remote sensing and ecosystem modeling, yet our global view of phytoplankton biogeography beyond chlorophyll biomass is still a cursory taxonomic picture with vast areas of the open ocean requiring field validations. High performance liquid chromatography (HPLC) pigment data combined with inverse methods offer an advantage over many other phytoplankton quantification measures by way of providing an immediate perspective of the whole phytoplankton community in a sample as a function of chlorophyll biomass. Historically, such chemotaxonomic analysis has been conducted mainly at local spatial and temporal scales in the ocean. Here, we apply a widely tested inverse approach, CHEMTAX, to a global climatology of pigment observations from HPLC. This study marks the first systematic and objective global application of CHEMTAX, yielding a seasonal climatology comprised of ~1500 1°×1° global grid points of the major phytoplankton pigment types in the ocean characterizing cyanobacteria, haptophytes, chlorophytes, cryptophytes, dinoflagellates, and diatoms, with results validated against prior regional studies where possible. Key findings from this new global view of specific phytoplankton abundances from pigments are a) the large global proportion of marine haptophytes (comprising 32±5% of total chlorophyll), whose biogeochemical functional roles are relatively unknown, and b) the contrasting spatial scales of complexity in global community structure that can be explained in part by regional oceanographic conditions. The results are publically accessible via

  18. HPLC Determination of Esculin and Esculetin in Rat Plasma for Pharmacokinetic Studies.

    PubMed

    Rehman, Shaheed Ur; Kim, In Sook; Kang, Ki Sung; Yoo, Hye Hyun

    2015-09-01

    An optimized, sensitive and validated reversed-phase high-performance liquid chromatography (RP-HPLC) method with UV detection is described for simultaneous determination of esculin and its aglycone, esculetin, in rat plasma. After addition of internal standard (chrysin), plasma samples were pretreated by solid-phase extraction and introduced into the HPLC system. Analytes were separated on a RP C18 column with a mobile phase of 0.075% acetic acid in water (solvent A) and 90% acetonitrile in solvent A (solvent B) using gradient elution at a flow rate of 1.0 mL/min. The wavelength for UV detection was set at 338 nm. Calibration curves for esculin and esculetin were constructed over a range of 10-1,000 ng/mL. The developed method was found to be specific, precise and accurate. The method was successfully applied to study the pharmacokinetics of esculin and esculetin in rats. After oral administration of 120 mg/kg, the mean Cmax values were 340.3 and 316.5 ng/mL and the AUClast values were 377.3 and 1276.5 h ng/mL for esculin and esculetin, respectively. The bioavailability of esculin was calculated to be 0.62%. PMID:25713108

  19. A Simple HPLC-UV Method for the Determination of Glutathione in PC-12 Cells.

    PubMed

    Appala, Raju N; Chigurupati, Sridevi; Appala, Raju V V S S; Krishnan Selvarajan, Kesavanarayanan; Islam Mohammad, Jahidul

    2016-01-01

    A highly sensitive and simple HPLC-UV method was developed and validated for the assay of glutathione (GSH) in PC-12 cells. Glutathione is a major intracellular antioxidant having multiple biological effects, best known for its cytoprotective effects against cell damage from reactive oxygen species and toxic reactive metabolites and regulating the cellular redox homeostasis. Due to its own sulfhydryl (SH) group, GSH readily reacts with Ellman's reagent to form a stable dimer which allows for quantitative estimation of GSH in biological systems by UV detection. The separation was achieved using a C8 column with a mobile phase consisting of phosphate buffer adjusted to pH 2.5 (mobile phase A) and acetonitrile (mobile phase B), running in a segmented gradient manner at a flow rate of 0.8 mL/min, and UV detection was performed at 280 nm. The developed HPLC-UV method was validated with respect to precision, accuracy, robustness, and linearity within a range of 1-20 μg/mL. Limit of detection (LOD) and limit of quantification (LOQ) were 0.05 and 0.1 μg/mL, respectively. Furthermore, the method shows the applicability for monitoring the oxidative stress in PC-12 cells. PMID:27127683

  20. HPLC/Fluorometric Detection of Carvedilol in Real Human Plasma Samples Using Liquid-Liquid Extraction.

    PubMed

    Yilmaz, Bilal; Arslan, Sakir

    2016-03-01

    A simple, rapid and sensitive high-performance liquid chromatography (HPLC) method has been developed to quantify carvedilol in human plasma using an isocratic system with fluorescence detection. The method included a single-step liquid-liquid extraction with diethylether and ethylacetate mixture (3 : 1, v/v). HPLC separation was carried out by reversed-phase chromatography with a mobile phase composed of 20 mM phosphate buffer (pH 7)-acetonitrile (65 : 35, v/v), pumped at a flow rate of 1.0 mL/min. Fluorescence detection was performed at 240 nm (excitation) and 330 nm (emission). The calibration curve for carvedilol was linear from 10 to 250 ng/mL. Intra- and interday precision values for carvedilol in human plasma were <4.93%, and accuracy (relative error) was better than 4.71%. The analytical recovery of carvedilol from human plasma averaged out to 91.8%. The limits of detection and quantification of carvedilol were 3.0 and 10 ng/mL, respectively. Also, the method was successfully applied to three patients with hypertension who had been given an oral tablet of 25 mg carvedilol. PMID:26538492

  1. Reverse-phase HPLC method for measuring polarity distributions of natural organic matter.

    PubMed

    Namjesnik-Dejanovic, Ksenija; Cabaniss, Stephen E

    2004-02-15

    A reverse-phase high-pressure liquid chromatography (RP-HPLC) method was developed to measure the polarity distribution of natural organic matter (NOM) samples. The polarity distribution is obtained by calibrating an octadecyl bonded silica phase column and polar eluent with compounds of known octanol-water partition coefficient (Kow) and using this calibration curve to transform NOM retention times into an equivalent Kow. Polarity distributions treat the NOM samples as a complex mixture rather than summarizing the polarity in a single number. The method is sensitive, with UV detection allowing quantitation of samples with <5 mg of C/L. Individual chromatograms are acquired in <20 min, allowing much faster analysis on smaller samples than XAD resin separation or 13C NMR. Polarity distributions of 10 representative NOM isolates and 2 whole water samples indicate that NOM is generally hydrophilic in nature (log Kow < 2), although XAD-8 isolates are more hydrophobic than RO isolates from the same source. Hydrophilicity, as indicated by recovery from the HPLC column, is correlated to the elemental oxygen/carbon ratio but does not correlate strongly with molecular weight or 13C NMR aromaticity. PMID:14998025

  2. 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.

  3. HPLC Analysis, Optimization of Extraction Conditions and Biological Evaluation of Corylopsis coreana Uyeki Flos.

    PubMed

    Seo, Ji-Hye; Kim, Jung-Eun; Shim, Jung-Hyun; Yoon, Goo; Bang, Mi-Ae; Bae, Chun-Sik; Lee, Kyung-Jin; Park, Dae-Hun; Cho, Seung-Sik

    2016-01-01

    A method for the separation and quantification of three flavonoids and one isocoumarin by reverse-phase high performance liquid chromatography (HPLC) has been developed and validated. Four constituents present in a crude ethanolic extract of the flowers of Coryloposis coreana Uyeki, were analyzed. Bergenin, quercetin, quercitrin and isosalipurposide were used as calibration standards. In the present study, an excellent linearity was obtained with an r² higher than 0.999. The chromatographic peaks showed good resolution. In combination with other validation data, including precision, specificity, and accuracy, this method demonstrated good reliability and sensitivity, and can be conveniently used for the quantification of bergenin, quercetin, quercitrin and isosalipurposide in the crude ethanolic extract of C. coreana Uyeki flos. Furthermore, the plant extracts were analyzed with HPLC to determine the four constituents and compositional differences in the extracts obtained under different extraction conditions. Several extracts of them which was dependent on the ethanol percentage of solvent were also analyzed for their antimicrobial and antioxidant activities. One hundred % ethanolic extract from C. coreana Uyeki flos showed the best antimicrobial activity against the methicillin-resistant Staphylococcus aureus (MRSA) strain. Eighty % ethanolic extract showed the best antioxidant activity and phenolic content. Taken of all, these results suggest that the flower of C. coreana Uyeki flos may be a useful source for the cure and/or prevention of septic arthritis, and the validated method was useful for the quality control of C. coreana Uyeki. PMID:26784157

  4. HPLC analysis of polyphenols in the fruits of Rubus idaeus L. (Rosaceae).

    PubMed

    Sparzak, B; Merino-Arevalo, M; Vander Heyden, Y; Krauze-Baranowska, M; Majdan, M; Fecka, I; Głód, D; Bączek, T

    2010-11-01

    The separation of anthocyanins present in the fruits of 11 varieties of red raspberries (Rubus idaeus L.) was performed by high performance liquid chromatography (HPLC) with a diode-array detector and evaporative light scattering detection (ELSD). The ELSD parameters--drift tube temperature, nebulising gas flow rate and gain value--were optimised to get the best detection and identification of the anthocyanins. The varieties Heritage and Willamette had the simplest anthocyanin sets consisting of only two predominant anthocyanins--cyanidin-3-O-sophoroside (1) and cyanidin-3-O-glucoside (3), while in the other varieties two other predominant compounds were also present, cyanidin-3-O-rutinoside (4) and cyanidin-3-O-(2(G)-O-glucosylrutinoside) (2). Moreover, using ELSD, simultaneous analysis of anthocyanins and sanguiin H-6 (5), an ellagitannin, was performed. The contents of anthocyanins and sanguiin H-6 (5) were estimated by HPLC with ultraviolet-visible (UV-vis) light detection. The determined concentrations of anthocyanins varied from 76.22 to 277.06 mg per 100 g of dry weight (d.w.). The content of sanguiin H-6 (5) was in the range from 135.04 to 547.48 mg per 100 g of d.w. PMID:21104526

  5. RP-HPLC analysis of flucloxacillin in human plasma: validation and application to a bioequivalence study.

    PubMed

    Zhou, Q; Ruan, Z; Yuan, H; Jiang, B; Xu, D

    2007-02-01

    A RP-HPLC method with rapid sample processing was developed for quantitation of flucloxacillin in human plasma using dicloxacillin as the internal standard. The plasma sample (100 microL) was acidified with glacial acetic acid, and deproteinized by precipitation with acetonitrile. The supernatant was directly injected into the HPLC system. Separation was achieved on an Alltima C18 column (250 mmx4.6 mm I.D., 5 microm), with a mixture of 10 mmol x L(-1) KH2PO4-acetonitrile (64.5:35.5, v/v) as mobile phase. The assay was successfully applied to a randomized, two-period cross-over bioequivalence study in 20 healthy Chinese volunteers following a single oral dose of 250 mg flucloxacillin capsules. A non-compartmental method was used for pharmacokinetic analysis. Compared with data in the literature, flucloxacillin was eliminated more slowly in Chinese than in Caucasians. Cmax, AUC(0-t) and AUC(0-infinity) were tested for bioequivalence after log-transformation of data. No significant difference was found. Tmax was analyzed by Wilcoxon's test and no significant difference was obtained (P > 0.05). Based on these statistical inferences, the two formulations were judged to be bioequivalent and, thus, can be prescribed interchangeably. PMID:17341027

  6. Direct UV Spectrophotometry and HPLC Determination of Triton X-100 in Split Virus Influenza Vaccine.

    PubMed

    Pavlović, Bojana; Cvijetić, Nataša; Dragačević, Luka; Ivković, Branka; Vujić, Zorica; Kuntić, Vesna

    2016-03-01

    One of the most commonly used surfactants in the production of split virus influenza vaccine is nonionic surfactant Triton X-100. After splitting of the virus is accomplished, Triton X-100 is removed from the vaccine by subsequent production steps. Because of toxicity of Triton X-100, which remains in the vaccine in residual amounts, a sufficiently sensitive method for its detection and quantification needs to be defined. Two methods for determination of Triton X-100 residuals were developed: the UV-spectrophotometry and HPLC methods. For both methods, preparation of vaccine samples and removal of proteins and virus particles were crucial: samples were treated with methanol (1:1) and then centrifuged at 25 000 × g for 30 min. After such treatment, the majority of vaccine components that interfered in the UV region were removed, and diluted samples could be directly measured. The chromatographic system included C18 column, step methanol gradient, and detection at 225 nm with a single peak of Triton X-100 at 12.6 min. Both methods were validated and gave satisfactory results for accuracy, precision, specificity, linearity, and robustness. LOQ was slightly lower for the HPLC method. Hence, it was shown that both methods are suitable for analysis of residual amounts of Triton X-100, with the advantages of the UV method being its simplicity and availability in most laboratories. PMID:26960682

  7. HPLC method development, validation, and impurity characterization of a potent antitumor indenoisoquinoline, LMP776 (NSC 725776).

    PubMed

    Wang, Jennie; Liu, Mingtao; Yang, Chun; Wu, Xiaogang; Wang, Euphemia; Liu, Paul

    2016-05-30

    An HPLC method for the assay of a DNA topoisomerase inhibitor, LMP776 (NSC 725776), has been developed and validated. The stress testing of LMP776 was carried out in accordance with International Conference on Harmonization (ICH) guidelines Q1A (R2) under acidic, alkaline, oxidative, thermolytic, and photolytic conditions. The separation of LMP776 from its impurities and degradation products was achieved within 40 min on a Supelco Discovery HS F5 column (150 mm × 4.6 mm i.d., 5 μm) with a gradient mobile phase comprising 38-80% acetonitrile in water, with 0.1% trifluoroacetic acid in both phases. LC/MS was used to obtain mass data for characterization of impurities and degradation products. One major impurity was isolated through chloroform extraction and identified by NMR. The proposed HPLC assay method was validated for specificity, linearity (concentration range 0.25-0.75 mg/mL, r = 0.9999), accuracy (recovery 98.6-100.4%), precision (RSD ≤ 1.4%), and sensitivity (LOD 0.13 μg/mL). The validated method was used in the stability study of the LMP776 drug substance in conformance with the ICH Q1A (R2) guideline. PMID:26970596

  8. HPLC study on the stability of bendamustine hydrochloride immobilized onto polyphosphoesters.

    PubMed

    Pencheva, Ivanka; Bogomilova, Anita; Koseva, Neli; Obreshkova, Danka; Troev, Kolio

    2008-12-01

    Novel water soluble polymer complexes of bendamustine hydrochloride, a bifunctional alkylating agent with antimetabolic and cytotoxic activity, were developed using biodegradable polymer carriers-poly(oxyethylene H-phosphonate), poly(methyloxyethylene phosphate) and poly(hydroxyoxyethylene phosphate). Bendamustine hydrochloride was immobilized onto polyphosphoesters via covalent, ionic and hydrogen bonding. The structure of the complexes formed was elucidated by (1)H, (13)C, (31)P NMR and FT-IR spectroscopy. The chemical stability of bendamustine hydrochloride in the novel complexes was studied by HPLC analysis based on a validated method with appointed analytical parameters such as specificity, repeatability, limit of quantitation, limit of detection and linearity. The results from the HPLC indicate that in neutral (pH 7) and alkaline (pH 9) media bendamustine hydrochloride in the polymer complexes is more stable than the pure bendamustine hydrochloride. The enhanced stability of the immobilized drug is explained with the drug interaction with the polymer carriers or their degradation products. PMID:18926656

  9. Simultaneous determination of prenylflavonoid and hop bitter acid in beer lee by HPLC-DAD-MS.

    PubMed

    Kao, T H; Wu, G Y

    2013-11-15

    An HPLC-DAD-MS method with high accuracy and precision was developed for determination of prenylflavonoids and hop bitter acids in beer lee, a by-product from beer brewing process. Four prenylflavonoids and nine hop bitter acids can be simultaneously separated in 29 min using a Thermo HyPURITY C18 column in combination with diode array dectector and mass spectrometer with HPLC solvent gradient system of phosphoric acid aqueous solution at pH 1.6 and acetonitrile at a flow rate of 1.5 mL/min and detection wavelength at 314 nm. Beer lee is found to contain isoxanthohumol (36.2 μg/g), xanthohumol (29.6 μg/g), 8-prenylnaringenin (7.84 μg/g), 6-prenylnaringenin (19.2 μg/g), cohumulone (44.7 μg/g), humulone (123 μg/g), adhumulone (21.8 μg/g), colupulone (44.2 μg/g), lupulone (33.2 μg/g), and adlupulone (5.76 μg/g). PMID:23790907

  10. HPLC analysis of discrete haptoglobin isoform N-linked oligosaccharides following 2D-PAGE isolation.

    PubMed

    He, Zhicong; Aristoteli, Lina P; Kritharides, Leonard; Garner, Brett

    2006-05-01

    Glycosylation is a common but variable modification that regulates glycoprotein structure and function. We combined small format 2D-PAGE with HPLC to analyse discrete human haptoglobin isoform N-glycans. Seven major and several minor haptoglobin isoforms were detected by 2D-PAGE. N-Glycans released from Coomassie-stained gel spots using PNGase were labeled at their reducing termini with 2-aminobenzamide. HPLC analysis of selected major isoform N-glycans indicated that sialic acid composition determined their separation by isoelectric focussing. N-Glycans from two doublets of quantitatively minor isoforms were also analysed. Although separation of each pair of doublets was influenced by sialylation, individual spots within each doublet contained identical N-glycans. Thus, heterogeneity in minor haptoglobin isoforms was due to modifications distinct from N-glycan structure. These studies describe a simple method for analysing low abundance protein N-glycans and provide details of discrete haptoglobin isoform N-glycan structures which will be useful in proteomic analysis of human plasma samples. PMID:16546121

  11. Application of Statistical Thermodynamics To Predict the Adsorption Properties of Polypeptides in Reversed-Phase HPLC.

    PubMed

    Tarasova, Irina A; Goloborodko, Anton A; Perlova, Tatyana Y; Pridatchenko, Marina L; Gorshkov, Alexander V; Evreinov, Victor V; Ivanov, Alexander R; Gorshkov, Mikhail V

    2015-07-01

    The theory of critical chromatography for biomacromolecules (BioLCCC) describes polypeptide retention in reversed-phase HPLC using the basic principles of statistical thermodynamics. However, whether this theory correctly depicts a variety of empirical observations and laws introduced for peptide chromatography over the last decades remains to be determined. In this study, by comparing theoretical results with experimental data, we demonstrate that the BioLCCC: (1) fits the empirical dependence of the polypeptide retention on the amino acid sequence length with R(2) > 0.99 and allows in silico determination of the linear regression coefficients of the log-length correction in the additive model for arbitrary sequences and lengths and (2) predicts the distribution coefficients of polypeptides with an accuracy from 0.98 to 0.99 R(2). The latter enables direct calculation of the retention factors for given solvent compositions and modeling of the migration dynamics of polypeptides separated under isocratic or gradient conditions. The obtained results demonstrate that the suggested theory correctly relates the main aspects of polypeptide separation in reversed-phase HPLC. PMID:26023813

  12. Stability-indicating HPLC method for the determination of impurities in meprobamate with refractive index detection.

    PubMed

    Karthikeyan, K; Balaji, T S; Shanmugasundaram, P; Chandrasekara Pillai, K

    2010-03-01

    The purpose of this study is to develop and validate a simple, sensitive, and robust high-performance liquid chromagraphic (HPLC) method for the determination of impurities ca. 2-methyl-2-propyl-1,3-propane diol (MP0) and 2-hydroxymethyl-2-methyl pentyl carbamate (MP1) in meprobamate (MEP) drug substance with refractive index (RI) detection. This method utilizes a Zorbax Eclipse XDB C(18) HPLC column, a mobile phase of 80:20 (v/v) 10 mM KH(2)PO(4),-acetonitrile, respectively. The stability-indicating capability of the method has been established by performing stress studies under acidic, basic, oxidation, light, humidity, and thermal conditions. The major degradation products of acid and base hydrolysis are identified as MP0 and MP1. The recovery data obtained for impurities are between 96.0-109.8%. The detection and quantitation limits of this method ranges from 0.009 to 0.017 mg/mL and 0.029 to 0.055 mg/mL, respectively. The relative standard deviation (RSD) for the area at QL is less than 6.1%. Good linearity (r(2) > 0.99) and precision (RSD < 2.2%) have been obtained for MEP, MP0, and MP1. This method has been applied successfully to determine the content of impurities in MEP bulk drug. PMID:20223088

  13. Aflatoxin B1 in eggs and chicken livers by dispersive liquid-liquid microextraction and HPLC.

    PubMed

    Amirkhizi, Behzad; Arefhosseini, Seyed Rafie; Ansarin, Masoud; Nemati, Mahboob

    2015-01-01

    A rapid, low-cost and simple technique has been developed for the determination of aflatoxin B1 (AFB1) in eggs and livers using high-performance liquid chromatography (HPLC) with UV detection. In this study, the presence of AFB1 was investigated in 150 eggs and 50 chicken livers from the local market of Tabriz, Iran. AFB1 was extracted with a mixture of acetonitrile:water (80:20) and cleaned up by dispersive liquid-liquid microextraction which is a very economical, fast and sensitive method. AFB1 was quantified by HPLC-UV without need for any complex derivatisation in samples to enhance the detection. The results showed that 72% of the liver and 58% of the egg samples were contaminated with AFB1 ranging from 0.30 to 16.36 µg kg (̶1). limit of detection and limit of quantification for AFB1 were 0.08 and 0.28 µg kg (̶ 1), respectively. The proposed method is suitable for fast analysing of AFB1 in egg and liver samples. PMID:26160230

  14. HPLC method validation for measurement of sulforaphane level in broccoli by-products.

    PubMed

    Campas-Baypoli, O N; Sánchez-Machado, D I; Bueno-Solano, C; Ramírez-Wong, B; López-Cervantes, J

    2010-04-01

    A simple and specific analytical method was developed and tested for the determination of sulforaphane in broccoli by-products. The method includes the optimization of the conversion of glucoraphanin to sulforaphane, followed by purification of extracts using solid-phase extraction and high-performance liquid chromatography (HPLC) analysis. The response surface methodology was used to find optimum conditions for the preparation and purification procedure. Chromatographic conditions for reversed-phase HPLC with UV photodiode array detection were as follows: column, Exil ODS C(18), 25 x 0.46 cm, 5 microm; column temperature, 36 degrees C; mobile phase, a 30 : 70 (v/v) mixture of acetonitrile:water; flow rate, 0.6 mL/min. The detection wavelength was UV 202 nm. Under these conditions, excellent linearity was obtained (r(2) = 1), and the overall recovery was 97.5 and 98.1% for fresh florets and lyophilized florets, respectively. The precision results showed that the relative standard deviation of the repeatability for florets fresh and lyophilized was 3.0 and 4.0%, respectively. Sulforaphane contents were determined in the edible portion of fresh broccoli, and broccoli crop remains. PMID:19650149

  15. Rapid determination of zearalenone in edible oils by HPLC with fluorescence detection.

    PubMed

    Majerus, Paul; Graf, Norbert; Krämer, Maria

    2009-10-01

    A fast, cost-efficient, sensitive and accurate assay method for zearalenone in edible oils is described, as an alternative to gel permeation chromatography (GPC). Oil samples were extracted with an alkaline mixture of methanol and water (methanol +10 g/l aqueous ammonium carbaminate solution, pH 9; 9 + 1, v+v). The pH of the extract was neutralized with hydrochloric acid and then concentrated to dryness. The residue was dissolved with HPLC solvent, and zearalenone was determined by high-performance liquid chromatography with fluorometric detection (HPLC-FLD). The method was successfully validated for two matrices, maize oil and rapeseed oil. The recovery rate was 87%, and the coefficient of variation was 2.8% in a rapeseed oil sample contaminated with 27 µg zearalenone/kg. At a signal-to-noise ratio of 3:1, the method detection limit was 10 µg/kg, which was considered to be adequate in view of the present European Union maximum level of 400 µg/kg. PMID:23605090

  16. Solicitation of HPLC and HPTLC Techniques for Determination of Rutin from Polyalthia longifolia Thwaites

    PubMed Central

    Doshi, Gaurav Mahesh; Zine, Sandeep Prabhakar; Chaskar, Pratip Kashinath; Une, Hemant Devidas

    2014-01-01

    Background: Polyalthia longifolia Thwaites is an important traditional plant in India. Rutin, an active constituent has been reported to possess good amount of pharmacological as well as therapeutic potential. Objective: The aim of the present study was to find out by analytical techniques how much percentage of rutin is present in the plant leaves’ ethanolic extract by analytical techniques. Materials and Methods: Shade dried leaves of Polyalthia longifolia were subjected to cold ethanolic extraction followed by monitoring the isolated rutin high-pressure liquid chromatography (HPLC) and high performance thin layer chromatography (HPTLC) after carrying out preliminary phytochemical screening. Results: Extraction yield was found to be 13.94% w/w. Phytochemical screening of the extract showed the presence of flavonoids, steroids, diterpenoids, alkaloids, saponins, tannins and phenolic compounds and mucilage. From the Rf value, the ethanolic extract was found to be having constituent identical to rutin. By HPTLC and HPLC the amount of rutin was found to be 11.60% w/w and 4.03% w/v, respectively. Conclusion: The active constituent isolated was found to be equal to rutin. PMID:25002804

  17. A Simple HPLC-UV Method for the Determination of Glutathione in PC-12 Cells

    PubMed Central

    Appala, Raju N.; Appala, Raju V. V. S. S.

    2016-01-01

    A highly sensitive and simple HPLC-UV method was developed and validated for the assay of glutathione (GSH) in PC-12 cells. Glutathione is a major intracellular antioxidant having multiple biological effects, best known for its cytoprotective effects against cell damage from reactive oxygen species and toxic reactive metabolites and regulating the cellular redox homeostasis. Due to its own sulfhydryl (SH) group, GSH readily reacts with Ellman's reagent to form a stable dimer which allows for quantitative estimation of GSH in biological systems by UV detection. The separation was achieved using a C8 column with a mobile phase consisting of phosphate buffer adjusted to pH 2.5 (mobile phase A) and acetonitrile (mobile phase B), running in a segmented gradient manner at a flow rate of 0.8 mL/min, and UV detection was performed at 280 nm. The developed HPLC-UV method was validated with respect to precision, accuracy, robustness, and linearity within a range of 1–20 μg/mL. Limit of detection (LOD) and limit of quantification (LOQ) were 0.05 and 0.1 μg/mL, respectively. Furthermore, the method shows the applicability for monitoring the oxidative stress in PC-12 cells. PMID:27127683

  18. Antioxidant capacity and phenolic compounds of Lonicerae macranthoides by HPLC-DAD-QTOF-MS/MS.

    PubMed

    Hu, Xin; Chen, Lin; Shi, Shuyun; Cai, Ping; Liang, Xuejuan; Zhang, Shuihan

    2016-05-30

    Lonicerae macranthoides with strong antioxidant activity is commonly used in traditional Chinese medicine and folk tea/beverage. However, detailed information about its antioxidant activity and bioactive compounds is limited. Then at first, we comparatively evaluated total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activities of water extract, petroleum ether, ethyl acetate and n-butanol fractions of L. macranthoides. Ethyl acetate fraction exhibited the highest level of TPC (207.38 mg GAE/g DW), TFC (53.06 mg RE/g DW) and the best DPPH scavenge activity and reducing power. n-Butanol fraction showed the best ABTS(+) and O2(-) scavenging activities. Interestingly, water extract, ethyl acetate and n-butanol fractions showed stronger antioxidant activities than positive control, butylated hydroxytoluene (BHT). After that, thirty-one antioxidant phenolic compounds, including twenty-two phenolic acids and nine flavonoids, were screened by DPPH-HPLC experiment and then identified using HPLC-DAD-QTOF-MS/MS. It is noted that twenty-one compounds (1, 3-4, 6-17, 19, 23, 26, 28-29, and 31), as far as was known, were discovered from L. macranthoide for the first time, and eleven of them (3-4, 10-17, and 23) were reported in Lonicera species for the first time. Results indicated that L. macranthoides could serve as promising source of rich antioxidants in foods, beverages and medicines for health promotion. PMID:26970594

  19. Study of lipophilicity and membrane partition of 4-hydroxycoumarins by HPLC and PCA.

    PubMed

    Ilijaš, Marina; Malnar, Ivica; Gabelica Marković, Vesna; Stepanić, Višnja

    2013-03-25

    Physicochemical properties provide reliable guidance in optimization of pharmacological efficiency and ADME profile of small chemical compounds. Their high-throughput determination is regularly based on application of HPLC techniques. In this study CHI and CHI IAM of 32 4-hydroxycoumarin analogs were measured by HPLC with methanol gradient at pHs 2.8 and 7.0. Results were analyzed by PCA in terms of computed descriptors in order to identify space for optimization of their phospholipids affinity and lipophilicity for which predictive software failed to produce reliable estimations. The chromatographic behavior of studied 4-hydroxycoumarins was typical of acidic compounds. The CHI(2.8), CHI(7.0), CHI IAM(2.8) and CHI IAM(7.0) values were all considerably cross-correlated in accordance with their prevailing lipophilic character. Structure-retention relationship (SRR) analysis furthermore revealed that H-bond accepting capacity and dipolar interactions with methanol generally shorten their retention times. However, deviations from the linear trends were noticed for R3/R5-substituted derivatives able to form intramolecular contacts with the 4-O(H) group and characterized by more uniform electron density at 2-O and 4-O atoms and quite different acidity/H-bond donating capacity than the rest of derivatives. Thus, CHI and CHI IAM determinations and SRR analysis are fast and efficiently pointed to ways of modifying biological activities of 4-hydroxycoumarins. PMID:23298913

  20. Synthesis of porous zirconia spheres for HPLC by polymerization-induced colloid aggregation (PICA)

    SciTech Connect

    Sun, L.; Annen, M.J.; Lorenzano-Porras, F.; Carr, P.W.; McCormick, A.V. )

    1994-03-15

    Porous, spherical zirconia particles with a narrow particle size distribution, which are useful as chromatographic packing materials for high performance liquid chromatography (HPLC), were synthesized by polymerization-induced colloid aggregation (PICA) first described by Iler and McQueston (US Patent 4,010,242, 1977.) and the effects of a number of crucial processing variables were examined. In this method, an aqueous zirconia sol consisting of 700 [angstrom] (mean diameter) particles is mixed with urea and formaldehyde polymer adsorbs onto the ZrO[sub 2] colloids, entraining the colloids in the precipitation of the polymer gel and thus alloying the colloids to aggregate. Features of the aggregation process are elucidated from responses of the process to variations in temperature, reaction mixture composition, and solvent polarity. Results suggest that the aggregation process resembles those reported for the bridging flocculation of colloids by adsorbed polymers. Porous zirconia particles obtained after polymer combustion and sintering of the aggregates are 3.5 [mu]m in diameter with a surface area of 13 m[sup 2]/g, a porosity of 29% and pores ranging from <50 to 350 [angstrom] in diameter. The particles are strong enough to withstand the packing of a HPLC column.

  1. Determination of microsomal lauric acid hydroxylase activity by HPLC with flow-through radiochemical quantitation

    SciTech Connect

    Romano, M.C.; Straub, K.M.; Yodis, L.A.P.; Eckardt, R.D.; Newton, J.F.

    1988-04-01

    An assay for the microsomal hydroxylation of lauric acid (LA), based on HPLC with flow-through radiochemical detection, has been developed. Conditions were optimized for resolution and quantitation of three microsomal metabolites of /sup 14/C-LA, one of which has not been reported previously as a metabolite of LA in mammalian microsomal incubations. These products, 12-(omega)-hydroxy-LA, 11-(omega-1)-hydroxy-LA, and a novel metabolite, 10-(omega-2)-hydroxy-LA, were isolated by HPLC and identified by gas chromatography/mass spectrometry. In the presence of NADPH, the formation of all three metabolites was linear with time and microsomal protein concentration. Hydrogen peroxide also supported the microsomal metabolism of LA, although the ratio of metabolites was substantially different than that produced by NADPH-supported microsomes. Several biochemical probes (metyrapone, ..cap alpha..-naphthoflavone, 2-diethylaminoethyl-2,2-diphenylvalerate hydrochloride, and 10-undecynoic acid) were used to dissociate the three LA hydroxylase activities. These experiments suggest that the site-specific hydroxylation (omega-, (omega-1), (omega-2)-) of LA may be catalyzed by different isozymes of cytochrome P-450.

  2. An enzymic assay for uric acid in serum and urine compared with HPLC.

    PubMed

    Dubois, H; Delvoux, B; Ehrhardt, V; Greiling, H

    1989-03-01

    We evaluated a colorimetric method for the assay of uric acid in serum or urine, which utilises a Trinder chromogenic system modified by the inclusion of 2,4,6-tribromo-3-hydroxybenzoic acid for oxidative coupling to p-aminophenazone. Colour development (Amax: 512 nm) is complete within five minutes. Measurement of a sample blank is not needed. The procedure involves pre-incubation with ascorbic acid oxidase and detergent to eliminate interference by ascorbic acid and to abolish turbidity due to lipaemia; this pretreatment was effective up to 1.14 mmol/l ascorbate and up to at least 25 mmol/l triacylglycerol. Interference by icteric sera was insignificant up to about 170 mumol/l bilirubin. The method is linear up to at least 1428 mumol/l. In human serum and urine the procedure correlates well with HPLC and the uricase p-aminophenazone method on the SMAC analyser. Within-run and between-run imprecisions of the enzymic test were higher than for HPLC, but did not exceed 1.2% (CV) and 2.5% (CV), respectively. PMID:2708944

  3. Large-scale simulation of flow and transport in reconstructed HPLC-microchip packings.

    PubMed

    Khirevich, Siarhei; Höltzel, Alexandra; Ehlert, Steffen; Seidel-Morgenstern, Andreas; Tallarek, Ulrich

    2009-06-15

    Flow and transport in a particle-packed microchip separation channel were investigated with quantitative numerical analysis methods, comprising the generation of confined, polydisperse sphere packings by a modified Jodrey-Tory algorithm, 3D velocity field calculations by the lattice-Boltzmann method, and modeling of convective-diffusive mass transport with a random-walk particle-tracking approach. For the simulations, the exact conduit cross section, the particle-size distribution of the packing material, and the respective average interparticle porosity (packing density) of the HPLC-microchip packings was reconstructed. Large-scale simulation of flow and transport at Peclet numbers of up to Pe = 140 in the reconstructed microchip packings (containing more than 3 x 10(5) spheres) was facilitated by the efficient use of supercomputer power. Porosity distributions and fluid flow velocity profiles for the reconstructed microchip packings are presented and analyzed. Aberrations from regular geometrical conduit shape are shown to influence packing structure and, thus, porosity and velocity distributions. Simulated axial dispersion coefficients are discussed with respect to their dependence on flow velocity and bed porosity. It is shown by comparison to experimental separation efficiencies that the simulated data genuinely reflect the general dispersion behavior of the real-life HPLC-microchip packings. Differences between experiment and simulation are explained by differing morphologies of real and simulated packings (intraparticle porosity, packing structure in the corner regions). PMID:19459621

  4. Comparison of high performance TLC and HPLC for separation and quantification of chlorogenic acid in green coffee bean extracts.

    PubMed

    Urakova, Irina N; Pozharitskaya, Olga N; Shikov, Alexander N; Kosman, Vera M; Makarov, Valery G

    2008-02-01

    Two chromatographic methods, high-performance TLC (HPTLC) and HPLC, were developed and used for separation and quantitative determination of chlorogenic acid in green coffee bean extracts. For HPTLC silica gel Kieselgel 60 F 254 plates with ethyl acetate/dichlormethane/formic acid/acetic acid/water (100:25:10:10:11, v/v/v/v/v) as mobile phase were used. Densitometric determination of chlorogenic acid by HPTLC was performed at 330 nm. A gradient RP HPLC method was carried out at 330 nm. All necessary validation tests for both methods were developed for their comparison. There were no statistically significant differences between HPLC and HPTLC for quantitative determination of chlorogenic acid according to the test of equality of the means. PMID:18183554

  5. Survey of aflatoxins in rice from Iran using immunoaffinity column clean-up and HPLC with fluorescence detection.

    PubMed

    Feizy, J; Beheshti, H R; Fahim, N Khoshbakht; Janati, S S Fakoor; Davari, G

    2010-01-01

    A study was undertaken to determine levels of aflatoxins in rice. A total of 261 rice samples were analyzed by HPLC using a method was based on the extraction of 50 g of finely ground rice plus 5 g NaCl with 200 ml of 80% methanol. After filtration and immunoaffinity clean-up, 20 µl was injected onto the HPLC. HPLC analysis was carried out using a Genesis RP C18 column (250 × 4.6, 4 µm I.D.) and a mobile phase with a linear gradient of water/methanol/acetonitrile (6 : 2 : 2 v/v) over 16 min. Aflatoxins were determined after post-column derivatisation with iodine by fluorescence detection at excitation and emission wavelengths of 365 and 445 nm, respectively. It was found that 68.9% of the rice samples contained aflatoxin B1 at levels greater than 0.2 ng g(-1). PMID:24779626

  6. Comparison of HPLC, UV spectrophotometry and potentiometric titration methods for the determination of lumefantrine in pharmaceutical products.

    PubMed

    da Costa César, Isabela; Nogueira, Fernando Henrique Andrade; Pianetti, Gérson Antônio

    2008-09-10

    This paper describes the development and evaluation of a HPLC, UV spectrophotometry and potentiometric titration methods to quantify lumefantrine in raw materials and tablets. HPLC analyses were carried out using a Symmetry C(18) column and a mobile phase composed of methanol and 0.05% trifluoroacetic acid (80:20), with a flow rate of 1.0ml/min and UV detection at 335nm. For the spectrophotometric analyses, methanol was used as solvent and the wavelength of 335nm was selected for the detection. Non-aqueous titration of lumefantrine was carried out using perchloric acid as titrant and glacial acetic acid/acetic anhydride as solvent. The end point was potentiometrically determined. The three evaluated methods showed to be adequate to quantify lumefantrine in raw materials, while HPLC and UV methods presented the most reliable results for the analyses of tablets. PMID:18571353

  7. A new approach to the analysis of nicarbazin and ionophores in eggs by HPLC/MS/MS.

    PubMed

    Dmitrovic, Jasna; Durden, David A

    2011-01-01

    An HPLC/MS/MS method has been developed and validated for the quantification and confirmation of nicarbazin and ionophores (lasalocid, monensin, salinomycin, and narasin) in eggs. Nicarbazin is determined in the negative electrospray mode with a basic mobile phase that supports creation of negative ions. Consequently, our ability to maintain instrument sensitivity over time has significantly improved. The analysis of the ionophores is done in the positive electrospray mode using ammonium buffer for HPLC separation. Monitoring ammonium adduct parent ions resulted in enhanced sensitivity and better reproducibility of the ionophore analysis. The validation of this improved HPLC/MS/MS method for the detection of nicarbazin and the ionophores demonstrated excellent precision of below 10% RSD and lower LOD values (microg/kg) for nicarbazin (0.018), lasalocid (0.015), monensin (0.015), salinomycin (0.033), and narasin (0.039). PMID:21563675

  8. Single-run HPLC/ESI-LITMS profiling of ginsenosides in plant extracts and ginseng based products.

    PubMed

    Stavrianidi, Andrey; Rodin, Igor; Braun, Arkady; Stekolshchikova, Elena; Shpigun, Oleg

    2015-06-01

    A rapid single-run analytical approach suitable to achieve a comprehensive characterization of ginsenosides - the main bioactive compounds present in plant materials from Panax species and ginseng-based products - was developed. The method is based on high-performance liquid chromatography coupled with electrospray positive ionization linear ion trap mass spectrometry (HPLC/ESI-LITMS). The main ions in the ESI-LITMS spectra were attributed to molecular adducts with sodium and potassium and fragments corresponding to cleavage of the glycosidic bonds. The simplicity of the approach allows laborious sample preparation and sophisticated spectral information-dependent acquisition to be avoided, and provides an opportunity for rapid screening. The method may replace existing HPLC-DAD profiling approaches. The results of this study indicate that HPLC/ESI-LITMS is applicable for quality control purposes on processed products and allows the rapid and direct identification of ginsenosides in crude plant extracts. PMID:25355704

  9. Optimization of a CUPRAC-Based HPLC Postcolumn Assay and Its Applications for Ginkgo biloba L. Extracts

    PubMed Central

    Rimkiene, Laura; Ivanauskas, Liudas; Kubiliene, Asta; Vitkevicius, Konradas; Kiliuviene, Guoda; Jakstas, Valdas

    2015-01-01

    The aim of the present work was to improve and validate the HPLC-CUPRAC postcolumn method for the evaluation of active antioxidant markers from the acetonic extracts of Ginkgo biloba leaves. Improvement of the HPLC online assay was performed by evaluating the suitable loop temperature, the reaction loop length, and the impact of flow rate. Separation of the analytes was performed by the HPLC method on an ACE C18 analytical column using a gradient elution program. The separated antioxidant markers in the extracts reacted with copper(II)-neocuproine (Cu(II)-Nc) reagent in the postcolumn reaction coil. The reagent was reduced by antioxidants to the copper(I)-neocuproine (Cu(I)-Nc) chelate with a maximum absorption at 450 nm. Validation experiments confirmed sufficient precision, sensitivity, and effectiveness of the corresponding method, which could be used for further evaluations of active antioxidant compounds in similar plant materials. PMID:26236538

  10. A rapid procedure for the monitoring of amiodarone and N-desethylamiodarone by HPLC-UV detection.

    PubMed

    Juenke, JoEtta M; Brown, Paul I; McMillin, Gwendolyn A; Urry, Francis M

    2004-01-01

    This article describes a rapid isocratic high-performance liquid chromatographic (HPLC) method for the simultaneous measurement of the antiarrhythmic drug amiodarone and its potentially active metabolite N-desethylamiodarone (DEA). Following a simple liquid-liquid extraction, amiodarone and its metabolite are quantitated (0.3-6.0 mg/L) by analysis on an HPLC-UV system. The analytical time was reduced by 50%, without compromising the assay performance, when Rocket column technology was employed. The assay's limit of quantitation, linearity, imprecision, and accuracy adequately covered the therapeutic range for appropriate patient monitoring. Amiodarone and DEA can be simultaneously and accurately quantitated in serum or plasma by HPLC-UV detection with imprecision < 6% at therapeutic concentrations and a quantitation range from 0.3 to 6.0 mg/L. Monitoring of this drug can allow for effective use, while minimizing serious side effects. PMID:14987427

  11. HPLC/APCI Mass Spectrometry of Saturated and Unsaturated Hydrocarbons by Using Hydrocarbon Solvents as the APCI Reagent and HPLC Mobile Phase

    NASA Astrophysics Data System (ADS)

    Gao, Jinshan; Owen, Benjamin C.; Borton, David J.; Jin, Zhicheng; Kenttämaa, Hilkka I.

    2012-05-01

    Saturated and unsaturated, linear, branched, and cyclic hydrocarbons, as well as polyaromatic and heteroaromatic hydrocarbons, were successfully ionized by atmospheric pressure chemical ionization (APCI) using small hydrocarbons as reagents in a linear quadrupole ion trap (LQIT) mass spectrometer. Pentane was proved to be the best reagent among the hydrocarbon reagents studied. This ionization method generated different types of abundant ions (i.e., [M + H]+, M+•, [M - H]+ and [M - 2H]+ •), with little or no fragmentation. The radical cations can be differentiated from the even-electron ions by using dimethyl disulfide, thus facilitating molecular weight (MW) determination. While some steroids and lignin monomer model compounds, such as androsterone and 4-hydroxy-3-methoxybenzaldehyde, also formed abundant M+• and [M + H]+ ions, this was not true for all of them. Analysis of two known mixtures as well as a base oil sample demonstrated that each component of the known mixtures could be observed and that a correct MW distribution was obtained for the base oil. The feasibility of using this ionization method on the chromatographic time scale was demonstrated by using high-performance liquid chromatography (HPLC) with hexane as the mobile phase (and APCI reagent) to separate an artificial mixture prior to mass spectrometric analysis.

  12. Genetic, Epigenetic, and HPLC Fingerprint Differentiation between Natural and Ex Situ Populations of Rhodiola sachalinensis from Changbai Mountain, China

    PubMed Central

    Zhao, Wei; Shi, Xiaozheng; Li, Jiangnan; Guo, Wei; Liu, Chengbai; Chen, Xia

    2014-01-01

    Rhodiola sachalinensis is an endangered species with important medicinal value. We used inter-simple sequence repeat (ISSR) and methylation-sensitive amplified polymorphism (MSAP) markers to analyze genetic and epigenetic differentiation in different populations of R. sachalinensis, including three natural populations and an ex situ population. Chromatographic fingerprint was used to reveal HPLC fingerprint differentiation. According to our results, the ex situ population of R. sachalinensis has higher level genetic diversity and greater HPLC fingerprint variation than natural populations, but shows lower epigenetic diversity. Most genetic variation (54.88%) was found to be distributed within populations, and epigenetic variation was primarily distributed among populations (63.87%). UPGMA cluster analysis of ISSR and MSAP data showed identical results, with individuals from each given population grouping together. The results of UPGMA cluster analysis of HPLC fingerprint patterns was significantly different from results obtained from ISSR and MSAP data. Correlation analysis revealed close relationships among altitude, genetic structure, epigenetic structure, and HPLC fingerprint patterns (R2 = 0.98 for genetic and epigenetic distance; R2 = 0.90 for DNA methylation level and altitude; R2 = –0.95 for HPLC fingerprint and altitude). Taken together, our results indicate that ex situ population of R. sachalinensis show significantly different genetic and epigenetic population structures and HPLC fingerprint patterns. Along with other potential explanations, these findings suggest that the ex situ environmental factors caused by different altitude play an important role in keeping hereditary characteristic of R. sachalinensis. PMID:25386983

  13. HPLC-fluorescence determination of bile acids in pharmaceuticals and bile after derivatization with 2-bromoacetyl-6-methoxynaphthalene.

    PubMed

    Cavrini, V; Gatti, R; Roda, A; Cerrè, C; Roveri, P

    1993-08-01

    2-Bromoacetyl-6-methoxynaphthalene was used as a pre-chromatographic fluorescent labelling reagent for the high-performance liquid chromatographic (HPLC) analysis of bile acids. The derivatization reaction was performed in an aqueous medium in the presence of tetrahexylammonium bromide by ultrasonication at 40 degrees C to give fluorescent esters which were separated by reversed-phase HPLC and detected fluorimetrically (lambda ex = 300 nm, lambda em = 460 nm). Applications to the determination of ursodeoxycholic acid (UDCA) and chenodeoxycholic acid (CDCA) in their pharmaceutical formulations are described. The method was also applied to the determination of free and conjugated bile acids in human bile samples. PMID:8257742

  14. Clean synthesis of molecular recognition polymeric materials with chiral sensing capability using supercritical fluid technology. Application as HPLC stationary phases.

    PubMed

    da Silva, Mara Soares; Vão, Eva R; Temtem, Márcio; Mafra, Luís; Caldeira, Jorge; Aguiar-Ricardo, Ana; Casimiro, Teresa

    2010-03-15

    Molecularly imprinted polymers (MIPs) of poly(ethylene glycol dimethacrylate) and poly(N-isopropylacrylamide-co-ethylene glycol dimethacrylate) were synthesized for the first time in supercritical carbon dioxide (scCO(2)), using Boc-L-tryptophan as template. Supercritical fluid technology provides a clean and one-step synthetic route for the preparation of affinity polymeric materials with sensing capability for specific molecules. The polymeric materials were tested as stationary HPLC phases for the enantiomeric separation of L- and D-tryptophan. HPLC results prove that the synthesized MIPs are able to recognize the template molecule towards its enantiomer which opens up potential applications in chromatographic chiral separation. PMID:20096557

  15. Comparative Study of RP-HPLC and UV Spectrophotometric Techniques for the Simultaneous Determination of Amoxicillin and Cloxacillin in Capsules

    PubMed Central

    Giang, Do T; Hoang, Vu D

    2010-01-01

    Reversed-phase HPLC and UV spectrophotometric techniques using water as solvent have been developed and validated for the simultaneous determination of amoxicillin and cloxacillin in capsules. For both techniques, the linearity range of 60.073x2013;140.0 µg/mL was studied. The spectrophotometric data show that non-derivative techniques, such as absorbance ratio and compensation, and ratio spectra first-order derivative could be successfully used for the co-assay of amoxicillin and cloxacillin. Based on the statistical comparison of spectrophotometric and chromatographic data, the interchangeability between HPLC and UV spectrophotometric techniques has been suggested for the routine analysis. PMID:21264124

  16. Synthesis and characterization of a multimode stationary phase: Congo red derivatized silica in nano-flow HPLC.

    PubMed

    Zhang, Yi; Zhang, Yan; Wang, Guan; Chen, Wujuan; He, Pingang; Wang, Qingjiang

    2016-02-01

    A novel Congo red (CR) derivatized silica stationary phase was prepared and packed into a fused silica capillary tube for nano-flow HPLC. A variety of analytes including poly-aromatic hydrocarbons, parabens, acids, sulfonamides, bases, and nucleosides were successfully separated using the CR. In comparison with commercial ODS columns, this new stationary phase has a different separation mechanism (hydrophobically-assisted ion-exchange), which was evident in the separation of benzoic acid derivatives and sulfonamides. The successful application of CR-bonded silica stationary phase in the HILIC and PALC modes demonstrates the effectiveness of this potential chromatographic material in nano flow HPLC. PMID:26646316

  17. Evaluation of Pressure Stable Chip-to-Tube Fittings Enabling High-Speed Chip-HPLC with Mass Spectrometric Detection.

    PubMed

    Lotter, Carsten; Heiland, Josef J; Stein, Volkmar; Klimkait, Michael; Queisser, Marco; Belder, Detlev

    2016-08-01

    Appropriate chip-to-tube interfacing is an enabling technology for high-pressure and high-speed liquid chromatography on chip. For this purpose, various approaches, to connect pressure resistant glass chips with HPLC pumps working at pressures of up to 500 bar, were examined. Three side-port and one top-port connection approach were evaluated with regard to pressure stability and extra column band broadening. A clamp-based top-port approach enabled chip-HPLC-MS analysis of herbicides at the highest pressure and speed. PMID:27397738

  18. Application of a new HPLC-ICP-MS method for simultaneous determination of Al(3+) and aluminium fluoride complexes.

    PubMed

    Zioła-Frankowska, Anetta; Kuta, Jan; Frankowski, Marcin

    2015-10-01

    The paper presents the new HPLC-ICP-MS method used for conducting speciation analysis of aluminum as free Al(3+) and aluminum fluoride complexes during one analysis. In the study, 5% HNO3 was used as a derivative reagent in order to minimize the possibility of clogging the torch in ICP-MS. Using the new HPLC-ICP-MS method, speciation analysis of aluminum and aluminum fluoride complexes was conducted on the basis of model solutions and real samples (soil-water extracts and groundwater samples). The analysis in the presented analytical system lasts only 4 min. PMID:27441221

  19. Isolation, Cytotoxicity Evaluation and HPLC-Quantification of the Chemical Constituents from Prangos pabularia

    PubMed Central

    Farooq, Saleem; Shakeel-u-Rehman; Dangroo, Nisar Ahmad; Priya, Dev; Banday, Javid Ahmad; Sangwan, Pyare Lal; Qurishi, Mushtaq Ahmad; Koul, Surrinder; Saxena, Ajit Kumar

    2014-01-01

    Phytochemical analysis of the dichloromethane:methanol (1∶1) extract of root parts of Prangos pabularia led to the isolation of twelve cytotoxic constituents, viz., 6-hydroxycoumarin (1), 7-hydroxycoumarin (2), heraclenol-glycoside (3), xanthotoxol (4), heraclenol (5), oxypeucedanin hydrate (6), 8-((3,3-dimethyloxiran-2-yl)methyl)-7-methoxy-2H-chromen-2-one (7), oxypeucedanin hydrate monoacetate (8), xanthotoxin (9), 4-((2-hydroxy-3-methylbut-3-en-1-yl)oxy)-7H-furo[3,2-g]chromen-7-one (10), imperatorin (11) and osthol (12). The isolates were identified using spectral techniques in the light of literature. 3-(4,5-dimethyl thiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity screening of the isolated constituents was carried out against six human cancer cell lines including lung (A549 and NCI-H322), epidermoid carcinoma (A431), melanoma (A375), prostate (PC-3) and Colon (HCT-116) cell lines. Osthol (12) exhibited the highest cytotoxicity with IC50 values of 3.2, 6.2, 10.9, 14.5, 24.8, and 30.2 µM against epidermoid carcinoma (A431), melanoma (A375), lung (NCI-H322), lung (A549), prostate (PC-3) and colon (HCT-116) cell lines respectively. Epidermoid carcinoma cell line A431 was sensitive to most of the compounds followed by lung (A549) cancer cell line. Finally a simple and reliable HPLC method was developed (RP-HPLC-DAD) and validated for the simultaneous quantification of these cytotoxic constituents in Prangos pabularia. The extract was analyzed using a reversed-phase Agilent ZORBAX eclipse plus column C18 (4.6×250 mm, 5 µm) at 250 nm wavelength using a gradient water-methanol solvent system at a flow rate of 0.8 ml/min. The RP-HPLC method is validated in terms of recovery, linearity, accuracy and precision (intra and inter-day validation). This method, because of shorter analysis time, makes it valuable for the commercial quality control of Prangos pabularia extracts and its future pharmaceutical preparations. PMID:25314269

  20. Phytochemical Composition, Antioxidant Activity and HPLC Fingerprinting Profiles of Three Pyrola Species from Different Regions

    PubMed Central

    Wang, Dongmei; He, Fengyuan; Lv, Zhenjiang; Li, Dengwu

    2014-01-01

    The present study was performed to investigate the variation of phytochemical composition, antioxidant activity and High Performance Liquid Chromatography (HPLC) fingerprinting profiles of three Pyrola species. Thirteen samples (eight P. decorata, three P. calliantha and two P. renifolia) were collected from different regions in China. The tannin, hyperoside and quercetin contents of all samples were determined by reverse-phase HPLC and varied within the range 9.77–34.75, 0.34–2.16 and 0.062–0.147 mg/g dry weigh, respectively. Total flavonoid content was evaluated and varied within the range 16.22–37.82 mg/g dry weight. Antioxidant activity was determined by DPPH assay, with IC50 ranging from 7.96 to 50.33 µg/ml, ABTS•+ and FRAP assay, within the range 612.66–1021.05 and 219.64–398.12 µmol equiv. Trolox/g, respectively. These results revealed that there were significant variations in phytochemical profiles and antioxidant activity among all samples. Due to the higher phytochemical content and significant antioxidant activity, P. calliantha was selected as the most valuable species, and the P. calliantha sample from Left banner of Alxa even possessed the strongest antioxidant activity among all the thirteen samples. Futhermore, Emei Mountain was proved to be the most suitable region for producing P. decorata. Moreover, in order to further evaluate the diversities and quality of Pyrola, HPLC fingerprint analysis coupled with hierarchical cluster and discrimination analyses were introduced to establish a simple, rapid and effective method for accurate identification, classification and quality assessment of Pyrola. Thirteen samples were divided into three groups consistent with their morphological classification. Two types of discriminant functions were generated and the ratio of discrimination was 100%. This method can identify different species of Pyrola and the same species from different regions of origin. Also, it can be used to compare and

  1. 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

  2. Size Exclusion HPLC of Protein Using a Narrow-Bore Column for Evaluation of Bread-Making Quality of Hard Spring Wheat Flours

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to investigate if a narrow-bore column (NBC) (300 x 4.5 mm i.d.) improved analyses of unreduced proteins in flour by size exclusion HPLC (SE-HPLC) and subsequent evaluation of bread-making quality of hard spring wheat flours. Total protein extracts and sodium dodecyl...

  3. Quantitative determination of Zn protoporphyrin IX, heme and protoporphyrin IX in Parma ham by HPLC.

    PubMed

    Wakamatsu, Jun-Ichi; Odagiri, Hiroko; Nishimura, Takanori; Hattori, Akihito

    2009-05-01

    We measured the contents of Zn protoporphyrin IX (ZPP), heme and protoporphyrin IX (PPIX) in Parma ham by simultaneous analysis using high-performance liquid chromatography (HPLC). Extraction with ethyl acetate-acetic acid (4:1) was suitable for the quantitative analysis of ZPP. The contents of heme, ZPP and PPIX in Parma ham were 15.0-29.9, 27.7-47.0 and 0.4-1.1μg/g, respectively, and total content of porphyrin was 43.7-76.6μg/g. The amount of ZPP in Parma ham was larger than that of heme, and ZPP accounted for 60-70% of all porphyrins. PMID:20416611

  4. Development and Validation of Stability Indicating RP-HPLC Method for Voriconazole.

    PubMed

    Khetre, A B; Sinha, P K; Damle, Mrinalini C; Mehendre, R

    2009-09-01

    This study describes the development and validation of stability indicating HPLC method for voriconazole, an antifungal drug. Voriconazole was subjected to stress degradation under different conditions recommended by International Conference on Harmonization. The sample so generated was used to develop a stability-indicating high performance liquid chromatographic method for voriconazole. The peak for voriconazole was well resolved from peaks of degradation products, using a Hypersil C18 (250x4.6 mm) column and a mobile phase comprising of acetonitrile: water (40:60, v/v), at flow rate of 1 ml/min. Detection was carried out using photodiode array detector. A linear response (r > 0.99) was observed in the range of 5-25 mug/ml. The method showed good recoveries (average 100.06%) and relative standard deviation for intra and inter-day were

  5. Determination of metrafenone in vegetables by matrix solid-phase dispersion and HPLC-UV method.

    PubMed

    Li, Jianjun; Li, Yangyang; Xu, Dongliang; Zhang, Jingyu; Wang, Yuxi; Luo, Chao

    2017-01-01

    A simple method for determination of metrafenone in vegetables by matrix solid-phase dispersion (MSPD) and HPLC was developed. All vegetable samples were extracted with dichloromethane, and then the extracts were directly separated on a reversed-phase column with isocratic elution without a cleanup step. The linearity of metrafenone was good with the concentration between 0.005 and 5mg/kg, and the limit of detection (LOD) of the metrafenone was 0.002mg/kg. The recoveries ranged from 86.5% to 104.8% with the relative standard deviations (RSDs) in the range of 2.1-7.9% (n=6). The results indicated that the method was simple, rapid, highly sensitive and suitable for the determination of metrafenone in vegetables. PMID:27507450

  6. Development and Application of Multidimensional HPLC Mapping Method for O-linked Oligosaccharides

    PubMed Central

    Yagi, Hirokazu; Ohno, Erina; Kondo, Sachiko; Yoshida, Atsuhiro; Kato, Koichi

    2011-01-01

    Glycosylation improves the solubility and stability of proteins, contributes to the structural integrity of protein functional sites, and mediates biomolecular recognition events involved in cell-cell communications and viral infections. The first step toward understanding the molecular mechanisms underlying these carbohydrate functionalities is a detailed characterization of glycan structures. Recently developed glycomic approaches have enabled comprehensive analyses of N-glycosylation profiles in a quantitative manner. However, there are only a few reports describing detailed O-glycosylation profiles primarily because of the lack of a widespread standard method to identify O-glycan structures. Here, we developed an HPLC mapping method for detailed identification of O-glycans including neutral, sialylated, and sulfated oligosaccharides. Furthermore, using this method, we were able to quantitatively identify isomeric products from an in vitro reaction catalyzed by N-acetylglucosamine-6O-sulfotransferases and obtain O-glycosylation profiles of serum IgA as a model glycoprotein. PMID:24970123

  7. Acrylamide in Romanian food using HPLC-UV and a health risk assessment.

    PubMed

    Oroian, Mircea; Amariei, Sonia; Gutt, Gheorghe

    2015-01-01

    The aim of this study was to investigate the level of acrylamide from coffee, potato chips and French fries in Romanian food. According to the European Food Safety Authority, coffee beans, potato chips and French fries have the highest levels of acrylamide. For this survey, 50 samples of coffee beans, 50 samples of potato chips and 25 samples of French fries were purchased from different producers from the Romanian market. Acrylamide levels have been quantified using high-performance liquid chromatography with a diode array detector (HPLC-DAD) method, using water as mobile phase. Health risk assessment was achieved by computing the average daily intake, hazard quotient, cumulative risk, carcinogenic risk and cancer risk. For coffee, potato chips and French fries, acrylamide was not shown to pose a health risk in Romanian food. PMID:25753750

  8. Laboratory Detection and Analysis of Organic Compounds in Rocks Using HPLC and XRD Methods

    NASA Technical Reports Server (NTRS)

    Dragoi, D.; Kanik, I.; Bar-Cohen, Y.; Sherrit, S.; Tsapin, A.; Kulleck, J.

    2004-01-01

    In this work we describe an analytical method for determining the presence of organic compounds in rocks, limestone, and other composite materials. Our preliminary laboratory experiments on different rocks/limestone show that the organic component in mineralogical matrices is a minor phase on order of hundreds of ppm and can be better detected using high precision liquid chromatography (HPLC). The matrix, which is the major phase, plays an important role in embedding and protecting the organic molecules from the harsh Martian environment. Some rocks bear significant amounts of amino acids therefore, it is possible to identify these phases using powder x-ray diffraction (XRD) by crystallizing the organic. The method of detection/analysis of organics, in particular amino acids, that have been associated with life will be shown in the next section.

  9. Chemical changes during fermentation of Abhayarishta and its standardization by HPLC-DAD.

    PubMed

    Lal, Uma Ranjan; Tripathi, Shailendra Mani; Jachak, Sanjay M; Bhutani, Kamlesh Kumar; Singh, Inder Pal

    2010-04-01

    Abhayarishta is an Ayurvedic formulation prepared traditionally by the fermentation of the decoction of Terminalia chebula (pericarp), Vitis vinifera (fruits), Embelia ribes (fruits) and Madhuca indica (flowers). In the present communication, chemical changes occurring during fermentation in Abhayarishta have been studied for the purpose of its standardization. An HPLC-DAD method for quantitative estimation of selected marker constituents in the formulation has been developed and validated. A comparison of decoction and final processed formulation revealed that major polyphenolics (chebulagic and chebulinic acid) of T. chebula were hydrolyzed to their respective monomers and, consequently, there was an increase in the amount of chebulic acid, gallic acid, ellagic acid and ethyl gallate after fermentation. 5-Hydroxymethyl furfural (5-HMF) was also found in the formulation. Thus, emphasis is laid upon consideration of processing methods of formulation which has been lacking in the standardization of most of Ayurvedic formulations. PMID:20433076

  10. HPLC-Profiles of Tocopherols, Sugars, and Organic Acids in Three Medicinal Plants Consumed as Infusions.

    PubMed

    Roriz, Custódio Lobo; Barros, Lillian; Carvalho, Ana Maria; Ferreira, Isabel C F R

    2014-01-01

    Pterospartum tridentatum (L.) Willk, Gomphrena globosa L., and Cymbopogon citratus (DC.) Stapf are medicinal plants that require a more detailed chemical characterization, given the importance of their consumption as infusions. Therefore, the individual profiles in tocopherols, free sugars, and organic acids were obtained by high performance liquid chromatography (HPLC) coupled to different detectors (fluorescence, refraction index, and photodiode array, resp.). C. citratus revealed the highest content of α-, and total tocopherols, glucose, sucrose, succinic, and ascorbic acids. P. tridentatum presented the highest fructose and total sugars content. Otherwise, G. globosa showed the highest organic acids concentration. As far as we know, this is the first study reporting the mentioned chemical compounds in G. globosa and C. citratus. PMID:26904623

  11. Thiamin analysis in red wine by fluorescence reverse phase-HPLC.

    PubMed

    Liddicoat, Callum; Hucker, Barry; Liang, Hao; Vriesekoop, Frank

    2015-06-15

    The derivatization of thiamin vitamers to their respective thiochrome by ferricyanide to facilitate fluorescence detection following separation by HPLC provides a powerful analytical tool. However the polyphenolic compounds in red wine readily interact with ferricyanide, reducing the effectiveness of ferricyanide oxidation in the derivatization of thiamin. We describe a method to facilitate the removal of polyphenolic compounds that interfere with the ferricyanide derivatization of thiamin. Polyvinylpolypyrrolidone afforded the total removal of phenolic compounds from red wines and allowed a spike recovery of thiamin vitamers (101% for thiamin; 104% for TMP; and 100% for TDP) in a wide range of red wines. This research found that Merlot styles of red wine contained the highest concentration of total thiamin (29.01 ng/mL) while Pinot Noir wines contained the lowest total concentration (8.27 ng/mL). PMID:25660893

  12. Determination of synthetic food colorants in fish products by an HPLC-DAD method.

    PubMed

    Karanikolopoulos, G; Gerakis, A; Papadopoulou, K; Mastrantoni, I

    2015-06-15

    Reliable methods for quantification of synthetic water-soluble colors in complex food matrices are currently not available. The present work describes the development and validation of an improved protocol for the analysis of synthetic food colorants in complex food matrices presenting high protein and/or fat content. The method developed employs an extraction stage, followed by a subsequent sonification, centrifugation and concentration step. A final clean up via SPE on polyamide cartridges was also employed. The isolated colorants were separated and analyzed by an RP-HPLC/DAD system. High and consistent recoveries (min. 81%) and low RSDs (max. 6%) were achieved for all studied colorants. The issue of high fat content matrices was also addressed showing the need for an additional defatting step in the procedure. Overall, the protocol presented shows high precision and accuracy of detection and can provide the basis for future development of similar methods in other complex food matrices. PMID:25660877

  13. Chemical fingerprinting of Gardenia jasminoides Ellis by HPLC-DAD-ESI-MS combined with chemometrics methods.

    PubMed

    Han, Yan; Wen, Jun; Zhou, Tingting; Fan, Guorong

    2015-12-01

    A fingerprint analysis method has been developed for characterization and discrimination of Gardenia jasminoides Ellis from different areas. The chemometrics methods including similarity evaluation, principal components analysis (PCA) and hierarchical clustering analysis (HCA) were introduced to identify more useful chemical markers for improving the quality control standard of dried ripe fruits of G. jasminoides Ellis. Then the selected chemical markers were analyzed by high performance liquid chromatography-diode array detection-electrospray ionization mass spectrometry (HPLC-DAD-ESI-MS) qualitatively and quantitatively. 23 characteristic peaks were assigned while 19 peaks of them were identified by comparing retention times, UV and MS spectra with authentic compounds or literature data. Moreover, 14 of them were determined quantitatively which could effectively evaluate the quality of G. jasminoides Ellis. This study was expected to provide comprehensive information for the quality evaluation of G. jasminoides Ellis, which would be a valuable reference for further study and development of this herb and related medicinal products. PMID:26041243

  14. Identification and quantification of constituents of Gardenia jasminoides Ellis (Zhizi) by HPLC-DAD-ESI-MS.

    PubMed

    Bergonzi, M C; Righeschi, C; Isacchi, B; Bilia, A R

    2012-09-15

    A simple, rapid and specific HPLC method was carried out for the analysis of characteristic constituents in Gardenia jasminoides Ellis (Zhizi), namely iridoids, caffeoyl quinic acid derivatives and crocins. The separation was successfully obtained using a C(18) column by gradient elution with mixtures of methanol and water as mobile phases; detection wavelength was set at 240 nm for iridoid glycosides, 315 nm for quinic acid derivatives and 438 nm for crocins. The analytical method was validated and the quantification of active compounds, namely iridoids, was performed. Linearity, precision, repeatability, stability, accuracy, limit of detection (LOD) and limit of quantification (LOQ) were also reported. This assay was successfully applied for qualitative and quantitative analysis of five commercial samples of G. jasminoides Ellis. PMID:23107748

  15. [Ion pair-HPLC of some aromatic amino- and hydroxycarboxylic acids].

    PubMed

    Jira, T; Beyrich, T; Reinhardt, K

    1988-06-01

    Various factors influencing the ion-pair-HPLC separation of some aromatic amino- and hydroxycarbon acids were described and discussed. Distinct effects of the ion pair formation of organic acids with quarternary alkylammonium salts (CTAB) are recognized on condition that the carboxylic group is not blocked by intramolecular H-bonding or partial betain structure. If the carboxylic group is unconnected the retention time increases depending on the pka of the acid with increasing pH if no complete ionization exists. In order to separate similar compounds at low retention time with distinct resolution an organic modifier of suitable strength and high selectivity have to be added to the mobile phase. PMID:3212029

  16. HPLC Quantification of Phenolic Acids from Vetiveria zizanioides (L.) Nash and Its Antioxidant and Antimicrobial Activity

    PubMed Central

    Prajna, Jha; Richa, Jindal; Dipjyoti, Chakraborty

    2013-01-01

    Extraction procedure was standardized and for the soluble, glycoside, and wall-bound fractions of phenolic acids from Vetiveria zizanioides. The water soluble alkaline extract which represents the cell wall-bound fraction contained the highest amount of phenolic acids (2.62 ± 1.2 μM/g fwt GA equivalents). Increased phenolic content in the cell wall indicates more lignin deposition which has an important role in plant defense and stress mitigation. Antioxidant property expressed as percentage TEAC value obtained by ABTS assay was correlated with the amount of phenolic acids and showed a Pearson's coefficient 0.988 (significant at 0.01 level). The compounds p-coumaric acid, p-dihydroxybenzoic acid, and ferulic acid were detected in the acidic extracts by HPLC analysis. The plant extracts exhibited considerable antimicrobial activity against tested bacterial and fungal strains. PMID:26555971

  17. Anthocyanins and antioxidant capacities of six Chilean berries by HPLC-HR-ESI-ToF-MS.

    PubMed

    Ramirez, Javier E; Zambrano, Ricardo; Sepúlveda, Beatriz; Kennelly, Edward J; Simirgiotis, Mario J

    2015-06-01

    The HPLC profiles of six fruits endemic of the VIII region of Chile were investigated using high resolution mass analysis (HR-ToF-ESI-MS). The anthocyanin fingerprints generated for the fruits were compared and the antioxidant capacities measured by the scavenging of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and correlated with the inhibition of lipid peroxidation in human erythrocytes (LP) and total content of phenolics, flavonoids and anthocyanins measured by spectroscopic methods. Several anthocyanins were identified, including 3-O-glycosides derivatives of delphinidin, cyanidin, petunidin, peonidin and malvidin. Three phenolic acids (feruloyl-quinic acid, chlorogenic acid, and neochlorogenic acid) and five flavonols (hyperoside, isoquercitrin, quercetin, rutin, myricetin and isorhamnetin) were also identified. Calafate fruits showed the highest antioxidant activity. However, the highest LP activity was found for Chilean blueberries (>95%) followed by calafate fruits (91.27%) and luma (83.4%). PMID:25624212

  18. HPLC-DAD-ESI-MS/MS screening of bioactive components from Rhus coriaria L. (Sumac) fruits.

    PubMed

    Abu-Reidah, Ibrahim M; Ali-Shtayeh, Mohammed S; Jamous, Rana M; Arráez-Román, David; Segura-Carretero, Antonio

    2015-01-01

    Rhus coriaria L. (sumac) is an important crop widely used in the Mediterranean basin as a food spice, and also in folk medicine, due to its health-promoting properties. Phytochemicals present in plant foods are in part responsible for these consequent health benefits. Nevertheless, detailed information on these bioactive compounds is still scarce. Therefore, the present work was aimed at investigating the phytochemical components of sumac fruit epicarp using HPLC-DAD-ESI-MS/MS in two different ionisation modes. The proposed method provided tentative identification of 211 phenolic and other phyto-constituents, most of which have not been described so far in R. coriaria fruits. More than 180 phytochemicals (tannins, (iso)flavonoids, terpenoids, etc.) are reported herein in sumac fruits for the first time. The obtained results highlight the importance of R. coriaria as a promising source of functional ingredients, and boost its potential use in the food and nutraceutical industries. PMID:25053044

  19. HPLC determination of brain biogenic amines following treatment with bispyridinium aldoxime K203.

    PubMed

    Hashemi, F; Laufer, R; Szegi, P; Csomor, V; Kalász, H; Tekes, Kornélia

    2014-03-01

    Effect of a new acetylcholine-esterase reactivator, K203 as a new potential antidote in organophosphate intoxications was studied on dopamine (DA), homovanillic acid (HVA), serotonin (5-HT) and 5-hydroxyindolacetic acid (5-HIAA) levels in seven brain regions (cerebellum, spinal cord, hippocampus, hypothalamus, striatum, medulla oblongata and frontal cortex) of rats by an optimized and validated HPLC method. No significant change in brain level of these neurotransmitters was found either 15 or 60 min following treatment. However, when 5-HIAA/5-HT ratios were calculated as measure of turnover, significant decreases were found in the cerebellum, hippocampus, hypothalamus and the frontal cortex 15 min following K203 administration, but after 60 min only in the frontal cortex. PMID:24631794

  20. Determination of Lutein from Fruit and Vegetables Through an Alkaline Hydrolysis Extraction Method and HPLC Analysis.

    PubMed

    Fratianni, Alessandra; Mignogna, Rossella; Niro, Serena; Panfili, Gianfranco

    2015-12-01

    A simple and rapid analytical method for the determination of lutein content, successfully used for cereal matrices, was evaluated in fruit and vegetables. The method involved the determination of lutein after an alkaline hydrolysis of the sample matrix, followed by extraction with solvents and analysis by normal phase HPLC. The optimized method was simple, precise, and accurate and it was characterized by few steps that could prevent loss of lutein and its degradation. The optimized method was used to evaluate the lutein amounts in several fruit and vegetables. Rich sources of lutein were confirmed to be green vegetables such as parsley, spinach, chicory, chard, broccoli, courgette, and peas, even if in a range of variability. Taking into account the suggested reference values these vegetables can be stated as good sources of lutein. PMID:26540023

  1. A direct RP-HPLC method for the determination of furanic aldehydes and acids in honey.

    PubMed

    Spano, Nadia; Ciulu, Marco; Floris, Ignazio; Panzanelli, Angelo; Pilo, Maria I; Piu, Paola C; Salis, Severyn; Sanna, Gavino

    2009-04-15

    In this study 5-hydroxymethyl-2-furaldehyde (HMF), 2-furaldehyde, 3-furaldehyde, 2-furoic acid and 3-furoic acid are contemporarily determined in honey using a swift and direct RP-HPLC approach. The validation protocol was performed in terms of detection and quantification limits, precision (by repeatability and reproducibility), linearity and accuracy (by recovery tests); the acceptability of the precision and accuracy results was positively verified using Horwitz's model and AOAC guidelines, respectively. The method was tested on 18 honey samples of different ages, and botanical and geographical origin. HMF and 2-furaldehyde correlated highly with the age of the samples, whereas no correlation was observed with regards to 2-furaldehyde and 2-furoic acid. Hypotheses relating to the formation of minority furanic compounds are also proposed. PMID:19174244

  2. Recent advances in nonpolar and polar organic monoliths for HPLC and CEC

    PubMed Central

    Jonnada, Murthy; Rathnasekara, Renuka; Rassi, Ziad El

    2015-01-01

    This article is aimed at providing a review of the progress made in the field over the period 2011 to present in order to expand in parts on two previous reviews (S. Karenga and Z. El Rassi, Electrophoresis, 2011, 32, 90-104; D. Gunasena and Z. El Rassi, Electrophoresis, 2012, 33, 251-261). In brief, this review article describes progress made in nonpolar and polar monoliths used in reversed phase HPLC and CEC (RPC/RP-CEC) and in hydrophilic interaction liquid chromatography/CEC (HILIC/HI-CEC), respectively. This article is by no means an exhaustive review of the literature; it is rather a survey of the recent progress made in the field with 69 references published on nonpolar and polar polymeric monoliths. PMID:25266173

  3. Quantification of Caffeoylquinic Acids in Coffee Brews by HPLC-DAD

    PubMed Central

    Moeenfard, Marzieh; Rocha, Lígia; Alves, Arminda

    2014-01-01

    The influence of different brewing conditions on the concentration of the main caffeoylquinic acids (3-caffeoylquinic acid (3-CQA), 4-caffeoylquinic acid (4-CQA), and 5-caffeoylquinic acid (5-CQA)) was investigated. For this purpose, twenty-four coffee brews were extracted and analyzed using HPLC-DAD at 325 nm. Our findings demonstrate the great impact of brewing techniques on the caffeoylquinic acids (CQAs) content. The major isomer was 3-CQA, accounting for about 50% of the total CQAs, followed by 5-CQA and 4-CQA, accounting for about 24–36% for each one. The total content of CQAs was in the range of 45.79 to 1662.01 mg/L, found in iced cappuccino and pod espresso, respectively. In conclusion, this study demonstrates that coffee brews, in particular those prepared using pressurized methods, can be considered as the potential sources of antioxidants such as CQAs. PMID:25587489

  4. A method for determining arsenolipids in seawater by HPLC-high resolution mass spectrometry.

    PubMed

    Khan, Muslim; Jensen, Kenneth B; Francesconi, Kevin A

    2016-06-01

    Arsenic-containing lipids (arsenolipids), naturally occurring arsenicals in algae, have never been detected in seawater even though they might be introduced to the water column on senescence of marine algae or by active excretion. The complex nature of seawater presents an analytical challenge to detect these compounds and to monitor their environmental fate. We developed a simple sample preparation method using liquid-liquid extraction combined with HPLC-high resolution mass spectrometry (HRMS) capable of measuring six standard arsenolipids in seawater at the ng As/L level (<1% of the total arsenic in seawater). The method is suitable for studies on the biotransformation and pathways of arsenolipids in the marine environment. When we applied the method to four samples of natural seawater, however, we did not find any of the six standard arsenolipids. PMID:27130122

  5. Comparative HPLC-MSn analysis of canine and human meibomian lipidomes: many similarities, a few differences

    NASA Astrophysics Data System (ADS)

    Butovich, Igor A.; Borowiak, Anna M.; Eule, J. Corinna

    2011-06-01

    The aim of this study was to evaluate the lipidome of meibomian gland secretions in canines (cMGS) - a common pet and laboratory animal - and to compare it with that of human MGS (hMGS), to determine whether canines could be used as a valid experimental animal model in studies of the biochemistry and physiology of the human ocular surface in general, and of the Meibomian glands in particular. The MGS of both species were evaluated using HPLC in combination with atmospheric pressure chemical ionization ion trap mass spectrometry. The main lipid classes found in cMGS were very long chain cholesteryl esters, wax esters, (O-acyl)-omega-hydroxy fatty acids (OAHFA), and cholesteryl esters of OAHFA. The lipidomes of cMGS and hMGS were found to be qualitatively similar, which implies similar biosynthetic and biodegradation pathways in canines and humans. However, some quantitative differences between the two were observed.

  6. Clinical applications of HPLC-ICP-MS element speciation: A review.

    PubMed

    Delafiori, Jeany; Ring, Gavin; Furey, Ambrose

    2016-06-01

    Arsenic (As), Selenium (Se) and Mercury (Hg) are three trace elements that have been the subject of much analytical discussion and investigation over the last three decades. While Selenium (Se) is among the list of essential trace elements necessary for the regulation of metabolic processes and overall health, As and Hg are not, and have been the centre of various cases surrounding the contamination of food, water and the environment. The focus of this review is to explore the area of chemical speciation, particularly as it relates to the measurement of these elements in various clinical matrices by HPLC-ICP-MS. This review will highlight the importance of accurately identifying the various chemical species of each of these elements, especially when considering their respective toxicological impacts on human health. PMID:27130123

  7. HPLC profiling of antimicrobial and antioxidant phyco sugars isolated from the South West coast of India.

    PubMed

    Kailas, Abhilash Parameswaran; Nair, Sukumaran Muraleedharan

    2016-10-20

    Phyco sugars isolated from the South West coast of India are commercially and therapeutically interesting due to their various biological activities. These sugars were isolated from six (three red and three green) seaweed species using water at 100°C followed by precipitation using ethanol. The physical, chemical and biological characteristics were explored with specific highlights onto the specific rotation, HPLC-RI sugar speciation, antioxidant and antimicrobial activities. The biological properties were evaluated based on multiple methods and standards, such that the actual nature of the sugar is understood. G. corticata var. cylindrica (31.66%) had the highest sugar content. All the sugars had levo rotatory specific rotation and interesting chemical characteristics. Sugars isolated had competitive biological activities and had the presence of seven monosaccharides and one disaccharide. The results highlighted the socio-economic importance of seaweeds which could be developed as a potential source of bioactive compounds in the upcoming future. PMID:27474603

  8. Determination of some polyphenolic compounds from Allium species by HPLC-UV-MS.

    PubMed

    Parvu, Marcel; Toiu, Anca; Vlase, Laurian; Alina Parvu, Elena

    2010-09-01

    Five Allium species (Allium obliquum L., A. senescens L. subsp. montanum (Fries) Holub, A. schoenoprasum L. subsp. schoenoprasum, A. fistulosum L. and A. ursinum L.) were analysed in order to determine the presence of 19 polyphenolic compounds through an HPLC method coupled with UV and mass spectrometry detection. The pattern of phenol carboxylic acids indicates the presence of p-coumaric and ferulic acids in all species. Isoquercitrin was found in A. obliquum, A. schoenoprasum and A. fistulosum, rutin in A. senescens subsp. montanum and A. schoenoprasum, whereas quercitrin was found only in A. fistulosum, so they represent potential taxonomic markers that differentiate the four plants. Luteolin and apigenin were identified before and after hydrolysis only in A. obliquum. The amounts of all polyphenols were higher in hydrolysed samples, suggesting that these substances are present both as unbonded and bonded glycosides and/or esters. Our study showed large differences between the five Allium species, both qualitative and quantitative. PMID:20419559

  9. Reverse-phase HPLC of benzylpropionitrile dithiocarbamate complexes for the determination of priority pollutant metals

    SciTech Connect

    Park, Y.J.

    1990-01-01

    A new dithiocarbamate, benzylpropionitrile dithiocarbamate (BPDTC), has been synthesized for use in metal analysis. The HPLC behavior of metal chelates of BPDTC has been investigated for the simultaneous determination of antimony, cadmium, chromium, copper, mercury, nickel, lead, selenium, thallium, and zinc, all of which are on the Environmental Protection Agency's list of priority pollutant metals. Metals are extracted into dichloromethane as BPDTC chelates, and then separated on a C-18 column. Cobalt is added as an internal standard. The effects of pH and of three organic modifiers (methanol, acetonitrile, tetrahydrofuran) of the mobile phase on retention time have been investigated. Addition of dichloromethane to the mobile phase increases solubility and chelate stability, and improves the separation of metal BPDTC complexes. BPDTC is added to the aqueous mobile phase to reduce on-column dissociation of the complexes. Detection limits at 260 nm are in the range of 0.1 to 3 ppb using a 1 liter sample.

  10. Microfluidic Precolumn Derivatization of Environmental Phenols with Coumarin-6-Sulfonyl Chloride and HPLC Separation.

    PubMed

    Suliman, FakhrEldin O; Al-Busaidi, Jihad N; Al-Lawati, Hiader A J; Al-Kindy, Salma M Z

    2015-09-01

    A simple, fast, sensitive and versatile method for the analysis of phenols in water is proposed using microfluidic precolumn derivatization with the fluorogenic label coumarin-6-sulfonyl chloride (C6SCl) and HPLC separation on monolithic columns. Phenols react with C6SCl within 3.0 min in the microreactor at ambient temperature to produce phenol-coumarin sulphonamides derivatives which were separated in reversed phase high-performance liquid chromatography followed by postcolumn ring-opening and fluorescence detection at λexc = 360 nm and λem = 460 nm. The optimum conditions for the derivatization, separation and ring-opening reaction have been established. The calibration curves were linear for the studied phenols in the range of 0.75-12.5 mg L(-1). The application of the method to environmental samples was demonstrated by analyzing tap and fountain water samples spiked with the phenolic compounds. PMID:25809998

  11. Profiling the phenolic compounds of Artemisia pectinata by HPLC-PAD-MSn.

    PubMed

    Ma, Chao-Mei; Hattori, Masao; Chen, Hu-Biao; Cai, Shao-Qing; Daneshtalab, Mohsen

    2008-01-01

    An HPLC-PAD-MS(n) method was employed to profile the phenolic compounds of the aerial part of Artemisia pectinata (Neopallasia pectinata), a plant with no previous reports concerning its phenolic constituents. Three isomers of trans-caffeoylquinic acid accompanied by cis-5-caffeoylquinic acid, six isomers of trans-dicaffeoylquinic acid, two isomers of methyl trans-dicaffeoylquinate (including one new isomer), a trans-caffeoylferuloylquinic acid and three flavanoids were identified unambiguously by analysis of their UV and MS(n) spectra in comparison with standard compounds that were isolated from natural sources, or synthesised, or were surrogate standards (green coffee extract). Other compounds were identified by analysis of their UV and MSn data in comparison with those reported in the literature. MS(n) experiments also suggested the presence of groups of dicaffeoylquinic acid glycosides, caffeoylquinic acid diglycosides, caffeoylquinic acid glycosides and quinic acid diglycosides. PMID:17994537

  12. Pentaerythritol Tetranitrate (PETN) Surveillance by HPLC-MS: Instrumental Parameters Development

    SciTech Connect

    Harvey, C A; Meissner, R

    2005-11-04

    Surveillance of PETN Homologs in the stockpile here at LLNL is currently carried out by high performance liquid chromatography (HPLC) with ultra violet (UV) detection. Identification of unknown chromatographic peaks with this detection scheme is severely limited. The design agency is aware of the limitations of this methodology and ordered this study to develop instrumental parameters for the use of a currently owned mass spectrometer (MS) as the detection system. The resulting procedure would be a ''drop-in'' replacement for the current surveillance method (ERD04-524). The addition of quadrupole mass spectrometry provides qualitative identification of PETN and its homologs (Petrin, DiPEHN, TriPEON, and TetraPEDN) using a LLNL generated database, while providing mass clues to the identity of unknown chromatographic peaks.

  13. High-capacity stationary phases containing heavy atoms for HPLC separation of fullerenes

    SciTech Connect

    Kimata, Kazuhiro |; Hirose, Tsunehisa; Moriuchi, Kouji; Hosoya, Ken; Araki, Takeo; Tanaka, Nobuo

    1995-08-01

    A high-capacity stationary phase for the separation of fullerenes was prepared by immobilizing 3-[(pentabromobenzyl)oxy]propylsilyl (PBB) groups onto silica surfaces. The stationary phase was developed by a reciprocal approach. This was possible by finding the structure of solvents that provided high solubilities as well as high eluent strength for chromatographic elution of fullerenes. The increased solubility and increased eluent strength for C{sub 60} seen with solvents containing heavy heteroatoms suggested the preferential interaction of C{sub 60} with such solvent molecules. The stationary phases containing sulfur, chlorine, or bromine in fact resulted in longer retention of fullerenes. The PBB silica showed high retentivity with excellent efficiency for fullerenes, permitting the use of solvents providing high solubilities, such as carbon disulfide and 1,2,4-trichlorobenzene for gramscale separations with ordinary HPLC equipment. 22 refs., 6 figs., 3 tabs.

  14. Molecular diversity of cereulide detected by means of nano-HPLC-ESI-Q-TOF-MS

    NASA Astrophysics Data System (ADS)

    Pitchayawasin, Suthasinee; Isobe, Minoru; Kuse, Masaki; Franz, Thomas; Agata, Norio; Ohta, Michio

    2004-07-01

    Cereulide is a cyclic dodecadepsipeptide from a pathogenic bacteria Bacillus cereus, which shows the emetic toxicity. Molecular diversity, or variety in homologation was found as a minor constituent of this cyclic peptide. Its molecular weight is 1152 but its homologs were observed as 1138 and 1166, which had 14 mass lower and higher differences from cereulide. This homologation was observed in about 10% of cereulide. It seemed to be difficult to determine the heterogeneous amino acids directly by MS/MS analysis on the intact molecules of cereulide. And hydrolysis of this cyclic peptide gave dipeptides, which were analyzed to determine their heterogeneous components by means of nano-HPLC-ESI-Q-TOF-MS and MS/MS. Among all amino- and oxy-acids, we found that O-Val and O-Leu were the keys of variation in cereulide. These findings will be significant to establish an identification method for pathogenic bacteria on the basis of biosynthetic pathways.

  15. The determination of biurea in the presence of azodicarbonamide by HPLC.

    PubMed

    Bechtold, W E; Shopp, G M; Cheng, Y S

    1988-01-01

    Azodicarbonamide (ADA), a solid blowing agent used in the manufacture of plastics, has been selected for inhalation toxicity testing by the National Toxicology Program. To test for decomposition of ADA during aerosolization, an HPLC method was developed to quantitate the relative amounts of one possible degradation product, biurea, in bulk samples and filter samples collected after aerosolization. The method uses a C18 column with 10-micron particles, UV monitoring at 190 nm for biurea and 425 nm for ADA, and a mobile phase of 100% water. Quantitation is with 14C-labeled biurea and ADA as external standards. The assay was validated by spiking bulk ADA with projected levels of 1, 2, and 3% biurea. Levels of biurea bound in both bulk and filter-collected aerosol samples of ADA were both 0.50%, with relative standard deviations of 13 and 26%, respectively. PMID:3379928

  16. HPLC-Profiles of Tocopherols, Sugars, and Organic Acids in Three Medicinal Plants Consumed as Infusions

    PubMed Central

    Roriz, Custódio Lobo; Barros, Lillian; Carvalho, Ana Maria; Ferreira, Isabel C. F. R.

    2014-01-01

    Pterospartum tridentatum (L.) Willk, Gomphrena globosa L., and Cymbopogon citratus (DC.) Stapf are medicinal plants that require a more detailed chemical characterization, given the importance of their consumption as infusions. Therefore, the individual profiles in tocopherols, free sugars, and organic acids were obtained by high performance liquid chromatography (HPLC) coupled to different detectors (fluorescence, refraction index, and photodiode array, resp.). C. citratus revealed the highest content of α-, and total tocopherols, glucose, sucrose, succinic, and ascorbic acids. P. tridentatum presented the highest fructose and total sugars content. Otherwise, G. globosa showed the highest organic acids concentration. As far as we know, this is the first study reporting the mentioned chemical compounds in G. globosa and C. citratus. PMID:26904623

  17. Screening and HPLC-Based Activity Profiling for New Antiprotozoal Leads from European Plants

    PubMed Central

    Zimmermann, Stefanie; Thomi, Semira; Kaiser, Marcel; Hamburger, Matthias; Adams, Michael

    2012-01-01

    Based on a survey of remedies used in Renaissance Europe to treat malaria, we prepared and screened a library of 254 extracts from 61 plants for antiplasmodial activity in vitro. HPLC-based activity profiling was performed for targeted identification of active constituents in extracts. One of the most remarkable results was the identification of onopordopicrin, a germacranolide sesquiterpene lactone isolated from Arctium nemorosum as a potent inhibitor of P. falciparum with an IC50 of 6.9 μM. It was tested similarly against Trypanosoma brucei rhodesiense, the parasite which causes African sleeping sickness. With an IC50 of 0.37 μM, onopordopicrin was one of the most potent natural products reported so far. Cytotoxicity was determined against rat myoblast L6 cells (IC50: 3.06). PMID:22396915

  18. Two validated HPLC methods for the quantification of alizarin and other anthraquinones in Rubia tinctorum cultivars.

    PubMed

    Derksen, Goverdina C H; Lelyveld, Gerrit P; van Beek, Teris A; Capelle, Anthony; de Groot, A E

    2004-01-01

    Direct and indirect HPLC-UV methods for the quantitative determination of anthraquinones in dried madder root have been developed, validated and compared. In the direct method, madder root was extracted twice with refluxing ethanol-water. This method allowed the determination of the two major native anthraquinone glycosides lucidin primeveroside and ruberythric acid. In the indirect extraction method, the anthraquinone glycosides were first converted into aglycones by endogenous enzymes and the aglycones were subsequently extracted with tetrahydrofuran-water and then analysed. In this case the anthraquinones alizarin, purpurin and nordamnacanthal may be determined. The content of nordamnacanthal is proportional to the amount of lucidin primeveroside originally present. The indirect extraction method is easier to apply. Different madder cultivars were screened for their anthraquinone content. PMID:15599964

  19. A Stability Indicating HPLC Method for the Determination of Nitisinone in Capsules.

    PubMed

    Souri, Effat; Lahiji, Farnaz R; Nourhashemi, Tannaz; Jalalizadeh, H

    2015-01-01

    In this study a simple and efficient stability-indicating HPLC method with short run time was developed for the determination of nitisinone. The stress degradation of nitisinone was studied in different acidic, basic, oxidative, thermal and photolytic conditions. The chromatographic separation was achieved on a Nova-Pak C18 column using a mixture of 50 mM NaH2PO4 (pH 2.5) and acetonitrile (45:55, v/v) as mobile phase. UV detection was performed at 280 nm. Good linearity was observed over the concentration range of 0.5-50 μg/ml with r(2)>0.999. The within-day and between-day precision values were less than 2%. The proposed method could be used for the determination of nitisinone in the presence of its degradation products and also dosage form excipients for the quality control purposes. PMID:26180282

  20. HPLC determination of isoflavone levels in osage orange from the Midwest and southern United States.

    PubMed

    Darji, Ketur; Miglis, Cristina; Wardlow, Ashley; Abourashed, Ehab A

    2013-07-17

    The fruit of the Maclura pomifera tree is a sustainable source for the pharmacologically interesting isoflavones, osajin and pomiferin. A reversed-phase HPLC method was developed to identify osage orange samples with high isoflavone content and to determine the optimum conditions for sample preparation. Analytical run time was 8 min at a flow rate of 1 mL/min using a gradient of acetonitrile in H2O (0.1% formic acid) and UV peak detection at 274 nm. The method was validated for specificity, accuracy, precision, and limits of detection and quantitation (LOD/LOQ). The method was applied to determine the levels of osajin and pomiferin in extracts prepared from different samples of osage orange growing in the Midwest and southern United States. Results demonstrated the effect of different variables, such as sample preparation, geographical location, and growth stage, on the levels of osajin and pomiferin in analyzed samples. PMID:23772950

  1. HPLC Determination of Isoflavone Levels in Osage Orange from the United States Midwest and South

    PubMed Central

    Darji, Ketur; Miglis, Cristina; Wardlow, Ashley; Abourashed, Ehab A.

    2013-01-01

    The fruit of Maclura pomifera tree is a sustainable source for the pharmacologically interesting isoflavones, osajin and pomiferin. A reversed-phase HPLC method was developed to identify osage orange samples with high isoflavone content and to determine the optimum conditions for sample preparation. Analytical run time was 8 min at a flow rate of 1 mL/min using a gradient of acetonitrile in H2O (0.1% formic acid) and UV peak detection at 274 nm. The method was validated for specificity, accuracy, precision, and limits of detection and quantitation (LOD/LOQ). The method was applied to determine the levels of osajin and pomiferin in extracts prepared from different samples of osage orange growing in the United States Midwest and South. Results demonstrated the effect of different variables, such as sample preparation, geographical location, and growth stage, on the levels of osajin and pomiferin in analyzed samples. PMID:23772950

  2. Determination of some anticonvulsants, antiarrhythmics, benzodiazepines, xanthines, paracetamol and chloramphenicol by reversed phase HPLC.

    PubMed

    Willems, H J; Van der Horst, A; De Goede, P N; Haakmeester, G J

    1985-08-23

    In this article assays are described for caffeine, theophylline, procainamide, N-acetylprocainamide, quinidine, dihydroquinidine, paracetamol, phenobarbital, phenytoin, carbamazepine, chloramphenicol, oxazepam, temazepam, diazepam, desmethyldiazepam, chlordiazepoxide, desmethylchlordiazepoxide and demoxepam using a uniform working procedure, five (slightly) different mobile phases and one HPLC system. Changing from one eluent to another is simple and a stable base-line is achieved within half an hour. Three of the five eluents are interchangeable and recycling of eluent causes no problems. Sample pretreatment is a single step extraction. Interferences can be overcome by changing the selectivity of the eluent by adjusting the tetrahydrofuran or triethylamine content. Furthermore it is shown how triethylamine can improve peak shapes of basic components and shorten their retention times. PMID:2864679

  3. Structural Analysis and Quantitative Determination of Clevidipine Butyrate Impurities Using an Advanced RP-HPLC Method.

    PubMed

    Zhou, Yuxia; Zhou, Fan; Yan, Fei; Yang, Feng; Yao, Yuxian; Zou, Qiaogen

    2016-03-01

    Eleven potential impurities, including process-related compounds and degradation products, have been analyzed by comprehensive studies on the manufacturing process of clevidipine butyrate. Possible formation mechanisms could also be devised. MS and NMR techniques have been used for the structural characterization of three previously unreported impurities (Imp-3, Imp-5 and Imp-11). To separate and quantify the potential impurities in a simultaneous fashion, an efficient and advanced RP-HPLC method has been developed. In doing so, four major degradation products (Imp-2, Imp-4, Imp-8 and Imp-10) can be observed under varying stress conditions. This analytical method has been validated according to ICH guidelines with respect to specificity, accuracy, linearity, robustness and stability. The method described has been demonstrated to be applicable in routine quality control processes and stability evaluation studies of clevidipine butyrate. PMID:26489435

  4. A Stability Indicating HPLC Method for the Determination of Nitisinone in Capsules

    PubMed Central

    Souri, Effat; Lahiji, Farnaz R.; Nourhashemi, Tannaz; Jalalizadeh, H.

    2015-01-01

    In this study a simple and efficient stability-indicating HPLC method with short run time was developed for the determination of nitisinone. The stress degradation of nitisinone was studied in different acidic, basic, oxidative, thermal and photolytic conditions. The chromatographic separation was achieved on a Nova-Pak C18 column using a mixture of 50 mM NaH2PO4 (pH 2.5) and acetonitrile (45:55, v/v) as mobile phase. UV detection was performed at 280 nm. Good linearity was observed over the concentration range of 0.5-50 μg/ml with r2>0.999. The within-day and between-day precision values were less than 2%. The proposed method could be used for the determination of nitisinone in the presence of its degradation products and also dosage form excipients for the quality control purposes. PMID:26180282

  5. Simple, Precise and Accurate HPLC Method of Analysis for Nevirapine Suspension from Human Plasma

    PubMed Central

    Halde, S.; Mungantiwar, A.; Chintamaneni, M.

    2011-01-01

    A selective and sensitive high performance liquid chromatography with UV detector (HPLC-UV) method was developed and validated from human plasma. Nevirapine and internal standard (IS) zidovudine were extracted from human plasma by liquid-liquid extraction process using methyl tert-butyl ether. The samples were analysed using Inertsil ODS 3, 250×4.6 mm, 5 μ column using a mobile phase consists of 50 mM sodium acetate buffer solution (pH-4.00±0.05): acetonitrile (73:27 v/v). The method was validated over a concentration range of 50.00 ng/ml to 3998.96 ng/ml. The method was successfully applied to bioequivalence study of 10 ml single dose nevirapine oral suspension 50 mg/5 ml in healthy male volunteers. PMID:22707826

  6. Resonance light scattering determination of 6-mercaptopurine coupled with HPLC technique.

    PubMed

    Li, Ai Ping; Peng, Jing Dong; Zhou, MingQiong; Zhang, Jin

    2016-02-01

    A simple, fast, costless, sensitive and selective method of resonance light scattering coupled with HPLC was established for the determination of 6-mercaptopurine in human urine sample. In a Britton-Robinson buffer solution of pH5.5, the formation of coordination complex between 6-mercaptopurine and metal palladium (II) led to enhance the RLS intensity of the system. The RLS signal was detected by fluorescence detector at λ(ex)=λ(em)=315 nm. The analytical parameters were provided by the coupled system, the linear of 6-mercaptopurine response from 0.0615 to 2.40 μg L(-1) and the limit of detection (S/N=3) was 0.05 μg L(-1). The presented method has been applied to determine 6-mercaptopurine in human urine samples which obtained satisfactory results. Moreover, the reaction mechanism and possible reasons for enhancement of RLS were fully discussed. PMID:26479445

  7. Extraction and identification of flavonoids from parsley extracts by HPLC analysis

    NASA Astrophysics Data System (ADS)

    Stan, M.; Soran, M. L.; Varodi, C.; Lung, I.

    2012-02-01

    Flavonoids are phenolic compounds isolated from a wide variety of plants, and are valuable for their multiple properties, including antioxidant and antimicrobial activities. In the present work, parsley (Petroselinum crispum L.) extracts were obtained by three different extraction techniques: maceration, ultrasonic-assisted and microwave-assisted solvent extractions. The extractions were performed with ethanol-water mixtures in various ratios. From these extracts, flavonoids like the flavones apigenin and luteolin, and the flavonols quercetin and kaempferol were identified using an HPLC Shimadzu apparatus equipped with PDA and MS detectors. The separation method involved a gradient step. The mobile phase consisted of two solvents: acetonitrile and distilled water with 0.1% formic acid. The separation was performed on a RP-C18 column.

  8. Resonance light scattering determination of 6-mercaptopurine coupled with HPLC technique

    NASA Astrophysics Data System (ADS)

    Li, Ai Ping; Peng, Jing Dong; Zhou, MingQiong; Zhang, Jin

    2016-02-01

    A simple, fast, costless, sensitive and selective method of resonance light scattering coupled with HPLC was established for the determination of 6-mercaptopurine in human urine sample. In a Britton-Robinson buffer solution of pH 5.5, the formation of coordination complex between 6-mercaptopurine and metal palladium (II) led to enhance the RLS intensity of the system. The RLS signal was detected by fluorescence detector at λex = λem = 315 nm. The analytical parameters were provided by the coupled system, the linear of 6-mercaptopurine response from 0.0615 to 2.40 μg L- 1 and the limit of detection (S/N = 3) was 0.05 μg L- 1. The presented method has been applied to determine 6-mercaptopurine in human urine samples which obtained satisfactory results. Moreover, the reaction mechanism and possible reasons for enhancement of RLS were fully discussed.

  9. Quantification of Caffeoylquinic Acids in Coffee Brews by HPLC-DAD.

    PubMed

    Moeenfard, Marzieh; Rocha, Lígia; Alves, Arminda

    2014-01-01

    The influence of different brewing conditions on the concentration of the main caffeoylquinic acids (3-caffeoylquinic acid (3-CQA), 4-caffeoylquinic acid (4-CQA), and 5-caffeoylquinic acid (5-CQA)) was investigated. For this purpose, twenty-four coffee brews were extracted and analyzed using HPLC-DAD at 325 nm. Our findings demonstrate the great impact of brewing techniques on the caffeoylquinic acids (CQAs) content. The major isomer was 3-CQA, accounting for about 50% of the total CQAs, followed by 5-CQA and 4-CQA, accounting for about 24-36% for each one. The total content of CQAs was in the range of 45.79 to 1662.01 mg/L, found in iced cappuccino and pod espresso, respectively. In conclusion, this study demonstrates that coffee brews, in particular those prepared using pressurized methods, can be considered as the potential sources of antioxidants such as CQAs. PMID:25587489

  10. HPLC method for identification and quantification of benzimidazole derivatives in antiparasitic drugs.

    PubMed

    Kulik, Anna; Białecka, Wanda; Podolska, Marzena; Kwiatkowska-Puchniarz, Barbara; Mazurek, Aleksander

    2011-01-01

    The subject of the study was to develop a versatile HPLC system for identification and determination of four benzimidazole derivatives in the antiparasitic drugs. The tests covered: Zentel, Panacur, Vermox tablets and Systamex suspension. A satisfactory separation was obtained using the Nucleosil C8 column in the gradient system composed of mobile phase A: 85% orthophosphoric acid / water / acetonitrile in 0.05:75:25, v/v/v ratio, and mobile phase B: 85% orthophosphoric acid / water / acetonitrile in 0.05:50:50, v/v/v ratio. Both phases were adjusted to pH = 4.5 with 15% sodium hydroxide solution. A detection at 288 nm for oxfendazole and 254 nm for albendazole, fenbendazole and mebendazole was applied. The correlation coefficients in the range 0,9997 - 0,9999 proved that the calibration curves were linear. The method was validated in terms of selectivity, accuracy and precision. PMID:22125945

  11. HPLC-DPPH Screening Method for Evaluation of Antioxidant Compounds in Corylus Species.

    PubMed

    Riethmüller, Eszter; Könczöl, Arpad; Szakál, Dorottya; Végh, Krisztina; Balogh, György T; Kéry, Ágnes

    2016-05-01

    Corylus avellana L., C. colurna L. and C. maxima Mill. have been used in traditional medicine for a long time for the treatment of various diseases, such as phlebitis, varicose veins, haemorrhoidal symptoms and eczema. Our previous studies indicated the presence of flavonol-3-O-glycosides, diarylheptanoids and caffeic acid derivatives in the bark and leaf extracts of the three species mentioned above. Comparison of in vitro DPPH scavenging activity of the Corylus extracts prepared with ethyl acetate and methanol to those of well-known antioxidant phenolics was performed. The contribution of certain compounds to the total antioxidant activity of the extracts was investigated by developing a HPLC method coupled to the DPPH radical scavenging assay. PMID:27319139

  12. HPLC-UV analysis of thymidine and deoxyuridine in plasma of patients with thymidine phosphorylase deficiency.

    PubMed

    Mohamed, Susan; Caporali, Leonardo; De Giorgio, Roberto; Carelli, Valerio; Contin, Manuela

    2014-02-15

    We present a simple, fast and validated method for the determination of the two nucleosides thymidine (dThd) and deoxyuridine (dUrd) in plasma of patients with symptoms suggestive of mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), using high performance liquid chromatography coupled with ultraviolet spectrophotometric detection (HPLC-UV). Plasma sample (100μL) pretreatment was based on simple deproteinization by 1.2M perchloric acid, using theophylline as internal standard (I.S.). HPLC-UV analysis was carried out on a Synergi 4μm Hydro-RP, 150×4mm I.D. column, at room temperature. The mobile phase was a mixture of potassium dihydrogen phosphate buffer (20mM, pH 4.5) and acetonitrile (95:5, v/v), at an isocratic flow rate of 0.7mL/min. The UV detector was set at 267nm. The chromatographic run lasted 19min. Similar pyrimidine nucleotides and nucleosides do not interfere with the assay. Calibration curves were linear for both dThd and dUrd over a range of 0.5 to 5.0μg/mL. The limit of quantitation was 0.5μg/mL for both nucleosides and the absolute recovery was >90% for dThd, dUrd and the I.S. Both intra- and inter-assay precision and accuracy were lower than 10% at all tested concentrations. The proposed method was successfully applied to measure plasma concentrations of dThd and dUrd in two MNGIE patients. This assay simplifies both plasma pretreatment and chromatographic conditions of previously reported procedures and describes the first validated method for the determination of the two nucleotides in human plasma. PMID:24463401

  13. Stability-indicating HPLC Method for Simultaneous Determination of Terbutaline Sulphate, Bromhexine Hydrochloride and Guaifenesin

    PubMed Central

    Porel, A.; Haty, Sanjukta; Kundu, A.

    2011-01-01

    The aim of the present study was the development and subsequent validation of a simple, precise and stability-indicating reversed phase HPLC method for the simultaneous determination of guaifenesin, terbutaline sulphate and bromhexine hydrochloride in the presence of their potential impurities in a single run. The photolytic as well as hydrolytic impurities were detected as 3,5-dihydroxybenzoic acid, 3,5-dihydroxybenzaldehyde, 1-(3,5-dihydroxyphenyl)-2-[(1,1-dimethylethyl) amino]-ethanone from terbutaline, 2-methoxyphenol and an unknown impurity identified as (2RS)-3-(2-hydroxyphenoxy)-propane-1,2-diol from guaifenesin. The chromatographic separation of all the three active components and their impurities was achieved on Wakosil II column, using phosphate buffer (pH 3.0) and acetonitrile as mobile phase which was delivered initially in the ratio of 80:20 (v/v) for 18 min, then changed to 60:40 (v/v) for next 12 min, and finally equilibrated back to 80:20 (v/v) for 10 min. Other HPLC parameters were: Flow rate at 1.0 ml/min, detection wavelengths 248 and 280 nm, injection volume 10 μl. The calibration graphs plotted with five concentrations of each component were linear with a regression coefficient R2 >0.9999. The limit of detection and limit of quantitation were estimated for all the five impurities. The established method was then validated for linearity, precision, accuracy, and specificity and demonstrated to be applicable to the determination of the active ingredients in commercial and model cough syrup. No interference from the formulation excipients was observed. These results suggest that this LC method can be used for the determination of multiple active ingredients and their impurities in a cough and cold syrup. PMID:22131621

  14. New benzimidazole derivatives with potential cytotoxic activity--study of their stability by RP-HPLC.

    PubMed

    Błaszczak-Świątkiewicz, Katarzyna; Mirowski, Marek; Kaplińska, Katarzyna; Kruszyński, Rafał; Trzęsowska-Kruszyńska, Agata; Mikiciuk-Olasik, Elżbieta

    2012-01-01

    Obtained benzimidazole derivatives, our next synthesized heterocyclic compounds, belong to a new group of chemical bondings with potential anticancer properties (Błaszczak-Świątkiewicz & Mikiciuk-Olasik, 2006, J Liguid Chrom Rel Tech 29: 2367-2385; Błaszczak-Świątkiewicz & Mikiciuk-Olasik, 2008, Wiad Chem 62: 11-12, in Polish; Błaszczak-Świątkiewicz & Mikiciuk-Olasik, 2011, J Liguid Chrom Rel Tech 34: 1901-1912). We used HPLC analysis to determine stability of these compounds in 0.2% DMSO (dimethyl sulfoxide). Optimisation of the chromatographic system and validation of the established analytical method were performed. Reversed phases (RP-18) and a 1:1 mixture of acetate buffer (pH 4.5) and acetonitrile as a mobile phase were used for all the analysed compounds at a flow rate 1.0 mL/min. The eluted compounds were monitored using a UV detector, the wavelength was specific for compounds 6 and 9 and compounds 7 and 10. The retention time was specific for all four compounds. The used method was found to have linearity in the concentration range of (0.1 mg/mL-0.1 μg/mL) with a correlation coefficient not less than r(2)=0.9995. Statistical validation of the method proved it to be a simple, highly precise and accurate way to determine the stability of benzimidazole derivatives in 0.2% DMSO. The recoveries of all four compounds examined were in the range 99.24-100.00%. The developed HPLC analysis revealed that the compounds studied remain homogeneous in 0.2% DMSO for up to 96 h and that the analysed N-oxide benzimidazole derivatives do not disintegrate into their analogues - benzimidazole derivatives. Compounds 8, 6 and 9 exhibit the best cytotoxic properties under normoxic conditions when tested against cells of human malignant melanoma WM 115. PMID:22693687

  15. A Stability-Indicating RP-HPLC Assay Method for 5-Fluorouracil

    PubMed Central

    Sinha, V. R.; Kumar, R. V.; Bhinge, J. R.

    2009-01-01

    The present study describes the development of a validated RP-HPLC method for the determination of 5-fluorouracil in presence of its degradation products or other pharmaceutical excipients. Stress studies were performed on 5-fluorouracil and it was found that it degrades sufficiently in alkaline conditions, while negligible degradation was observed in acidic, neutral, oxidative and photolytic conditions. The peaks of the degradation products were not observed in the chromatogram due to the nonchromophoric nature of the degradation moiety formed. The separations were carried out on a C-18 reversed phase column (Phenomenex; Prodigy ODS3V, 250×4.6 mm, 5 μ) using 50mM KH2PO4 (pH, 5.0) as mobile phase at a flow rate of 1.2 ml/min and temperature of 30°. The wavelength of detection was 254 nm. A retention time of nearly 6 minutes was obtained. Analytical validation parameters such as specificity and selectivity, linearity, accuracy and precision were evaluated. The calibration curve for 5-fluorouracil was linear (r2=0.999±0.0005) from range of 10 μg/ml to 100 μg/ml. Relative standard deviation values for all the key parameters, was less than 2.0 %. The recovery of the drug after standard addition to the degraded sample was found to be 104.69%. Thus, the developed RP-HPLC method was found to be suitable for the determination of 5-fluorouracil in bulk as well as stability samples of the pharmaceutical dosage forms containing various excipients. PMID:20376215

  16. Quantification of malondialdehyde by HPLC-FL - application to various biological samples.

    PubMed

    Domijan, Ana-Marija; Ralić, Jovica; Radić Brkanac, Sandra; Rumora, Lada; Žanić-Grubišić, Tihana

    2015-01-01

    Malondialdehyde (MDA) is stabile product of lipid peroxidation (LPO), and therefore MDA is frequently used as a biomarker of LPO. To determine MDA level in various biological samples (human plasma, fish liver tissue and cells in culture), we used an HPLC method with fluorescent detection based on 2-thiobarbituric acid (TBA) assay. The method was validated by the use of spiked pooled plasma samples. In tested concentration range (0.15-3.0 µmol/L) the method was linear (R(2)  = 0.9963), the between-day variability (coefficient of variations, CVs) was between 4.7 and 7.6%, the within-day variability CVs was between 2.6 and 6.4% and recovery was between 91.2 and 107.6%. The level of MDA in human plasma (healthy male, non-smokers, 46.3 ± 4.7 years; N = 38) was 2.2 ± 1.4 µmol/L; that in liver tissue of common carp (Cyprinus carpio; N = 12) was 0.02 ± 0.004 µmol/g tissue, and in cultured cells (human laryngeal carcinoma cells; N = 10) it was 0.18 ± 0.02 nmol/mg proteins. The HPLC-FL method is rapid, accurate and reliable to follow the extent of LPO in various biological samples, particularly in samples in which a low level of MDA is expected, such as cells in culture. Owing to the rapid analytical process and run time, it can be used for routine analysis of MDA in clinical laboratory. PMID:25355691

  17. Simple isocratic method for simultaneous determination of caffeine and catechins in tea products by HPLC.

    PubMed

    Fernando, Chamira Dilanka; Soysa, Preethi

    2016-01-01

    Tea is a popular beverage almost all over the world. Many studies show that tea consumption is closely associated with positive health impact. Most of the HPLC methods used for the determination of tea constituents include gradient elution systems which involve expensive instrumentation. The objective of this study was to develop a simple, rapid precise and low cost HPLC method for the separation and quantification of catechins and caffeine in tea (Camellia sinensis). The method utilizes a phenyl column (2.1 × 150 mm) with a UV-detector (280 nm) where excellent chromatographic separation of tea components i.e. gallic acid (GA), caffeine (Caf), epicatechin (EC) and (-)-epigallocatechin gallate (EGCG) was achieved. The isocratic elution system of acetonitrile, glacial acetic acid and deionized water (8:1:91 v/v/v) at a flow rate of 0.5 mL/min was involved. This method produced excellent accuracy and precision. Within run and between run precision was less than 7.5 %. The equations for calibration curves were y = 0.117 (±0.010)x + 0.173 (±0.024), y = 0.100 (±0.003)x + 0.045 (±0.019), y = 0.016 (±0.001)x + 0.006 (±0.004), y = 0.025 (±0.001)x-0.025 (±0.007) for GA, Caf, EC and EGCG respectively. The method validation parameters prove that the method is efficient, a simple and adequate for the quantitative determination of principal components in tea samples. PMID:27429880

  18. Determination of rutin and isoquercetin contents in Hibisci mutabilis Folium in different collection periods by HPLC.

    PubMed

    Liu, Diangang; Mei, Qing; Wan, Xiangluan; Que, Hongling; Li, Luyang; Wan, Dingrong

    2015-01-01

    Hibisci mutabilis Folium (HMF), the dried leaf of Hibiscus mutabilis (Malvaceae), is commonly used in traditional Chinese medicine. This article aimed to establish a high-performance liquid chromatography method for the determination of rutin and isoquercitrin contents in the HMF, and to compare the content variation in all the samples, including nearly withered yellow leaf, in different collection periods, so as to provide research basis for the quality evaluation and determination of the optimal collection period. A reversed-phase HPLC separation method was employed, with a BDS Hypersil C18 column (4.6 m × 250 mm, 5 μm), under the following conditions: acetonitrile-0.3% phosphoric acid (15:85, v/v) solution as the mobile phase, flow rate 1.0 mL/min at 30°C and detection wavelength 254 nm. The calibration curves for rutin and isoquercitrin were linear over the range of 1.5-48 and 0.25-8 μg/mL, and the average recoveries were 99.92 and 100.45% (RSD: 2.39% and 2.11%, respectively)]. Based on the analysis results, it was found that contents of rutin and isoquercitrin in HMF (mature green leaf) harvested in different periods had significant difference, and reached the highest in mid-December. It was also found that the contents of the two components in the mature green leaf were much higher than those in the nearly withered leaf from the same collection period. In conclusion, the results indicated that the HPLC method was easy-to-operate and precise, and could be applied for the determination of rutin and isoquercitrin contents in the HMF. The experimental data also showed that early winter should be the most suitable collection period for HMF. PMID:26089170

  19. The Fourth SeaWiFS HPLC Analysis Round-Robin Experiment (SeaHARRE-4)

    NASA Technical Reports Server (NTRS)

    Hooker, Stanford B.; Thomas, Crystal S.; van Heukelem, Laurie; Schlueter, louise; Russ, Mary E.; Ras, Josephine; Claustre, Herve; Clementson, Lesley; Canuti, Elisabetta; Berthon, Jean-Francois; Perl, Jason; Normandeau, Claire; Cullen, John; Kienast, Markus; Pinckney, James L.

    2010-01-01

    Ten international laboratories specializing in the determination of marine pigment concentrations using high performance liquid chromatography (HPLC) were intercompared using in situ samples and a mixed pigment sample. Although prior Sea-viewing Wide Field-of-view Sensor (SeaWiFS) High Performance Liquid Chromatography (HPLC) Round-Robin Experiment (SeaHARRE) activities conducted in open-ocean waters covered a wide dynamic range in productivity, and some of the samples were collected in the coastal zone, none of the activities involved exclusively coastal samples. Consequently, SeaHARRE-4 was organized and executed as a strictly coastal activity and the field samples were collected from primarily eutrophic waters within the coastal zone of Denmark. The more restrictive perspective limited the dynamic range in chlorophyll concentration to approximately one and a half orders of magnitude (previous activities covered more than two orders of magnitude). The method intercomparisons were used for the following objectives: a) estimate the uncertainties in quantitating individual pigments and higher-order variables formed from sums and ratios; b) confirm if the chlorophyll a accuracy requirements for ocean color validation activities (approximately 25%, although 15% would allow for algorithm refinement) can be met in coastal waters; c) establish the reduction in uncertainties as a result of applying QA procedures; d) show the importance of establishing a properly defined referencing system in the computation of uncertainties; e) quantify the analytical benefits of performance metrics, and f) demonstrate the utility of a laboratory mix in understanding method performance. 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.

  20. Characterization of gliclazide release from Isabgol husk hydrogel beads by validated HPLC method.

    PubMed

    Sharma, Vipin K; Mazumdar, B

    2014-01-01

    Isabgol husk, a medicinally important natural polysaccharide was applied for fabrication of hydrogel beads by ionic gelation method to incorporate gliclazide. Different strengths of Isabgol husk and sodium alginate were utilized for assessing the process variables on formulation performance. Aqueous solution of calcium chloride in 2, 5 and 8% w/v strength was used as cross-linker for polymeric blends of Isabgol husk and sodium alginate. The formulations were characterized for various parameters such as particle size, swelling index, entrapment efficiency, in vitro release, and release kinetics. The quantification of gliclazide throughout the study was performed by HPLC method which was validated according to ICH guidelines for system suitability, linearity, accuracy, sensitivity, precession, robustness, and ruggedness. The surface morphology of beads was observed by scanning electron microscopy. The formed beads were brown, free flowing, spherical, and irregular in structure. The size in different formulations varied from 752.83 +/- 0.630 to 838.62 +/- 0.741 microm. The beads remained for 2-3 h in alkaline phosphate buffer (pH 7.4), after that they showed disintegration. The formulations released up to 95% of loaded gliclazide in phosphate buffer (pH 7.4) within 8 h. No significant difference was observed in parameters studied such as particle size, entrapment efficiency and swelling index for hydrogel beads during accelerated stability study (p > 0.05). The regression equation developed by HPLC method was linear (r5 > 0.9990) over the range 2.5 to 10 microg/mL. The limit of detection (LOD) and limit of quantification (LOQ) were 0.037619 microg/mL and 0.113997 microg/mL, respectively. The observed values for number of theoretical plates (N > or = 2000), tailing factor (T < or = 2), asymmetry factor (AF < or = 1), and relative standard deviation (RSD < or = 1%) of applied method showed the reliability for gliclazide estimation in Isabgol husk hydrogel beads. PMID

  1. Biodistribution study of free and microencapsulated 6-methylcoumarin in Wistar rats by HPLC.

    PubMed

    Hernández, Aura Rocío; Ospina, Luis Fernando; Aragón, Diana Marcela

    2015-02-01

    A sensitive, specific and reproducible HPLC method has been developed and validated for the quantitative determination of 6-methylcoumarin (6MC) in plasma and other tissues in Wistar rats. A C18 column was used with UV detection at 321 nm and a gradient system consisting of methanol-deionized water was used as mobile phase. The retention time for 6MC was 14.921 min and no interfering peaks were observed for any of the matrices. Linear relationships (r(2)  > 0.997) were obtained between the peak height ratios and the corresponding biological sample concentrations over the range 0.4-12.8 µg/mL. Precision and accuracy were evaluated; the coefficient of variation and the relative error for all of the organs were <2 and 7%, respectively. The limit of quantitation was 0.20 µg/mL for the heart and 0.30 µg/mL for the other tissues evaluated. This HPLC method was successfully used in the determination of 6MC in the biodistribution study after administration of 200 mg/kg of both 6MC-free and 6MC-loaded polymeric microparticles. In this study, extensive 6MC was found, in both free and microencapsulated forms, in all the organs tested. The 6MC-free showed a range of between 1.7 and 11.5 µg/g, while the microencapsulated 6MC showed concentrations of between 6.35 and 17.7 µg/g, suggesting that 6MC improved absorption rate. PMID:24854221

  2. Improved quality control of [18F]FDG by HPLC with UV detection.

    PubMed

    Nakao, Ryuji; Ito, Takehito; Yamaguchi, Masatoshi; Suzuki, Kazutoshi

    2005-11-01

    A conventional high-performance liquid chromatographic (HPLC) method for the analysis of 2-fluoro-2-deoxy-d-glucose (FDG) and 2-deoxy-2-chloro-d-glucose (ClDG) in [18F]FDG preparations is described. This method was based on a postcolumn derivatization with 2-cyanoacetamide (2-CA) and UV detection. FDG and ClDG were separated on a normal-phase column using acetonitrile/water as the mobile phase. The eluate was mixed with 2-CA in sodium borate buffer solution at the outlet of a PTFE coil (10 m x 0.5 mm id) from the column, and the reaction was carried out at 100 degrees C during the passage through the coil. The UV absorbance of the resultant product was monitored at 276 nm. Under optimum conditions, the detection limits [signal-to-noise (S/N) ratio=3] for FDG and ClDG were 0.31 and 0.17 microg/ml for a 20-microl injection volume, respectively, and the linearity ranges were 0.5-100 microg/ml for both compounds. The intra- and interday reproducibilities were better than 2.2% [relative standard deviation (R.S.D.)]. This HPLC separation procedure is also useful for determining the radiochemical purity of [18F]FDG preparations since it allows the analysis of 2-[18F]fluoro-1,3,4,6-tetra-O-acetyl-d-glucose ([18F]TAG), partially hydrolyzed [18F]TAG and [18F]F-. This method can be used at many positron emission tomography (PET) facilities since it does not require an expensive, sophisticated electrochemical detector. PMID:16253817

  3. Comparison of HPLC-MS interfaces in the determination of heterocyclic polycyclic aromatic compounds

    SciTech Connect

    Thomas, D.; Sim, P.G.; Benoit, F.M.

    1995-12-31

    Polycyclic aromatic compounds (PACs) are generally regarded as one of the most widely disseminated groups of chemical carcinogens. In this work, the authors are interested in the determination of some of the heteroatom substituted PACs, particularly those containing nitrogen (PANHs) or sulfur (PASHs) in the aromatic ring structure. The reason for interest in these compounds is the extreme carcinogenicity of many of them. Further, the relative carcinogenicity can vary markedly between different members of a set of isomeric compounds. Any reliable assessment of the hazards associated with exposure to mixtures of PACs must, therefore, include analysis of the levels of these compounds in the mixture. The analytical technique used must also yield information about the relative amounts of different isomeric compounds. The sample chosen for this study is an extract of PACs from the Sydney Tar Ponds, Sydney, Nova Scotia, Canada. The Tar Ponds represent the end result of approximately 80 years of the uncontrolled discharge of effluent from an industrial coking operation into a tidal lagoon. It is thus a rich source of PAC mixtures. In the present work, the authors have applied two HPLC-MS methods to the characterization of the PASH content of tar pond sample fractions. The methods differed in the nature of the interface between the HPLC and the MS, and in the ionization process. The two techniques studied were the moving belt with EI ionization, and the heated nebulizer with APCI. Comparison was made on the basis of a number of criteria, including ease of use (and of automation), quality of mass spectra provided, preservation of chromatographic integrity, and sensitivity.

  4. Complementarity of UV-PLS and HPLC for the simultaneous evaluation of antiemetic drugs.

    PubMed

    Bourdon, F; Lecoeur, M; Odou, P; Vaccher, C; Foulon, C

    2014-03-01

    This work was dedicated to the development of a simple and direct multivariate UV spectrophotometric method for the simultaneous determination of three antiemetic drugs (ondansetron, dexamethasone and aprepitant) in a new organogel formulation developed for their simultaneous transdermal administration. This method that does not require separation of the drugs and sophisticated instrument will permit to control quality of this new transdermal form both during the optimization step and for a further routine control of this preparation at the pharmacy department of the hospital. Hence, a partial least squares regression model using the spectral data record from 260 to 288 nm and 5 components, has firstly been validated thanks to the evaluation of the REP% (under 7.9%) and secondly using an accuracy profile approach (acceptance limit of ±10%). Thereby, the method allows the quantitation of the drugs in the ranges (5-15 mg L(-1)), (4-8 mg L(-1)) and (20-50 mg L(-1)) for ondansetron, dexamethasone and aprepitant, respectively. An HPLC/UV reference method has also been developed. Optimal separation (2.52HPLC/UV method will be in favor of its use for permeation studies. PMID:24468370

  5. HPLC-FLD determination of 4-nonylphenol and 4-tert-octylphenol in surface water samples.

    PubMed

    Cruceru, Ioana; Iancu, Vasile; Petre, Jana; Badea, Irinel Adriana; Vladescu, Luminita

    2012-05-01

    A simple, sensitive and reliable HPLC-FLD method for the routine determination of 4-nonylphenol, 4-NP and 4-tert-octylphenol, 4-t-OP content in water samples was developed. The method consists in a liquid-liquid extraction of the target analytes with dichloromethane at pH  3.0-3.5 followed by the HPLC-FLD analysis of the organic extract using a Zorbax Eclipse XDB C8 column, isocratic elution with a mixed solvent acetonitrile/water 65:35, at a flow rate of 1.0 mL/min and applying a column temperature of 40°C. The method was validated and then applied with good results for the determination of 4-NP and 4-t-OP in Ialomiţa River water samples collected each month during 2006. The concentration levels of 4-NP and 4-t-OP vary between 0.08-0.17 μg/L with higher values of 0.24-0.37 μg/L in the summer months for 4-NP, and frequently <0.05 μg/L but also between 0.06-0.09 μg/L with higher values of 0.12-0.16 μg/L in July and August for 4-t-OP and were strongly influenced by sesonial and anthropic factors. The method was also applied on samples collected over 2 years 2007 and 2008 from urban wastewaters discharged into sewage or directly into the rivers by economic agents located in 30 Romanian towns. Good results were obtained when the method was used for analysis of effluents discharged into surface waters by 16 municipal wastewater treatment plants, during the year 2008. PMID:21688033

  6. Simple Isocratic HPLC Method for Determination of Enantiomeric Impurity in Besifloxacin Hydrochloride.

    PubMed

    Kumar, G Pradeep; Srivastava, Vishal; Khandelwal, Kiran; Kumar, Rajesh; Hiriyanna, S G; Kumar, Ajay; Kumar, Pramod

    2016-09-01

    Besifloxacin is a unique chiral broad-spectrum flouroquinolone used in the treatment of bacterial conjunctivitis. R-form of besifloxacin hydrochloride shows higher antibacterial activity as compared to the S-isomer. Therefore, it is necessary to establish chiral purity. To establish chiral purity a high-performance liquid chromatography (HPLC) method for determination of R-besifloxacin and S-besifloxacin (BES impurity A) was developed and validated for in-process quality control and stability studies. The analytical performance parameters such as linearity, precision, accuracy, specificity, limit of detection (LOD), and lower limit of quantification (LOQ) were determined according to International Council for Harmonization ICH Q2(R1) guidelines. HPLC separation was achieved on Chiralpak AD-H (250 x 4.6 mm, 5 μm) column using n-heptane: ethanol: ethylenediamine: acetic acid (800:200:0.5:0.5) (v/v/v/v) as the mobile phase in an isocratic elution. The eluents were monitored by UV/Visible detector at 290 nm. The resolution between S-isomer and besifloxacin hydrochloride was more than 2.0. Based on a signal-to-noise ratio of 3 and 10 the LOD of besifloxacin was 0.30 μg/mL, while the LOQ was 0.90 μg/mL. The calibration curves were linear in the range of 0.9-7.5 μg/mL. Precision of the method was established within the acceptable range. The method was suitable for the quality control enantiomeric impurity in besifloxacin hydrochloride. Chirality 28:628-632, 2016. © 2016 Wiley Periodicals, Inc. PMID:27563753

  7. Phosphorus speciation by coupled HPLC-ICPMS: low level determination of reduced phosphorus in natural materials

    NASA Astrophysics Data System (ADS)

    Atlas, Zachary; Pasek, Matthew; Sampson, Jacqueline

    2015-04-01

    Phosphorus is a geologically important minor element in the Earth's crust commonly found as relatively insoluble apatite. This constraint causes phosphorus to be a key limiting nutrient in biologic processes. Despite this, phosphorus plays a direct role in the formation of DNA, RNA and other cellular materials. Recent works suggest that since reduced phosphorus is considerably more soluble than oxidized phosphorus that it was integrally involved in the development of life on the early Earth and may continue to play a role in biologic productivity to this day. This work examines a new method for quantification and identification of reduced phosphorus as well as applications to the speciation of organo-phosphates separated by coupled HPLC - ICP-MS. We show that reduced phosphorus species (P1+, P3+ and P5+) are cleanly separated in the HPLC and coupled with the ICPMS reaction cell, using oxygen as a reaction gas to effectively convert elemental P to P-O. Analysis at M/Z= 47 producing lower background and flatter baseline chromatography than analyses performed at M/Z = 31. Results suggest very low detection limits (0.05 μM) for P species analyzed as P-O. Additionally we show that this technique has potential to speciate at least 5 other forms of phosphorus compounds. We verified the efficacy of method on numerous materials including leached Archean rocks, suburban retention pond waters, blood and urine samples and most samples show small but detectible levels of reduced phosphorus and or organo-phaospates. This finding in nearly all substances analyzed supports the assumption that the redox processing of phosphorus has played a significant role throughout the history of the Earth and it's presence in the present environment is nearly ubiquitous with the reduced oxidation state phosphorus compounds, phosphite and hypophosphite, potentially acting as significant constituents in the anaerobic environment.

  8. Post column derivatisation analyses review. Is post-column derivatisation incompatible with modern HPLC columns?

    PubMed

    Jones, Andrew; Pravadali-Cekic, Sercan; Dennis, Gary R; Shalliker, R Andrew

    2015-08-19

    Post Column derivatisation (PCD) coupled with high performance liquid chromatography or ultra-high performance liquid chromatography is a powerful tool in the modern analytical laboratory, or at least it should be. One drawback with PCD techniques is the extra post-column dead volume due to reaction coils used to enable adequate reaction time and the mixing of reagents which causes peak broadening, hence a loss of separation power. This loss of efficiency is counter-productive to modern HPLC technologies, -such as UHPLC. We reviewed 87 PCD methods published from 2009 to 2014. We restricted our review to methods published between 2009 and 2014, because we were interested in the uptake of PCD methods in UHPLC environments. Our review focused on a range of system parameters including: column dimensions, stationary phase and particle size, as well as the geometry of the reaction loop. The most commonly used column in the methods investigated was not in fact a modern UHPLC version with sub-2-micron, (or even sub-3-micron) particles, but rather, work-house columns, such as, 250 × 4.6 mm i.d. columns packed with 5 μm C18 particles. Reaction loops were varied, even within the same type of analysis, but the majority of methods employed loop systems with volumes greater than 500 μL. A second part of this review illustrated briefly the effect of dead volume on column performance. The experiment evaluated the change in resolution and separation efficiency of some weak to moderately retained solutes on a 250 × 4.6 mm i.d. column packed with 5 μm particles. The data showed that reaction loops beyond 100 μL resulted in a very serious loss of performance. Our study concluded that practitioners of PCD methods largely avoid the use of UHPLC-type column formats, so yes, very much, PCD is incompatible with the modern HPLC column. PMID:26343427

  9. Stability-indicating HPLC Method for Simultaneous Determination of Terbutaline Sulphate, Bromhexine Hydrochloride and Guaifenesin.

    PubMed

    Porel, A; Haty, Sanjukta; Kundu, A

    2011-01-01

    The aim of the present study was the development and subsequent validation of a simple, precise and stability-indicating reversed phase HPLC method for the simultaneous determination of guaifenesin, terbutaline sulphate and bromhexine hydrochloride in the presence of their potential impurities in a single run. The photolytic as well as hydrolytic impurities were detected as 3,5-dihydroxybenzoic acid, 3,5-dihydroxybenzaldehyde, 1-(3,5-dihydroxyphenyl)-2-[(1,1-dimethylethyl) amino]-ethanone from terbutaline, 2-methoxyphenol and an unknown impurity identified as (2RS)-3-(2-hydroxyphenoxy)-propane-1,2-diol from guaifenesin. The chromatographic separation of all the three active components and their impurities was achieved on Wakosil II column, using phosphate buffer (pH 3.0) and acetonitrile as mobile phase which was delivered initially in the ratio of 80:20 (v/v) for 18 min, then changed to 60:40 (v/v) for next 12 min, and finally equilibrated back to 80:20 (v/v) for 10 min. Other HPLC parameters were: Flow rate at 1.0 ml/min, detection wavelengths 248 and 280 nm, injection volume 10 μl. The calibration graphs plotted with five concentrations of each component were linear with a regression coefficient R(2) >0.9999. The limit of detection and limit of quantitation were estimated for all the five impurities. The established method was then validated for linearity, precision, accuracy, and specificity and demonstrated to be applicable to the determination of the active ingredients in commercial and model cough syrup. No interference from the formulation excipients was observed. These results suggest that this LC method can be used for the determination of multiple active ingredients and their impurities in a cough and cold syrup. PMID:22131621

  10. Validation of analytical procedures using HPLC-ELSD to determine six sesquiterpene lactones in Eremanthus species.

    PubMed

    Sousa, João Paulo B; Nogueira, Elídia F; Ferreira, Leandro S; Lopes, Norberto P; Lopes, João Luis C

    2016-03-01

    Eremanthus species display sesquiterpene lactones with therapeutic potential. We are proposing the development of a new analytical method that has been completely validated to qualify Eremanthus species and its main lactones in raw material using HPLC-ELSD. For the sample preparation, 10.0 mg of powdered Eremanthus leaves was extracted with a 5 mL MeOH/H2 O (9:1 v/v) solution containing scopoletin at 140 µg/mL as the internal standard. For the separation of eight compounds, six of which were lactones, one internal (IS) and one secondary standard were performed utilizing monolithic columns with a nonlinear gradient. The selectivity, stability, precision and matrix effects parameters showed values of RSD of <10%. The six lactones and scopoletin (IS) were recovered with a proportion between 74 and 90% with accuracy represented by error at -25.41%. The linear dynamic range was obtained between 10.0 and 310.0 µg/mL for all compounds with r(2)  > 0.9987. The limits of detection and quantitation ranged from 2.00 to 6.79 µg/mL and from 6.00 to 20.40 µg/mL, respectively. Assessing the robustness study, this method can be used in inter-laboratory studies. Using the HPLC-ELSD method, six sesquiterpene lactones including 4β,5-dihydro-2',3'-dihydroxy-15-deoxy-goyazensolide, goyazensolide, 4β,5-dihydro-2',3'-epoxy-15-deoxy-goyazensolide, centratherin, 4β,5-dihydro-15-deoxy-goyazensolide and lychnofolide, were detected and quantified from distinct Eremanthus species, which were collected in different regions. PMID:26234655

  11. Single dose pharmacokinetics of atorvastatin oral formulations using a simple HPLC-UV method.

    PubMed

    Sohail, Muhammad; Ahmad, Mahmood; Minhas, Muhammad Usman

    2016-07-01

    The study was aimed to assess pharmacokinetics of atorvastatin (40 mg) in healthy fasted human subjects by a simple and inexpensive high performance liquid chromatography. Experimental design of the study was a randomized, two way, two periods, crossover study (single dose in fasted conditions). Eighteen (18) healthy male volunteers were enrolled according to FDA guidelines. The plasma samples were assayed using an isocratic High Performance Liquid Chromatography (HPLC) system of Agilent technologies USA consisted of an isocratic pump with column of Thermo Electron Corporation USA (ODS hypersil C(18) 4.6 mm x 250 mm), a UV-visible detector set at λ(max) 237 nm. Maximum plasma concentrations (C(max)) of atorvastatin (Mean ± SEM) for the reference product (A) found to be 13.739±0.210ng/ml & 13.374±0.145ng/ml for test product (B). T(max) values (Mean±SEM) of atorvastatin were 1.222 ±0.060 hours and 1.167±0.057 hours for reference and test products, respectively. The values of AUC(0-oo) (Mean ± SEM) for the reference (A) and test product (B) were 73.955 ± 1.715ng.h/ml and 77.773 ± 1.858ng. h/ml, respectively. Other pharmacokinetic parameters of both products were also determined. A statistical non-significant difference between pharmacokinetic parameters has been found and both brands of atorvastatin showed the same rate and extent of absorption in healthy fasted human volunteers after single dose. A simple and cost effective HPLC method was developed and applied. PMID:27393428

  12. Antineoplastic drugs determination by HPLC-HRMS(n) to monitor occupational exposure.

    PubMed

    Dal Bello, Federica; Santoro, Valentina; Scarpino, Valentina; Martano, Chiara; Aigotti, Riccardo; Chiappa, Alberta; Davoli, Enrico; Medana, Claudio

    2016-07-01

    The purpose of this study was to develop a simple, direct, multiresidue highly specific procedure to evaluate the possible surface contamination of selected antineoplastic drugs in several hospital environment sites by using wipe test sampling. 5-fluorouracil (5-FU), carboplatin (C-Pt), cyclophosphamide (CYC), cytarabine (CYT), doxorubicin (DOX), gemcitabine (GEM), ifosfamide (IFO), methotrexate (MET), and mitomycin C (MIT) belong to very different chemical classes but show good ionization properties under electrospray ionization (ESI) conditions (negative ion mode for 5-FU and positive ion mode in all other cases). HPLC (high performance liquid chromatography) coupled with HRMS (high resolution mass spectrometry) appears to be the best technique for direct analysis of these analytes, because neither derivatization nor complex extraction procedure for polar compounds in samples is requested prior the analysis. Sample preparation was limited to washing wipes with appropriate solvents. Chromatographic separation was achieved on C18 reversed phase columns. The HPLC-HRMS/MS method was validated in order to obtain robustness, sensitivity and selectivity. LLOQ (lower limit of quantitation) values provided a sensitivity good enough to evidence the presence of the drugs in a very low concentration range (<1 pg/cm(2) ). The method was applied for a study of real wipe tests coming from many areas from a hospital showing some positive samples. The low quantitation limits and the high specificity due to the high resolution approach of the developed method allowed an accurate description of the working environment that can be used to define procedural rules to limit working place contamination to a minimum. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26041114

  13. Fingerprint analysis and multi-component determination of Zibu Piyin recipe by HPLC with DAD and Q-TOF/MS method.

    PubMed

    Xiang, Hong; Xu, Huiying; Zhan, Libin; Zhang, Lin

    2016-05-01

    Zibu Piyin recipe (ZBPYR), a traditional Chinese medicine formula, is used for curing dementia caused by diabetes. For quality control of ZBPYR, fingerprint analysis and qualitative analysis using high-performance liquid chromatography (HPLC) with a diode-array detector, and confirmation using HPLC coupled with electrospray ionisation quadrupole time-of-flight tandem mass spectrometry (HPLC-Q-TOF-MS) were undertaken. HPLC fingerprint consisting of 34 common peaks was developed among 10 batches of ZBPYR, in which 7 common peaks were identified in comparison with the authentic standards and detected simultaneously. Furthermore, these seven compounds were verified by HPLC-Q-TOF-MS methods. The method can be applied to the quality control of ZBPYR. PMID:26418623

  14. AN IMPROVED HPLC-MS/MS METHOD FOR DETERMINATION OF ISOXAFLUTOLE (BALANCE) AND ITS METABOLITES IN SOILS AND FORAGE PLANTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An analytical method using turbo-spray and heat-nebulizer high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed for the analysis of isoxaflutole (IXF) and its two metabolites, diketonitrile (DKN) and the benzoic acid metabolite (BA), at sub 'g/kg levels in soil a...

  15. USE OF CYANOPROPYL-BONDED HPLC COLUMN FOR BIOASSAY-DIRECTED FRACTIONATION OF ORGANIC EXTRACTS FROM INCINERATOR EMISSIONS

    EPA Science Inventory

    The present study has shown that cyanopropyl-(CN) bonded silica HPLC columns are applicable for the fractionation of mass and mutagenic activity of organic extracts from some incinerator emissions. ichloromethane-extractable organics from particles emitted by two different munici...

  16. Quantification of Arsenolipids in the Certified Reference Material NMIJ 7405-a (Hijiki) using HPLC/Mass Spectrometry after Chemical Derivatization

    PubMed Central

    2014-01-01

    Arsenic-containing lipids (arsenolipids) are novel natural products recently shown to be widespread in marine animals and algae. Research interest in these arsenic compounds lies in their possible role in the membrane chemistry of organisms and, because they occur in many popular seafoods, their human metabolism and toxicology. Progress has been restricted, however, by the lack of standard arsenolipids and of a quantitative method for their analysis. We report that the certified reference material CRM 7405-a (Hijiki) is a rich source of arsenolipids, and we describe a method based on HPLC-ICPMS/ESMS to quantitatively measure seven of the major arsenolipids present. Sample preparation involved extraction with DCM/methanol, a cleanup step with silica, and conversion of the (oxo)arsenolipids originally present to thio analogues by brief treatment with H2S. Compared to their oxo analogues, the thioarsenolipids showed much sharper peaks on reversed-phase HPLC, which facilitated their resolution and quantification. The compounds were determined by HPLC-ICPMS and HPLC-ESMS, which provided both arsenic-selective detection and high resolution molecular mass detection of the arsenolipids. In this way, the concentrations of two arsenic-containing hydrocarbons and five arsenosugar phospholipids are reported in the CRM Hijiki. This material may serve as a convenient source of characterized arsenolipids to delineate the presence of these compounds in seafoods and to facilitate research in a new era of arsenic biochemistry. PMID:25241916

  17. Quantification of arsenolipids in the certified reference material NMIJ 7405-a (Hijiki) using HPLC/mass spectrometry after chemical derivatization.

    PubMed

    Glabonjat, Ronald A; Raber, Georg; Jensen, Kenneth B; Ehgartner, Josef; Francesconi, Kevin A

    2014-10-21

    Arsenic-containing lipids (arsenolipids) are novel natural products recently shown to be widespread in marine animals and algae. Research interest in these arsenic compounds lies in their possible role in the membrane chemistry of organisms and, because they occur in many popular seafoods, their human metabolism and toxicology. Progress has been restricted, however, by the lack of standard arsenolipids and of a quantitative method for their analysis. We report that the certified reference material CRM 7405-a (Hijiki) is a rich source of arsenolipids, and we describe a method based on HPLC-ICPMS/ESMS to quantitatively measure seven of the major arsenolipids present. Sample preparation involved extraction with DCM/methanol, a cleanup step with silica, and conversion of the (oxo)arsenolipids originally present to thio analogues by brief treatment with H2S. Compared to their oxo analogues, the thioarsenolipids showed much sharper peaks on reversed-phase HPLC, which facilitated their resolution and quantification. The compounds were determined by HPLC-ICPMS and HPLC-ESMS, which provided both arsenic-selective detection and high resolution molecular mass detection of the arsenolipids. In this way, the concentrations of two arsenic-containing hydrocarbons and five arsenosugar phospholipids are reported in the CRM Hijiki. This material may serve as a convenient source of characterized arsenolipids to delineate the presence of these compounds in seafoods and to facilitate research in a new era of arsenic biochemistry. PMID:25241916

  18. 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…

  19. FISH BILIARY POLYCYCLIC AROMATIC HYDROCARBON METABOLITES ESTIMATED BY FIXED-WAVELENGTH FLUORESCENCE: COMPARISON WITH HPLC-FLUORESCENT DETECTION

    EPA Science Inventory

    Fixed wavelength fluorescence (FF) was compared to high-performance liquid chromatography with fluorescence detection (HPLC-F) as an estimation of polycyclic aromatic hydrocarbon (PAH) exposure to fish. Two excitation/emission wavelength pairs were used to measure naphthalene- an...

  20. Automated solid-phase extraction coupled online with HPLC-FLD for the quantification of zearalenone in edible oil.

    PubMed

    Drzymala, Sarah S; Weiz, Stefan; Heinze, Julia; Marten, Silvia; Prinz, Carsten; Zimathies, Annett; Garbe, Leif-Alexander; Koch, Matthias

    2015-05-01

    Established maximum levels for the mycotoxin zearalenone (ZEN) in edible oil require monitoring by reliable analytical methods. Therefore, an automated SPE-HPLC online system based on dynamic covalent hydrazine chemistry has been developed. The SPE step comprises a reversible hydrazone formation by ZEN and a hydrazine moiety covalently attached to a solid phase. Seven hydrazine materials with different properties regarding the resin backbone, pore size, particle size, specific surface area, and loading have been evaluated. As a result, a hydrazine-functionalized silica gel was chosen. The final automated online method was validated and applied to the analysis of three maize germ oil samples including a provisionally certified reference material. Important performance criteria for the recovery (70-120 %) and precision (RSDr <25 %) as set by the Commission Regulation EC 401/2006 were fulfilled: The mean recovery was 78 % and RSDr did not exceed 8 %. The results of the SPE-HPLC online method were further compared to results obtained by liquid-liquid extraction with stable isotope dilution analysis LC-MS/MS and found to be in good agreement. The developed SPE-HPLC online system with fluorescence detection allows a reliable, accurate, and sensitive quantification (limit of quantification, 30 μg/kg) of ZEN in edible oils while significantly reducing the workload. To our knowledge, this is the first report on an automated SPE-HPLC method based on a covalent SPE approach. PMID:25709066

  1. 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. PMID:24310099

  2. Analysis of Piperaceae germplasm by HPLC and LCMS: a method for isolating and identifying unsaturated amides from Piper spp extracts.

    PubMed

    Scott, Ian M; Puniani, Evaloni; Jensen, Helen; Livesey, John F; Poveda, Luis; Sanchez-Vindas, Pablo; Durst, Tony; Arnason, John T

    2005-03-23

    A method for extraction and high performance liquid chromatography-mass spectrometer (HPLC-MS) analysis of the medicinally important genus Piper (Piperaceae) was developed. This allows for a rapid and accurate measure of unsaturated amides, or piperamides, in black pepper, Piper nigrum L., and in wild species from Central America. Reflux extraction provided the highest recovery of piperine (>80%) from leaf and peppercorn material. HPLC analysis using a binary gradient of acetonitrile and water separated the major amide peaks between 5 and 12 min. Atmospheric pressure chemical ionization (APCI)-MS improved the detection limit to 0.2 ng, 10-fold below the 2 ng limit of the HPLC-diode array detector (DAD) based on linear standard curves between 0.1 and 250 microg/mL (R2 = 0.999). The HPLC-MS method identified pellitorine, piperylin, 4,5-dihydropiperlonguminine, piperlonguminine, 4,5-dihydropiperine, piperine, and pipercide. The biological activity of six Costa Rican Piper species assessed by mosquito larval bioassays correlated well with piperamide content. PMID:15769112

  3. Efficient HPLC method development using structure-based database search, physico-chemical prediction and chromatographic simulation.

    PubMed

    Wang, Lin; Zheng, Jinjian; Gong, Xiaoyi; Hartman, Robert; Antonucci, Vincent

    2015-02-01

    Development of a robust HPLC method for pharmaceutical analysis can be very challenging and time-consuming. In our laboratory, we have developed a new workflow leveraging ACD/Labs software tools to improve the performance of HPLC method development. First, we established ACD-based analytical method databases that can be searched by chemical structure similarity. By taking advantage of the existing knowledge of HPLC methods archived in the databases, one can find a good starting point for HPLC method development, or even reuse an existing method as is for a new project. Second, we used the software to predict compound physicochemical properties before running actual experiments to help select appropriate method conditions for targeted screening experiments. Finally, after selecting stationary and mobile phases, we used modeling software to simulate chromatographic separations for optimized temperature and gradient program. The optimized new method was then uploaded to internal databases as knowledge available to assist future method development efforts. Routine implementation of such standardized workflows has the potential to reduce the number of experiments required for method development and facilitate systematic and efficient development of faster, greener and more robust methods leading to greater productivity. In this article, we used Loratadine method development as an example to demonstrate efficient method development using this new workflow. PMID:25481084

  4. RP-HPLC Determination of Phenylalkanoids and Monoterpenoids in Rhodiola rosea and Identification by LC-ESI-TOF

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An HPLC method permitting the simultaneous determination of fourteen compounds (phenylalkanoids and monoterpenoids) from the roots of Rhodiola rosea was developed. A separation was achieved within 35 minutes by using C-18 column material, a water/acetonitrile mobile phase, both containing 0.05% phos...

  5. Relationships of Quality Characteristics with Size Exclusion HPLC Chromatogram of Protein Extract in Soft-White Winter Wheats.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study investigated relationships between molecular weight distributions of unreduced grain proteins and grain, flour, and end-use quality characteristics of soft white winter wheats grown in Oregon. Absorbance area and area % values of protein fractions separated by size exclusion HPLC (SE-HPL...

  6. Anion Exchange HPLC Isolation of High-Density Lipoprotein (HDL) and On-Line Estimation of Proinflammatory HDL

    PubMed Central

    Ji, Xiang; Xu, Hao; Zhang, Hao; Hillery, Cheryl A.; Gao, Hai-qing; Pritchard, Kirkwood A.

    2014-01-01

    Proinflammatory high-density lipoprotein (p-HDL) is a biomarker of cardiovascular disease. Sickle cell disease (SCD) is characterized by chronic states of oxidative stress that many consider to play a role in forming p-HDL. To measure p-HDL, apolipoprotein (apo) B containing lipoproteins are precipitated. Supernatant HDL is incubated with an oxidant/LDL or an oxidant alone and rates of HDL oxidation monitored with dichlorofluorescein (DCFH). Although apoB precipitation is convenient for isolating HDL, the resulting supernatant matrix likely influences HDL oxidation. To determine effects of supernatants on p-HDL measurements we purified HDL from plasma from SCD subjects by anion exchange (AE) chromatography, determined its rate of oxidation relative to supernatant HDL. SCD decreased total cholesterol but not triglycerides or HDL and increased cell-free (cf) hemoglobin (Hb) and xanthine oxidase (XO). HDL isolated by AE-HPLC had lower p-HDL levels than HDL in supernatants after apoB precipitation. XO+xanthine (X) and cf Hb accelerated purified HDL oxidation. Although the plate and AE-HPLC assays both showed p-HDL directly correlated with cf-Hb in SCD plasma, the plate assay yielded p-HDL data that was influenced more by cf-Hb than AE-HPLC generated p-HDL data. The AE-HPLC p-HDL assay reduces the influence of the supernatants and shows that SCD increases p-HDL. PMID:24609013

  7. 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.

  8. Analysis of alkylresorcinols in wheat germ oil and barley germ oil via HPLC and flourescence detection: Cochromatography with tocols

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alkylresorcinols are long chain phenolic compounds that have been reported to be localized in the outer layers of the kernels of wheat, rye, barley and other grains. A sensitive HPLC method with fluorescence detection was recently reported for the quantitative analysis of alkylresorcinols in cereal...

  9. A simple HPLC method for the isolation and quantification of the allergens tuliposide A and tulipalin A in Alstroemeria.

    PubMed

    Christensen, L P; Kristiansen, K

    1995-04-01

    A practical, rapid, reliable and sensitive method for the isolation and determination of the allergens tuliposide A and alpha-methylene-gamma-butyrolactone (tulipalin A), by reversed-phase high-performance liquid chromatography (RP-HPLC), has been developed in order to select Alstroemeria species for breeding purposes. From the aqueous extracts of flowers, stems and leaves, of several Alstroemeria species, the contents of 6-tuliposide A and tulipalin A were determined by isocratic RP-HPLC, using distilled water as mobile phase. The compounds were detected by an UV detector at 208 nm. Differences in 6-tuliposide A and tulipalin A content were found among the species investigated, with the highest concentrations in stems and flowers. The absence of other tuliposides (e.g., 1-tuliposide A, 1- and 6-tuliposide B) in extracts was proven by TLC, RP-HPLC, 1H- and 13C-NMR. 6-Tuliposide A and tulipalin A were identified by 1H- and 13C-NMR and comparison with authentic material, respectively. With this HPLC method, it is possible to investigate a large number of plants for their contents of tuliposide A and tulipalin A, within a minimum of time, and to isolate them directly from aqueous extracts. PMID:7600774

  10. Characterization of zebrafish cardiac proteome using online pH gradient SCX-RP HPLC-MS/MS platform.

    PubMed

    Zhang, Jiang; Lanham, Kevin A; Heideman, Warren; Peterson, Richard E; Li, Lingjun

    2013-01-01

    Two-dimensional HPLC coupled with tandem MS (MS/MS) has become a mainstream technique in the shotgun proteomics for large-scale identification of proteins from biological samples. This powerful technology provides speed, sensitivity, and dynamic range which are essential to probe complex peptide mixtures from proteomic samples. Herein we present a pH gradient SCX-RP 2D HPLC-MS/MS method designed to improve the peptide resolution and protein identification from complex proteomic samples. The comparison between the pH gradient SCX-RP 2D HPLC method and traditional salt gradient SCX-RP method was presented. A two-step sample prefractionation method utilizing microwave-assisted tryptic digestion to improve the identification of insoluble proteins was also introduced. This novel 2D HPLC-MS/MS method was applied to the heart proteomic sample of the zebrafish, Danio rerio, to provide comprehensive cardiac proteomic profiling of this important model organism for cardiovascular and environmental toxicology studies. PMID:23606253

  11. Application of on-line HPLC-1H NMR to environmental samples: analysis of groundwater near former ammunition plants.

    PubMed

    Godejohann, M; Preiss, A; Mügge, C; Wünsch, G

    1997-09-15

    Coupling of HPLC to NMR was applied for the first time to the analysis of environmental samples, i.e., water samples from an ammunition hazardous waste site. Using the continuous flow mode at very low flow rates (< or = 0.017 mL/min) and large volume injection (400 microL), the confirmation of many nitroaromatic compounds could be achieved down to the microgram-per-liter level after solid phase extraction of a groundwater sample from a former ammunition production site. At a flow rate of 0.006 mL/min, it is possible to detect less than 29 nmol (5 micrograms) of 1,3-dinitrobenzene injected on a 75 mm x 4 mm reversed phase C-18 column (particle size, 5 microns). The results obtained by HPLC-NMR are compared to those obtained by HPLC-PDA (photodiode array) of the same sample, demonstrating that many more compounds can be identified by the former compared to the latter method as a result of coelution of major and minor components in the HPLC chromatogram. PMID:9302876

  12. HPLC Determination and MS Confirmation of Malachite Green, Gentian Violet, and Their Leuco Metabolites in Catfish Muscle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Residues of malachite green (MG), gentian violet (GV), and their leuco metabolites in catfish muscle were individually determined by HPLC using visible and fluorescence detectors. This detection scheme obviated a PbO2 column that converts leuco forms to chromatic forms for visible detection, thus el...

  13. Stability-Indicating RP-HPLC Method for the Determination of Ambrisentan and Tadalafil in Pharmaceutical Dosage Form

    PubMed Central

    Patel, Jayvadan K.; Patel, Nilam K.

    2014-01-01

    Abstract A simple, rapid, and highly selective RP-HPLC method was developed for the simultaneous determination of Ambrisentan (AMB) and Tadalafil (TADA) drug substances in the fixed dosage strength of 10 mg and 40 mg, respectively. Effective chromatographic separation was achieved using a Hypersil GOLD C18 column (150 mm × 4.6 mm internal diameter, 5 μm particle size) with a mobile phase composed of methanol, water, and acetonitrile in the ratio of 40:40:20 (by volume). The mobile phase was pumped using a gradient HPLC system at a flow rate of 0.5 mL/min, and quantification of the analytes was based on measuring their peak areas at 260 nm. The retention times for Ambrisentan and Tadalafil were about 2.80 and 7.10 min, respectively. The reliability and analytical performance of the proposed HPLC procedure were statistically validated with respect to system suitability, linearity, ranges, precision, accuracy, specificity, robustness, detection, and quantification limits. Calibration curves were linear in the ranges of 1–20 μg/mL for Ambrisentan and 4–80 μg/mL for Tadalafil with correlation coefficients >0.990. The proposed method proved to be selective and stability-indicating by the resolution of the two analytes from the forced degradation (hydrolysis, oxidation, and photolysis) products. The validated HPLC method was successfully applied to the analysis of AMB and TADA in pharmaceutical dosage form. PMID:26279975

  14. Preparation and Characterization of a Polymeric Monolithic Column for Use in High-Performance Liquid Chromatography (HPLC)

    ERIC Educational Resources Information Center

    Bindis, Michael P.; Bretz, Stacey Lowery; Danielson, Neil D.

    2011-01-01

    The high-performance liquid chromatography (HPLC) experiment, most often done in the undergraduate analytical instrumentation laboratory course, generally illustrates reversed-phase chromatography using a commercial C[subscript]18 silica column. To avoid the expense of periodic column replacement and introduce a choice of columns with different…

  15. Analytical methods for determination of alkaloids and saponins from roots of Caulophyllum thalictroids (L) Michx using UPLC HPLC and HPTLC

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A comparison study of analytical methods including HPLC, UPLC and HPTLC are presented in this paper for the determination of major alkaloid and triterpene saponins from the roots of Caulophyllum thalictroides (L.) Michx. (blue cohosh) and dietary supplements claiming to contain blue cohosh. The meth...

  16. Quantitative analysis of liquid formulations using FT-Raman spectroscopy and HPLC The case of diphenhydramine hydrochloride in Benadryl.

    PubMed

    Orkoula, M G; Kontoyannis, C G; Markopoulou, C K; Koundourellis, J E

    2006-06-16

    The capability of FT-Raman spectroscopy for the fast and non-destructive quantitative analysis of liquid formulations was tested and the results were compared to those obtained by HPLC. Diphenhydramine hydrochloride (DPH), the active ingredient of Benadryl, was determined in the presence of the numerous excipients of the elixir. A Raman calibration model was developed by measuring the peak intensities of different standard solutions of DPH vibration at 1003 cm(-1). Application of the calibration model on the peak intensity recorded from the as-received commercially available sample with 2.5 mg ml(-1) DPH nominal value yielded a value of 2.49+/-0.05 mg ml(-1) DPH. The reliability of this method was verified by testing it against the conventionally used HPLC. The results from both methods were in excellent agreement. The main advantage of Raman over HPLC method during routine analysis is that is considerably faster and less solvent consuming. Furthermore, Raman spectroscopy is non-destructive for the sample. On the other hand, the detection limit for Raman spectroscopy is much higher than the corresponding for the HPLC methodology. PMID:16621405

  17. [Study on limit detection of flavones in diterpene ginkgolides meglumine injection materials by LC-MS and HPLC-DAD].

    PubMed

    Bi, Sen; Li, Yan-jing; Huang, Wen-zhe; Kang, Dan-yu; Ding, Gang; Xiao, Wei

    2015-08-01

    Limit test of flavones in diterpene ginkgolides meglumine injection materials by UV-Vis and HPLC-DAD method was studied in this essay. The HPLC-DAD method has lower LOD (about 1% of the UV-Vis), that is, the sensitivity is higher than UV-Vis method. Through the analysis of the kinds of flavonoids ingredients in the samples by LC-MS, the three compounds with highest contents are kaempferol, quercetin and isorhamnetin. Kaempferol, quercetin and isorhamnetin were chosen as reference compounds for HPLC analysis, and the HPLC separation analysis was carried on an Agilent Eclipse plus C18 column (4.6 mm x 250 mm, 5 μm) with methanol and water containing 0.4% phosphoric acid (50: 50) as mobile phase, and the flow rate was 1.0 mL x min(-1). The detection wavelength was set at 360 nm. This method has good specificity, precision and reproducibility. The LODs of quercetin, kaempferide and isorhamnetin were 27.6, 22.3, 29.5 μg x L(-1). The average recovery was 87.9% (RSD 3.3%), 91.7% (RSD 3.1%), 88.3 (RSD 1.3%) for quercetin, kaempferide and isorhamnetin, respectively. Based on the 10 batches of sample results and sensitivity of different HPLC, the content of total flavonoids ingredients of diterpene ginkgolides meglumine injection materials was limited no more than 2 x 10(-5). This method is simple, quick and has good maneuverability, and could be used to the limit test of flavonoids in the diterpene ginkgolides meglumine injection materials. PMID:26790294

  18. Analysis of natural red dyes (cochineal) in textiles of historical importance using HPLC and multivariate data analysis.

    PubMed

    Serrano, Ana; Sousa, Micaela M; Hallett, Jessica; Lopes, João A; Oliveira, M Conceição

    2011-08-01

    A new analytical approach based on high-performance liquid chromatography with diode array detector (HPLC-DAD) and multivariate data analysis was applied and assessed for analyzing the red dye extracted from cochineal insects, used in precious historical textiles. The most widely used method of analysis involves quantification of specific minor compounds (markers), using HPLC-DAD. However, variation in the cochineal markers concentration, use of aggressive dye extraction methods and poor resolution of HPLC chromatograms can compromise the identification of the precise insect species used in the textiles. In this study, a soft extraction method combined with a new dye recovery treatment was developed, capable of yielding HPLC chromatograms with good resolution, for the first time, for historical cochineal-dyed textiles. After principal components analysis (PCA) and mass spectrometry (MS), it was possible to identify the cochineal species used in these textiles, in contrast to the accepted method of analysis. In order to compare both methodologies, 7 cochineal species and 63 historical cochineal insect specimens were analyzed using the two approaches, and then compared with the results for 15 historical textiles in order to assess their applicability to real complex samples. The methodology developed here was shown to provide more accurate and consistent information than the traditional method. Almost all of the historical textiles were dyed with Porphyrophora sp. insects. These results emphasize the importance of adopting the proposed methodology for future research on cochineal (and related red dyes). Mild extraction methods and HPLC-DAD/MS(n) analysis yield distinctive profiles, which, in combination with a PCA reference database, are a powerful tool for identifying red insect dyes. PMID:21626194

  19. 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.

  20. Combination of automatic HPLC-RIA method for determination of estrone and estradiol in serum.

    PubMed

    Yasui, T; Yamada, M; Kinoshita, H; Uemura, H; Yoneda, N; Irahara, M; Aono, T; Sunahara, S; Mito, Y; Kurimoto, F; Hata, K

    1999-01-01

    We developed a highly sensitive assay for estrone and 17 beta-estradiol in serum. Estrone and 17 beta-estradiol, obtained by solid-phase extraction using a Sep pak tC18 cartridge, were purified by high-performance liquid chromatography (HPLC). Quantitation of estrone and 17 beta-estradiol were carried out by radioimmunoassay. Not insignificantly, this automatic system of extraction and HPLC succeeded in analyzing 80 samples a week. Intra-assay coefficients of variation (CV) for estrone and 17 beta-estradiol ranged from 19.5 to 28.7%, and from 8.5 to 13.7%, respectively. The minimum detectable dose for estrone and 17 beta-estradiol were 1.04 pg/ml and 0.64 pg/ml, respectively. The serum levels of 17 beta-estradiol using our method strongly correlated with those by Gas chromatography mass spectrometry (GC-MS). The serum levels of estrone and 17 beta-estradiol in 154 peri- and postmenopausal women were estimated to be between 15 and 27 pg/ml and between 3.5 and 24.0 pg/ml, respectively, while the serum level of 17 beta-estradiol in postmenopausal women, in particular, was estimated to be from 3.5 to 6.3 pg/ml. For postmenopausal women who suffered from vasomotor symptoms, the mean levels of estrone and 17 beta-estradiol at 12 to 18 hours after treatment with daily 0.625 mg conjugated equine estrogen (CEE) and 2.5 mg medroxyprogesterone acetate (MPA) were 135.0 and 21.3 pg/ml at 12 months, respectively. On the other hand, levels of estrone and 17 beta-estradiol at 12 to 18 hours after treatment with CEE and MPA every other day, were 73.4 and 15.3 pg/ml, respectively. These highly sensitive assays for estrone and 17 beta-estradiol are useful in measuring low levels of estrogen in postmenopausal women, and monitoring estrogen levels in women receiving CEE as hormone replacement therapy. PMID:10633293

  1. Determination of ephedrine alkaloids in botanicals and dietary supplements by HPLC-UV: collaborative study.

    PubMed

    Roman, Mark C

    2004-01-01

    An international collaborative study was conducted of a high-performance liquid chromatography (HPLC)-UV method for the determination of the major (ephedrine [EP] and pseudoephedrine [PS]) and minor (norephedrine [NE], norpseudoephedrine [NP], methylephedrine [ME], and methylpseudoephedrine [MP]) alkaloids in selected dietary supplements representative of the commercially available products. Ten collaborating laboratories determined the ephedrine-type alkaloid content in 8 blind replicate samples. Five products contained ephedra ground herb or ephedra extract. These 5 products included ground botanical raw material of Ephedra sinica, a common powdered extract of Ephedra sinica, a finished product containing only Ephedra sinica ground botanical raw material, a complex multicomponent dietary supplement containing Ma Huang, and a high-protein chocolate flavored drink mix containing Ma Huang extract. In addition, collaborating laboratories received a negative control and negative control spiked with ephedrine alkaloids at high and low levels for recovery studies. Test extracts were treated to solid-phase extraction using a strong-cation exchange column to help remove interferences. The HPLC analyses were performed on a polar-embedded phenyl column using UV detection at 210 nm. Repeatability relative standard deviations (RSDr) ranged from 0.64-3.0% for EP and 2.0-6.6% for PS, excluding the high protein drink mix. Reproducibility relative standard deviations (RSDR) ranged from 2.1-6.6% for EP and 9.0-11.4% for PS, excluding the high protein drink mix. Recoveries ranged from 84.7-87.2% for EP and 84.6-98.2% for PS. The data developed for the minor alkaloids are more variable with generally unsatisfactory HORRATS (i.e., >2). However, since these alkaloids generally add little to the total alkaloid content of the products, the method gives satisfactory results in measuring total alkaloid content (RSDr 0.85-3.13%; RSDR 2.03-10.97%, HORRAT 0.69-3.23, exclusive of the results

  2. HPLC-DAD phenolic profile, cytotoxic and anti-kinetoplastidae activity of Melissa officinalis.

    PubMed

    Cunha, Francisco; Tintino, Saulo R; Figueredo, Fernando; Barros, Luiz; Duarte, Antonia E; Vega Gomez, Maria Celeste; Coronel, Cathia Cecilia; Rolón, Mírian; Leite, Nadghia; Sobral-Souza, Celestina E; Brito, S V; Waczuc, Emily Pansera; Boligon, Aline Augusti; Athayde, Margareth; Kamdem, Jean Paul; Coutinho, Henrique Douglas Melo; Franco, Jéferson

    2016-09-01

    Context Melissa officinalis subsp. inodora Bornm. (Lamiaceae) has been used since ancient times in folk medicine against various diseases, but it has not been investigated against protozoa. Objective To evaluate the activities of M. officinalis against Leishmania braziliensis, Leishmania infantum and Trypanosoma cruzi as well as its cytotoxicity in fibroblast cell line. Materials and methods The fresh leaves were chopped into 1 cm(2) pieces, washed and macerated with 99.9% of ethanol for 72 h at room temperature. Antiparasitic activity of M. officinalis was accessed by direct counting of cells after serial dilution, while the cytotoxicity of M. officinalis was evaluated in fibroblast cell line (NCTC929) by measuring the reduction of resazurin. The test duration was 24 h. High-performance liquid chromatography (HPLC) was used to characterise the extract. Results The extract at concentrations of 250 and 125 μg/mL inhibited 80.39 and 54.27% of promastigote (LC50  value = 105.78 μg/mL) form of L. infantum, 80.59 and 68.61% of L. brasiliensis (LC50 value  = 110.69 μg/mL) and against epimastigote (LC50 value  = 245.23 μg/mL) forms of T. cruzi with an inhibition of 54.45 and 22.26%, respectively, was observed. The maximum toxicity was noted at 500 μg/mL with 95.41% (LC50  value = 141.01 μg/mL). The HPLC analysis identified caffeic acid and rutin as the major compounds. Discussion The inhibition of the parasites is considered clinically relevant (< 500 μg/mL). Rutin and caffeic acids may be responsible for the antiprotozoal effect of the extract. Conclusion The ethanol extract of M. officinalis can be considered a potential alternative source of natural products with antileishmania and antitrypanosoma activities. PMID:26864563

  3. Improved quantification of pyrogenic carbon in soils and sediments by a HPLC-DAD method

    NASA Astrophysics Data System (ADS)

    Wiedemeier, D. B.; Hilf, M. D.; Smittenberg, R. H.; Schmidt, M. W. I.

    2012-04-01

    Fire-derived (pyrogenic) carbon (PyC) is produced by the incomplete combustion of biomass, for example during wildfires. It can persist in the environment for a long time due to its relative resistance against biological and chemical breakdown. Its accurate quantification in soils and sediments is of great interest because the slow turn-over of PyC has implications for the global carbon cycle and carbon budget calculations. Moreover, PyC in pedological and sedimentological records can be used to reconstruct wildfire history or to investigate historical periods like the industrialization. A whole suite of PyC quantification methods exists because PyC is not a defined chemical structure but rather a continuum of thermally altered biomass. The benzene polycarboxylic acids (BPCA) analysis is a molecular marker method that was shown to give conservative estimates of PyC quantity in soils. In addition, it yields qualitative information about the degree of aromaticity and condensation of PyC. The commonly used BPCA method consists in digesting samples with nitric acid that breaks down the PyC into a suite of BPCAs, which are cleaned, derivatized and finally analyzed by gas chromatography-flame ionization detection (GC-FID). Here, we present a modified BPCA method for soils and sediments that uses a high performance liquid chromatography system coupled to diode array detection (HPLC-DAD). We demonstrate that this method greatly enhances the reproducibility of PyC quantification in soil and sediment samples while significantly reducing analysis time. Moreover, much less sample material is needed for precise PyC quantification and we show that the HPLC-DAD method yields consistently higher PyC contents than the GC-FID method. Additionally, the modified method also facilitates δ13C and 14C measurements of the PyC fraction in these complex matrix samples. The isotopic information further improves the assessment of PyC budgets in the environment and the reconstruction of past

  4. Collaborative study for the validation of an improved HPLC assay for recombinant IFN-alfa-2.

    PubMed

    Jönsson, K H; Daas, A; Buchheit, K H; Terao, E

    2016-01-01

    The current European Pharmacopoeia (Ph. Eur.) texts for Interferon (IFN)-alfa-2 include a nonspecific photometric protein assay using albumin as calibrator and a highly variable cell-based assay for the potency determination of the protective effects. A request was expressed by the Official Medicines Control Laboratories (OMCLs) for improved methods for the batch control of recombinant interferon alfa-2 bulk and market surveillance testing of finished products, including those formulated with Human Serum Albumin (HSA). A HPLC method was developed at the Medical Products Agency (MPA, Sweden) for the testing of IFN-alfa-2 products. An initial collaborative study run under the Biological Standardisation Programme (BSP; study code BSP039) revealed the need for minor changes to improve linearity of the calibration curves, assay reproducibility and robustness. The goal of the collaborative study, coded BSP071, was to transfer and further validate this improved HPLC method. Ten laboratories participated in the study. Four marketed IFN-alfa-2 preparations (one containing HSA) together with the Ph. Eur. Chemical Reference Substance (CRS) for IFN-alfa-2a and IFN-alfa-2b, and in-house reference standards from two manufacturers were used for the quantitative assay. The modified method was successfully transferred to all laboratories despite local variation in equipment. The resolution between the main and the oxidised forms of IFN-alfa-2 was improved compared to the results from the BSP039 study. The improved method even allowed partial resolution of an extra peak after the principal peak. Symmetry of the main IFN peak was acceptable for all samples in all laboratories. Calibration curves established with the Ph. Eur. IFN-alfa-2a and IFN-alfa-2b CRSs showed excellent linearity with intercepts close to the origin and coefficients of determination greater than 0.9995. Assay repeatability, intermediate precision and reproducibility varied with the tested sample within acceptable

  5. A simple analytical procedure to replace HPLC for monitoring treatment concentrations of chloramine-T on fish culture facilities

    USGS Publications Warehouse

    Dawson, Verdel K.; Meinertz, Jeffery R.; Schmidt, Larry J.; Gingerich, William H.

    2003-01-01

    Concentrations of chloramine-T must be monitored during experimental treatments of fish when studying the effectiveness of the drug for controlling bacterial gill disease. A surrogate analytical method for analysis of chloramine-T to replace the existing high-performance liquid chromatography (HPLC) method is described. A surrogate method was needed because the existing HPLC method is expensive, requires a specialist to use, and is not generally available at fish hatcheries. Criteria for selection of a replacement method included ease of use, analysis time, cost, safety, sensitivity, accuracy, and precision. The most promising approach was to use the determination of chlorine concentrations as an indicator of chloramine-T. Of the currently available methods for analysis of chlorine, the DPD (N,N-diethyl-p-phenylenediamine) colorimetric method best fit the established criteria. The surrogate method was evaluated under a variety of water quality conditions. Regression analysis of all DPD colorimetric analyses with the HPLC values produced a linear model (Y=0.9602 X+0.1259) with an r2 value of 0.9960. The average accuracy (percent recovery) of the DPD method relative to the HPLC method for the combined set of water quality data was 101.5%. The surrogate method was also evaluated with chloramine-T solutions that contained various concentrations of fish feed or selected densities of rainbow trout. When samples were analyzed within 2 h, the results of the surrogate method were consistent with those of the HPLC method. When samples with high concentrations of organic material were allowed to age more than 2 h before being analyzed, the DPD method seemed to be susceptible to interference, possibly from the development of other chloramine compounds. However, even after aging samples 6 h, the accuracy of the surrogate DPD method relative to the HPLC method was within the range of 80–120%. Based on the data comparing the two methods, the U.S. Food and Drug Administration

  6. A simple analytical procedure to replace HPLC for monitoring treatment concentrations of chloramine-T on fish culture facilities

    USGS Publications Warehouse

    Dawson, V.K.; Meinertz, J.R.; Schmidt, L.J.; Gingerich, W.H.

    2003-01-01

    Concentrations of chloramine-T must be monitored during experimental treatments of fish when studying the effectiveness of the drug for controlling bacterial gill disease. A surrogate analytical method for analysis of chloramine-T to replace the existing high-performance liquid chromatography (HPLC) method is described. A surrogate method was needed because the existing HPLC method is expensive, requires a specialist to use, and is not generally available at fish hatcheries. Criteria for selection of a replacement method included ease of use, analysis time, cost, safety, sensitivity, accuracy, and precision. The most promising approach was to use the determination of chlorine concentrations as an indicator of chloramine-T. Of the currently available methods for analysis of chlorine, the DPD (N,N-diethyl-p-phenylenediamine) colorimetric method best fit the established criteria. The surrogate method was evaluated under a variety of water quality conditions. Regression analysis of all DPD colorimetric analyses with the HPLC values produced a linear model (Y=0.9602 X+0.1259) with an r2 value of 0.9960. The average accuracy (percent recovery) of the DPD method relative to the HPLC method for the combined set of water quality data was 101.5%. The surrogate method was also evaluated with chloramine-T solutions that contained various concentrations of fish feed or selected densities of rainbow trout. When samples were analyzed within 2 h, the results of the surrogate method were consistent with those of the HPLC method. When samples with high concentrations of organic material were allowed to age more than 2 h before being analyzed, the DPD method seemed to be susceptible to interference, possibly from the development of other chloramine compounds. However, even after aging samples 6 h, the accuracy of the surrogate DPD method relative to the HPLC method was within the range of 80-120%. Based on the data comparing the two methods, the U.S. Food and Drug Administration has

  7. Determination of 5-bromo-2'-deoxyuridine (BRDU) in well water by high performance liquid chromatography (HPLC). Technical report, February-September 1992

    SciTech Connect

    Dennis, W.E.; Rosencrance, A.B.

    1992-09-01

    A liquid chromatographic method has been developed for the analysis of 5-Br deoxyuridine (BrdU) in well water. The samples are injected directly onto a high performance liquid chromatograph (HPLC) without further sample preparation. Separation of BrdU from possible interferences found in well water was achieved by using a C-18 column and a mobile phase containing water and methanol. A programmable ultraviolet (UV) detector was used to monitor the effluent for BrdU. HPLC provides a rapid and reproducible method for the analysis of BrdU. High Performance Liquid Chromatograph (HPLC), 5-Bromo-2'deoxyuridine (BrdU), Ultraviolet (UV).

  8. [Assessment of serum estrogen levels by RIA with HPLC during hormone replacement therapy].

    PubMed

    Yasui, T; Uemura, H; Yoneda, N; Irahara, M; Aono, T; Sunahara, S; Hata, K

    1995-07-01

    We studied the serum estradiol and estrone levels in 146 peri and postmenopausal women, and in 38 women who had complained of various climacteric disturbance symptoms during daily hormone replacement therapy (HRT) with conjugated equine estrogen (CEE) 0.625 mg and medroxyprogesterone acetate (MPA) 2.5 mg. Serum estradiol and estrone were measured before treatment, and at 6 months, and after one year of the HRT therapy by HPLC-radioimmunoassay. In 146 peri and postmenopausal women, the serum level of estradiol was from 3 to 6pg/ml. The serum level of estradiol in 38 women after HRT significantly increased (p < 0.01) from 3.34 to 23.6 pg/ml at 6 months, and 21.5 pg/ml at 12 months. The serum level of estrone significantly increased (p < 0.01) from 26.6pg/ml to 156.7pg/ml at 6 months, and 137.2pg/ml at 12 month. These results are very useful for deciding on the doses of hormones and the expected serum estradiol level in HRT for Japanese women. PMID:7636337

  9. [Application and improvement of aflatoxin analysis in foods using a multifunctional column and HPLC].

    PubMed

    Goda, Y; Akiyama, H; Otsuki, T; Fujii, A; Toyoda, M

    2001-02-01

    In an earlier report, we developed a rapid, sensitive and clean method consisting of non-chloroform extraction, clean-up on a commercial multifunctional cartridge column and HPLC with fluorescence detection for the analyses of aflatoxins. In this report, we applied this method to analyze aflatoxins in nuts, giant corn, cereals, spice and black teas. The method was effective for macadamia nuts, walnuts, hazelnuts, brazil nuts, giant corn, rice, wheat and buckwheat, and the recoveries of aflatoxins B1, B2, G1 and G2 spiked in them at the level of 10 ng/g were 85-106%. However, in the chromatograms of spices and black tea, many background peaks were observed. Therefore, we added a purification step with an affinity column to the clean-up of these samples with the multifunctional cartridge column. After the additional purification, most of the background peaks were gone. The recoveries of aflatoxins B1, B2 and G1 spiked at the level of 10 ng/g were 71-112% except for the case of B2 in white pepper (48%). The recoveries of G2 were 49-95%. PMID:11383158

  10. Determination of Saponin Content in Hang Maidong and Chuan Maidong via HPLC-ELSD Analysis.

    PubMed

    Li, Xian-En; Wang, Yu-Xia; Sun, Peng; Liao, Deng-Qun

    2016-01-01

    Zhejiang and Sichuan are regarded as two genuine producing areas of Ophiopogonis radix in China. To study the difference in the quality of Ophiopogonis radix from these two places, the contents of three reported bioactive saponins, that is, ophiopogonins B, D, and D', in tubers and fibrous roots of Ophiopogon japonicus from Cixi city of Zhejiang and Santai county of Sichuan were quantified using HPLC-ELSD method and compared. Ophiopogonin B and ophiopogonin D' content in tubers of HMD were higher than those in radix of CMD, whereas ophiopogonin D in HMD was about twice lower than that of CMD. Three ophiopogonins were all detected in fibrous roots of both HMD and CMD. Their averaged content in fibrous roots of CMD was about twice higher than that in tubers of CMD. Ophiopogonin D in fibrous roots of CMD was about five times higher than that of HMD. Our biochemical assay revealed that fibrous roots and tubers of CMD can be of an important saponin source, especially for ophiopogonin D. PMID:26925295

  11. Quantification of Hydrazine in Human Urine by HPLC-MS-MS.

    PubMed

    Isenberg, Samantha L; Carter, Melissa D; Crow, Brian S; Graham, Leigh Ann; Johnson, Darryl; Beninato, Nick; Steele, Kandace; Thomas, Jerry D; Johnson, Rudolph C

    2016-05-01

    Currently used on F-16 fighter jets and some space shuttles, hydrazine could be released at toxic levels to humans as a result of an accidental leakage or spill. Lower-level exposures occur in industrial workers or as a result of the use of some pharmaceuticals. A method was developed for the quantitation of hydrazine in human urine and can be extended by dilution with water to cover at least six orders of magnitude, allowing measurement at all clinically significant levels of potential exposure. Urine samples were processed by isotope dilution, filtered, derivatized and then quantified by HPLC-MS-MS. The analytical response ratio was linearly proportional to the urine concentration of hydrazine from 0.0493 to 12.3 ng/mL, with an average correlation coefficientRof 0.9985. Inter-run accuracy for 21 runs, expressed as percent relative error (% RE), was ≤14%, and the corresponding precision, expressed as percent relative standard deviation (% RSD), was ≤15%. Because this method can provide a quantitative measurement of clinical samples over six orders of magnitude, it can be used to monitor trace amounts of hydrazine exposure as well as industrial and environmental exposure levels. PMID:26977107

  12. HPLC-ELSD determination of kanamycin B in the presence of kanamycin A in fermentation broth.

    PubMed

    Zhang, Yong; He, Hui-Min; Zhang, Jin; Liu, Feng-Jiao; Li, Chao; Wang, Bing-Wu; Qiao, Ren-Zhong

    2015-03-01

    A novel method for the direct determination of kanamycin B in the presence of kanamycin A in fermentation broth using high performance liquid chromatography with evaporative light scattering detector (HPLC-ELSD) was developed. An Agilent Technologies C18 column was utilized, evaporation temperature of 40°C and nitrogen pressure of 3.5 bar, the optimized mobile phase was water-acetonitrile (65:35, v/v), containing 11.6 mm heptafluorobutyric acid (isocratic elution with flow rate of 0.5 mL/min) with the gain 11. Kanamycin B was eluted at 5.6 min with an asymmetry factor of 1.827. The method showed good linearity over the concentration range of 0.05 to 0.80 mg/mL for the kanamycin B (r(2) = 0.9987). The intra-day and inter-day coefficients of variation obtained from kanamycin B were less than 4.3%. Mean recovery of kanamycin B from spiked fermentation broth was 95%. The developed method was applied to the determination of kanamycin B without any interference from other constituents in the fermentation broth. This method offers simple, rapid and quantitative detection of kanamycin B. PMID:25042110

  13. The RP-HPLC method for simultaneous estimation of esomeprazole and naproxen in binary combination

    PubMed Central

    Jain, Deepak Kumar; Jain, Nitesh; Charde, Rita; Jain, Nilesh

    2011-01-01

    Objective: A simple, precise, reliable, rapid, sensitive and validated RP-HPLC method has been developed to determine esomeprazole magnesium trihydrate (ESO) and naproxen (NAP) in synthetic mixture form. Materials and Methods: Chromatographic separation achieved isocratically on Phenomenex, Luna C18 column (5 μm, 150mm × 4.60mm) and acetonitrile: phosphate buffer (pH 7.0) in the ratio of 50:50 (v/v) as the mobile phase, at a flow rate of 0.5 ml/min. Detection was carried out at 300 nm. The retention times for NAP and ESO was found to be 2.67 ±0.014 and 5.65 ±0.09 min respectively. Parameters such as linearity, precision, accuracy, recovery, specificity and ruggedness are studied as reported in the ICH guidelines. Results: The method was linear in the concentration range of 50-250 μg/ml for NAP and 2-10 μg/ml for ESO with correlation coefficient of 0.999 and 0.998 respectively. The mean recoveries obtained for NAP and ESO were 100.01% and 97.76 % respectively and RSD was less than 2. The correlation coefficients for all components are close to 1. Conclusions: Developed method was found to be accurate, precise, selective and rapid for simultaneous estimation of NAP and ESO. PMID:23781450

  14. A rapid HPLC method for simultaneous determination of tretinoin and isotretinoin in dermatological formulations.

    PubMed

    Tashtoush, Bassam M; Jacobson, Elaine L; Jacobson, Myron K

    2007-02-19

    A rapid method using an isocratic high-pressure liquid chromatography and UV detection for determination of both all-trans retinoic acid (tretinoin) and 13-cis retinoic acid (isotretinoin) in dermatological preparations is presented. Tretinoin and isotretinoin samples were extracted with acetonitrile by a procedure that can be completed in less than 10 min. Subsequent separation and quantification of amounts as low as 10 pmol was accomplished in less than 15 min using reversed-phase HPLC with isocratic elution with 0.01% trifluoroacetic acid (TFA)/acetonitrile (15:85, v/v). Validation experiments confirmed the precision and accuracy of the method. When applied to commercial tretinoin samples, recoveries of 104.9% for cream formulations and 107.7% for gel formulations were obtained. Application of the method for analysis of a tretinoin cream exposed to solar simulated light (SSL) demonstrated detection of the major photoisomerization product isotretinoin as well as 9-cis retinoic acid, demonstrating the utility of the method for studies of tretinoin photostability. The method should also facilitate studies of the formulation compatibility and photocompatibility of tretinoin with agents that may improve its clinical tolerability. PMID:17045442

  15. [Application of HPLC-UV method for aripiprazole determination in serum].

    PubMed

    Synowiec, Anna; Gomółka, Ewa; Zyss, Tomasz; Zieba, Andrzej; Florek, Ewa; Piekoszewski, Wojciech

    2012-01-01

    Aripiprazole is a new drug applied in schizophrenia treatment. There are not strict indications for aripiprazole therapeutic drug monitoring. Despite, serum aripiprazole measuring would help control the drug doses effectiveness. The drug monitoring can eliminate overdosing, adverse effects and let control proper drug ingestion. The aim of the paper was to develop a simple method for aripiprazole determination in serum for therapeutic drug monitoring. High performance liquid chromatography with spectrophotometric detection (HPLC-UV) was used. Resolution was performed on LC-8 column; moving phase was solution 0,025M trimethylammonium buffer: acetonitrile (62:38). Isocratic flow was 1,2 ml/min; internal standard (IS) was promazine; monitored wavelength was lambda=214 nm. The validation parameters were: limits of linearity (LOL) 100-800 ng/ml, limit of detection (LOD) 10 ng/ml, limit of quantity (LOQ) 100 ng/ml. Coefficient of variation (CV) describing accuracy and precision didn't cross 10%. The method was useful for therapeutic drug monitoring in serum of patients treated with aripiprazole. PMID:23421079

  16. Enzyme-assisted extraction for the HPLC determination of aflatoxin M1 in cheese.

    PubMed

    Pietri, Amedeo; Fortunati, Paola; Mulazzi, Annalisa; Bertuzzi, Terenzio

    2016-02-01

    The extraction of aflatoxin M1 (AFM1) from cheese is generally carried out using chlorinated organic solvents. In this study, two innovative methods were developed, based on an enzyme-assisted (EA) extraction using proteolytic enzymes (pepsin or pepsin-pancreatin). After purification through an immunoaffinity column, AFM1 is determined by HPLC-FLD. A comparison between the new EA methods and an established chloroform (CH) method was carried out on 24 cheese samples. The results showed that the extraction efficiency of the EA methods was independent of ripening time of cheese, whereas the CH method was not able to fully recover AFM1 from ripened cheeses. The simpler (pepsin) of the two methods has been adopted by our laboratory for routine analysis of AFM1 in cheese. In comparison with the CH method, the pepsin-HCl (P-HCl) method is simpler, avoiding solvent evaporation, dissolution and partition in a separating funnel; moreover, it gives higher recoveries, comparable LOD and LOQ and more accurate results. PMID:26304342

  17. Enantioselective determination of triazole fungicide epoxiconazole bioaccumulation in tubifex based on HPLC-MS/MS.

    PubMed

    Liu, Chunxiao; Wang, Bo; Xu, Peng; Liu, Tiantian; Di, Shanshan; Diao, Jinling

    2014-01-15

    In this study, the enantioselective bioaccumulation of epoxiconazole enantiomers in tubifex (Oligochaeta, Tubificida) was investigated in two uptake pathways. A sensitive and rapid chiral method was developed for the determination of epoxiconazole enantiomers in tubifex and soil based on high-performance liquid chromatography coupled with triple-quadrupole mass spectrometry (HPLC-MS/MS). In the spiked-water or spiked-soil treatments, enantioselective bioaccumulation of epoxiconazole in tubifex was obersved. For spiked-water treatment, (-)-epoxiconazole accumulated in tubifex to a greater extent than (+)-epoxiconazole, leading to enrichments with a composition (-) > (+). However, for spiked-soil treatment, the enantioselectivity in tubifex was reversed with a preferential accumulation of (+)-epoxiconazole. Calculated accumulation factors (AFs) indicated that epoxiconazole in spiked-water treatment had higher bioaccumulation potential than that in spiked-soil treatment. The results from the spiked-soil treatment also revealed that the dissipation of epoxiconazole in soil was enantioselective, and tubifex has positive effects on epoxiconazole diffusion from soil to overlying water. PMID:24364671

  18. Stability-Indicating HPLC Determination of Trandolapril in Bulk Drug and Pharmaceutical Dosage Forms

    PubMed Central

    Al-Hawash, Leena A.; Shakya, Ashok K.; Saleem, Maher L.

    2015-01-01

    A rapid, simple, accurate, precise, economical, robust, and stability indicating reverse phase HPLC-PDA procedure has been developed and validated for the determination of trandolapril. The trandolapril was separated isocratically on Hypersil-Gold C18 column (250 mm × 4.6 mm, 5 μm) with a mobile phase consisting of 50% acetonitrile and 50% water (containing 0.025% triethylamine, pH 3.0 ± 0.1), at 25 ± 2°C. Retention time of the drug was ~4.6 min. The eluted compounds were monitored and identified at 210 nm. The linearity of the method was excellent (r2 > 0.9999) over the concentration range of 1–24 μg/mL; the limit of detection (LOD) and limit of quantitation (LOQ) were 0.0566 μg/mL and 0.1715 μg/mL, respectively. The overall precision was less than 2%. Mean recovery of trandolapril was more than 99%; no interference was found from the component present in the preparation. Stability studies indicate that the drug was stable to sunlight and UV light. The drug gives 6 different oxidative products on exposure to hydrogen peroxide. Slight degradation was observed in acidic condition. Degradation was higher in the alkaline condition compared to other conditions. The robustness of the method was studied using factorial design experiment. PMID:25802524

  19. Stability indicating HPLC-UV method for determination of dapoxetine HCl in pharmaceutical product.

    PubMed

    Liew, Kai Bin; Peh, Kok Khiang

    2014-01-01

    A stability-indicating HPLC-UV method for the determination of dapoxetine hydrochloride in solution and pharmaceutical product was developed. The mobile phase was composed of acetonitrile and 0.2 M ammonium acetate buffer at 50 : 50 ratio. The chromatographic parameters, theoretical plates (N), tailing factor (T), capacity factor (k') and peak asymmetry factor (As) were calculated. Stress degradation studies, namely, acid, alkali, oxidation, heat and UV light, were performed. The analyte was eluted at 5.8 min using gradient system at a flow rate of 1.5 mL/min. The theoretical plates count was > 2000, tailing factor < 1.54, capacity factor > 5.38 and peak asymmetry factor was < 1.10. The method was linear from 1 to 40 microg/mL with a correlation coefficient of 0.9994. The intraday precision and accuracy values were 0.14-1.54% and 0.63-1.83%, respectively. On the other hand, the interday precision and accuracy results were 0.49-1.83% and 1.15-1.85%, respectively. The drug solution was stable at ambient room temperature (26 degrees C) for 48 h. Dapoxetine HCI was found susceptible to oxidation and degraded slightly under acid and alkali conditions but was stable under UV light and heat. No interference from tablet excipiets and degradation products was found. Hence, the method can be employed as a stability-indicating method for the determination of dapoxetine HCl in pharmaceutical products. PMID:25265818

  20. HPLC and ELISA analyses of larval bile acids from Pacific and western brook lampreys

    USGS Publications Warehouse

    Yun, S.-S.; Scott, A.P.; Bayer, J.M.; Seelye, J.G.; Close, D.A.; Li, W.

    2003-01-01

    Comparative studies were performed on two native lamprey species, Pacific lamprey (Lampetra tridentata) and western brook lamprey (Lampetra richardsoni) from the Pacific coast along with sea lamprey (Petromyzon marinus) from the Great Lakes, to investigate their bile acid production and release. HPLC and ELISA analyses of the gall bladders and liver extract revealed that the major bile acid compound from Pacific and western brook larval lampreys was petromyzonol sulfate (PZS), previously identified as a migratory pheromone in larval sea lamprey. An ELISA for PZS has been developed in a working range of 20pg-10ng per well. The tissue concentrations of PZS in gall bladder were 127.40, 145.86, and 276.96??g/g body mass in sea lamprey, Pacific lamprey, and western brook lamprey, respectively. Releasing rates for PZS in the three species were measured using ELISA to find that western brook and sea lamprey released PZS 20 times higher than Pacific lamprey did. Further studies are required to determine whether PZS is a chemical cue in Pacific and western brook lampreys. ?? 2003 Elsevier Inc. All rights reserved.

  1. Plasma mitomycin C concentrations determined by HPLC coupled to solid-phase extraction.

    PubMed

    Paroni, R; Arcelloni, C; De Vecchi, E; Fermo, I; Mauri, D; Colombo, R

    1997-04-01

    The aim of this study was to set up a method for quantification of plasma mitomycin C (MMC) concentrations during intravesical chemotherapy delivered in the presence of local bladder hyperthermia (HT). In comparison with existing methods, this assay, characterized by relative simplicity and efficiency, resulted in the facilitation of performance with nondedicated instrumentation or nonspecialized staff. Purification from plasma matrix was carried out by solid-phase extraction under vaccuum. The purified drug was then collected directly into the vials of the HPLC autosampler. Chromatographic analysis was performed on a reversed-phase C18 column with water:acetonitrile (85:15 by vol) as the mobile phase and the UV detector set at 365 nm. The use of porfiromycin as internal standard provided a method with good within-day precision (CV 6.0% at 5 micrograms/L, n = 6), linearity (0.5-50 micrograms/L), and specificity. The lower limit of detection (< or = 0.5 microgram/L) proved to be suitable for plasma pharmacokinetics monitoring in two tested patients treated with MMC + HT for superficial bladder cancer. PMID:9105262

  2. Simultaneous HPLC determination of 22 components of essential oils; method robustness with experimental design.

    PubMed

    Porel, A; Sanyal, Y; Kundu, A

    2014-01-01

    The aim of the present study was the development and validation of a simple, precise and specific reversed phase HPLC method for the simultaneous determination of 22 components present in different essential oils namely cinnamon bark oil, caraway oil and cardamom fruit oil. The chromatographic separation of all the components was achieved on Wakosil-II C18 column with mixture of 30 mM ammonium acetate buffer (pH 4.7), methanol and acetonitrile in different ratio as mobile phase in a ternary linear gradient mode. The calibration graphs plotted with five different concentrations of each component were linear with a regression coefficient R(2) >0.999. The limit of detection and limit of quantitation were estimated for all the components. Effect on analytical responses by small and deliberate variation of critical factors was examined by robustness testing with Design of Experiment employing Central Composite Design and established that this method was robust. The method was then validated for linearity, precision, accuracy, specificity and demonstrated to be applicable to the determination of the ingredients in commercial sample of essential oil. PMID:24799735

  3. Rapid Analysis of Glibenclamide Using an Environmentally Benign Stability-Indicating RP-HPLC Method

    PubMed Central

    Haq, Nazrul; Alanazi, Fars Kaed; Alsarra, Ibrahim Abdullah; Shakeel, Faiyaz

    2014-01-01

    An environmentally benign RP-HPLC approach for rapid analysis of glibenclamide in pure form, developed nanoemulsion and commercial tablets was developed and validated in present investigation. The green chromatographic identification was performed on Lichrosphere 250 X 4.0 mm RP C8 column having a 5 μm packing as a stationary phase using a combination of ethanol: methanol (50:50 % v/v) as a mobile phase, at a flow rate of 1.0 mL/min with UV detection at 245 nm. The proposed method was validated for linearity, selectivity, accuracy, precision, robustness, sensitivity and specificity as per international conference on harmonization (ICH) guidelines. The utility of proposed method was verified by assay of glibenclamide in developed nanoemulsion and commercial tablets. The proposed method was found to be satisfactory in terms of selectivity, precision, accuracy, robustness, sensitivity and specificity. The content of glibenclamide in developed nanoemulsion and commercial tablets was found to be 100.50 % and 99.15 % respectively. The proposed method successfully resoled glibenclamide peak in the presence of its all type of degradation products which indicated stability-indicating property of the proposed method. These results indicated that the green chromatographic method could be successfully employed for routine analysis of glibenclamide in pure drug and various commercial formulations. PMID:25276186

  4. Determination of catecholamines and related compounds in mouse urine using column-switching HPLC.

    PubMed

    Kanamori, Takahiro; Funatsu, Takashi; Tsunoda, Makoto

    2016-04-21

    We have developed an analytical method for the determination of catecholamines and related compounds in mouse urine by column-switching HPLC. Selective extraction of the catechol compounds was performed using a precolumn modified with phenylboronic acid, which has a pH dependent affinity for the catechol structures. The pretreatment buffer, which facilitated binding of the catechols to the precolumn, was optimized to ensure high analyte recoveries and good peak shapes. We found that using the same acetonitrile content in the pretreatment buffer and hydrophilic interaction liquid chromatography mobile phase was necessary to improve peak shapes. Eight catechol compounds were selectively extracted and separated using 100 mmol L(-1) ammonium formate/acetonitrile (20/80 v/v, pH 8.0) for the extraction step, and 20 mmol L(-1) ammonium formate (pH 2.5)/acetonitrile (20/80 v/v) for elution and separation. Native fluorescence of the separated catechol compounds was monitored, and the limits of detection, corresponding to a signal to noise ratio of 3, were 9-58 nmol L(-1). Five catechol compounds (dopamine, epinephrine, norepinephrine, 3,4-dihydroxyphenylglycol, and 3,4-dihydroxymandelic acid) were successfully quantified in mouse urine. Intra- and inter-day precisions were less than 10%, and performance was superior to that afforded by manual sample pretreatment. PMID:27029966

  5. [Simple determination of residual anticoccidial drugs (diclazuril and nicarbazin) in chicken tissues by HPLC].

    PubMed

    Kanda, Maki; Ushiyama, Keiko; Igusa, Kyoko; Murayama, Mitsunori; Horie, Masakazu; Hirokado, Masako; Miyazaki, Tomoyuki

    2003-04-01

    A simple and rapid determination of anticoccidial drug residues, diclazuril (DCZ) and nicarbazin (NCZ), in chicken tissues has been developed. DCZ and NCZ were extracted with acetonitrile from chicken liver, muscle, and fat. The extract was rinsed with n-hexane saturated with acetonitrile and then evaporated. The residue was dissolved in 1.4 mL of acetonitrile-methanol (1:1), then 1.0 mL of n-hexane saturated with acetonitrile-methanol (1:1) was added, and the mixture was partitioned by the addition of 0.6 mL of water. DCZ and NCZ in the aqueous layers were determined by HPLC on an Xterra RP-18 column with acetonitrile-0.5% ammonium acetate containing 0.01 mol/L tetra-n-butylammonium hydrogen sulfate (43:57) as the mobile phase. The mean recoveries (n = 5) of DCZ and NCZ spiked in chicken tissues at the maximum residue levels were 92.0-95.6% (CV 2.4-3.0%) and 87.3-89.4% (CV 1.7-2.8%), respectively. The detection limits of DCZ and NCZ were 0.01 and 0.004 microgram/g, respectively. PMID:12846158

  6. Submerged fermentation production and characterization of intracellular triterpenoids from Ganoderma lucidum using HPLC-ESI-MS*

    PubMed Central

    Cui, Mei-lin; Yang, Huan-yi; He, Guo-qing

    2015-01-01

    As the main bioactive metabolites of Ganoderma lucidum, triterpenoids have various pharmacological effects. In this paper, the nutritional requirements and culture conditions of a submerged culture of G. lucidum were optimized using the response surface methodology; maximum mycelia biomass and intracellular triterpenoid production reached 1.87 g/100 ml and 93.21 mg/100 ml, respectively, for a culture consisting of wort 4.10% (0.041 g/ml) and yeast extract 1.89% (0.0189 g/ml), pH 5.40. For the first time, we established that wort, which is cheap and abundant, can replace the more commonly used glucose as the sole source of carbohydrate. Using high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS), 10 major ganoderic acids were tentatively identified based on the predominant fragmentation pathways with the elimination of H2O and CO2, as well as cleavage of the D-ring. PMID:26642183

  7. Absorbance detector based on a deep UV light emitting diode for narrow-column HPLC.

    PubMed

    Bui, Duy Anh; Bomastyk, Benjamin; Hauser, Peter C

    2013-10-01

    A detector for miniaturized HPLC based on deep UV emitting diodes and UV photodiodes was constructed. The measurement is accomplished by the transverse passage of the radiation from the light-emitting diode (LED) through fused-silica tubing with an internal diameter of 250 μm. The optical cell allows flexible alignment of the LED, tubing, and photodiode for optimization of the light throughput and has an aperture to block stray light. A beam splitter was employed to direct part of the emitted light to a reference photodiode and the Lambert-Beer law was emulated with a log-ratio amplifier circuitry. The detector was tested with two LEDs with emission bands at 280 and 255 nm and showed noise levels as low as 0.25 and 0.22 mAU, respectively. The photometric device was employed successfully in separations using a column of 1 mm inner diameter in isocratic as well as gradient elution. Good linearities over three orders of magnitude in concentration were achieved, and the precision of the measurements was better than 1% in all cases. Detection down to the low micromolar range was possible. PMID:23893947

  8. HPLC-DAD-ESI/MS(n) profiling of phenolic compounds from Lathyrus cicera L. seeds.

    PubMed

    Ferreres, F; Magalhães, S C Q; Gil-Izquierdo, A; Valentão, P; Cabrita, A R J; Fonseca, A J M; Andrade, P B

    2017-01-01

    Lathyrus cicera L. seeds are of interest for food and feed purposes. Despite the recognized antioxidant activity of the seeds, arising from the phenolic fraction, their phenolic compounds have not been studied in depth yet. Therefore, to determine the phenolics profile of these seeds, a target analysis was performed using high-performance liquid chromatography coupled to photodiode-array detection and electrospray ionization/ion trap mass spectrometry (HPLC-DAD-ESI/MS(n)). Thirty-seven glycosylated flavonoids were identified for the first time in the seeds of this species and, according to their MS fragmentation, clustered in flavonol-3-O-di-/tri-glycosides-7-O-rhamnosides and other flavonol-glycosides, and flavonol-3-O-(cinnamoyl)glycoside-7-O-rhamnosides, flavonol-3-O-(dihydrophaseoyl, cinnamoyl)glycoside-7-O-rhamnosides and flavonol-3-O-(malonyl)glycoside-7-O-rhamnosides. Glycosides of kaempferol were the main flavonoids found (10 non-acylated and 21 acylated), followed by those of quercetin (3) and those of isorhamnetin, apigenin and luteolin (1). The most abundant flavonols were identified as kaempferol-3-O-(2-hexosyl)hexoside-7-O-rhamnosides. The methodology used allowed to increase the knowledge on a relevant phytochemical class of seeds from L. cicera. PMID:27507525

  9. Cerebral nuclei distribution study of dehydrodiisoeugenol as an anxiogenic agent determined by RP-HPLC.

    PubMed

    Zhang, You-Bo; Zhu, Li-Qiao; Yang, Xiu-Wei

    2013-01-01

    A sensitive RP-HPLC-DAD method was established to quantify dehydrodiisoeugenol (DDIE) in rat cerebral nuclei. The assay procedure involved one-step extraction of DDIE and daidzein, as an internal standard, from rat plasma and various cerebral nuclei with ethyl acetate. Chromatographic separation was performed on a Diamonsil™ ODS C(18) column with methanol-water (81:19, v/v) as a mobile phase. The UV absorbance of the samples was measured at the wavelength of 270nm. The analysis method was proved to be precise and accurate at linearity ranges in plasma and each cerebral nucleus with correlation coefficients of ≥0.9971. The results indicated that the method established was successfully applied to cerebral nuclei distribution study of DDIE after intravenous administration at a single dose of 40mg/kg to rat. DDIE showed high concentration in all of cerebral nuclei at 8min, which indicated that DDIE could cross the blood-brain barrier rapidly and might be one of the main bioactive substances of nutmeg. The results provide fundamental data for evaluating the effects of DDIE on the central nervous system and to be developed into an effective anxiogenic agent. PMID:23059843

  10. Microfluidic HPLC-Chip devices with integral channels containing methylstyrenic-based monolithic media.

    PubMed

    Robotti, Karla M; Yin, Hongfeng; Brennen, Reid; Trojer, Lukas; Killeen, Kevin

    2009-10-01

    Polyimide HPLC-Chip devices containing poly(methylstyrene-bis-p-vinylphenyl)ethane (MS/BVPE) stationary phase within the device channels and with wall attachment were prepared by thermally initiated free radical polymerization. The microfluidic devices were coupled to both UV and MS detectors. The potential of the MS/BVPE monolith as an alternative separation media within chip devices was investigated by side-by-side comparisons to particulate media within commercial devices. The chromatographic behavior of this stationary phase was comparable to particulate media for separations of proteins as the average peak width at half-height was equal (6.2 s) for a separation within 8 min under gradient elution conditions. The ability to control the porosity characteristics of the MS/BVPE monolith with changes in polymerization time also extended its utility into small analyte (< 500 Da) applications, although more optimization is needed to match conventional RP media for these applications. The good mechanical stability of the MS/BVPE monolith within the microdevices enabled excellent run-to-run repeatability (%RSD retention time (< or = 0.16) and chip-to-chip reproducibility (%RSD retention time (1.4). The use of this material within enrichment channels also shows its potential value in more complex work flows. PMID:19777457

  11. Isolation of 163Ho from dysprosium target material by HPLC for neutrino mass measurements

    DOE PAGESBeta

    Mocko, Veronika; Taylor, Wayne  A.; Nortier, Francois M.; Engle, Jonathan  W.; Barnhart, Todd  E.; Nickles, Robert  J.; Pollington, Anthony  D.; Kunde, Gerd  J.; Rabin, Michael  W.; Birnbaum, Eva  R.

    2015-04-29

    The rare earth isotope 163Ho is of interest for neutrino mass measurements. This report describes the isolation of 163Ho from a proton-irradiated dysprosium target and its purification. A Dy metal target was irradiated with 16 MeV protons for 10 h. After target dissolution, 163Ho was separated from the bulk Dy via cation-exchange high performance liquid chromatography using 70 mmol dm–3 α-hydroxyisobutyric acid as the mobile phase. Subsequent purification of the collected Ho fraction was performed to remove the α-hydroxyisobutyrate chelating agent and to concentrate the Ho in a low ionic strength aqueous matrix. The final solution was characterized by MC-ICP-MSmore » to determine the 163Ho/165Ho ratio, 163Ho and the residual Dy content. The HPLC purification process resulted in a decontamination factor 1.4E5 for Dy. As a result, the isolated Ho fraction contained 24.8 ±1.3 ng of 163Ho corresponding to holmium recovery of 72 ± 3%.« less

  12. Determination of the biotin content of select foods using accurate and sensitive HPLC/avidin binding

    PubMed Central

    Staggs, C.G.; Sealey, W.M.; McCabe, B.J.; Teague, A.M.; Mock, D.M.

    2006-01-01

    Assessing dietary biotin content, biotin bioavailability, and resulting biotin status are crucial in determining whether biotin deficiency is teratogenic in humans. Accuracy in estimating dietary biotin is limited both by data gaps in food composition tables and by inaccuracies in published data. The present study applied sensitive and specific analytical techniques to determine values for biotin content in a select group of foods. Total biotin content of 87 foods was determined using acid hydrolysis and the HPLC/avidin-binding assay. These values are consistent with published values in that meat, fish, poultry, egg, dairy, and some vegetables are relatively rich sources of biotin. However, these biotin values disagreed substantially with published values for many foods. Assay values varied between 247 times greater than published values for a given food to as much as 36% less than the published biotin value. Among 51 foods assayed for which published values were available, only seven agreed within analytical variability (720%). We conclude that published values for biotin content of foods are likely to be inaccurate. PMID:16648879

  13. Improvement in HPLC separation of acetic acid and levulinic acid in the profiling of biomass hydrolysate.

    PubMed

    Xie, Rui; Tu, Maobing; Wu, Yonnie; Adhikari, Sushil

    2011-04-01

    5-Hydroxymethylfurfural (HMF) and furfural could be separated by the Aminex HPX-87H column chromatography, however, the separation and quantification of acetic acid and levulinic acid in biomass hydrolysate have been difficult with this method. In present study, the HPLC separation of acetic acid and levulinic acid on Aminex HPX-87H column has been investigated by varying column temperature, flow rate, and sulfuric acid content in the mobile phase. The column temperature was found critical in resolving acetic acid and levulinic acid. The resolution for two acids increased dramatically from 0.42 to 1.86 when the column temperature was lowered from 60 to 30 °C. So did the capacity factors for levulinic acid that was increased from 1.20 to 1.44 as the column temperature dropped. The optimum column temperature for the separation was found at 45 °C. Variation in flow rate and sulfuric acid concentration improved not as much as the column temperature did. PMID:21316945

  14. Development and validation of an HPLC method to determine metabolites of 5-hydroxymethylfurfural (5-HMF).

    PubMed

    Hardt-Stremayr, Magdalena; Bernaskova, Marketa; Hauser, Stefanie; Kunert, Olaf; Guo, Xinghua; Stephan, Janette; Spreitz, Josef; Lankmayr, Ernst; Schmid, Martin G; Wintersteiger, Reinhold

    2012-10-01

    The food component 5-hydroxymethylfurfural is supposed to have antioxidative properties and is therefore used as an acting agent in a novel anticancer infusion solution, named Karal®, and an oral supplementation. Previous studies showed that after oral and intravenous application, the substance is completely decomposed to its metabolites: 5-hydroxymethylfuroic acid, 2,5-furandicarboxylic acid, and N-(hydroxymethyl)furoyl glycine. The formation of a fourth metabolite, namely 5-sulphoxymethylfurfural, is still not clarified according to literature. Due to commercial unavailability, synthesis of 5-sulphoxymethylfurfural was conducted and a synthesis procedure for N-(hydroxymethyl)furoyl glycine had to be developed. Identification of the synthesised compounds was proven by LC-MS and NMR. An appropriate HPLC method was established to obtain good separation of the four possible metabolic substances and 5-hydroxymethylfurfural within 12 min via a HILIC column (150 × 4.6 mm, 5 μm) using a gradient grade system switching from mobile phase A (ACN/ammonium formate 100 mM, pH 2.35, 95:5, v/v) to mobile phase B (ACN/ammonium formate 100 mM, pH 2.35, 85:15, v/v). The procedure was afterward validated following ICH guidelines in terms of selectivity, linearity, precision, LOD, and LOQ. PMID:22941583

  15. Validation of a HPLC method for determination of hydroxymethylfurfural in crude palm oil.

    PubMed

    Ariffin, Abdul Azis; Ghazali, H M; Kavousi, Parviz

    2014-07-01

    For the first time 5-hydroxymethyl-2-furaldehyde (HMF) was separated from crude palm oil (CPO), and its authenticity was determined using an RP-HPLC method. Separation was accomplished with isocratic elution of a mobile phase comprising water and methanol (92:8 v/v) on a Purospher Star RP-18e column (250mm×4.6mm, 5.0μm). The flow rate was adjusted to 1ml/min and detection was performed at 284nm. The method was validated, and results obtained exhibit a good recovery (95.58% to 98.39%). Assessment of precision showed that the relative standard deviations (RSD%) of retention times and peak areas of spiked samples were less than 0.59% and 2.66%, respectively. Further, the limit of detection (LOD) and LOQ were 0.02, 0.05mg/kg, respectively, and the response was linear across the applied ranges. The crude palm oil samples analysed exhibited HMF content less than 2.27mg/kg. PMID:24518321

  16. HPLC Quantification of 4-Nitrophenol and its Conjugated Metabolites from Bile

    PubMed Central

    Almási, Attila; Fischer, Emil; Perjési, Pál

    2011-01-01

    An isocratic ion pair RP-HPLC method with UV-Vis detection has been developed and validated for simultaneous analysis of 4-nitrophenol (PNP), 4-nitrophenyl β-glucuronide (PNP-G), and 4-nitrophenyl sulfate (PNP-S) in rat bile samples using 4-ethylphenol (ETP) as internal standard. Chromatographic separation was achieved on a C18 column by isocratic elution with a mobile phase consisted of methanol-0.01 M citrate buffer pH 6.2 (47:53 v/v) containing 0.03 M TBAB. The flow rate was 1.0 ml min−1, the detection was affected at 290 nm. Calibration plots were generated over the concentration range 1–100 μM PNP, PNP-G, PNP-S with a common lower limit of quantification of 2.5 μM. Intra- and inter-day precision and repeatability were determined at six different concentrations. Results obtained by application of the method for determination of PNP, PNP-G and PNP-S in bile fractions collected during intestinal perfusion of PNP in hyperglycemic rats are presented. PMID:22145108

  17. Analysis of residual products in triethylbenzylammonium chloride by HPLC. Study of the retention mechanism.

    PubMed

    Prieto-Blanco, M C; López-Mahía, P; Prada-Rodríguez, D

    2006-04-01

    The control of industrial products for minimization of their impact on the environment and human health requires the development of specific analysis methods. Information provided by these methods about toxic components, by-products, and other derivatives may also be useful to reduce the possible impact of industrial products. The studied compound in this paper, triethylbenzylammonium chloride (TEBA), is mainly used in industrial synthesis. This quaternary compound and its residual products coming from quaternization reaction (benzyl chloride, benzaldehyde, and benzyl alcohol) are analyzed by HPLC. The separation is based on control of the silanophilic contribution to TEBA retention because of the quaternary nature of this compound. The effect of the three buffers (sodium acetate, ammonium acetate, and sodium formate) and their concentrations in the chromatographic behavior of the quaternary compound is examined. The buffer cation and anion regulate TEBA retention. Also, the concentration of the quaternary compound is another parameter that had influence in some aspects of its chromatographic behavior (e.g., retention and symmetry). The proposed method is applied to TEBA synthesis along, with the formation and removal of impurities with the results compared with those obtained for the quaternary compound benzalkonium chloride. PMID:16620516

  18. HPLC-fluorescence determination of individual free and conjugated bile acids in human serum.

    PubMed

    Gatti, R; Roda, A; Cerre, C; Bonazzi, D; Cavrini, V

    1997-01-01

    A method for the quantitative analysis of unconjugated and conjugated bile acids (BA) in serum of patients with primary biliary cirrhosis (PBC) before and after therapy with antibiotic or ursodeoxycholic acid (UDCA) is described. After separation of the free, glycine and taurine conjugated (F, G and T conjugated) fractions by solid-phase extraction, the isolated T conjugates were hydrolysed enzymatically using cholyglycine hydrolase. The BA fractions were derivatized using 2-bromoacetyl-6-methoxynaphthalene (Br-AMN) and detected fluorimetrically (lambda exc = 300 nm, lambda em = 460 nm). The derivatization reaction was performed under mild conditions (10 min at 40 degrees C) in an aqueous medium in the presence of tetrakis (decyl) ammonium bromide (TDeABr). The HPLC separation was achieved using an ODS column and with a mobile phase gradient mixture of A-B, where A is water and B is acetonitrile:methanol (60:40 v/v) for elution at a flow-rate of 1.2 mL/min. The reproducibility, recovery and separation of individual BA under gradient elution conditions were satisfactory, allowing a sensitive detection of each BA in serum samples with a detection limit of about 1-2 pmol. PMID:9051208

  19. Determination of melamine in dairy products using electromembrane-LPME followed by HPLC.

    PubMed

    Fashi, Armin; Yaftian, Mohammad Reza; Zamani, Abbasali

    2015-12-01

    This study presents the application of electromembrane microextraction technique combined with HPLC-UV detection for fast extraction-preconcentration and determination of melamine in dairy products. It is based on the extraction of charged melamine molecules migrated from 6.5 mL feed solution through a liquid membrane immobilized in the pores of a hollow fiber into 20 μL of the acceptor solution. The best performance was achieved by using 2-nitrophenyloctylether, tris-(2-ethylhexyl) phosphate (10%) and di-(2-ethylhexyl)phosphate (10%) as the extraction solvent; application of a potential of 90 V as the driving force and by adjusting the pH of feed and receiving phases at 5.5 and 1, respectively. The working range was 7-8000 ng mL(-1), with detection limit of 2.0-5.8 ng mL(-1). The enrichment factor was in the range 82-192. Intra- and inter-day relative standard deviations were less than 6.6%. Extraction and relative recoveries for different samples were between 25-59% and 85-95%, respectively. PMID:26041169

  20. Derivatization Strategy for the Comprehensive Characterization of Endogenous Fatty Aldehydes Using HPLC-Multiple Reaction Monitoring.

    PubMed

    Tie, Cai; Hu, Ting; Jia, Zhi-Xin; Zhang, Jin-Lan

    2016-08-01

    Fatty aldehydes are crucial substances that mediate a wide range of vital physiological functions, particularly lipid peroxidation. Fatty aldehydes such as acrolein and 4-hydroxynonenal (4-HNE) are considered potential biomarkers of myocardial ischemia and dementia, but analytical techniques for fatty aldehydes are lacking. In the present study, a comprehensive characterization strategy with high sensitivity and facility for fatty aldehydes based on derivatization and high-performance liquid chromatography-multiple reaction monitoring (HPLC-MRM) was developed. The fatty aldehydes of a biosample were derivatized using 2,4-bis(diethylamino)-6-hydrazino-1,3,5-triazine under mild and efficient reaction conditions at 37 °C for 15 min. The limit of detection (LOD) of the fatty aldehydes varied from 0.1 to 1 pg/mL, depending on the structures of these molecules. General MRM parameters were forged for the analysis of endogenous fatty aldehydes. "Heavy" derivatization reagents with 20 deuterium atoms were synthesized for both the discovery and comprehensive characterization of fatty aldehydes. More than 80 fatty aldehydes were detected in the biosamples. The new strategy was successfully implemented in global fatty aldehyde profiling of plasma and brain tissue of the bilateral common carotid artery (2VO) dementia rat model. Dozens of fatty aldehydes were significantly changed between the control and model groups. These findings further highlight the importance of endogenous fatty aldehydes. PMID:27397858

  1. Investigation of red natural dyes used in historical objects by HPLC-DAD-MS.

    PubMed

    Karapanagiotis, Ioannis; Chryssoulakis, Yannis

    2006-01-01

    High performance liquid chromatography (HPLC) with UV-Vis Diode Array Detection (DAD) and electrospray mass spectrometric (ESI-MS) method was utilized for the identification of coloring components of madder, Armenian and Mexican cochineal, lac dye, brazilwood, safflower and dragon blood--probably the most important red natural dyestuffs found in objects of the cultural heritage. UV-Vis detection limits in the range of 0.2-0.6 ng for carminic acid, alizarin and purpurin were achieved using a gradient elution of H2O-0.01% TFA and CH3CN-0.01% TFA. ESI mass spectrometer was also used, as a supportive detection method to the standard DAD, for further analysis of the tested materials, with the ability to analyze dyestuffs as small as one milligram. The presence of madder was revealed in two historical (Hellenistic and Roman period) samples, found in the Mediterranean area, by identifying purpurin in both of them. Munjistin was also identified in one of the samples (Hellenistic period) while alizarin was not detected, raising questions regarding the exact madder type, utilized in the historical samples. PMID:16736555

  2. [Simultaneous determination of rosmarinic acid, oridonin and chrysoplenetin in Isodon rubescens by HPLC].

    PubMed

    Yuan, Xing-Li; Yan, Li-Hua; Zhang, Qi-Wei; Wang, Zhi-Min

    2013-07-01

    An HPLC method was developed for simultaneous quantitation of rosmarinic acid, oridonin and chrysoplenetin in the aerial parts of Isodon rubescens. Samples were analyzed on an Ultimate C18 column (4.6 mm x 250 mm, 5 microm) with methanol and water containing 0.1% formic acid as mobile phases in a linear gradient mode. The flow rate was 1.0 mL x min(-1) and the temperature was set at 30 degrees C. The PDA detector wavelengths were set at 338 nm for rosmarinic and chrysoplenetin and at 242 nm for oridonin. The linear ranges were 0.222-2.78, 0.227-2.84 and 0.005-0.071 microg for rosmarinic acid, oridonin and chrysoplenetin, respectively. The average recoveries of the three constituents were 102.9% (RSD 1.9%), 99.6% (RSD 1.1%) and 102.5% (RSD 0.94%), respectively. This method was proved to be accurate and repeatable, and can be used for quality control of the aerial parts of I. rubescens. PMID:24199569

  3. 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; Barlow, Ray; Sessions, Heather; Ismail, Hassan; Perl, Jason

    2009-01-01

    Seven international laboratories specializing in the determination of marine pigment concentrations using high performance liquid chromatography (HPLC) were intercompared using in situ samples and a mixed pigment sample. The field samples were collected primarily from oligotrophic waters, although mesotrophic and eutrophic waters were also sampled to create a dynamic range in chlorophyll concentration spanning approximately two orders of magnitude (0.020 1.366 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) the reduction in uncertainties as a result of applying quality assurance (QA) procedures; c) the importance of establishing a properly defined referencing system in the computation of uncertainties; d) the analytical benefits of performance metrics, and e) the utility of a laboratory mix in understanding method performance. 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.

  4. Stability-indicating HPLC determination of trandolapril in bulk drug and pharmaceutical dosage forms.

    PubMed

    Al-Hawash, Leena A; Shakya, Ashok K; Saleem, Maher L

    2015-01-01

    A rapid, simple, accurate, precise, economical, robust, and stability indicating reverse phase HPLC-PDA procedure has been developed and validated for the determination of trandolapril. The trandolapril was separated isocratically on Hypersil-Gold C18 column (250 mm × 4.6 mm, 5 μm) with a mobile phase consisting of 50% acetonitrile and 50% water (containing 0.025% triethylamine, pH 3.0 ± 0.1), at 25 ± 2°C. Retention time of the drug was ~4.6 min. The eluted compounds were monitored and identified at 210 nm. The linearity of the method was excellent (r (2) > 0.9999) over the concentration range of 1-24 μg/mL; the limit of detection (LOD) and limit of quantitation (LOQ) were 0.0566 μg/mL and 0.1715 μg/mL, respectively. The overall precision was less than 2%. Mean recovery of trandolapril was more than 99%; no interference was found from the component present in the preparation. Stability studies indicate that the drug was stable to sunlight and UV light. The drug gives 6 different oxidative products on exposure to hydrogen peroxide. Slight degradation was observed in acidic condition. Degradation was higher in the alkaline condition compared to other conditions. The robustness of the method was studied using factorial design experiment. PMID:25802524

  5. An improved extraction method for the HPLC determination of morphine and its metabolites in plasma.

    PubMed

    Pawula, M; Barrett, D A; Shaw, P N

    1993-01-01

    A new, simple and rapid extraction procedure coupled with a combined coulometric-fluorescence HPLC assay is described for the simultaneous determination of morphine (M) and morphine-3-glucuronide (M3G), morphine-6-glucuronide (M6G), and normorphine (NM) in plasma. The effect of concentration and pH of selected ion-pairing agents on the extraction of these compounds from plasma by solid-phase extraction was investigated. The extraction procedure was optimized in terms of recovery, reproducibility and lack of interference from endogenous materials. The optimized method uses tetrabutylammonium hydrogen sulphate (TBAHS) at pH 10 followed by separation on a single C18 solid-phase extraction cartridge. For routine analysis the procedure provides high and reproducible recoveries over a concentration range of 1.0-1000 ng ml-1 for morphine, M6G and normorphine and 20-1000 ng ml-1 for M3G. The method was used successfully to analyse plasma samples from a pharmacokinetic study in which sheep had received an intravenous dose of 0.015 mg kg-1 of M6G. PMID:8357878

  6. Determination of Saponin Content in Hang Maidong and Chuan Maidong via HPLC-ELSD Analysis

    PubMed Central

    Li, Xian-En; Wang, Yu-Xia; Sun, Peng; Liao, Deng-Qun

    2016-01-01

    Zhejiang and Sichuan are regarded as two genuine producing areas of Ophiopogonis radix in China. To study the difference in the quality of Ophiopogonis radix from these two places, the contents of three reported bioactive saponins, that is, ophiopogonins B, D, and D′, in tubers and fibrous roots of Ophiopogon japonicus from Cixi city of Zhejiang and Santai county of Sichuan were quantified using HPLC-ELSD method and compared. Ophiopogonin B and ophiopogonin D′ content in tubers of HMD were higher than those in radix of CMD, whereas ophiopogonin D in HMD was about twice lower than that of CMD. Three ophiopogonins were all detected in fibrous roots of both HMD and CMD. Their averaged content in fibrous roots of CMD was about twice higher than that in tubers of CMD. Ophiopogonin D in fibrous roots of CMD was about five times higher than that of HMD. Our biochemical assay revealed that fibrous roots and tubers of CMD can be of an important saponin source, especially for ophiopogonin D. PMID:26925295

  7. Submerged fermentation production and characterization of intracellular triterpenoids from Ganoderma lucidum using HPLC-ESI-MS.

    PubMed

    Cui, Mei-lin; Yang, Huan-yi; He, Guo-qing

    2015-12-01

    As the main bioactive metabolites of Ganoderma lucidum, triterpenoids have various pharmacological effects. In this paper, the nutritional requirements and culture conditions of a submerged culture of G. lucidum were optimized using the response surface methodology; maximum mycelia biomass and intracellular triterpenoid production reached 1.87 g/100 ml and 93.21 mg/100 ml, respectively, for a culture consisting of wort 4.10% (0.041 g/ml) and yeast extract 1.89% (0.0189 g/ml), pH 5.40. For the first time, we established that wort, which is cheap and abundant, can replace the more commonly used glucose as the sole source of carbohydrate. Using high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS), 10 major ganoderic acids were tentatively identified based on the predominant fragmentation pathways with the elimination of H2O and CO2, as well as cleavage of the D-ring. PMID:26642183

  8. Dispersive Liquid-Liquid Microextraction for HPLC-UV Determination of PAHs in Milk.

    PubMed

    Mahmoudpour, Mansour; Mohtadinia, Javad; Ansarin, Masood; Nemati, Mahboob

    2016-03-01

    A simple and rapid analytical method for the extraction and quantification of four polycyclic aromatic hydrocarbons in milk sample has been developed using dispersive liquid-liquid microextraction followed by the use of HPLC. Benzo(a)pyrene, benzo(a)anthracene, and benzo(b)fluoranthene were used as model compounds; the milk sample was spiked with these compounds to assess the extraction procedure. Experimental parameters that influence the extraction efficiency, including the nature and volume of the disperser and extraction solvents, pH, and the volume of milk sample, were optimized. Under the optimum extraction conditions (extraction solvent: chloroform, 200 μL; dispersive solvent: acetonitrile, 700 μL; and extraction time 5 s or less), the performance of the proposed method was evaluated. The chromatographic peak area was linear with concentrations in the range of 0.2-10 ng/mL(-1) and with correlation coefficients ranging from 0.9968 to 0.9985. The LODs, based on a S/N ratio of 3, ranged from 0.06 to 0.18 ng/mL(-1). The RSDs varied from 3.68 to 9.7% (n = 3). The recoveries of these compounds were from 88.38 to 100%. The performance of the present method was evaluated for the determination of polycyclic aromatic hydrocarbons in various types of milk samples. PMID:26960830

  9. Determination of melamine in powdered milk by molecularly imprinted stir bar sorptive extraction coupled with HPLC.

    PubMed

    Zhu, Ling; Xu, Guanhong; Wei, Fangdi; Yang, Jing; Hu, Qin

    2015-09-15

    A novel molecularly imprinted stir bar (MIP-SB) was developed with melamine (MA) as the template molecule in this study. The sorptive capacity of MIP-SB was nearly three times over that of non-imprinted stir bar (NIP-SB). The MIP-SB presented much better selectivity than NIP-SB when used to absorb MA and its analogues. An analytical method to determine MA in powdered milk was established by combining MIP-SB sorptive extraction with HPLC. The liner range was 0.0631-12.6ng/mL with good correlation coefficient of 0.9983, and the limit of detection was 0.0127ng/mL based on three times ratio of signal to noise. This method was successfully applied to the determination of MA in powdered milk with satisfactory results. The method built is simple and suitable for the determination of MA in milk products which is of great significance for quality control of milk products. PMID:26001132

  10. [Multiresidue determination of quinolones in animal and fishery products by HPLC].

    PubMed

    Chonan, Takao; Fujimoto, Toru; Inoue, Maki; Tazawa, Teijiro; Ogawa, Hiroshi

    2008-06-01

    A simple and rapid multiresidue method was developed for the determination of twelve quinolones (ciprofloxacin, danofloxacin, difloxacin, enrofloxacin, flumequine, marbofloxacin, nalidixic acid, norfloxacin, ofloxacin, orbifloxacin, oxolinic acid and sarafloxacin) in muscle, liver, chicken eggs, milk, prawn and rainbow trout. The quinolones were extracted from a sample with acetonitrile-water (95 : 5). A fifth part of the filtered extract was diluted with water to keep the acetonitrile ratio at ca. 60%, and passed through a C18 mini-column. The eluate was evaporated to dryness, and the residues were dissolved in methanol-water (30 : 70) for HPLC analysis. The quinolones were separated on a Inertsil ODS-3V column (4.6 mm i.d.x250 mm) with a gradient system of 0.1% phosphoric acid-acetonitrile as the mobile phase, with fluorescence detection.No interfering peak was found on the chromatograms of animal and fishery products, except for milk. The recoveries of the quinolones were over 60% from the animal and fishery products fortified at 0.1 microg/g, and the quantification limits of the quinolones were 0.005 microg/g. This proposed method was found to be effective and suitable for the screening of the quinolones in animal and fishery products. PMID:18633210

  11. Systematic optimization of an SPE with HPLC-FLD method for fluoroquinolone detection in wastewater.

    PubMed

    He, Ke; Blaney, Lee

    2015-01-23

    This paper describes a selective and ultra-sensitive analytical method for simultaneous determination of 11 fluoroquinolone (FQ) antibiotics in environmental and wastewater samples. The method employs offline solid-phase extraction (SPE) and reversed-phase high performance liquid chromatography with fluorescence detection (HPLC-FLD). A weak cation exchange SPE protocol was developed with a novel loading volume optimization algorithm and a methanol cleanup step to remove background organic matter. Various parameters were optimized to recover FQs from water/wastewater and analyte recovery was generally greater than 80%. Chromatographic separation of the 11 FQs was achieved on a 150 mm pentafluorophenyl column using a gradient elution scheme with methanol, acetonitrile, and 20mM phosphate buffer (pH=2.4). Excitation and emission wavelengths were individually optimized for each FQ using fluorescence spectroscopy; the excitation and emission wavelengths were 276-296 nm and 444-506 nm, respectively. Instrumental quantitation limits were 20-100 pg of mass injected. Of the 11 FQs investigated, seven (i.e., ciprofloxacin, difloxacin, enrofloxacin, fleroxacin, norfloxacin, moxifloxacin, and ofloxacin) were detected during a four-month sampling campaign of wastewater and wastewater-impacted surface water. Concentrations of FQs in raw wastewater, wastewater effluent, and wastewater-impacted surface water were 5-1292, 2-504, and 4-187ng/L, respectively. PMID:25200119

  12. HPLC-UV method validation for the identification and quantification of bioactive amines in commercial eggs.

    PubMed

    de Figueiredo, Tadeu Chaves; de Assis, Débora Cristina Sampaio; Menezes, Liliane Denize Miranda; da Silva, Guilherme Resende; Lanza, Isabela Pereira; Heneine, Luiz Guilherme Dias; Cançado, Silvana de Vasconcelos

    2015-09-01

    A quantitative and confirmatory high-performance liquid chromatography with ultraviolet detection (HPLC-UV) method for the determination of bioactive amines in the albumen and yolk of commercial eggs was developed, optimized and validated by analyte extraction with trichloroacetic acid and pre-column derivatization with dansyl chloride. Phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine and spermine standards were used to evaluate the following performance parameters: limit of detection (LoD), limit of quantification (LoQ), selectivity, linearity, precision, recovery and ruggedness. The LoD of the method was defined from 0.2 to 0.3 mg kg(-1) for the yolk matrix and from 0.2 to 0.4 mg kg(-1) for the albumen matrix; the LoQ was from 0.7 to 1.0 mg kg(-1) for the yolk matrix and from 0.7 to 1.1 mg kg(-1) for the albumen matrix. The validated method exhibited excellent selectivity and separation of all amines with coefficients of determination higher than 0.99. The obtained recovery values were from 90.5% to 108.3%, and the relative standard deviation (RSD) was lower than 10% under repeatability conditions for the studied analytes. The performance parameters show the validated method to be adequate for the determination of bioactive amines in egg albumen and yolk. PMID:26003718

  13. Bioanalysis and pharmacokinetics of chitosan ester in rabbit serum by HPLC with postcolumn fluorescence derivatization.

    PubMed

    Han, Yuhong; Lv, Zhihua; Jiang, Tingfu; Wang, Yuanhong

    2007-01-01

    Interest in antiatherosclerotic activity of chitosan ester (PS916) with a new form of sulfate amino polysaccharide derived from marine chitin has necessitated the development of a sensitive and specific method to study its pharmacokinetics. A sensitive and reproducible high-performance liquid chromatography (HPLC) with postcolumn fluorescence derivatization method was developed and validated for the determination of PS916 in rabbit serum. Chromatography was carried out using a C8 reversed-phase column with an isocratic mobile phase consisting of methanol-water (20:80, v/v) at a flow rate of 0.2 ml/min. The derivatization procedure involved postcolumn reaction with guanidine hydrochloride in an alkaline medium at 110 degrees C. The fluorometric detector was operated at 250 nm (excitation) and 435 nm (emission). The assay was linear over the concentration range of 5-100 microg/ml. The lower limit of detection (LLOD) was found to be 1.0 microg/ml. The proposed method was successfully applied for a pharmacokinetic study of PS916 in rabbits. PMID:16920411

  14. Specific and rapid analysis of ubiquinones using Craven's reaction and HPLC with postcolumn derivatization.

    PubMed

    Shimada, Haruo; Kodjabachian, David; Ishida, Masami

    2007-09-01

    A new method for the analysis of ubiquinones in various samples was developed using an HPLC system with postcolumn derivatization. Craven's reaction, a specific color reaction for the analysis of ubiquinones, was used in the system. Because the reaction progressed in organic solvents that contained ubiquinones and ethylcyanoacetate under an alkaline condition, the selectivity for ubiquinone detection was higher than that for ubiquinone detection using the nonderivatized ultraviolet detection system at 275 nm, a system widely used for the analysis of ubiquinones. The new detection system can avoid the adverse effects of impurities. Furthermore, it can confirm specificity by stopping the color reaction under a neutral condition. The detection limit for ubiquinone-10 was 1 ng (1.2 pmol). A good linearity for the calibration curve was observed in the range of 11.7 pmol to 11.7 nmol. To investigate the possible application of this method, various samples, such as soybean capsules used as a dietary supplement and biological materials (rice as well as bovine plasma and liver samples), were applied to the system and their ubiquinone contents were quantified. This method is thought to be widely and conveniently applicable for determining the level of ubiquinones because of its high selectivity for ubiquinone detection. PMID:17579247

  15. Determination of Ophiopogon japonicus polysaccharide in plasma by HPLC with modified postcolumn fluorescence derivatization.

    PubMed

    Lin, Xiao; Xu, De-Sheng; Feng, Yi; Shen, Lan

    2005-07-15

    Interest in antimyocardial ischemic activity of a graminan-type fructosan with an average molecular weight of 5,000 Da from Ophiopogon japonicus (FOJ-5) has necessitated the development of a sensitive and specific method to study its pharmacokinetics. An HPLC method with modified postcolumn fluorescence derivatization to determine FOJ-5 in plasma was developed in this study. The Shodex Sugar KS-802 high-performance gel column was chosen for separating FOJ-5 from its degradation products and endogenous carbohydrates. The postcolumn procedure involved acid hydrolysis of the column eluate at 150 degrees C, which decreased the detection limit for FOJ-5 from 1 microg to 25 ng, followed by fluorometric reaction with guanidine in an alkaline medium at 90 degrees C. The clearance of FOJ-5 from the bodies of rats following intravenous injection displayed a complex type of kinetics involving at least two compartments, and the half-life of the elimination of FOJ-5 from plasma administered at 15 mg/kg (18.1 min) was quicker than that administered at 50mg/kg (28.9 min). This modified approach can also be used for microanalysis of both nonreducing oligosaccharides and other neutral polysaccharides. PMID:15935322

  16. Importance of the ionization states of m-THPC for its HPLC fluorescence detection.

    PubMed

    Desroches, M C; Bourdon, O; Morokro, Y; Chaminade, P; Blais, J; Prognon, P; Kasselouri, A

    2001-01-01

    An original, rapid and sensitive high-performance liquid chromatographic (HPLC) method has been developed for the detection of 5, 10, 15, 20 tetra-meso-hydroxyphenylchlorine (m-THPC), a photosensitizer used in the photodynamic therapy (PDT) of cancers. Chromatographic separation was carried out on a C(8) Zorbax column (80 x 4 mm, 5 microm). The mobile phase was an ethanol/aqueous sulphuric acid, pH 2.0 (65/35 v/v), in an isocratic mode yielding to rapid analysis (3.1 min) with narrow peaks. As the fluorescence intensity was found to be highly pH-dependent and to increase with pH values, a post-column device prior to the fluorescence detection (lambda(exc) = 423 nm, lambda(em) = 650 nm) was used to allow the addition of a 0.05 mol/L Na(2)HPO(4) solution to the mobile phase. Compared to standard conditions, a 300% increase of the fluorescence intensity was obtained for optimized operating conditions using experimental design. The validation of this analytical method showed that the response function was linear for concentrations up to 1000 microg/L (1.47 x 10(-6) mol/L) with a detection limit of 188 pg (S/N = 3). PMID:11312544

  17. Analysis of Tetracyclines in Medicated Feed for Food Animal Production by HPLC-MS/MS

    PubMed Central

    Gavilán, Rosa Elvira; Nebot, Carolina; Miranda, Jose Manuel; Martín-Gómez, Yolanda; Vázquez-Belda, Beatriz; Franco, Carlos Manuel; Cepeda, Alberto

    2015-01-01

    The use of medicated feed is a common practice in animal food production to improve animal health. Tetracyclines and β-Lactams are the groups that are most frequently added to this type of feed. The measurement of the concentration of the analytes in these types of samples is sometimes due to the matrix characteristic, and manufacturers are demanding fast, precise and reproducible methods. A rapid confirmatory method based on a simple extraction protocol using acidified methanol and followed by high performance liquid chromatography coupled to a tandem mass spectrometer for the quantification of four tetracyclines in feed is presented. Validation was performed following the guidelines of Decision 2002/657/EC. Results indicated that the four tetracyclines can be identified and quantified in a concentration range between 50 and 500 mg/kg with recoveries between 84% and 109% and RSD for precision under reproducible conditions between 12% and 16%. Satisfactory results were also obtained with interlaboratory studies and by comparing the method with an HPLC-Fluorescent method. PMID:27025516

  18. Development and Validation of Stability-indicating HPLC Method for Simultaneous Estimation of Cefixime and Linezolid

    PubMed Central

    Patel, Nidhi S.; Tandel, Falguni B.; Patel, Yogita D.; Thakkar, Kartavya B.

    2014-01-01

    A stability-indicating reverse phase high performance liquid chromatography method was developed and validated for cefixime and linezolid. The wavelength selected for quantitation was 276 nm. The method has been validated for linearity, accuracy, precision, robustness, limit of detection and limit of quantitation. Linearity was observed in the concentration range of 2-12 μg/ml for cefixime and 6-36 μg/ml for linezolid. For RP-HPLC, the separation was achieved by Phenomenex Luna C18 (250×4.6 mm) 5 μm column using phosphate buffer (pH 7):methanol (60:40 v/v) as mobile phase with flow rate 1 ml/min. The retention time of cefixime and linezolid were found to be 3.127 min and 11.986 min, respectively. During force degradation, drug product was exposed to hydrolysis (acid and base hydrolysis), H2O2, thermal degradation and photo degradation. The % degradation was found to be 10 to 20% for both cefixime and linezolid in the given condition. The method specifically estimates both the drugs in presence of all the degradants generated during forced degradation study. The developed methods were simple, specific and economic, which can be used for simultaneous estimation of cefixime and linezolid in tablet dosage form. PMID:25593387

  19. Separation of bacteriochlorophyll homologues from green photosynthetic sulfur bacteria by reversed-phase HPLC.

    PubMed

    Borrego, C M; Garcia-Gil, L J

    1994-07-01

    A reversed-phase High Performance Liquid Cromatography (HPLC) method has been developed to accurately separate bacteriochlorophyllsc, d ande homologues in a reasonably short run time of 60 minutes. By using this method, two well-defined groups of bacteriochlorophyll homologue peaks can be discriminated. The first one consists of 4 peaks (min 24 to 30), which corresponds to the four main farnesyl homologues. The second peak subset is formed by a cluster of up to 10 minor peaks (min 33 to 40). These peaks can be related with series of several alcohol esters of the different chlorosome chlorophylls. The number of homologues was, however, quite variable depending on both, the bacteriochlorophyll and the bacterial species. The method hereby described, also provides a good separation of other photosynthetic pigments, either bacterial (Bacteriochlorophylla, chlorobactene, isorenieratene and okenone) or algal ones (Chlorophylla, Pheophytina and β-carotene). A preliminary screening of the homologue composition of several green photosynthetic bacterial species and isolates, has revealed different relative quantitative patterns. These differences seem to be related to physiological aspects rather than to taxonomic ones. The application of the method to the study of natural populations avoids the typical drawbacks on the pigment identification of overlapping eukaryotic and prokaryotic phototrophic microorganisms, giving further information about their physiological status. PMID:24310022

  20. Improved analysis of dissolved carbohydrates in stream water with HPLC-PAD.

    PubMed

    Cheng, X; Kaplan, L A

    2001-02-01

    This paper describes improvements made to the determination of dissolved carbohydrates in stream water with high-performance liquid chromatography and pulsed amperometric detection (HPLC-PAD). We eliminated interference from dissolved oxygen, separated xylose and mannose along with other molecules, reduced the chromatographic peak shift associated with carbonate accumulation in the column to less than 1% for all samples, and achieved an 8% increase in recovery of hydrolyzed carbohydrates by replacing ion-exchange desalting cartridges with evaporative removal of HCl under N2. These modifications lowered detection limits to less than or equal to 0.4 nM for 10 different monosaccharides and enhanced our ability to follow the dynamics of these molecules in stream ecosystems. In the determination of dissolved free monosaccharides, average relative precision was 1.3% and recovery ranged from 92 to 109%. For dissolved total saccharides, average relative precision was 3.3%. Concentrations were stable when filtered (0.2 microm) stream water was stored for 1 day at 22 degrees C, 1 week at 4 degrees C, or 1.5 months at -20 degrees C. PMID:11217746