Application of Fourier-transform infrared (FT-IR) spectroscopy for simple and easy determination of chylomicron-triglyceride and very low density lipoprotein-triglyceride.

PubMed

Sato, Kenichi; Seimiya, Masanori; Kodera, Yoshio; Kitamura, Akihide; Nomura, Fumio

2010-02-01

Fourier-transform infrared (FT-IR) spectroscopy is a simple and reagent-free physicochemical analysis method, and is a potential alternative to more time-consuming and labor-intensive procedures. In this study, we aimed to use FT-IR spectroscopy to determine serum concentrations of chylomicron-triglyceride (TG) and very low density lipoprotein (VLDL)-TG. We analyzed a chylomicron fraction and VLDL fraction, which had been obtained by ultracentrifugation, to search for wavelengths to designate to each fraction. Then, partial least square (PLS) calibrations were developed using a training set of samples, for which TG concentrations had been determined by conventional procedures. Validation was conducted with another set of samples using the PLS model to predict serum TG concentrations on the basis of the samples' IR spectra. We analyzed a total of 150 samples. Serum concentrations of chylomicron-TG and VLDL-TG estimated by FT-IR spectroscopy agreed well with those obtained by the reference method (r=0.97 for both lipoprotein fractions). FT-IR spectrometric analysis required 15mul of serum and was completed within 1min. Serum chylomicron-TG and VLDL-TG concentrations can be determined with FT-IR spectroscopy. This rapid and simple test may have a great impact on the management of patients with dyslipidemia. Copyright 2009. Published by Elsevier B.V.

A validated Fourier transform infrared spectroscopy method for quantification of total lactones in Inula racemosa and Andrographis paniculata.

PubMed

Shivali, Garg; Praful, Lahorkar; Vijay, Gadgil

2012-01-01

Fourier transform infrared (FT-IR) spectroscopy is a technique widely used for detection and quantification of various chemical moieties. This paper describes the use of the FT-IR spectroscopy technique for the quantification of total lactones present in Inula racemosa and Andrographis paniculata. To validate the FT-IR spectroscopy method for quantification of total lactones in I. racemosa and A. paniculata. Dried and powdered I. racemosa roots and A. paniculata plant were extracted with ethanol and dried to remove ethanol completely. The ethanol extract was analysed in a KBr pellet by FT-IR spectroscopy. The FT-IR spectroscopy method was validated and compared with a known spectrophotometric method for quantification of lactones in A. paniculata. By FT-IR spectroscopy, the amount of total lactones was found to be 2.12 ± 0.47% (n = 3) in I. racemosa and 8.65 ± 0.51% (n = 3) in A. paniculata. The method showed comparable results with a known spectrophotometric method used for quantification of such lactones: 8.42 ± 0.36% (n = 3) in A. paniculata. Limits of detection and quantification for isoallantolactone were 1 µg and 10 µg respectively; for andrographolide they were 1.5 µg and 15 µg respectively. Recoveries were over 98%, with good intra- and interday repeatability: RSD ≤ 2%. The FT-IR spectroscopy method proved linear, accurate, precise and specific, with low limits of detection and quantification, for estimation of total lactones, and is less tedious than the UV spectrophotometric method for the compounds tested. This validated FT-IR spectroscopy method is readily applicable for the quality control of I. racemosa and A. paniculata. Copyright © 2011 John Wiley & Sons, Ltd.

Analysis of bacteria on steel surfaces using reflectance micro-Fourier transform infrared spectroscopy.

PubMed

Ojeda, Jesús J; Romero-González, María E; Banwart, Steven A

2009-08-01

Reflectance micro-Fourier transform infrared (FT-IR) analysis has been applied to characterize biofilm formation of Aquabacterium commune, a common microorganism present on drinking water distribution systems, onto the increasingly popular pipe material stainless steel EN1.4307. The applicability of the reflectance micro-FT-IR technique for analyzing the bacterial functional groups is discussed, and the results are compared to spectra obtained using more conventional FT-IR techniques: transmission micro-FT-IR, attenuated transmitted reflectance (ATR), and KBr pellets. The differences between the infrared spectra of wet and dried bacteria, as well as free versus attached bacteria, are also discussed. The spectra obtained using reflectance micro-FT-IR spectroscopy were comparable to those obtained using other FT-IR techniques. The absence of sample preparation, the potential to analyze intact samples, and the ability to characterize opaque and thick samples without the need to transfer the bacterial samples to an infrared transparent medium or produce a pure culture were the main advantages of reflectance micro-FT-IR spectroscopy.

In-situ chemical analyses of trans-polyisoprene by histochemical staining and Fourier transform infrared microspectroscopy in a rubber-producing plant, Eucommia ulmoides Oliver.

PubMed

Bamba, Takeshi; Fukusaki, Ei-Ichiro; Nakazawa, Yoshihisa; Kobayashi, Akio

2002-10-01

The localization of polyisoprene in young stem tissues of Eucommia ulmoides Oliver was investigated by histochemical staining and Fourier transform infrared (FT-IR) microspectroscopy. The fibrous structures were stained with Oil Red O. FT-IR microspectroscopic analysis proved that the fibrous structures were trans-polyisoprene. Granular structures stained with the dye, and characteristic absorptions at 2,960 cm(-1) and 1,430 cm(-1) in FT-IR suggested that trans-polyisoprene accumulated in the vicinity of the cambium layer. We have thus successfully shown for the first time the localization of trans-polyisoprene in plant tissues, and our histological investigation allowed us to presume the main sites of biosynthesis and accumulation of trans-rubber. Furthermore, a new technical approach, the preparation of sections using an electronic freezing unit and the in situ analysis of polyisoprene using FT-IR microspectroscopy, is demonstrated to be a promising method for determining the accumulation of polyisoprene as well as other metabolites.

Zero-crossing sampling of Fourier-transform interferograms and spectrum reconstruction using the real-zero interpolation method.

PubMed

Minami, K; Kawata, S; Minami, S

1992-10-10

The real-zero interpolation method is applied to a Fourier-transformed infrared (FT-IR) interferogram. With this method an interferogram is reconstructed from its zero-crossing information only, without the use of a long-word analog-to-digital converter. We installed a phase-locked loop circuit into an FT-IR spectrometer for oversampling the interferogram. Infrared absorption spectra of polystyrene and Mylar films were measured as binary interferograms by the FT-IR spectrometer, which was equipped with the developed circuits, and their Fourier spectra were successfully reconstructed. The relationship of the oversampling ratio to the dynamic range of the reconstructed interferogram was evaluated through computer simulations. We also discuss the problems of this method for practical applications.

Distribution of Hydroxyl Groups in Kukersite Shale Oil: Quantitative Determination Using Fourier Transform Infrared (FT-IR) Spectroscopy.

PubMed

Baird, Zachariah Steven; Oja, Vahur; Järvik, Oliver

2015-05-01

This article describes the use of Fourier transform infrared (FT-IR) spectroscopy to quantitatively measure the hydroxyl concentrations among narrow boiling shale oil cuts. Shale oil samples were from an industrial solid heat carrier retort. Reference values were measured by titration and were used to create a partial least squares regression model from FT-IR data. The model had a root mean squared error (RMSE) of 0.44 wt% OH. This method was then used to study the distribution of hydroxyl groups among more than 100 shale oil cuts, which showed that hydroxyl content increased with the average boiling point of the cut up to about 350 °C and then leveled off and decreased.

Study on Senna alata and its different extracts by Fourier transform infrared spectroscopy and two-dimensional correlation infrared spectroscopy

NASA Astrophysics Data System (ADS)

Adiana, M. A.; Mazura, M. P.

2011-04-01

Senna alata L. commonly known as candle bush belongs to the family of Fabaceae and the plant has been reported to possess anti-inflammatory, analgesic, laxative and antiplatelet-aggregating activity. In order to develop a rapid and effective analysis method for studying integrally the main constituents in the medicinal materials and their extracts, discriminating the extracts from different extraction process, comparing the categories of chemical constituents in the different extracts and monitoring the qualities of medicinal materials, we applied Fourier transform infrared spectroscopy (FT-IR) associated with second derivative infrared spectroscopy and two-dimensional infrared correlation spectroscopy (2D-IR) to study the main constituents of S. alata and its different extracts (extracted by hexane, dichloromethane, ethyl acetate and methanol in turn). The findings indicated that FT-IR and 2D-IR can provide many holistic variation rules of chemical constituents. Use of the macroscopical fingerprint characters of FT-IR and 2D-IR spectrum can identify the main chemical constituents in medicinal materials and their extracts, but also compare the components differences among similar samples. In a conclusion, FT-IR spectroscopy combined with 2D correlation analysis provides a powerful method for the quality control of traditional medicines.

Off-line real-time FTIR analysis of a process step in imipenem production

NASA Astrophysics Data System (ADS)

Boaz, Jhansi R.; Thomas, Scott M.; Meyerhoffer, Steven M.; Staskiewicz, Steven J.; Lynch, Joseph E.; Egan, Richard S.; Ellison, Dean K.

1992-08-01

We have developed an FT-IR method, using a Spectra-Tech Monit-IR 400 systems, to monitor off-line the completion of a reaction in real-time. The reaction is moisture-sensitive and analysis by more conventional methods (normal-phase HPLC) is difficult to reproduce. The FT-IR method is based on the shift of a diazo band when a conjugated beta-diketone is transformed into a silyl enol ether during the reaction. The reaction mixture is examined directly by IR and does not require sample workup. Data acquisition time is less than one minute. The method has been validated for specificity, precision and accuracy. The results obtained by the FT-IR method for known mixtures and in-process samples compare favorably with those from a normal-phase HPLC method.

FT-IR examination of the development of secondary cell wall in cotton fibers

USDA-ARS?s Scientific Manuscript database

The secondary cell wall development of cotton fibers harvested at 18, 20, 24, 28, 32, 36 and 40 days after flowering was examined using attenuated total reflection Fourier transform-infrared (ATR FT-IR) spectroscopy. Generally, a progressive intensity increase for bands assigned to cellulose Iß was ...

[Differentiation and characterization of yeasts pathogenic for humans (Candida albicans, Exophiala dermatitidis) and algae pathogenic for animals (Prototheca spp.) using Fourier transform infrared spectroscopy (FTIR) in comparison with conventional methods].

PubMed

Schmalreck, A F; Tränkle, P; Vanca, E; Blaschke-Hellmessen, R

1998-01-01

Due to the Fourier-Transform Infrared Spectroscopy (FT-IR) of strain specific traits demonstrated to be a suitable and efficient method for diagnostic and epidemiological determinations for the yeasts Candida albicans, Exophiala dermatitidis and the chlorophylless algae of the genus Prototheca. FT-IR leads in a rapid and economical way to reproducible results according to the spectral differences of intact cells (IR-fingerprints). Different genera, species and sub-species respectively, different strains can be recognized and grouped into different clusters and subclusters. The FT-IR analysis of Candida albicans isolates (n = 150) of 22 newborns-at-risk of an intensive care unit showed, that 86% of the children were colonised with several (2-4) different strains in the oral cavities and faeces. Stationary cross-infections could definitely be determined. Exophiala dermatitidis isolates (n = 31), mostly isolated repetitively within a period of 3 years from sputa of patients suffering from cystic fibrosis could be characterized and grouped patient-specifically over the total sampling period. Of 6 from 8 patients (75%) their individual strains remain the same and could be tracked over the three years. Cross-infections during the stationary treatment could be clearly identified by FT-IR. The Prototheca isolate (n = 43) from live-stock and farm environment showed clear distinguishable clusters differentiating the species P. wickerhamii, P. zopfii and P. stagnora. In addition, the biotypes of P. zopfii could be distinguished, especially the subclusters of variants II and III. It could be demonstrated, that FT-IR is suitable for the routine identification and differentiation of yeasts and algae. However, in spite of the gain of knowledge by using FT-IR for the characterization of microorganisms, the conventional phenotyping and/or genetic analysis of yeast or algae strains cannot be replaced completely. For a final taxonomic classification a combination of conventional methods on FT-IR together with more sophisticated molecular genetic procedures is necessary.

A Study of the Applicability of Atomic Emission Spectroscopy (AES), Fourier Transform Infrared (FT-IR) Spectroscopy, Direct Reading and Analytical Ferrography on High Performance Aircraft Engine Lubricating Oils

DTIC Science & Technology

1998-01-01

Ferrography on High Performance Aircraft Engine Lubricating Oils Allison M. Toms, Sharon 0. Hem, Tim Yarborough Joint Oil Analysis Program Technical...turbine engines by spectroscopy (AES and FT-IR) and direct reading and analytical ferrography . A statistical analysis of the data collected is...presented. Key Words: Analytical ferrography ; atomic emission spectroscopy; condition monitoring; direct reading ferrography ; Fourier transform infrared

Technical note: Characterization of lipid constitution in Fourier transform infrared spectra and spectroscopic discrimination of animal-derived feedstuffs from different species.

PubMed

Gao, F; Han, L; Yang, Z; Xu, L; Liu, X

2017-06-01

The objective of the current work was to assess the capability of Fourier transform infrared (FT-IR) spectroscopy in combination with chemometric methods to discriminate animal-derived feedstuffs from different origins based on the lipid characteristics. A total of 82 lipid samples extracted from animal-derived feedstuffs, comprising porcine, poultry, bovine, ovine, and fish samples, were investigated by gas chromatography and FT-IR. The relationship between the lipid constitutions and the responding FT-IR spectral characteristics were explored. Results indicated that high correlations ( > 0.900) were found between the contents of MUFA and PUFA and FT-IR spectral data. In addition, the peak intensity at about 1,116 and 1,098 cm-1 showed a significant difference ( < 0.05) between ruminant and nonruminant animals; the change of peak ratio (1,116:1,098) was proved consistent with the degree of unsaturation of lipid from different animal species. Successful discrimination was further achieved among porcine, poultry, bovine, and ovine meat and bone meal (MBM) and fishmeal based on lipid characteristics by applying the FT-IR spectra coupled with chemometrics, for which the values of sensitivity and specificity were close to 1 and classification error were almost equal to 0.

Evaluation of Turmeric Powder Adulterated with Metanil Yellow Using FT-Raman and FT-IR Spectroscopy

PubMed Central

Dhakal, Sagar; Chao, Kuanglin; Schmidt, Walter; Qin, Jianwei; Kim, Moon; Chan, Diane

2016-01-01

Turmeric powder (Curcuma longa L.) is valued both for its medicinal properties and for its popular culinary use, such as being a component in curry powder. Due to its high demand in international trade, turmeric powder has been subject to economically driven, hazardous chemical adulteration. This study utilized Fourier Transform-Raman (FT-Raman) and Fourier Transform-Infra Red (FT-IR) spectroscopy as separate but complementary methods for detecting metanil yellow adulteration of turmeric powder. Sample mixtures of turmeric powder and metanil yellow were prepared at concentrations of 30%, 25%, 20%, 15%, 10%, 5%, 1%, and 0.01% (w/w). FT-Raman and FT-IR spectra were acquired for these mixture samples as well as for pure samples of turmeric powder and metanil yellow. Spectral analysis showed that the FT-IR method in this study could detect the metanil yellow at the 5% concentration, while the FT-Raman method appeared to be more sensitive and could detect the metanil yellow at the 1% concentration. Relationships between metanil yellow spectral peak intensities and metanil yellow concentration were established using representative peaks at FT-Raman 1406 cm−1 and FT-IR 1140 cm−1 with correlation coefficients of 0.93 and 0.95, respectively. PMID:28231130

Fourier transform infrared spectroscopy of DNA from Borrelia burgdorferi sensu lato and Ixodes ricinus ticks

NASA Astrophysics Data System (ADS)

Muntean, Cristina M.; Stefan, Razvan; Bindea, Maria; Cozma, Vasile

2013-06-01

In this work we present a method for detection of motile and immotile Borrelia burgdorferi genomic DNA, in relation with infectious and noninfectious spirochetes. An FT-IR study of DNA isolated from B. burgdorferi sensu lato strains and from positive and negative Ixodes ricinus ticks, respectively, is reported. Motile bacterial cells from the species B. burgdorferi sensu stricto, Borrelia garinii and Borrelia afzelii were of interest. Also, FT-IR absorbance spectra of DNA from immotile spirochetes of B. burgdorferi sensu stricto, in the absence and presence of different antibiotics (doxycycline, erythromycin, gentamicin, penicillin V or phenoxymethylpenicillin, tetracycline, respectively) were investigated. FT-IR spectra, providing a high molecular structural information, have been analyzed in the wavenumber range 400-1800 cm-1. FT-IR signatures, spectroscopic band assignments and structural interpretations of these DNAs are reported. Spectral differences between FT-IR absorbances of DNAs from motile bacterial cells and immotile spirochetes, respectively, have been found. Particularly, alterations of the sugar-phosphate B-form chain in the case of DNA from Borrelia immotile cells, as compared with DNA from B. burgdorferi sensu lato motile cells have been observed. Based on this work, specific B. burgdorferi sensu lato and I. ricinus DNA-ligand interactions, respectively, might be further investigated using Fourier transform infrared spectroscopy.

Applications of QCL mid-IR imaging to the advancement of pathology

NASA Astrophysics Data System (ADS)

Sreedhar, Hari; Varma, Vishal K.; Bird, Benjamin; Guzman, Grace; Walsh, Michael J.

2017-03-01

Quantum Cascade Laser (QCL) spectroscopic imaging is a novel technique with many potential applications to histopathology. Like traditional Fourier Transform Infrared (FT-IR) imaging, QCL spectroscopic imaging derives biochemical data coupled to the spatial information of a tissue sample, and can be used to improve the diagnostic and prognostic value of assessment of a tissue biopsy. This technique also offers advantages over traditional FT-IR imaging, specifically the capacity for discrete frequency and real-time imaging. In this work we present applications of QCL spectroscopic imaging to tissue samples, including discrete frequency imaging, to compare with FT-IR and its potential value to pathology.

Detection of metanil yellow contamination in turmeric using FT-Raman and FT-IR spectroscopy

NASA Astrophysics Data System (ADS)

Dhakal, Sagar; Chao, Kuanglin; Qin, Jianwei; Kim, Moon; Schmidt, Walter; Chan, Dian

2016-05-01

Turmeric is well known for its medicinal value and is often used in Asian cuisine. Economically motivated contamination of turmeric by chemicals such as metanil yellow has been repeatedly reported. Although traditional technologies can detect such contaminants in food, high operational costs and operational complexities have limited their use to the laboratory. This study used Fourier Transform Raman Spectroscopy (FT-Raman) and Fourier Transform - Infrared Spectroscopy (FT-IR) to identify metanil yellow contamination in turmeric powder. Mixtures of metanil yellow in turmeric were prepared at concentrations of 30%, 25%, 20%, 15%, 10%, 5%, 1% and 0.01% (w/w). The FT-Raman and FT-IR spectral signal of pure turmeric powder, pure metanil yellow powder and the 8 sample mixtures were obtained and analyzed independently to identify metanil yellow contamination in turmeric. The results show that FT-Raman spectroscopy and FT-IR spectroscopy can detect metanil yellow mixed with turmeric at concentrations as low as 1% and 5%, respectively, and may be useful for non-destructive detection of adulterated turmeric powder.

Chemical fingerprinting of Arabidopsis using Fourier transform infrared (FT-IR) spectroscopic approaches.

PubMed

Gorzsás, András; Sundberg, Björn

2014-01-01

Fourier transform infrared (FT-IR) spectroscopy is a fast, sensitive, inexpensive, and nondestructive technique for chemical profiling of plant materials. In this chapter we discuss the instrumental setup, the basic principles of analysis, and the possibilities for and limitations of obtaining qualitative and semiquantitative information by FT-IR spectroscopy. We provide detailed protocols for four fully customizable techniques: (1) Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS): a sensitive and high-throughput technique for powders; (2) attenuated total reflectance (ATR) spectroscopy: a technique that requires no sample preparation and can be used for solid samples as well as for cell cultures; (3) microspectroscopy using a single element (SE) detector: a technique used for analyzing sections at low spatial resolution; and (4) microspectroscopy using a focal plane array (FPA) detector: a technique for rapid chemical profiling of plant sections at cellular resolution. Sample preparation, measurement, and data analysis steps are listed for each of the techniques to help the user collect the best quality spectra and prepare them for subsequent multivariate analysis.

Optical diagnosis of actinic cheilitis by infrared spectroscopy.

PubMed

das Chagas E Silva de Carvalho, Luis Felipe; Pereira, Thiago Martini; Magrini, Taciana Depra; Cavalcante, Ana Sueli Rodrigues; da Silva Martinho, Herculano; Almeida, Janete Dias

2016-12-01

Actinic cheilitis (AC) is considered a potentially malignant disorder of the lip. Biomolecular markers study is important to understand malignant transformation into squamous cell carcinoma. Fourier transform infra red (FT-IR) spectroscopy was used to analyze AC in this study. The aim of the study was to evaluate if FT-IR spectral regions of nucleic acids and collagen can help in early diagnosis of malignant transformation. Tissues biopsies of 14 patients diagnosed with AC and 14 normal tissues were obtained. FT-IR spectra were measured at five different points resulting in 70 spectra of each. Analysis of Principal components analysis (PCA) and linear discrimination analysis (LDA) model were also used. In order to verify the statistical difference in the spectra, Mann-Whitney U test was performed in each variable (wavenumber) with p-value <0.05. After the Mann-Whitney U test the vibrational modes of CO (Collagen 1), PO2 (Nucleic Acids) and CO asymmetric (Triglycerides/Lipids) were observed as a possible spectral biomarker. These bands were chosen because they represent the vibrational modes related to collagen and DNA, which are supposed to be changed in AC samples. Based on the PCA-LDA results, the predictive model corresponding to the area under the curve was 0.91 for the fingerprint region and 0.83 for the high wavenumber region, showing the greater accuracy of the test. FT-IR changes in collagen and nucleic acids could be used as molecular biomarkers for malignant transformation. Copyright © 2016 Elsevier B.V. All rights reserved.

Potential Second-Harmonic Ghost Bands in Fourier Transform Infrared (FT-IR) Difference Spectroscopy of Proteins.

PubMed

Ito, Shota; Kandori, Hideki; Lorenz-Fonfria, Victor A

2018-06-01

Fourier transform infrared (FT-IR) difference absorption spectroscopy is a common method for studying the structural and dynamical aspects behind protein function. In particular, the 2800-1800 cm -1 spectral range has been used to obtain information about internal (deuterated) water molecules, as well as site-specific details about cysteine residues and chemically modified and artificial amino acids. Here, we report on the presence of ghost bands in cryogenic light-induced FT-IR difference spectra of the protein bacteriorhodopsin. The presence of these ghost bands can be particularly problematic in the 2800-1900 cm -1 region, showing intensities similar to O-D vibrations from water molecules. We demonstrate that they arise from second harmonics from genuine chromophore bands located in the 1400-850 cm -1 region, generated by double-modulation artifacts caused from reflections of the IR beam at the sample and at the cryostat windows back to the interferometer (inter-reflections). The second-harmonic ghost bands can be physically removed by placing an optical filter of suitable cutoff in the beam path, but at the cost of losing part of the multiplexing advantage of FT-IR spectroscopy. We explored alternatives to the use of optical filters. Tilting the cryostat windows was effective in reducing the intensity of the second harmonic artifacts but tilting the sample windows was not, presumably by their close proximity to the focal point of the IR beam. We also introduce a simple numerical post-processing approach that can partially, but not fully, correct for second-harmonic ghost bands in FT-IR difference spectra.

Sugar and acid content of Citrus prediction modeling using FT-IR fingerprinting in combination with multivariate statistical analysis.

PubMed

Song, Seung Yeob; Lee, Young Koung; Kim, In-Jung

2016-01-01

A high-throughput screening system for Citrus lines were established with higher sugar and acid contents using Fourier transform infrared (FT-IR) spectroscopy in combination with multivariate analysis. FT-IR spectra confirmed typical spectral differences between the frequency regions of 950-1100 cm(-1), 1300-1500 cm(-1), and 1500-1700 cm(-1). Principal component analysis (PCA) and subsequent partial least square-discriminant analysis (PLS-DA) were able to discriminate five Citrus lines into three separate clusters corresponding to their taxonomic relationships. The quantitative predictive modeling of sugar and acid contents from Citrus fruits was established using partial least square regression algorithms from FT-IR spectra. The regression coefficients (R(2)) between predicted values and estimated sugar and acid content values were 0.99. These results demonstrate that by using FT-IR spectra and applying quantitative prediction modeling to Citrus sugar and acid contents, excellent Citrus lines can be early detected with greater accuracy. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparative investigation of Fourier transform infrared (FT-IR) spectroscopy and X-ray diffraction (XRD) in the determination of cotton fiber crystallinity.

PubMed

Liu, Yongliang; Thibodeaux, Devron; Gamble, Gary; Bauer, Philip; VanDerveer, Don

2012-08-01

Despite considerable efforts in developing curve-fitting protocols to evaluate the crystallinity index (CI) from X-ray diffraction (XRD) measurements, in its present state XRD can only provide a qualitative or semi-quantitative assessment of the amounts of crystalline or amorphous fraction in a sample. The greatest barrier to establishing quantitative XRD is the lack of appropriate cellulose standards, which are needed to calibrate the XRD measurements. In practice, samples with known CI are very difficult to prepare or determine. In a previous study, we reported the development of a simple algorithm for determining fiber crystallinity information from Fourier transform infrared (FT-IR) spectroscopy. Hence, in this study we not only compared the fiber crystallinity information between FT-IR and XRD measurements, by developing a simple XRD algorithm in place of a time-consuming and subjective curve-fitting process, but we also suggested a direct way of determining cotton cellulose CI by calibrating XRD with the use of CI(IR) as references.

Rapid differentiation of Listeria monocytogenes epidemic clones III and IV and their intact compared with heat-killed populations using Fourier transform infrared spectroscopy and chemometrics.

PubMed

Nyarko, Esmond B; Puzey, Kenneth A; Donnelly, Catherine W

2014-06-01

The objectives of this study were to determine if Fourier transform infrared (FT-IR) spectroscopy and multivariate statistical analysis (chemometrics) could be used to rapidly differentiate epidemic clones (ECs) of Listeria monocytogenes, as well as their intact compared with heat-killed populations. FT-IR spectra were collected from dried thin smears on infrared slides prepared from aliquots of 10 μL of each L. monocytogenes ECs (ECIII: J1-101 and R2-499; ECIV: J1-129 and J1-220), and also from intact and heat-killed cell populations of each EC strain using 250 scans at a resolution of 4 cm(-1) in the mid-infrared region in a reflectance mode. Chemometric analysis of spectra involved the application of the multivariate discriminant method for canonical variate analysis (CVA) and linear discriminant analysis (LDA). CVA of the spectra in the wavelength region 4000 to 600 cm(-1) separated the EC strains while LDA resulted in a 100% accurate classification of all spectra in the data set. Further, CVA separated intact and heat-killed cells of each EC strain and there was 100% accuracy in the classification of all spectra when LDA was applied. FT-IR spectral wavenumbers 1650 to 1390 cm(-1) were used to separate heat-killed and intact populations of L. monocytogenes. The FT-IR spectroscopy method allowed discrimination between strains that belong to the same EC. FT-IR is a highly discriminatory and reproducible method that can be used for the rapid subtyping of L. monocytogenes, as well as for the detection of live compared with dead populations of the organism. Fourier transform infrared (FT-IR) spectroscopy and multivariate statistical analysis can be used for L. monocytogenes source tracking and for clinical case isolate comparison during epidemiological investigations since the method is capable of differentiating epidemic clones and it uses a library of well-characterized strains. The FT-IR method is potentially less expensive and more rapid compared to genetic subtyping methods, and can be used for L. monocytogenes strain typing by food industries and public health agencies to enable faster response and intervention to listeriosis outbreaks. FT-IR can also be applied for routine monitoring of the pathogen in food processing plants and for investigating postprocessing contamination because it is capable of differentiating heat-killed and viable L. monocytogenes populations. © 2014 Institute of Food Technologists®

Angular acceptance analysis of an infrared focal plane array with a built-in stationary Fourier transform spectrometer.

PubMed

Gillard, Frédéric; Ferrec, Yann; Guérineau, Nicolas; Rommeluère, Sylvain; Taboury, Jean; Chavel, Pierre

2012-06-01

Stationary Fourier transform spectrometry is an interesting concept for building reliable field or embedded spectroradiometers, especially for the mid- and far- IR. Here, a very compact configuration of a cryogenic stationary Fourier transform IR (FTIR) spectrometer is investigated, where the interferometer is directly integrated in the focal plane array (FPA). We present a theoretical analysis to explain and describe the fringe formation inside the FTIR-FPA structure when illuminated by an extended source positioned at a finite distance from the detection plane. The results are then exploited to propose a simple front lens design compatible with a handheld package.

Integrated gas analyzer for complete monitoring of turbine engine test cells.

PubMed

Markham, James R; Bush, Patrick M; Bonzani, Peter J; Scire, James J; Zaccardi, Vincent A; Jalbert, Paul A; Bryant, M Denise; Gardner, Donald G

2004-01-01

Fourier transform infrared (FT-IR) spectroscopy is proving to be reliable and economical for the quantification of many gas-phase species during testing and development of gas turbine engines in ground-based facilities such as sea-level test cells and altitude test cells. FT-IR measurement applications include engine-generated exhaust gases, facility air provided as input to engines, and ambient air in and around test cells. Potentially, the traditionally used assembly of many gas-specific single gas analyzers will be eliminated. However, the quest for a single instrument capable of complete gas-phase monitoring at turbine engine test cells has previously suffered since the FT-IR method cannot measure infrared-inactive oxygen molecules, a key operational gas to both air-breathing propulsion systems and test cell personnel. To further the quest, the FT-IR sensor used for the measurements presented in this article was modified by integration of a miniature, solid-state electrochemical oxygen sensor. Embedded in the FT-IR unit at a location near the long-effective-optical-path-length gas sampling cell, the amperometric oxygen sensor provides simultaneous, complementary information to the wealth of spectroscopic data provided by the FT-IR method.

Fourier Transform Infrared Spectroscopy (FT-IR) and Simple Algorithm Analysis for Rapid and Non-Destructive Assessment of Developmental Cotton Fibers.

PubMed

Liu, Yongliang; Kim, Hee-Jin

2017-06-22

With cotton fiber growth or maturation, cellulose content in cotton fibers markedly increases. Traditional chemical methods have been developed to determine cellulose content, but it is time-consuming and labor-intensive, mostly owing to the slow hydrolysis process of fiber cellulose components. As one approach, the attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy technique has also been utilized to monitor cotton cellulose formation, by implementing various spectral interpretation strategies of both multivariate principal component analysis (PCA) and 1-, 2- or 3-band/-variable intensity or intensity ratios. The main objective of this study was to compare the correlations between cellulose content determined by chemical analysis and ATR FT-IR spectral indices acquired by the reported procedures, among developmental Texas Marker-1 (TM-1) and immature fiber ( im ) mutant cotton fibers. It was observed that the R value, CI IR , and the integrated intensity of the 895 cm -1 band exhibited strong and linear relationships with cellulose content. The results have demonstrated the suitability and utility of ATR FT-IR spectroscopy, combined with a simple algorithm analysis, in assessing cotton fiber cellulose content, maturity, and crystallinity in a manner which is rapid, routine, and non-destructive.

Understanding Why Researchers Should Use Synchrotron-Enhanced FTIR Instead of Traditional FTIR

ERIC Educational Resources Information Center

Stem, Michelle R.

2008-01-01

A synchrotron-enhanced Fourier transform infrared (SR-FTIR) specializes in combining the tremendous power, brightness, intensity, focusability, and tunability of the photons radiated by a synchrotron with FTIR ability to research the vibrational properties of the lighter elements (i.e., C, N, O, etc.). Infrared (IR) wavelengths correspond to the…

Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR FT-IR) Mapping Coupled with Multivariate Curve Resolution (MCR) for Studying the Miscibility of Chlorobutyl Rubber/Polyamide-12 Blends.

PubMed

Tang, Yongjiao; Jing, Nan; Zhang, Pudun

2015-11-01

A series of chlorobutyl rubber/polyamide-12 (CIIR/PA-12) blends compatibilized by different amounts of maleic anhydride (MAH) grafted polypropylene (PP-g-MAH) were investigated by attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR) mapping. Multivariate curve resolution (MCR) was used to process the FT-IR images. Both the spectra of pure components in the blends and their concentration distributions in a micro-region were acquired. Our results demonstrated that the blend with 15 parts per hundred rubber PP-g-MAH showed the best miscibility. An amide interphase and an imide interphase were inferred by analyzing the spectra of MCR component 3 of the blends with and without PP-g-MAH, respectively. Correspondingly, two different compatibilizing mechanisms were proposed for these blends.

Molecular structure, vibrational spectral assignments (FT-IR and FT-RAMAN), NMR, NBO, HOMO-LUMO and NLO properties of O-methoxybenzaldehyde based on DFT calculations

NASA Astrophysics Data System (ADS)

Vennila, P.; Govindaraju, M.; Venkatesh, G.; Kamal, C.

2016-05-01

Fourier transform - Infra red (FT-IR) and Fourier transform - Raman (FT-Raman) spectroscopic techniques have been carried out to analyze O-methoxy benzaldehyde (OMB) molecule. The fundamental vibrational frequencies and intensity of vibrational bands were evaluated using density functional theory (DFT). The vibrational analysis of stable isomer of OMB has been carried out by FT-IR and FT-Raman in combination with theoretical method simultaneously. The first-order hyperpolarizability and the anisotropy polarizability invariant were computed by DFT method. The atomic charges, hardness, softness, ionization potential, electronegativity, HOMO-LUMO energies, and electrophilicity index have been calculated. The 13C and 1H Nuclear magnetic resonance (NMR) have also been obtained by GIAO method. Molecular electronic potential (MEP) has been calculated by the DFT calculation method. Electronic excitation energies, oscillator strength and excited states characteristics were computed by the closed-shell singlet calculation method.

Application of attenuated total reflectance Fourier transform infrared spectroscopy for determination of cefixime in oral pharmaceutical formulations.

PubMed

Kandhro, Aftab A; Laghari, Abdul Hafeez; Mahesar, Sarfaraz A; Saleem, Rubina; Nelofar, Aisha; Khan, Salman Tariq; Sherazi, S T H

2013-11-01

A quick and reliable analytical method for the quantitative assessment of cefixime in orally administered pharmaceutical formulations is developed by using diamond cell attenuated total reflectance (ATR) Fourier transform infrared (FT-IR) spectroscopy as an easy procedure for quality control laboratories. The standards for calibration were prepared in aqueous medium ranging from 350 to 6000mg/kg. The calibration model was developed based on partial least square (PLS) using finger print region of FT-IR spectrum in the range from 1485 to 887cm(-1). Excellent coefficient of determination (R(2)) was achieved as high as 0.99976 with root mean square error of 44.8 for calibration. The application of diamond cell (smart accessory) ATR FT-IR proves a reliable determination of cefixime in pharmaceutical formulations to assess the quality of the final product. Copyright © 2013 Elsevier B.V. All rights reserved.

Wood liquefaction and its application to Novolac resin

Treesearch

Hui Pan; Chung-Yun Hse; Todd F. Shupe

2009-01-01

Wood liquefaction was conducted using phenol as a reagent solvent with a weak acid catalyst in two different reactors: (Alma et al., 1995a.) an atmospheric glass reactor and (Alma et al., 1995b.) a sealed Parr® reactor. Residues were characterized by wet chemical analyses, Fourier transform infrared (FT-IR) spectroscopy, and X-ray diffraction (XRD). The FT-IR...

Biological Applications Of Fourier Transform Infrared (FTIR) Or Bloody FTIR

NASA Astrophysics Data System (ADS)

Jakobsen, R. J.; Winters, S.; Gendreau, R. M.

1981-10-01

An ex vivo FT-IR/ATR experiment for studying blood protein adsorption at the molecular level is described. This experiment involves the use of live dogs pumping the blood through a arterial-veinal shunt to the ATR cell and back into the animal. The results from these live dog experiments are compared to results obtained using donated whole blood. These experiments demonstrate that FT-IR can be used to study aqueous, physiological, flowing solutions in real time with the sensitivity necessary to detect minor changes.

The Scope Of Fourier Transform Infrared (FTIR)

NASA Astrophysics Data System (ADS)

Hirschfeld, T.

1981-10-01

Three auarters of a century after its inception, a generation after its advantages were recognized, and a decade after its first commercialization, FT-IR dominates the growth of the IR market, and reigns alone over its high performance end. What lies ahead for FT-IR now? On one hand, the boundary between it and the classical scanning spectrometers is becoming fuzzy, as gratings attempt to use as much of FT-IR's computer technology as they can handle, and smaller FT systems invade the medium cost instrument range. On the other hand, technology advances in IR detectors, non-Fourier interference devices, and the often announced tunable laser are at long last getting set to make serious inroads in the field (although not necessarily in the manner most of us expected). However, the dominance of FT-IR as the leading edge of IR spectroscopy seems assured for a good many years. The evolution of FT-IR will be dominated by demands not yet fully satisfied such as rapid sample turnover, better quantitation, automated interpretation, higher GC-IR sensitivity, improved LC-IR, and, above all else, reliability and ease of use. These developments will be based on multiple small advances in hardware, large advances in the way systems are put together, and the traditional yearly revolutionary advances of the computer industry. The big question in the field will, however, still be whether our ambition and our skill can continue to keep up with the advances of our tools. It will be fun.

Analysis of hard-to-cook red and black common beans using Fourier transform infrared spectroscopy.

PubMed

Maurer, Giselle A; Ozen, Banu F; Mauer, Lisa J; Nielsen, S Suzanne

2004-03-24

Extracted fractions from black and red common beans (Phaseolus vulgaris) were studied using Fourier transform infrared spectroscopy (FT-IR). Beans were stored under three conditions: control at 4 degrees C; hard-to-cook (HTC) at 29 degrees C, 65% RH for 3.5 months; and refrigerated at 2 degrees C, 79% RH for 3.5 months after a HTC period (called HTC-refrigerated). Two fractions isolated from the beans, the soluble pectin fraction (SPF) and the water insoluble residue of the cell wall (WIRCW), were analyzed using diffuse reflectance (DRIFTS) FT-IR. The soaking water and cooking water from the beans were also studied using attenuated total reflectance (ATR) FT-IR. The DRIFTS FT-IR results from the SPF and WIRCW fractions were consistent with previously published data for Carioca beans showing that in general, more phenolic compounds were associated with the SPF of HTC beans than in the control beans. Results also showed that HTC-refrigerated beans had higher concentrations of phenolic compounds than control beans in the SPF. The ATR FT-IR results for soaking and cooking waters from the HTC-refrigerated and HTC beans had higher concentrations of absorbing compounds than the control beans, indicating that they lost more constituents to the water. Additionally, results indicate that the mechanism(s) for reversibility of the HTC defect could be different than the one(s) involved in the development of the defect.

Discrimination of different genuine Danshen and their extracts by Fourier transform infrared spectroscopy combined with two-dimensional correlation infrared spectroscopy

NASA Astrophysics Data System (ADS)

Liu, Xin-hu; Xu, Chang-hua; Sun, Su-qin; Huang, Jian; Zhang, Ke; Li, Guo-yu; Zhu, Yun; Zhou, Qun; Zhang, Zhi-cheng; Wang, Jin-hui

2012-11-01

In this study, six varieties of Danshen from different populations and genuine ("Daodi" in Chinese transliteration) regions were discriminated and identified by a three-step infrared spectroscopy method (Fourier transform-infrared spectroscopy (FT-IR) coupled with second derivative infrared spectroscopy (SD-IR) and two dimensional correlation infrared spectroscopy (2D-IR)). Though only small differences were found among the FT-IR spectra of the six Danshen samples, the positions and intensities of peaks at 3393, 3371, 1613, 1050, and 1036 cm-1 could be considered as the key factors to discriminate them. More significant differences were exhibited in their SD-IR, particularly for the peaks around 1080, 1144, 695, 665, 800, 1610, 1510, 1450, 1117 and 1077 cm-1. The visual 2D-IR spectra provided dynamic chemical structure information of the six Danshen samples with presenting different particular auto-peak clusters, respectively. Moreover, the contents of salvianolic acid B in all samples were measured quantitatively by a validated ultra performance liquid chromatography (UPLC), which was consistent with the FT-IR findings. This study provides a promising method for characteristics and quality control of the complicated and extremely similar herbal medicine like Danshen, which is more cost effective and time saving.

Combining FT-IR spectroscopy and multivariate analysis for qualitative and quantitative analysis of the cell wall composition changes during apples development.

PubMed

Szymanska-Chargot, M; Chylinska, M; Kruk, B; Zdunek, A

2015-01-22

The aim of this work was to quantitatively and qualitatively determine the composition of the cell wall material from apples during development by means of Fourier transform infrared (FT-IR) spectroscopy. The FT-IR region of 1500-800 cm(-1), containing characteristic bands for galacturonic acid, hemicellulose and cellulose, was examined using principal component analysis (PCA), k-means clustering and partial least squares (PLS). The samples were differentiated by development stage and cultivar using PCA and k-means clustering. PLS calibration models for galacturonic acid, hemicellulose and cellulose content from FT-IR spectra were developed and validated with the reference data. PLS models were tested using the root-mean-square errors of cross-validation for contents of galacturonic acid, hemicellulose and cellulose which was 8.30 mg/g, 4.08% and 1.74%, respectively. It was proven that FT-IR spectroscopy combined with chemometric methods has potential for fast and reliable determination of the main constituents of fruit cell walls. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparative studies on cervical and colonic malignancies using FTIR microspectroscopy

NASA Astrophysics Data System (ADS)

Mordechai, Shaul; Mark, Shlomo; Podshyvalov, A.; Kantarovich, Keren; Bernshtain, Y.; Salman, Ahmad; Erukhimovitch, Vitaly; Guterman, Hugo; Goldstein, Jed; Argov, Shmuel; Jagannathan, R.

2003-07-01

IR spectroscopy provides a new diagnostic tool due to its sensitivity to molecular composition and structure in cells, which accompany transformation from healthy to diseased state. The IR spectrum of a sample is, therefore, a biochemical fingerprint. It has been found that the most significant changes occur in the mid-IR spectral range 3-25 mm. Encouraging results have been reported in the literature on various types of cancers, such as human breast, lung, colon, cervical, and leukemia using FT-IR microspectroscopy. Much progress has also been made by several groups on IR spectral maps and IR imaging with good agreement between the data and the histopathological information. In an attempt to characterize healthy and diseased tissues, infrared microspectroscopy of cervical and colon human tissues was studied using an infrared microscopy. The comparative qualitative and quantitative changes detected using FTIR microspectroscopy are discussed.

Fourier transform infrared spectroscopy imaging of live epithelial cancer cells under non-aqueous media.

PubMed

Soh, JunYi; Chueng, Adeline; Adio, Aminat; Cooper, Alan J; Birch, Brian R; Lwaleed, Bashir A

2013-04-01

Fourier transform infrared (FT-IR) imaging is increasingly being applied to biomedical specimens, but strong IR absorption by water complicates live cell imaging. This study investigates the viability of adherent epithelial cells maintained for short periods under mineral oils in order to facilitate live cell spectroscopy using FT-IR with subsequent imaging. The MGH-U1 urothelial or CaCo2 colorectal cancer cell lines were grown on plastic surfaces or mid-range infrared transparent windows. Medium in established cultures was replaced with paraffin mineral oil, or Fluorolube, for up to 2 h, and viability assessed by supravital staining. Drug handling characteristics were also assessed. Imaging of preparations was attempted by reflectance and transmission using a Varian FT-IR microscope. Cells covered by mineral oil remained viable for 2 h, with recovery into normal medium possible. MTT ((3-(4,5-dimethylthlazol-2-yl)-2,5-diphenyl tetrazolium) conversion to crystalline formazan and differential patterns of drug uptake were maintained. The combination of a calcium fluoride substrate, Fluorolube oil, and transmission optics proved best for spectroscopy. Spectral features were used to obtain images of live cells. The viability of cells overlaid with IR transparent oils was assessed as part of a technique to optimise conditions for FT-IR imaging. Images of untreated cells were obtained using both reflectance and transmission. This represents an effective means of imaging live cells by IR spectroscopy, and also means that imaging is not necessarily a terminal event. It also increases options for producing images based on real-time biochemistry in a range of in vitro experimental and 'optical biopsy' contexts.

Chemical profiling and adulteration screening of Aquilariae Lignum Resinatum by Fourier transform infrared (FT-IR) spectroscopy and two-dimensional correlation infrared (2D-IR) spectroscopy.

PubMed

Qu, Lei; Chen, Jian-Bo; Zhang, Gui-Jun; Sun, Su-Qin; Zheng, Jing

2017-03-05

As a kind of expensive perfume and valuable herb, Aquilariae Lignum Resinatum (ALR) is often adulterated for economic motivations. In this research, Fourier transform infrared (FT-IR) spectroscopy is employed to establish a simple and quick method for the adulteration screening of ALR. First, the principal chemical constituents of ALR are characterized by FT-IR spectroscopy at room temperature and two-dimensional correlation infrared (2D-IR) spectroscopy with thermal perturbation. Besides the common cellulose and lignin compounds, a certain amount of resin is the characteristic constituent of ALR. Synchronous and asynchronous 2D-IR spectra indicate that the resin (an unstable secondary metabolite) is more sensitive than cellulose and lignin (stable structural constituents) to the thermal perturbation. Using a certified ALR sample as the reference, the infrared spectral correlation threshold is determined by 30 authentic samples and 6 adulterated samples. The spectral correlation coefficient of an authentic ALR sample to the standard reference should be not less than 0.9886 (p=0.01). Three commercial adulterated ALR samples are identified by the correlation threshold. Further interpretation of the infrared spectra of the adulterated samples indicates the common adulterating methods - counterfeiting with other kind of wood, adding ingredient such as sand to increase the weight, and adding the cheap resin such as rosin to increase the content of resin compounds. Results of this research prove that FT-IR spectroscopy can be used as a simple and accurate quality control method of ALR. Copyright © 2016 Elsevier B.V. All rights reserved.

Chemical profiling and adulteration screening of Aquilariae Lignum Resinatum by Fourier transform infrared (FT-IR) spectroscopy and two-dimensional correlation infrared (2D-IR) spectroscopy

NASA Astrophysics Data System (ADS)

Qu, Lei; Chen, Jian-bo; Zhang, Gui-Jun; Sun, Su-qin; Zheng, Jing

2017-03-01

As a kind of expensive perfume and valuable herb, Aquilariae Lignum Resinatum (ALR) is often adulterated for economic motivations. In this research, Fourier transform infrared (FT-IR) spectroscopy is employed to establish a simple and quick method for the adulteration screening of ALR. First, the principal chemical constituents of ALR are characterized by FT-IR spectroscopy at room temperature and two-dimensional correlation infrared (2D-IR) spectroscopy with thermal perturbation. Besides the common cellulose and lignin compounds, a certain amount of resin is the characteristic constituent of ALR. Synchronous and asynchronous 2D-IR spectra indicate that the resin (an unstable secondary metabolite) is more sensitive than cellulose and lignin (stable structural constituents) to the thermal perturbation. Using a certified ALR sample as the reference, the infrared spectral correlation threshold is determined by 30 authentic samples and 6 adulterated samples. The spectral correlation coefficient of an authentic ALR sample to the standard reference should be not less than 0.9886 (p = 0.01). Three commercial adulterated ALR samples are identified by the correlation threshold. Further interpretation of the infrared spectra of the adulterated samples indicates the common adulterating methods - counterfeiting with other kind of wood, adding ingredient such as sand to increase the weight, and adding the cheap resin such as rosin to increase the content of resin compounds. Results of this research prove that FT-IR spectroscopy can be used as a simple and accurate quality control method of ALR.

Characterization of southern yellow pine bark layers by Attenuated Total Reflectance (ATR) and Fourier Transform Infrared (FT-IR) Spectroscopy

Treesearch

Thomas L. Eberhardt

2009-01-01

The outer bark (rhytidome) of the southern yellow pines is a complex structure comprised of alternating layers of obliterated phloem and periderm tissues, with the latter comprised of three layers, those being phellem, phellogen, and phelloderm. An attenuated total reflectance (ATR) sampling accessory, coupled with a Fourier transform infrared (FTIR) spectrometer,...

Evaluation of Fourier transform infrared (FT-IR) spectroscopy and chemometrics as a rapid approach for sub-typing Escherichia coli O157:H7 isolates.

PubMed

Davis, R; Paoli, G; Mauer, L J

2012-09-01

The importance of tracking outbreaks of foodborne illness and the emergence of new virulent subtypes of foodborne pathogens have created the need for rapid and reliable sub-typing methods for Escherichia coli O157:H7. Fourier transform infrared (FT-IR) spectroscopy coupled with multivariate statistical analyses was used for sub-typing 30 strains of E. coli O157:H7 that had previously been typed by multilocus variable number tandem repeat analysis (MLVA) and pulsed field gel electrophoresis (PFGE). Hierarchical cluster analysis (HCA) and canonical variate analysis (CVA) of the FT-IR spectra resulted in the clustering of the same or similar MLVA types and separation of different MLVA types of E. coli O157:H7. The developed FT-IR method showed better discriminatory power than PFGE in sub-typing E. coli O157:H7. Results also indicated the spectral relatedness between different outbreak strains. However, the grouping of some strains was not in complete agreement with the clustering based on PFGE and MLVA. Additionally, HCA of the spectra differentiated the strains into 30 sub-clusters, indicating the high specificity and suitability of the method for strain level identification. Strains were also classified (97% correct) based on the type of Shiga toxin present using CVA of the spectra. This study demonstrated that FT-IR spectroscopy is suitable for rapid (≤16 h) and economical sub-typing of E. coli O157:H7 with comparable accuracy to MLVA typing. This is the first report of using an FT-IR-based method for sub-typing E. coli O157:H7. Copyright © 2012 Elsevier Ltd. All rights reserved.

Synchrotron FTIR Imaging For The Identification Of Cell Types Within Human Tissues

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

Walsh, Michael J.; Pounder, F. Nell; Nasse, Michael J.

2010-02-03

The use of synchrotron Fourier Transform Infrared spectroscopy (S-FTIR) has been shown to be a very promising tool for biomedical research. S-FTIR spectroscopy allows for the fast acquisition of infrared (IR) spectra at a spatial resolution approaching the IR diffraction limit. The development of the Infrared Environmental Imaging (IRENI) beamline at the Synchrotron Radiation Center (SRC) at the University of Wisconsin-Madison has allowed for diffraction limited imaging measurements of cells in human prostate and breast tissues. This has allowed for the identification of cell types within tissues that would otherwise not have been resolvable using conventional FTIR sources.

Rapid and quantitative detection of the microbial spoilage of meat by fourier transform infrared spectroscopy and machine learning.

PubMed

Ellis, David I; Broadhurst, David; Kell, Douglas B; Rowland, Jem J; Goodacre, Royston

2002-06-01

Fourier transform infrared (FT-IR) spectroscopy is a rapid, noninvasive technique with considerable potential for application in the food and related industries. We show here that this technique can be used directly on the surface of food to produce biochemically interpretable "fingerprints." Spoilage in meat is the result of decomposition and the formation of metabolites caused by the growth and enzymatic activity of microorganisms. FT-IR was exploited to measure biochemical changes within the meat substrate, enhancing and accelerating the detection of microbial spoilage. Chicken breasts were purchased from a national retailer, comminuted for 10 s, and left to spoil at room temperature for 24 h. Every hour, FT-IR measurements were taken directly from the meat surface using attenuated total reflectance, and the total viable counts were obtained by classical plating methods. Quantitative interpretation of FT-IR spectra was possible using partial least-squares regression and allowed accurate estimates of bacterial loads to be calculated directly from the meat surface in 60 s. Genetic programming was used to derive rules showing that at levels of 10(7) bacteria.g(-1) the main biochemical indicator of spoilage was the onset of proteolysis. Thus, using FT-IR we were able to acquire a metabolic snapshot and quantify, noninvasively, the microbial loads of food samples accurately and rapidly in 60 s, directly from the sample surface. We believe this approach will aid in the Hazard Analysis Critical Control Point process for the assessment of the microbiological safety of food at the production, processing, manufacturing, packaging, and storage levels.

Validation of ATR FT-IR to identify polymers of plastic marine debris, including those ingested by marine organisms.

PubMed

Jung, Melissa R; Horgen, F David; Orski, Sara V; Rodriguez C, Viviana; Beers, Kathryn L; Balazs, George H; Jones, T Todd; Work, Thierry M; Brignac, Kayla C; Royer, Sarah-Jeanne; Hyrenbach, K David; Jensen, Brenda A; Lynch, Jennifer M

2018-02-01

Polymer identification of plastic marine debris can help identify its sources, degradation, and fate. We optimized and validated a fast, simple, and accessible technique, attenuated total reflectance Fourier transform infrared spectroscopy (ATR FT-IR), to identify polymers contained in plastic ingested by sea turtles. Spectra of consumer good items with known resin identification codes #1-6 and several #7 plastics were compared to standard and raw manufactured polymers. High temperature size exclusion chromatography measurements confirmed ATR FT-IR could differentiate these polymers. High-density (HDPE) and low-density polyethylene (LDPE) discrimination is challenging but a clear step-by-step guide is provided that identified 78% of ingested PE samples. The optimal cleaning methods consisted of wiping ingested pieces with water or cutting. Of 828 ingested plastics pieces from 50 Pacific sea turtles, 96% were identified by ATR FT-IR as HDPE, LDPE, unknown PE, polypropylene (PP), PE and PP mixtures, polystyrene, polyvinyl chloride, and nylon. Published by Elsevier Ltd.

Honey bee odorant-binding protein 14: effects on thermal stability upon odorant binding revealed by FT-IR spectroscopy and CD measurements.

PubMed

Schwaighofer, Andreas; Kotlowski, Caroline; Araman, Can; Chu, Nam; Mastrogiacomo, Rosa; Becker, Christian; Pelosi, Paolo; Knoll, Wolfgang; Larisika, Melanie; Nowak, Christoph

2014-03-01

In the present work, we study the effect of odorant binding on the thermal stability of honey bee (Apis mellifera L.) odorant-binding protein 14. Thermal denaturation of the protein in the absence and presence of different odorant molecules was monitored by Fourier transform infrared spectroscopy (FT-IR) and circular dichroism (CD). FT-IR spectra show characteristic bands for intermolecular aggregation through the formation of intermolecular β-sheets during the heating process. Transition temperatures in the FT-IR spectra were evaluated using moving-window 2D correlation maps and confirmed by CD measurements. The obtained results reveal an increase of the denaturation temperature of the protein when bound to an odorant molecule. We could also discriminate between high- and low-affinity odorants by determining transition temperatures, as demonstrated independently by the two applied methodologies. The increased thermal stability in the presence of ligands is attributed to a stabilizing effect of non-covalent interactions between odorant-binding protein 14 and the odorant molecule.

Electron paramagnetic resonance and FT-IR spectroscopic studies of glycine anhydride and betaine hydrochloride

NASA Astrophysics Data System (ADS)

Halim Başkan, M.; Kartal, Zeki; Aydın, Murat

2015-12-01

Gamma irradiated powders of glycine anhydride and betaine hydrochloride have been investigated at room temperature by electron paramagnetic resonance (EPR). In these compounds, the observed paramagnetic species were attributed to the R1 and R2 radicals, respectively. It was determined that the free electron interacted with environmental protons and 14N nucleus in both radicals. The EPR spectra of gamma irradiated powder samples remained unchanged at room temperature for two weeks after irradiation. Also, the Fourier Transform Infrared (FT-IR), FT-Raman and thermal analyses of both compounds were investigated. The functional groups in the molecular structures of glycine anhydride and betaine hydrochloride were identified by vibrational spectroscopies (FT-IR and FT-Raman).

Fourier transform infrared spectroscopy as a metabolite fingerprinting tool for monitoring the phenotypic changes in complex bacterial communities capable of degrading phenol.

PubMed

Wharfe, Emma S; Jarvis, Roger M; Winder, Catherine L; Whiteley, Andrew S; Goodacre, Royston

2010-12-01

The coking process produces great volumes of wastewater contaminated with pollutants such as cyanides, sulfides and phenolics. Chemical and physical remediation of this wastewater removes the majority of these pollutants; however, these processes do not remove phenol and thiocyanate. The removal of these compounds has been effected during bioremediation with activated sludge containing a complex microbial community. In this investigation we acquired activated sludge from an industrial bioreactor capable of degrading phenol. The sludge was incubated in our laboratory and monitored for its ability to degrade phenol over a 48 h period. Multiple samples were taken across the time-course and analysed by Fourier transform infrared (FT-IR) spectroscopy. FT-IR was used as a whole-organism fingerprinting approach to monitor biochemical changes in the bacterial cells during the degradation of phenol. We also investigated the ability of the activated sludge to degrade phenol following extended periods (2-131 days) of storage in the absence of phenol. A reduction was observed in the ability of the microbial community to degrade phenol and this was accompanied by a detectable biochemical change in the FT-IR fingerprint related to cellular phenotype of the microbial community. In the absence of phenol a decrease in thiocyanate vibrations was observed, reflecting the ability of these communities to degrade this substrate. Actively degrading communities showed an additional new band in their FT-IR spectra that could be attributed to phenol degradation products from the ortho- and meta-cleavage of the aromatic ring. This study demonstrates that FT-IR spectroscopy when combined with chemometric analysis is a very powerful high throughput screening approach for assessing the metabolic capability of complex microbial communities. © 2010 Society for Applied Microbiology and Blackwell Publishing Ltd.

Fourier transform-infrared spectroscopic methods for microbial ecology: analysis of bacteria, bacteria-polymer mixtures and biofilms

NASA Technical Reports Server (NTRS)

Nichols, P. D.; Henson, J. M.; Guckert, J. B.; Nivens, D. E.; White, D. C.

1985-01-01

Fourier transform-infrared (FT-IR) spectroscopy has been used to rapidly and nondestructively analyze bacteria, bacteria-polymer mixtures, digester samples and microbial biofilms. Diffuse reflectance FT-IR (DRIFT) analysis of freeze-dried, powdered samples offered a means of obtaining structural information. The bacteria examined were divided into two groups. The first group was characterized by a dominant amide I band and the second group of organisms displayed an additional strong carbonyl stretch at approximately 1740 cm-1. The differences illustrated by the subtraction spectra obtained for microbes of the two groups suggest that FT-IR spectroscopy can be utilized to recognize differences in microbial community structure. Calculation of specific band ratios has enabled the composition of bacteria and extracellular or intracellular storage product polymer mixtures to be determined for bacteria-gum arabic (amide I/carbohydrate C-O approximately 1150 cm-1) and bacteria-poly-beta-hydroxybutyrate (amide I/carbonyl approximately 1740 cm-1). The key band ratios correlate with the compositions of the material and provide useful information for the application of FT-IR spectroscopy to environmental biofilm samples and for distinguishing bacteria grown under differing nutrient conditions. DRIFT spectra have been obtained for biofilms produced by Vibrio natriegens on stainless steel disks. Between 48 and 144 h, an increase in bands at approximately 1440 and 1090 cm-1 was seen in FT-IR spectra of the V. natriegens biofilm. DRIFT spectra of mixed culture effluents of anaerobic digesters show differences induced by shifts in input feedstocks. The use of flow-through attenuated total reflectance has permitted in situ real-time changes in biofilm formation to be monitored and provides a powerful tool for understanding the interactions within adherent microbial consortia.

Application of Fourier transform infrared spectroscopy and chemometrics for differentiation of Salmonella enterica serovar Enteritidis phage types.

PubMed

Preisner, Ornella; Guiomar, Raquel; Machado, Jorge; Menezes, José Cardoso; Lopes, João Almeida

2010-06-01

Fourier transform infrared (FT-IR) spectroscopy and chemometric techniques were used to discriminate five closely related Salmonella enterica serotype Enteritidis phage types, phage type 1 (PT1), PT1b, PT4b, PT6, and PT6a. Intact cells and outer membrane protein (OMP) extracts from bacterial cell membranes were subjected to FT-IR analysis in transmittance mode. Spectra were collected over a wavenumber range from 4,000 to 600 cm(-1). Partial least-squares discriminant analysis (PLS-DA) was used to develop calibration models based on preprocessed FT-IR spectra. The analysis based on OMP extracts provided greater separation between the Salmonella Enteritidis PT1-PT1b, PT4b, and PT6-PT6a groups than the intact cell analysis. When these three phage type groups were considered, the method based on OMP extract FT-IR spectra was 100% accurate. Moreover, complementary local models that considered only the PT1-PT1b and PT6-PT6a groups were developed, and the level of discrimination increased. PT1 and PT1b isolates were differentiated successfully with the local model using the entire OMP extract spectrum (98.3% correct predictions), whereas the accuracy of discrimination between PT6 and PT6a isolates was 86.0%. Isolates belonging to different phage types (PT19, PT20, and PT21) were used with the model to test its robustness. For the first time it was demonstrated that FT-IR analysis of OMP extracts can be used for construction of robust models that allow fast and accurate discrimination of different Salmonella Enteritidis phage types.

Application of Diffuse Reflectance FT-IR Spectroscopy for the Surface Study of Kevlar Fibers

NASA Astrophysics Data System (ADS)

Chatzi, E. G.; Ishida, H.; Koenig, J. L.

1985-12-01

The surfaces of Kevlar-49 aramid fibers, being used in high-performance composite materials, have been characterized by diffuse reflectance Fourier transform infrared (FT-IR) spectroscopy. Enhancement of the surface selectivity of the technique has been achieved using KBr overlayers. The water absorbed by both the skin and the core of the fibers has been characterized by using this technique and the accessibility of the fiber functional groups has been evaluated.

Fourier transform infrared spectroscopy for analysis of kidney stones.

PubMed

Khan, Aysha Habib; Imran, Sheharbano; Talati, Jamsheer; Jafri, Lena

2018-01-01

To compare the results of a chemical method of kidney stone analysis with the results of Fourier transform infrared (FT-IR) spectroscopy. Kidney stones collected between June and October 2015 were simultaneously analyzed by chemical and FT-IR methods. Kidney stones (n=449) were collected from patients from 1 to 81 years old. Most stones were from adults, with only 11.5% from children (aged 3-16 years) and 1.5% from children aged <2 years. The male to female ratio was 4.6. In adults, the calcium oxalate stone type, calcium oxalate monohydrate (COM, n=224), was the most common crystal, followed by uric acid and calcium oxalate dihydrate (COD, n=83). In children, the most frequently occurring type was predominantly COD (n=21), followed by COM (n=11), ammonium urate (n=10), carbonate apatite (n=6), uric acid (n=4), and cystine (n=1). Core composition in 22 stones showed ammonium urate (n=2), COM (n=2), and carbonate apatite (n=1) in five stones, while uric acid crystals were detected (n=13) by FT-IR. While chemical analysis identified 3 stones as uric acid and the rest as calcium oxalate only. Agreement between the two methods was moderate, with a kappa statistic of 0.57 (95% confidence interval, 0.5-0.64). Disagreement was noted in the analysis of 77 stones. FT-IR analysis of kidney stones can overcome many limitations associated with chemical analysis.

Discrimination of cultivation ages and cultivars of ginseng leaves using Fourier transform infrared spectroscopy combined with multivariate analysis

PubMed Central

Kwon, Yong-Kook; Ahn, Myung Suk; Park, Jong Suk; Liu, Jang Ryol; In, Dong Su; Min, Byung Whan; Kim, Suk Weon

2013-01-01

To determine whether Fourier transform (FT)-IR spectral analysis combined with multivariate analysis of whole-cell extracts from ginseng leaves can be applied as a high-throughput discrimination system of cultivation ages and cultivars, a total of total 480 leaf samples belonging to 12 categories corresponding to four different cultivars (Yunpung, Kumpung, Chunpung, and an open-pollinated variety) and three different cultivation ages (1 yr, 2 yr, and 3 yr) were subjected to FT-IR. The spectral data were analyzed by principal component analysis and partial least squares-discriminant analysis. A dendrogram based on hierarchical clustering analysis of the FT-IR spectral data on ginseng leaves showed that leaf samples were initially segregated into three groups in a cultivation age-dependent manner. Then, within the same cultivation age group, leaf samples were clustered into four subgroups in a cultivar-dependent manner. The overall prediction accuracy for discrimination of cultivars and cultivation ages was 94.8% in a cross-validation test. These results clearly show that the FT-IR spectra combined with multivariate analysis from ginseng leaves can be applied as an alternative tool for discriminating of ginseng cultivars and cultivation ages. Therefore, we suggest that this result could be used as a rapid and reliable F1 hybrid seed-screening tool for accelerating the conventional breeding of ginseng. PMID:24558311

Kinetics of lisinopril intramolecular cyclization in solid phase monitored by Fourier transform infrared microscopy.

PubMed

Widjaja, Effendi; Tan, Wei Jian

2008-08-01

The solid-state intramolecular cyclization of lisinopril to diketopiperazine was investigated by in situ Fourier transform infrared (FT-IR) microscopy. Using a controllable heating cell, the isothermal transformation was monitored in situ at 147.5, 150, 152.5, 155, and 157.5 degrees C. The collected time-dependent FT-IR spectra at each isothermal temperature were preprocessed and analyzed using a multivariate chemometric approach. The pure component spectra of the observable component (lisinopril and diketopiperazine) were resolved and their time-dependent relative contributions were also determined. Model-free and various model fitting methods were implemented in the kinetic analysis to estimate the activation energy of the intramolecular cyclization reaction. Arrhenius plots indicate that the activation energy is circa 327 kJ/mol.

HazMatID (trademark) Replacement Project

DTIC Science & Technology

2013-05-09

replacement for the Smiths Detection HazMatIDTM on the 886H allowance standard, a search of Fourier transform infrared spectroscopy ( FTIR ) instruments was...uses FTIR spectroscopy. It has the capability to identify chemical warfare agents, explosives , toxic industrial chemicals, narcotics, and...uses FTIR technology , providing a wider spectral coverage and higher spectral resolution. Findings: As I operated the Mobile-IR, I found it to

Volatility-dependent 2D IR correlation analysis of traditional Chinese medicine ‘Red Flower Oil’ preparation from different manufacturers

NASA Astrophysics Data System (ADS)

Wu, Yan-Wen; Sun, Su-Qin; Zhou, Qun; Tao, Jia-Xun; Noda, Isao

2008-06-01

As a traditional Chinese medicine (TCM), 'Red Flower Oil' preparation is widely used as a household remedy in China and Southeast Asia. Usually, the preparation is a mixture of several plant essential oils with different volatile features, such as wintergreen oil, turpentine oil and clove oil. The proportions of these plant essential oils in 'Red Flower Oil' vary from different manufacturers. Thus, it is important to develop a simple and rapid evaluation method for quality assurance of the preparations. Fourier transform infrared (FT-IR) was applied and two-dimensional correlation infrared spectroscopy (2D IR) based on the volatile characteristic of samples was used to enhance the resolution of FT-IR spectra. 2D IR technique could, not only easily provide the composition and their volatile sequences in 'Red flower Oil' preparations, but also rapidly discriminate the subtle differences in products from different manufacturers. Therefore, FT-IR combined with volatility-dependent 2D IR correlation analysis provides a very fast and effective method for the quality control of essential oil mixtures in TCM.

Rapid and quantitative detection of the microbial spoilage in milk using Fourier transform infrared spectroscopy and chemometrics.

PubMed

Nicolaou, Nicoletta; Goodacre, Royston

2008-10-01

Microbiological safety plays a very significant part in the quality control of milk and dairy products worldwide. Current methods used in the detection and enumeration of spoilage bacteria in pasteurized milk in the dairy industry, although accurate and sensitive, are time-consuming. FT-IR spectroscopy is a metabolic fingerprinting technique that can potentially be used to deliver results with the same accuracy and sensitivity, within minutes after minimal sample preparation. We tested this hypothesis using attenuated total reflectance (ATR), and high throughput (HT) FT-IR techniques. Three main types of pasteurized milk - whole, semi-skimmed and skimmed - were used and milk was allowed to spoil naturally by incubation at 15 degrees C. Samples for FT-IR were obtained at frequent, fixed time intervals and pH and total viable counts were also recorded. Multivariate statistical methods, including principal components-discriminant function analysis and partial least squares regression (PLSR), were then used to investigate the relationship between metabolic fingerprints and the total viable counts. FT-IR ATR data for all milks showed reasonable results for bacterial loads above 10(5) cfu ml(-1). By contrast, FT-IR HT provided more accurate results for lower viable bacterial counts down to 10(3) cfu ml(-1) for whole milk and, 4 x 10(2) cfu ml(-1) for semi-skimmed and skimmed milk. Using FT-IR with PLSR we were able to acquire a metabolic fingerprint rapidly and quantify the microbial load of milk samples accurately, with very little sample preparation. We believe that metabolic fingerprinting using FT-IR has very good potential for future use in the dairy industry as a rapid method of detection and enumeration.

Carbohydrate and lipid spectroscopic molecular structures of different alfalfa hay and their relationship with nutrient availability in ruminants

PubMed Central

Yari, Mojtaba; Valizadeh, Reza; Nnaserian, Abbas Ali; Jonker, Arjan; Yu, Peiqiang

2017-01-01

Objective This study was conducted to determine molecular structures related to carbohydrates and lipid in alfalfa hay cut at early bud, late bud and early flower and in the afternoon and next morning using Fourier transform infrared spectroscopy (FT/IR) and to determine their relationship with alfalfa hay nutrient profile and availability in ruminants. Methods Chemical composition analysis, carbohydrate fractionation, in situ ruminal degradability, and DVE/OEB model were used to measure nutrient profile and availability of alfalfa hay. Univariate analysis, hierarchical cluster analysis (CLA) and principal components analysis (PCA) were conducted to identify FT/IR spectra differences. Results The FT/IR non-structural carbohydrate (NSCHO) to total carbohydrates and NSCHO to structural carbohydrate ratios decreased (p<0.05), while lignin to NSCHO and lipid CH3 symmetric to CH2 symmetric ratios increased with advancing maturity (p<0.05). The FT/IR spectra related to structural carbohydrates, lignin and lipids were distinguished for alfalfa hay at three maturities by PCA and CLA, while FT/IR molecular structures related to carbohydrates and lipids were similar between alfalfa hay cut in the morning and afternoon when analyzed by PCA and CLA analysis. Positive correlations were found for FT/IR NSCHO to total carbohydrate and NSCHO to structural carbohydrate ratios with non-fiber carbohydrate (by wet chemistry), ruminal fast and intermediately degradable carbohydrate fractions and total ruminal degradability of carbohydrates and predicted intestinal nutrient availability in dairy cows (r≥0.60; p<0.05) whereas FT/IR lignin to NSCHO and CH3 to CH2 symmetric stretching ratio had negative correlation with predicted ruminal and intestinal nutrient availability of alfalfa hay in dairy cows (r≥−0.60; p<0.05). Conclusion FT/IR carbohydrate and lipid molecular structures in alfalfa hay changed with advancing maturity from early bud to early flower, but not during the day, and these molecular structures correlated with predicted nutrient supply of alfalfa hay in ruminants. PMID:28335093

Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Spectroscopy as an Analytical Method to Investigate the Secondary Structure of a Model Protein Embedded in Solid Lipid Matrices.

PubMed

Zeeshan, Farrukh; Tabbassum, Misbah; Jorgensen, Lene; Medlicott, Natalie J

2018-02-01

Protein drugs may encounter conformational perturbations during the formulation processing of lipid-based solid dosage forms. In aqueous protein solutions, attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy can investigate these conformational changes following the subtraction of spectral interference of solvent with protein amide I bands. However, in solid dosage forms, the possible spectral contribution of lipid carriers to protein amide I band may be an obstacle to determine conformational alterations. The objective of this study was to develop an ATR FT-IR spectroscopic method for the analysis of protein secondary structure embedded in solid lipid matrices. Bovine serum albumin (BSA) was chosen as a model protein, while Precirol AT05 (glycerol palmitostearate, melting point 58 ℃) was employed as the model lipid matrix. Bovine serum albumin was incorporated into lipid using physical mixing, melting and mixing, or wet granulation mixing methods. Attenuated total reflection FT-IR spectroscopy and size exclusion chromatography (SEC) were performed for the analysis of BSA secondary structure and its dissolution in aqueous media, respectively. The results showed significant interference of Precirol ATO5 with BSA amide I band which was subtracted up to 90% w/w lipid content to analyze BSA secondary structure. In addition, ATR FT-IR spectroscopy also detected thermally denatured BSA solid alone and in the presence of lipid matrix indicating its suitability for the detection of denatured protein solids in lipid matrices. Despite being in the solid state, conformational changes occurred to BSA upon incorporation into solid lipid matrices. However, the extent of these conformational alterations was found to be dependent on the mixing method employed as indicated by area overlap calculations. For instance, the melting and mixing method imparted negligible effect on BSA secondary structure, whereas the wet granulation mixing method promoted more changes. Size exclusion chromatography analysis depicted the complete dissolution of BSA in the aqueous media employed in the wet granulation method. In conclusion, an ATR FT-IR spectroscopic method was successfully developed to investigate BSA secondary structure in solid lipid matrices following the subtraction of lipid spectral interference. The ATR FT-IR spectroscopy could further be applied to investigate the secondary structure perturbations of therapeutic proteins during their formulation development.

Differentiation of the root of Cultivated Ginseng, Mountain Cultivated Ginseng and Mountain Wild Ginseng using FT-IR and two-dimensional correlation IR spectroscopy

NASA Astrophysics Data System (ADS)

Liu, Dan; Li, Yong-Guo; Xu, Hong; Sun, Su-Qin; Wang, Zheng-Tao

2008-07-01

Ginseng is one of the most widely used herbal medicines. Based on the grown environments and the cultivate method, three kinds of ginseng, Cultivated Ginseng (CG), Mountain Cultivated Ginseng (MCG) and Mountain Wild Ginseng (MWG) are classified. A novel and scientific-oriented method was developed and established to discriminate and identify three kinds of ginseng using Fourier transform infrared spectroscopy (FT-IR), secondary derivative IR spectra and two-dimensional correlation infrared spectroscopy (2D-IR). The findings indicated that the relative contents of starch in the CG were more than that in MCG and MWG, while the relative contents of calcium oxalate and lipids in MWG were more than that in CG and MCG, and the relative contents of fatty acid in MCG were more than that in CG and MWG. The hierarchical cluster analysis was applied to data analysis of MWG, CG and MWG, which could be classified successfully. The results demonstrated the macroscopic IR fingerprint method, including FT-IR, secondary derivative IR and 2D-IR, can be applied to discriminate different ginsengs rapidly, effectively and non-destructively.

Analysis of Chuanxiong Rhizoma and its active components by Fourier transform infrared spectroscopy combined with two-dimensional correlation infrared spectroscopy.

PubMed

Guo, Yizhen; Lv, Beiran; Wang, Jingjuan; Liu, Yang; Sun, Suqin; Xiao, Yao; Lu, Lina; Xiang, Li; Yang, Yanfang; Qu, Lei; Meng, Qinghong

2016-01-15

As complicated mixture systems, active components of Chuanxiong Rhizoma are very difficult to identify and discriminate. In this paper, the macroscopic IR fingerprint method including Fourier transform infrared spectroscopy (FT-IR), the second derivative infrared spectroscopy (SD-IR) and two-dimensional correlation infrared spectroscopy (2DCOS-IR), was applied to study and identify Chuanxiong raw materials and its different segmented production of HPD-100 macroporous resin. Chuanxiong Rhizoma is rich in sucrose. In the FT-IR spectra, water eluate is more similar to sucrose than the powder and the decoction. Their second derivative spectra amplified the differences and revealed the potentially characteristic IR absorption bands and combined with the correlation coefficient, concluding that 50% ethanol eluate had more ligustilide than other eluates. Finally, it can be found from 2DCOS-IR spectra that proteins were extracted by ethanol from Chuanxiong decoction by HPD-100 macroporous resin. It was demonstrated that the above three-step infrared spectroscopy could be applicable for quick, non-destructive and effective analysis and identification of very complicated and similar mixture systems of traditional Chinese medicines. Copyright © 2015 Elsevier B.V. All rights reserved.

Distinguishing ovarian maturity of farmed white sturgeon (Acipenser transmontanus) by Fourier transform infrared spectroscopy: a potential tool for caviar production management.

PubMed

Lu, Xiaonan; Webb, Molly; Talbott, Mariah; Van Eenennaam, Joel; Palumbo, Amanda; Linares-Casenave, Javier; Doroshov, Serge; Struffenegger, Peter; Rasco, Barbara

2010-04-14

Fourier transform infrared spectroscopy (FT-IR, 4000-400 cm(-1)) was applied to blood plasma of farmed white sturgeon (N = 40) to differentiate and predict the stages of ovarian maturity. Spectral features of sex steroids (approximately 3000 cm(-1)) and vitellogenin (approximately 1080 cm(-1)) were identified. Clear segregation of maturity stages (previtellogenesis, vitellogenesis, postvitellogenesis, and follicular atresia) was achieved using principal component analysis (PCA). Progression of oocyte development in the late phase of vitellogenesis was also monitored using PCA based on changes in plasma concentrations of sex steroid and lipid content. The observed oocyte polarization index (PI, a measure of nuclear migration) was correlated with changes in plasma sex steroid levels revealed by FT-IR PCA results. A partial least squares (PLS) model predicted PI values within the range 0.12-0.40 (R = 0.95, SEP = 2.18%) from differences in spectral features. These results suggest that FT-IR may be a good tool for assessing ovarian maturity in farmed sturgeon and will reduce the need for the invasive ovarian biopsy required for PI determination.

Rapid detection of talcum powder in tea using FT-IR spectroscopy coupled with chemometrics

PubMed Central

Li, Xiaoli; Zhang, Yuying; He, Yong

2016-01-01

This paper investigated the feasibility of Fourier transform infrared transmission (FT-IR) spectroscopy to detect talcum powder illegally added in tea based on chemometric methods. Firstly, 210 samples of tea powder with 13 dose levels of talcum powder were prepared for FT-IR spectra acquirement. In order to highlight the slight variations in FT-IR spectra, smoothing, normalize and standard normal variate (SNV) were employed to preprocess the raw spectra. Among them, SNV preprocessing had the best performance with high correlation of prediction (RP = 0.948) and low root mean square error of prediction (RMSEP = 0.108) of partial least squares (PLS) model. Then 18 characteristic wavenumbers were selected based on a hybrid of backward interval partial least squares (biPLS) regression, competitive adaptive reweighted sampling (CARS) algorithm and successive projections algorithm (SPA). These characteristic wavenumbers only accounted for 0.64% of the full wavenumbers. Following that, 18 characteristic wavenumbers were used to build linear and nonlinear determination models by PLS regression and extreme learning machine (ELM), respectively. The optimal model with RP = 0.963 and RMSEP = 0.137 was achieved by ELM algorithm. These results demonstrated that FT-IR spectroscopy with chemometrics could be used successfully to detect talcum powder in tea. PMID:27468701

Structural analysis of the industrial grade calcite

NASA Astrophysics Data System (ADS)

Shah, Rajiv P.; Raval, Kamlesh G.

2017-05-01

The chemical, optical and structural characterization of the industrial grade Calcite by EDAX, FT-IR and XRD. EDAX is a widely used technique to analyze the chemical components in a material, FT-IR stands for Fourier Transform Infra-Red, the preferred method of infrared spectroscopy. The resultant spectrum represents the molecular absorption and transmission, creating a molecular fingerprint of the sample, The atomic planes of a crystal cause an incident beam of X-rays to interfere with one another as they leave the crystal. The phenomenon is called X ray diffraction.(XRD). Data analysis of EDAX, FT-IR and XRD has been carried out with help of various instruments and software and find out the results of the these industrial grade materials which are mostly used in ceramics industries

Attenuated total reflectance-FT-IR spectroscopy for gunshot residue analysis: potential for ammunition determination.

PubMed

Bueno, Justin; Sikirzhytski, Vitali; Lednev, Igor K

2013-08-06

The ability to link a suspect to a particular shooting incident is a principal task for many forensic investigators. Here, we attempt to achieve this goal by analysis of gunshot residue (GSR) through the use of attenuated total reflectance (ATR) Fourier transform infrared spectroscopy (FT-IR) combined with statistical analysis. The firearm discharge process is analogous to a complex chemical process. Therefore, the products of this process (GSR) will vary based upon numerous factors, including the specific combination of the firearm and ammunition which was discharged. Differentiation of FT-IR data, collected from GSR particles originating from three different firearm-ammunition combinations (0.38 in., 0.40 in., and 9 mm calibers), was achieved using projection to latent structures discriminant analysis (PLS-DA). The technique was cross (leave-one-out), both internally and externally, validated. External validation was achieved via assignment (caliber identification) of unknown FT-IR spectra from unknown GSR particles. The results demonstrate great potential for ATR-FT-IR spectroscopic analysis of GSR for forensic purposes.

Differentiation of Body Fluid Stains on Fabrics Using External Reflection Fourier Transform Infrared Spectroscopy (FT-IR) and Chemometrics.

PubMed

Zapata, Félix; de la Ossa, Ma Ángeles Fernández; García-Ruiz, Carmen

2016-04-01

Body fluids are evidence of great forensic interest due to the DNA extracted from them, which allows genetic identification of people. This study focuses on the discrimination among semen, vaginal fluid, and urine stains (main fluids in sexual crimes) placed on different colored cotton fabrics by external reflection Fourier transform infrared spectroscopy (FT-IR) combined with chemometrics. Semen-vaginal fluid mixtures and potential false positive substances commonly found in daily life such as soaps, milk, juices, and lotions were also studied. Results demonstrated that the IR spectral signature obtained for each body fluid allowed its identification and the correct classification of unknown stains by means of principal component analysis (PCA) and soft independent modeling of class analogy (SIMCA). Interestingly, results proved that these IR spectra did not show any bands due to the color of the fabric and no substance of those present in daily life which were analyzed, provided a false positive. © The Author(s) 2016.

Remote skin tissue diagnostics in vivo by fiber optic evanescent wave Fourier transform infrared (FEW-FTIR) spectroscopy

NASA Astrophysics Data System (ADS)

Afanasyeva, Natalia I.; Kolyakov, Sergei F.; Butvina, Leonid N.

1998-04-01

The new method of fiber-optical evanescent wave Fourier transform IR (FEW-FTIR) spectroscopy has been applied to the diagnostics of normal tissue, as well as precancerous and cancerous conditions. The FEW-FTIR technique is nondestructive and sensitive to changes of vibrational spectra in the IR region, without heating and damaging human and animal skin tissue. Therefore this method and technique is an ideal diagnostic tool for tumor and cancer characterization at an early stage of development on a molecular level. The application of fiber optic technology in the middle IR region is relatively inexpensive and can be adapted easily to any commercially available tabletop FTIR spectrometers. This method of diagnostics is fast, remote, and can be applied to many fields Noninvasive medical diagnostics of skin cancer and other skin diseases in vivo, ex vivo, and in vitro allow for the development convenient, remote clinical applications in dermatology and related fields. The spectral variations from normal to pathological skin tissue and environmental influence on skin have been measured and assigned in the regions of 850-4000 cm-1. The lipid structure changes are discussed. We are able to develop the spectral histopathology as a fast and informative tool of analysis.

Beyond Fourier Transform Infrared Spectroscopy: External Cavity Quantum Cascade Laser-Based Mid-infrared Transmission Spectroscopy of Proteins in the Amide I and Amide II Region.

PubMed

Schwaighofer, Andreas; Montemurro, Milagros; Freitag, Stephan; Kristament, Christian; Culzoni, María J; Lendl, Bernhard

2018-05-24

In this work, we present a setup for mid-IR measurements of the protein amide I and amide II bands in aqueous solution. Employing a latest generation external cavity-quantum cascade laser (EC-QCL) at room temperature in pulsed operation mode allowed implementing a high optical path length of 31 μm that ensures robust sample handling. By application of a data processing routine, which removes occasionally deviating EC-QCL scans, the noise level could be lowered by a factor of 4. The thereby accomplished signal-to-noise ratio is better by a factor of approximately 2 compared to research-grade Fourier transform infrared (FT-IR) spectrometers at equal acquisition times. Employing this setup, characteristic spectral features of three representative proteins with different secondary structures could be measured at concentrations as low as 1 mg mL -1 . Mathematical evaluation of the spectral overlap confirms excellent agreement of the quantum cascade laser infrared spectroscropy (QCL-IR) transmission measurements with protein spectra acquired by FT-IR spectroscopy. The presented setup combines performance surpassing FT-IR spectroscopy with large applicable optical paths and coverage of the relevant spectral range for protein analysis. This holds high potential for future EC-QCL-based protein studies, including the investigation of dynamic secondary structure changes and chemometrics-based protein quantification in complex matrices.

External cavity-quantum cascade laser infrared spectroscopy for secondary structure analysis of proteins at low concentrations

PubMed Central

Schwaighofer, Andreas; Alcaráz, Mirta R.; Araman, Can; Goicoechea, Héctor; Lendl, Bernhard

2016-01-01

Fourier transform infrared (FTIR) and circular dichroism (CD) spectroscopy are analytical techniques employed for the analysis of protein secondary structure. The use of CD spectroscopy is limited to low protein concentrations (<2 mg ml−1), while FTIR spectroscopy is commonly used in a higher concentration range (>5 mg ml−1). Here we introduce a quantum cascade laser (QCL)-based IR transmission setup for analysis of protein and polypeptide secondary structure at concentrations as low as 0.25 mg ml−1 in deuterated buffer solution. We present dynamic QCL-IR spectra of the temperature-induced α-helix to β-sheet transition of poly-L-lysine. The concentration dependence of the α-β transition temperature between 0.25 and 10 mg ml−1 was investigated by QCL-IR, FTIR and CD spectroscopy. By using QCL-IR spectroscopy it is possible to perform IR spectroscopic analysis in the same concentration range as CD spectroscopy, thus enabling a combined analysis of biomolecules secondary structure by CD and IR spectroscopy. PMID:27633337

External cavity-quantum cascade laser infrared spectroscopy for secondary structure analysis of proteins at low concentrations.

PubMed

Schwaighofer, Andreas; Alcaráz, Mirta R; Araman, Can; Goicoechea, Héctor; Lendl, Bernhard

2016-09-16

Fourier transform infrared (FTIR) and circular dichroism (CD) spectroscopy are analytical techniques employed for the analysis of protein secondary structure. The use of CD spectroscopy is limited to low protein concentrations (<2 mg ml(-1)), while FTIR spectroscopy is commonly used in a higher concentration range (>5 mg ml(-1)). Here we introduce a quantum cascade laser (QCL)-based IR transmission setup for analysis of protein and polypeptide secondary structure at concentrations as low as 0.25 mg ml(-1) in deuterated buffer solution. We present dynamic QCL-IR spectra of the temperature-induced α-helix to β-sheet transition of poly-L-lysine. The concentration dependence of the α-β transition temperature between 0.25 and 10 mg ml(-1) was investigated by QCL-IR, FTIR and CD spectroscopy. By using QCL-IR spectroscopy it is possible to perform IR spectroscopic analysis in the same concentration range as CD spectroscopy, thus enabling a combined analysis of biomolecules secondary structure by CD and IR spectroscopy.

Validation of ATR FT-IR to identify polymers of plastic marine debris, including those ingested by marine organisms

USGS Publications Warehouse

Jung, Melissa R.; Horgen, F. David; Orski, Sara V.; Rodriguez, Viviana; Beers, Kathryn L.; Balazs, George H.; Jones, T. Todd; Work, Thierry M.; Brignac, Kayla C.; Royer, Sarah-Jeanne; Hyrenbach, David K.; Jensen, Brenda A.; Lynch, Jennifer M.

2018-01-01

Polymer identification of plastic marine debris can help identify its sources, degradation, and fate. We optimized and validated a fast, simple, and accessible technique, attenuated total reflectance Fourier transform infrared spectroscopy (ATR FT-IR), to identify polymers contained in plastic ingested by sea turtles. Spectra of consumer good items with known resin identification codes #1–6 and several #7 plastics were compared to standard and raw manufactured polymers. High temperature size exclusion chromatography measurements confirmed ATR FT-IR could differentiate these polymers. High-density (HDPE) and low-density polyethylene (LDPE) discrimination is challenging but a clear step-by-step guide is provided that identified 78% of ingested PE samples. The optimal cleaning methods consisted of wiping ingested pieces with water or cutting. Of 828 ingested plastics pieces from 50 Pacific sea turtles, 96% were identified by ATR FT-IR as HDPE, LDPE, unknown PE, polypropylene (PP), PE and PP mixtures, polystyrene, polyvinyl chloride, and nylon.

Biochemical Monitoring of Spinal Cord Injury by FT-IR Spectroscopy—Effects of Therapeutic Alginate Implant in Rat Models

PubMed Central

Uckermann, Ortrud; Sitoci-Ficici, Kerim H.; Later, Robert; Beiermeister, Rudolf; Doberenz, Falko; Gelinsky, Michael; Leipnitz, Elke; Schackert, Gabriele; Koch, Edmund; Sablinskas, Valdas; Steiner, Gerald; Kirsch, Matthias

2015-01-01

Spinal cord injury (SCI) induces complex biochemical changes, which result in inhibition of nervous tissue regeneration abilities. In this study, Fourier-transform infrared (FT-IR) spectroscopy was applied to assess the outcomes of implants made of a novel type of non-functionalized soft calcium alginate hydrogel in a rat model of spinal cord hemisection (n = 28). Using FT-IR spectroscopic imaging, we evaluated the stability of the implants and the effects on morphology and biochemistry of the injured tissue one and six months after injury. A semi-quantitative evaluation of the distribution of lipids and collagen showed that alginate significantly reduced injury-induced demyelination of the contralateral white matter and fibrotic scarring in the chronic state after SCI. The spectral information enabled to detect and localize the alginate hydrogel at the lesion site and proved its long-term persistence in vivo. These findings demonstrate a positive impact of alginate hydrogel on recovery after SCI and prove FT-IR spectroscopic imaging as alternative method to evaluate and optimize future SCI repair strategies. PMID:26559822

The use of FT-IR reflection-absorbance spectroscopy to study photochemical degradation of polymeric coatings on mirrors

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

Webb, J.D.; Chughtai, A.R.; Czanderna, A.W.

1981-10-01

A technique is presented for in situ study of degradative changes in polymeric coatings on metallic substrates. The technique uses a controlled environment chamber in conjunction with a Fourier-transform infrared (FT-IR) spectrophotometer. The chamber design permits collection of IR reflection-absorbance spectra from a sample undergoing exposure to controlled ultraviolet (UV) radiation, gas mixtures, and temperatures. Initial data presented confirm the ability of the technique to provide information regarding the bulk photochemistry of bisphenol-A polycarbonate coatings on gold and aluminum substrates. Refinements of this technique should allow a detailed kinetic study of degradative reactions at the polymer/metal interface.

Use of FT-IR reflection-absorbance spectroscopy to study photochemical degradation of polymeric coatings on mirrors

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

Webb, J D; Schissel, P; Czanderna, A W

1981-01-01

A technique is presented for in situ study of degradative changes in polymeric coatings on metallic substrates. The technique uses a controlled environment chamber in conjunction with a Fourier-transform infrared (FT-IR) spectrophotometer. The chamber design permits collection of IR reflection-absorbance spectra from a sample undergoing exposure to controlled ultraviolet (uv) radiation, gas mixtures, and temperatures. Initial data presented confirm the ability of the technique to provide information regarding the bulk photochemistry of bisphenol-A polycarbonate coatings on gold and aluminum substrates. Refinements of this technique should allow a detailed kinetic study of degradative reactions at the polymer/metal interface.

QUANTITATIVE FOURIER TRANSFORM INFRARED SPECTROSCOPIC INVESTIGATION OF HUMIC SUBSTANCE FUNCTIONAL GROUP COMPOSITION

EPA Science Inventory

Infrared (IR) spectroscopy has been widely used for the structural investigation of humic substances. Although Fourier Transform Infrared (FTIR) instrumentation has been available for sometime, relatively little work with these instruments has been reported for humic substances,...

Investigating the biochemical progression of liver disease through fibrosis, cirrhosis, dysplasia, and hepatocellular carcinoma using Fourier transform infrared spectroscopic imaging

NASA Astrophysics Data System (ADS)

Sreedhar, Hari; Pant, Mamta; Ronquillo, Nemencio R.; Davidson, Bennett; Nguyen, Peter; Chennuri, Rohini; Choi, Jacqueline; Herrera, Joaquin A.; Hinojosa, Ana C.; Jin, Ming; Kajdacsy-Balla, Andre; Guzman, Grace; Walsh, Michael J.

2014-03-01

Hepatocellular carcinoma (HCC) is the most common form of primary hepatic carcinoma. HCC ranks the fourth most prevalent malignant tumor and the third leading cause of cancer related death in the world. Hepatocellular carcinoma develops in the context of chronic liver disease and its evolution is characterized by progression through intermediate stages to advanced disease and possibly even death. The primary sequence of hepatocarcinogenesis includes the development of cirrhosis, followed by dysplasia, and hepatocellular carcinoma.1 We addressed the utility of Fourier Transform Infrared (FT-IR) spectroscopic imaging, both as a diagnostic tool of the different stages of the disease and to gain insight into the biochemical process associated with disease progression. Tissue microarrays were obtained from the University of Illinois at Chicago tissue bank consisting of liver explants from 12 transplant patients. Tissue core biopsies were obtained from each explant targeting regions of normal, liver cell dysplasia including large cell change and small cell change, and hepatocellular carcinoma. We obtained FT-IR images of these tissues using a modified FT-IR system with high definition capabilities. Firstly, a supervised spectral classifier was built to discriminate between normal and cancerous hepatocytes. Secondly, an expanded classifier was built to discriminate small cell and large cell changes in liver disease. With the emerging advances in FT-IR instrumentation and computation there is a strong drive to develop this technology as a powerful adjunct to current histopathology approaches to improve disease diagnosis and prognosis.

Supervision of Ethylene Propylene Diene M-Class (EPDM) Rubber Vulcanization and Recovery Processes Using Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Spectroscopy and Multivariate Analysis.

PubMed

Riba Ruiz, Jordi-Roger; Canals, Trini; Cantero, Rosa

2017-01-01

Ethylene propylene diene monomer (EPDM) rubber is widely used in a diverse type of applications, such as the automotive, industrial and construction sectors among others. Due to its appealing features, the consumption of vulcanized EPDM rubber is growing significantly. However, environmental issues are forcing the application of devulcanization processes to facilitate recovery, which has led rubber manufacturers to implement strict quality controls. Consequently, it is important to develop methods for supervising the vulcanizing and recovery processes of such products. This paper deals with the supervision process of EPDM compounds by means of Fourier transform mid-infrared (FT-IR) spectroscopy and suitable multivariate statistical methods. An expedited and nondestructive classification approach was applied to a sufficient number of EPDM samples with different applied processes, that is, with and without application of vulcanizing agents, vulcanized samples, and microwave treated samples. First the FT-IR spectra of the samples is acquired and next it is processed by applying suitable feature extraction methods, i.e., principal component analysis and canonical variate analysis to obtain the latent variables to be used for classifying test EPDM samples. Finally, the k nearest neighbor algorithm was used in the classification stage. Experimental results prove the accuracy of the proposed method and the potential of FT-IR spectroscopy in this area, since the classification accuracy can be as high as 100%.

Differentiation between probiotic and wild-type Bacillus cereus isolates by antibiotic susceptibility test and Fourier transform infrared spectroscopy (FT-IR).

PubMed

Mietke, Henriette; Beer, W; Schleif, Julia; Schabert, G; Reissbrodt, R

2010-05-30

Animal feed often contains probiotic Bacillus strains used as feed additives. Spores of the non-pathogenic B. cereus var. toyoi (product name Toyocerin) are used. Distinguishing between toxic wild-type Bacillus cereus strains and this probiotic strain is essential for evaluating the quality and risk of feed. Bacillus cereus CIP 5832 (product name Paciflor was used as probiotic strain until 2001. The properties of the two probiotic strains are quite similar. Differentiating between probiotic strains and wild-type B. cereus strains is not easy. ss-lactam antibiotics such as penicillin and cefamandole exhibit an inhibition zone in the agar diffusion test of probiotic B. cereus strains which are not seen for wild-type strains. Therefore, performing the agar diffusion test first may make sense before FT-IR testing. When randomly checking these strains by Fourier transform infrared spectroscopy (FT-IR), the probiotic B. cereus strains were separated from wild-type B. cereus/B. thuringiensis/B. mycoides/B. weihenstephanensis strains by means of hierarchical cluster analysis. The discriminatory information was contained in the spectral windows 3000-2800 cm(-1) ("fatty acid region"), 1200-900 cm(-1) ("carbohydrate region") and 900-700 cm(-1) ("fingerprint region"). It is concluded that FT-IR spectroscopy can be used for the rapid quality control and risk analysis of animal feed containing probiotic B. cereus strains. (c) 2010 Elsevier B.V. All rights reserved.

Exploring Geographical Differentiation of the Hoelen Medicinal Mushroom, Wolfiporia extensa (Agaricomycetes), Using Fourier-Transform Infrared Spectroscopy Combined with Multivariate Analysis.

PubMed

Li, Yan; Zhang, Ji; Zhao, Yanli; Liu, Honggao; Wang, Yuanzhong; Jin, Hang

2016-01-01

In this study the geographical differentiation of dried sclerotia of the medicinal mushroom Wolfiporia extensa, obtained from different regions in Yunnan Province, China, was explored using Fourier-transform infrared (FT-IR) spectroscopy coupled with multivariate data analysis. The FT-IR spectra of 97 samples were obtained for wave numbers ranging from 4000 to 400 cm-1. Then, the fingerprint region of 1800-600 cm-1 of the FT-IR spectrum, rather than the full spectrum, was analyzed. Different pretreatments were applied on the spectra, and a discriminant analysis model based on the Mahalanobis distance was developed to select an optimal pretreatment combination. Two unsupervised pattern recognition procedures- principal component analysis and hierarchical cluster analysis-were applied to enhance the authenticity of discrimination of the specimens. The results showed that excellent classification could be obtained after optimizing spectral pretreatment. The tested samples were successfully discriminated according to their geographical locations. The chemical properties of dried sclerotia of W. extensa were clearly dependent on the mushroom's geographical origins. Furthermore, an interesting finding implied that the elevations of collection areas may have effects on the chemical components of wild W. extensa sclerotia. Overall, this study highlights the feasibility of FT-IR spectroscopy combined with multivariate data analysis in particular for exploring the distinction of different regional W. extensa sclerotia samples. This research could also serve as a basis for the exploitation and utilization of medicinal mushrooms.

High throughput operando studies using Fourier transform infrared imaging and Raman spectroscopy.

PubMed

Li, Guosheng; Hu, Dehong; Xia, Guanguang; White, J M; Zhang, Conrad

2008-07-01

A prototype high throughput operando (HTO) reactor designed and built for catalyst screening and characterization combines Fourier transform infrared (FT-IR) imaging and Raman spectroscopy in operando conditions. Using a focal plane array detector (HgCdTe focal plane array, 128x128 pixels, and 1610 Hz frame rate) for the FT-IR imaging system, the catalyst activity and selectivity of all parallel reaction channels can be simultaneously followed. Each image data set possesses 16 384 IR spectra with a spectral range of 800-4000 cm(-1) and with an 8 cm(-1) resolution. Depending on the signal-to-noise ratio, 2-20 s are needed to generate a full image of all reaction channels for a data set. Results on reactant conversion and product selectivity are obtained from FT-IR spectral analysis. Six novel Raman probes, one for each reaction channel, were specially designed and house built at Pacific Northwest National Laboratory, to simultaneously collect Raman spectra of the catalysts and possible reaction intermediates on the catalyst surface under operando conditions. As a model system, methanol partial oxidation reaction on silica-supported molybdenum oxide (MoO3SiO2) catalysts has been studied under different reaction conditions to demonstrate the performance of the HTO reactor.

Diagnostics of normal and cancer tissues by fiberoptic evanescent wave Fourier transform IR (FEW-FTIR) spectroscopy

NASA Astrophysics Data System (ADS)

Afanasyeva, Natalia I.

1998-06-01

Fourier Transform Infrared (FTIR) Spectroscopy using optical fibers operated in the attenuated total reflection (ATR) regime in the mid-IR region in the range 850 to 4000 cm-1 has recently found an application in the noninvasive diagnostics of tissues in vivo. The method is suitable for nondestructive, nontoxic, fast (seconds), direct measurements of the spectra of normal and pathological tissues in vitro, ex vivo, and in vivo in real time. The aim of our studies is the express testing of various tumor tissues at the early stages of their development. The method is expected to be further developed for endoscopic and biopsy applications as well as for the research of different materials.

ATR-FTIR spectroscopy reveals polycyclic aromatic hydrocarbon contamination despite relatively pristine site characteristics: Results of a field study in the Niger Delta.

PubMed

Obinaju, Blessing E; Martin, Francis L

2016-01-01

Fourier-transform infrared (FTIR) spectroscopy is an emerging technique to detect biochemical alterations in biological tissues, particularly changes due to sub-lethal exposures to environmental contaminants. We have previously shown the potential of attenuated total reflection FTIR (ATR-FTIR) spectroscopy to detect real-time exposure to contaminants in sentinel organisms as well as the potential to relate spectral alterations to the presence of specific environmental agents. In this study based in the Niger Delta (Nigeria), changes occurring in fish tissues as a result of polycyclic aromatic hydrocarbon (PAH) exposure at contaminated sites are compared to the infrared (IR) spectra of the tissues obtained from a relatively pristine site. Multivariate analysis revealed that PAH contamination could be occurring at the pristine site, based on the IR spectra and significant (P<0.0001) differences between sites. The study provides evidence of the IR spectroscopy techniques' sensitivity and supports their potential application in environmental biomonitoring. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of Low Carbohydrate High Protein (LCHP) diet on atherosclerotic plaque phenotype in ApoE/LDLR-/- mice: FT-IR and Raman imaging.

PubMed

Wrobel, T P; Marzec, K M; Chlopicki, S; Maślak, E; Jasztal, A; Franczyk-Żarów, M; Czyżyńska-Cichoń, I; Moszkowski, T; Kostogrys, R B; Baranska, M

2015-09-22

Low Carbohydrate High Protein (LCHP) diet displays pro-atherogenic effects, however, the exact mechanisms involved are still unclear. Here, with the use of vibrational imaging, such as Fourier transform infrared (FT-IR) and Raman (RS) spectroscopies, we characterize biochemical content of plaques in Brachiocephalic Arteries (BCA) from ApoE/LDLR(-/-) mice fed LCHP diet as compared to control, recomended by American Institute of Nutrition, AIN diet. FT-IR images were taken from 6-10 sections of BCA from each mice and were complemented with RS measurements with higher spatial resolution of chosen areas of plaque sections. In aortic plaques from LCHP fed ApoE/LDLR(-/-) mice, the content of cholesterol and cholesterol esters was increased, while that of proteins was decreased as evidenced by global FT-IR analysis. High resolution imaging by RS identified necrotic core/foam cells, lipids (including cholesterol crystals), calcium mineralization and fibrous cap. The decreased relative thickness of the outer fibrous cap and the presence of buried caps were prominent features of the plaques in ApoE/LDLR(-/-) mice fed LCHP diet. In conclusion, FT-IR and Raman-based imaging provided a complementary insight into the biochemical composition of the plaque suggesting that LCHP diet increased plaque cholesterol and cholesterol esters contents of atherosclerotic plaque, supporting the cholesterol-driven pathogenesis of LCHP-induced atherogenesis.

Nondestructive Handheld Fourier Transform Infrared (FT-IR) Analysis of Spectroscopic Changes and Multivariate Modeling of Thermally Degraded Plain Portland Cement Concrete and its Slag and Fly Ash-Based Analogs.

PubMed

Leung Tang, Pik; Alqassim, Mohammad; Nic Daéid, Niamh; Berlouis, Leonard; Seelenbinder, John

2016-05-01

Concrete is by far the world's most common construction material. Modern concrete is a mixture of industrial pozzolanic cement formulations and aggregate fillers. The former acts as the glue or binder in the final inorganic composite; however, when exposed to a fire the degree of concrete damage is often difficult to evaluate nondestructively. Fourier transform infrared (FT-IR) spectroscopy through techniques such as transmission, attenuated total reflectance, and diffuse reflectance have been rarely used to evaluate thermally damaged concrete. In this paper, we report on a study assessing the thermal damage of concrete via the use of a nondestructive handheld FT-IR with a diffuse reflectance sample interface. In situ measurements can be made on actual damaged areas, without the need for sample preparation. Separate multivariate models were developed to determine the equivalent maximal temperature endured for three common industrial concrete formulations. The concrete mixtures were successfully modeled displaying high predictive power as well as good specificity. This has potential uses in forensic investigation and remediation services particularly for fires in buildings. © The Author(s) 2016.

Application of MCR-ALS to reveal intermediate conformations in the thermally induced α-β transition of poly-L-lysine monitored by FT-IR spectroscopy

NASA Astrophysics Data System (ADS)

Alcaráz, Mirta R.; Schwaighofer, Andreas; Goicoechea, Héctor; Lendl, Bernhard

2017-10-01

Temperature-induced conformational transitions of poly-L-lysine were monitored with Fourier-transform infrared (FT-IR) spectroscopy between 10 °C and 70 °C. Chemometric analysis of dynamic IR spectra was performed by multivariate curve analysis-alternating least squares (MCR-ALS) of the amide I‧ and amide II‧ spectral region. With this approach, the pure spectral and concentration profiles of the conformational transition were obtained. Beside the initial α-helical, the intermediate random coil/extended helices and the final β-sheet structure, an additional intermediate PLL conformation was identified and attributed to a transient β-sheet structure.

Fast quality control of Herba Epimedii by using Fourier transform infrared spectroscopy

NASA Astrophysics Data System (ADS)

Pei, Li-Kuan; Sun, Su-Qin; Guo, Bao-Lin; Huang, Wen-Hua; Xiao, Pei-Gen

2008-07-01

Herba Epimedii is a well-known traditional Chinese medicine (TCM) having the effect of nourishing the kidney and strengthening the 'Yang'. Its primary effective constituents are considered to be the 8-prenyl flavonols, which can be assorted into 4'-methoxyl-prenylflavonols (MPFs) and 4'-hydroxyl-prenylflavonols (HPFs), according to the group (methoxyl or hydroxyl) located at 4' in their structures. The Fourier transform infrared spectroscopy (FT-IR) has been widely used in the researches of TCMs. In the present study, the FT-IR was attempted to be applied in the quality control of Herba Epimedii. We compared the IR spectra of 17 pure flavonoids, of which eight were derived from Herba Epimedii, and found a characteristic absorption peak at 1259 ± 1 cm -1, corresponding to the MPFs, the major 8-prenyl flavonols in the aerial parts of the Epimedium species. This peak could also be found in the IR spectra of both the herbal samples and their 70% ethanol extracts. Moreover, the intensity of this peak was in the direct correlation with the total content of MPFs. The correlation values, representing the semblance of two spectra, of the IR spectrum of herbal sample and icariin, in the range of 1280-1200 cm -1, had been established to be a good index for the quality control of the herbs. Accordingly, a correlation value of not less than 0.50 could be used as the essential screening criteria for the herbs. The FT-IR could be used for the fast and effective quality control of Herba Epimedii.

Attenuated total internal reflection infrared microspectroscopic imaging using a large-radius germanium internal reflection element and a linear array detector.

PubMed

Patterson, Brian M; Havrilla, George J

2006-11-01

The number of techniques and instruments available for Fourier transform infrared (FT-IR) microspectroscopic imaging has grown significantly over the past few years. Attenuated total internal reflectance (ATR) FT-IR microspectroscopy reduces sample preparation time and has simplified the analysis of many difficult samples. FT-IR imaging has become a powerful analytical tool using either a focal plane array or a linear array detector, especially when coupled with a chemometric analysis package. The field of view of the ATR-IR microspectroscopic imaging area can be greatly increased from 300 x 300 microm to 2500 x 2500 microm using a larger internal reflection element of 12.5 mm radius instead of the typical 1.5 mm radius. This gives an area increase of 70x before aberrant effects become too great. Parameters evaluated include the change in penetration depth as a function of beam displacement, measurements of the active area, magnification factor, and change in spatial resolution over the imaging area. Drawbacks such as large file size will also be discussed. This technique has been successfully applied to the FT-IR imaging of polydimethylsiloxane foam cross-sections, latent human fingerprints, and a model inorganic mixture, which demonstrates the usefulness of the method for pharmaceuticals.

Chemometric analysis of attenuated total reflectance infrared spectra of Proteus mirabilis strains with defined structures of LPS.

PubMed

Zarnowiec, Paulina; Mizera, Andrzej; Chrapek, Magdalena; Urbaniak, Mariusz; Kaca, Wieslaw

2016-07-01

Proteus spp. strains are some of the most important pathogens associated with complicated urinary tract infections and bacteremia affecting patients with immunodeficiency and long-term urinary catheterization. For epidemiological purposes, various molecular typing methods have been developed for this pathogen. However, these methods are labor intensive and time consuming. We evaluated a new method of differentiation between strains. A collection of Proteus spp. strains was analyzed by attenuated total reflectance Fourier transform infrared (ATR FT-IR) spectroscopy in the mid-infrared region. ATR FT-IR spectroscopy used in conjunction with a diamond ATR accessory directly produced the biochemical profile of the surface chemistry of bacteria. We conclude that a combination of ATR FT-IR spectroscopy and mathematical modeling provides a fast and reliable alternative for discrimination between Proteus isolates, contributing to epidemiological research. © The Author(s) 2016.

Effects of Er:YAG laser irradiation on human dentin: polarizing microscopic, light microscopic and microradiographic observations, and FT-IR analysis.

PubMed

Ishizaka, Yaeko; Eguro, Toru; Maeda, Toru; Tanaka, Hisayoshi

2002-01-01

The effects of Er:YAG laser irradiation on dentin have not been sufficiently investigated. The purpose of this study was to investigate the effects of Er:YAG laser irradiation on dentin. After cavities were prepared using Er:YAG laser irradiation or rotary cutting instruments, histological observations of cavity-floor dentin utilizing polarizing microscopy, microradiography and light microscopy, and analysis of composition of cavity-floor dentin using Fourier-transformed (FT-IR) spectrometry were conducted. In the laser-treated side, a deeply stained basophilic layer was observed. The number of odontoblastic processes present was obviously less in the laser-treated side than in the bur-treated side. FT-IR analysis revealed that compared to the bur-treated side, a broad background peak at around 1,600 cm(-1) was present. Er:YAG laser irradiation might have denatured the organic materials of dentin. Copyright 2002 Wiley-Liss, Inc.

Changes in Liver Cell DNA Methylation Status in Diabetic Mice Affect Its FT-IR Characteristics

PubMed Central

Vidal, Benedicto de Campos; Ghiraldini, Flávia Gerelli; Mello, Maria Luiza S.

2014-01-01

Background Lower levels of cytosine methylation have been found in the liver cell DNA from non-obese diabetic (NOD) mice under hyperglycemic conditions. Because the Fourier transform-infrared (FT-IR) profiles of dry DNA samples are differently affected by DNA base composition, single-stranded form and histone binding, it is expected that the methylation status in the DNA could also affect its FT-IR profile. Methodology/Principal Findings The DNA FT-IR signatures obtained from the liver cell nuclei of hyperglycemic and normoglycemic NOD mice of the same age were compared. Dried DNA samples were examined in an IR microspectroscope equipped with an all-reflecting objective (ARO) and adequate software. Conclusions/Significance Changes in DNA cytosine methylation levels induced by hyperglycemia in mouse liver cells produced changes in the respective DNA FT-IR profiles, revealing modifications to the vibrational intensities and frequencies of several chemical markers, including νas –CH3 stretching vibrations in the 5-methylcytosine methyl group. A smaller band area reflecting lower energy absorbed in the DNA was found in the hyperglycemic mice and assumed to be related to the lower levels of –CH3 groups. Other spectral differences were found at 1700–1500 cm−1 and in the fingerprint region, and a slight change in the DNA conformation at the lower DNA methylation levels was suggested for the hyperglycemic mice. The changes that affect cytosine methylation levels certainly affect the DNA-protein interactions and, consequently, gene expression in liver cells from the hyperglycemic NOD mice. PMID:25019512

Applications of Fourier transform infrared spectroscopy to quality control of the epoxy matrix

NASA Technical Reports Server (NTRS)

Antoon, M. K.; Starkey, K. M.; Koenig, J. L.

1979-01-01

The object of the paper is to demonstrate the utility of Fourier transform infrared (FT-IR) difference spectra for investigating the composition of a neat epoxy resin, hardener, and catalysts. The composition and degree of cross-linking of the cured matrix is also considered.

Novel FT-IR Microspectroscopic Census of Simple Starch Granules for Octenyl Succinate Ester Modification

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

Bai, Y.; Shi, Y; Wetzel, D

Fourier transform infrared (FT-IR) microspectroscopy was used to investigate reaction homogeneity of octenyl succinic anhydride modification on waxy maize starch and detect uniformity of blends of modified and native starches. For the first time, the level and uniformity of chemical substitution on individual starch granules were analyzed by FT-IR microspectroscopy. More than 100 starch granules of each sample were analyzed one by one by FT-IR microspectroscopy. In comparison to the native starch, modified starch had two additional bands at 1723 and 1563 cm{sup -1}, indicative of ester formation in the modified starch. For the 3% modification level, the degree ofmore » substitution (DS) was low (0.019) and the distribution of the ester group was not uniform among starch granules. For the modified starch with DS of 0.073, 99% of individual starch granules had a large carbonyl band area, indicating that most granules were modified to a sufficient extent that the presence of their carbonyl ester classified them individually as being modified. However, the octenyl succinate concentration varied between granules, suggesting that the reaction was not uniform. When modified starch (DS = 0.073) was blended with native starch (3:7, w/w) to achieve a mixture with an average DS of 0.019, FT-IR microspectroscopy was able to detect heterogeneity of octenyl succinate in the blend and determine the ratio of the modified starch to the native starch granules.« less

FT-IR quantification of the carbonyl functional group in aqueous-phase secondary organic aerosol from phenols

NASA Astrophysics Data System (ADS)

George, Kathryn M.; Ruthenburg, Travis C.; Smith, Jeremy; Yu, Lu; Zhang, Qi; Anastasio, Cort; Dillner, Ann M.

2015-01-01

Recent findings suggest that secondary organic aerosols (SOA) formed from aqueous-phase reactions of some organic species, including phenols, contribute significantly to particulate mass in the atmosphere. In this study, we employ a Fourier transform infrared (FT-IR) spectroscopic technique to identify and quantify the functional group makeup of phenolic SOA. Solutions containing an oxidant (hydroxyl radical or 3,4-dimethoxybenzaldehyde) and either one phenol (phenol, guaiacol, or syringol) or a mixture of phenols mimicking softwood or hardwood emissions were illuminated to make SOA, atomized, and collected on a filter. We produced laboratory standards of relevant organic compounds in order to develop calibrations for four functional groups: carbonyls (Cdbnd O), saturated C-H, unsaturated C-H and O-H. We analyzed the SOA samples with transmission FT-IR to identify and determine the amounts of the four functional groups. The carbonyl functional group accounts for 3-12% of the SOA sample mass in single phenolic SOA samples and 9-14% of the SOA sample mass in mixture samples. No carbonyl functional groups are present in the initial reactants. Varying amounts of each of the other functional groups are observed. Comparing carbonyls measured by FT-IR (which could include aldehydes, ketones, esters, and carboxylic acids) with eight small carboxylic acids measured by ion chromatography indicates that the acids only account for an average of 20% of the total carbonyl reported by FT-IR.

Increasing the quantitative credibility of open-path FT-IR spectroscopic data with focus on several properties of the background spectrum

USDA-ARS?s Scientific Manuscript database

The choice of the type of background spectrum affects the credibility of open-path Fourier transform infrared (OP/FT-IR) spectroscopic data, and consequently the quality of data analysis. We systematically investigated several properties of the background spectrum. The results show that a short-pa...

Development of acceptance criteria for batches of silane primer for external tank thermal protection system bonding applications

NASA Technical Reports Server (NTRS)

Mikes, F.

1984-01-01

Silane primers for use as thermal protection on external tanks were subjected to various analytic techniques to determine the most effective testing method for silane lot evaluation. The analytic methods included high performance liquid chromatography, gas chromatography, thermogravimetry (TGA), and fourier transform infrared spectroscopy (FTIR). It is suggested that FTIR be used as the method for silane lot evaluation. Chromatograms, TGA profiles, bar graphs showing IR absorbances, and FTIR spectra are presented.

FT-IR and Zeta potential measurements on TiO nanoparticles

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

Singh, Jaiveer; Rathore, Ravi; Kaurav, Netram, E-mail: netramkaurav@yahoo.co.uk

2016-05-23

In the present investigation, ultrafine TiO particles have been synthesized successfully by thermal decomposition method. The sample was characterized by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. As-synthesized TiO nanoparticles have a cubic structure as characterized by power X-ray diffraction (XRD), which shows that TiO nanoparticles have narrow size distribution with particle size 11.5 nm. FTIR data shows a strong peak at 1300 cm{sup −1}, assignable to the Ti-O stretching vibrations mode.

Direct and simultaneous detection of organic and inorganic ingredients in herbal powder preparations by Fourier transform infrared microspectroscopic imaging

NASA Astrophysics Data System (ADS)

Chen, Jian-bo; Sun, Su-qin; Tang, Xu-dong; Zhang, Jing-zhao; Zhou, Qun

2016-08-01

Herbal powder preparation is a kind of widely-used herbal product in the form of powder mixture of herbal ingredients. Identification of herbal ingredients is the first and foremost step in assuring the quality, safety and efficacy of herbal powder preparations. In this research, Fourier transform infrared (FT-IR) microspectroscopic identification method is proposed for the direct and simultaneous recognition of multiple organic and inorganic ingredients in herbal powder preparations. First, the reference spectrum of characteristic particles of each herbal ingredient is assigned according to FT-IR results and other available information. Next, a statistical correlation threshold is determined as the lower limit of correlation coefficients between the reference spectrum and a larger number of calibration characteristic particles. After validation, the reference spectrum and correlation threshold can be used to identify herbal ingredient in mixture preparations. A herbal ingredient is supposed to be present if correlation coefficients between the reference spectrum and some sample particles are above the threshold. Using this method, all kinds of herbal materials in powder preparation Kouqiang Kuiyang San are identified successfully. This research shows the potential of FT-IR microspectroscopic identification method for the accurate and quick identification of ingredients in herbal powder preparations.

Cotton fiber quality characterization with light scattering and fourier transform infrared techniques.

PubMed

Thomasson, J A; Manickavasagam, S; Mengüç, M P

2009-03-01

Fiber quality measurement is critical to assessing the value of a bale of cotton for various textile purposes. An instrument that could measure numerous cotton quality properties by optical means could be made simpler and faster than current fiber quality measurement instruments, and it might be more amenable to on-line measurement at processing facilities. To that end, a laser system was used to investigate cotton fiber samples with respect to electromagnetic scattering at various wavelengths, polarization angles, and scattering angles. A Fourier transform infrared (FT-IR) instrument was also used to investigate the transmission of electromagnetic energy at various mid-infrared wavelengths. Cotton samples were selected to represent a wide range of micronaire values. Varying the wavelength of the laser at a fixed polarization resulted in little variation in scattered light among the cotton samples. However, varying the polarization at a fixed wavelength produced notable variation, indicating that polarization might be used to differentiate among cotton samples with respect to certain fiber properties. The FT-IR data in the 12 to 22 microm range produced relatively large differences in the amount of scattered light among all samples, and FT-IR data at certain combinations of fixed wavelengths were highly linearly related to certain measures of cotton quality including micronaire.

Comparison and validation of Fourier transform infrared spectroscopic methods for monitoring secondary cell wall cellulose from cotton fibers

USDA-ARS?s Scientific Manuscript database

The amount of secondary cell wall (SCW) cellulose in the fiber affects the quality and commercial value of cotton. Accurate assessments of SCW cellulose are essential for improving cotton fibers. Fourier Transform Infrared (FT-IR) spectroscopy enables distinguishing SCW from other cell wall componen...

Secondary cell wall development in cotton fibers as examined with attenuated total reflection Fourier transform infrared spectroscopy

USDA-ARS?s Scientific Manuscript database

Cotton fibers harvested at 18, 20, 24, 28, 32, 36 and 40 days after flowering were examined using attenuated total reflection Fourier transform-infrared (ATR FT-IR) spectroscopy. The selected harvesting points coincide with secondary cell wall (SCW) development in the fibers. Progressive but moderat...

In situ FTIR microspectroscopy of extravasated blood-damaged brain tissue

NASA Astrophysics Data System (ADS)

Wetzel, David L.; Le Vine, Steven M.

1994-01-01

Fourier transform infrared (FT-IR) microspectroscopy enables the collection of infrared spectra from microscopic regions of tissue sections. The objectives of this study were to utilize FT-IR microspectroscopy to analyze the spatial distribution of chemical changes that result from the extravasation of blood into the brain and to determine if products of free radical damage are associated with the damaged areas. An animal model that involves the injection of blood into the white matter of rat brains was used. Maps depicting the relative concentrations of chemical functional groups of lesioned sites and surrounding areas were made. Significant decreases were observed for CH2, C equals O, P equals O, and HO-C-H functional groups at the lesioned site and penumbra regions compared to the neighboring normal tissue areas.

Raman and Fourier Transform Infrared (FT-IR) Mineral to Matrix Ratios Correlate with Physical Chemical Properties of Model Compounds and Native Bone Tissue.

PubMed

Taylor, Erik A; Lloyd, Ashley A; Salazar-Lara, Carolina; Donnelly, Eve

2017-10-01

Raman and Fourier transform infrared (FT-IR) spectroscopic imaging techniques can be used to characterize bone composition. In this study, our objective was to validate the Raman mineral:matrix ratios (ν 1 PO 4 :amide III, ν 1 PO 4 :amide I, ν 1 PO 4 :Proline + hydroxyproline, ν 1 PO 4 :Phenylalanine, ν 1 PO 4 :δ CH 2 peak area ratios) by correlating them to ash fraction and the IR mineral:matrix ratio (ν 3 PO 4 :amide I peak area ratio) in chemical standards and native bone tissue. Chemical standards consisting of varying ratios of synthetic hydroxyapatite (HA) and collagen, as well as bone tissue from humans, sheep, and mice, were characterized with confocal Raman spectroscopy and FT-IR spectroscopy and gravimetric analysis. Raman and IR mineral:matrix ratio values from chemical standards increased reciprocally with ash fraction (Raman ν 1 PO 4 /Amide III: P < 0.01, R 2  = 0.966; Raman ν 1 PO 4 /Amide I: P < 0.01, R 2  = 0.919; Raman ν 1 PO 4 /Proline + Hydroxyproline: P < 0.01, R 2  = 0.976; Raman ν 1 PO 4 /Phenylalanine: P < 0.01, R 2  = 0.911; Raman ν 1 PO 4 /δ CH 2 : P < 0.01, R 2  = 0.894; IR P < 0.01, R 2  = 0.91). Fourier transform infrared mineral:matrix ratio values from native bone tissue were also similar to theoretical mineral:matrix ratio values for a given ash fraction. Raman and IR mineral:matrix ratio values were strongly correlated ( P < 0.01, R 2  = 0.82). These results were confirmed by calculating the mineral:matrix ratio for theoretical IR spectra, developed by applying the Beer-Lambert law to calculate the relative extinction coefficients of HA and collagen over the same range of wavenumbers (800-1800 cm -1 ). The results confirm that the Raman mineral:matrix bone composition parameter correlates strongly to ash fraction and to its IR counterpart. Finally, the mineral:matrix ratio values of the native bone tissue are similar to those of both chemical standards and theoretical values, confirming the biological relevance of the chemical standards and the characterization techniques.

Final technical report. In-situ FT-IR monitoring of a black liquor recovery boiler

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

James Markham; Joseph Cosgrove; David Marran

1999-05-31

This project developed and tested advanced Fourier transform infrared (FT-IR) instruments for process monitoring of black liquor recovery boilers. The state-of-the-art FT-IR instruments successfully operated in the harsh environment of a black liquor recovery boiler and provided a wealth of real-time process information. Concentrations of multiple gas species were simultaneously monitored in-situ across the combustion flow of the boiler and extractively at the stack. Sensitivity to changes of particulate fume and carryover levels in the process flow were also demonstrated. Boiler set-up and operation is a complex balance of conditions that influence the chemical and physical processes in the combustionmore » flow. Operating parameters include black liquor flow rate, liquor temperature, nozzle pressure, primary air, secondary air, tertiary air, boiler excess oxygen and others. The in-process information provided by the FT-IR monitors can be used as a boiler control tool since species indicative of combustion efficiency (carbon monoxide, methane) and pollutant emissions (sulfur dioxide, hydrochloric acid and fume) were monitored in real-time and observed to fluctuate as operating conditions were varied. A high priority need of the U.S. industrial boiler market is improved measurement and control technology. The sensor technology demonstrated in this project is applicable to the need of industry.« less

IR spectroscopic characteristics of cell cycle and cell death probed by synchrotron radiation based Fourier transform IR spectromicroscopy

NASA Technical Reports Server (NTRS)

Holman, H. Y.; Martin, M. C.; Blakely, E. A.; Bjornstad, K.; McKinney, W. R.

2000-01-01

Synchrotron radiation based Fourier transform IR (SR-FTIR) spectromicroscopy allows the study of individual living cells with a high signal to noise ratio. Here we report the use of the SR-FTIR technique to investigate changes in IR spectral features from individual human lung fibroblast (IMR-90) cells in vitro at different points in their cell cycle. Clear changes are observed in the spectral regions corresponding to proteins, DNA, and RNA as a cell changes from the G(1)-phase to the S-phase and finally into mitosis. These spectral changes include markers for the changing secondary structure of proteins in the cell, as well as variations in DNA/RNA content and packing as the cell cycle progresses. We also observe spectral features that indicate that occasional cells are undergoing various steps in the process of cell death. The dying or dead cell has a shift in the protein amide I and II bands corresponding to changing protein morphologies, and a significant increase in the intensity of an ester carbonyl C===O peak at 1743 cm(-1) is observed. Copyright John Wiley & Sons, Inc. Biopolymers (Biospectroscopy) 57: 329-335, 2000.

Comparison of Fiber Optic and Conduit Attenuated Total Reflection (ATR) Fourier Transform Infrared (FT-IR) Setup for In-Line Fermentation Monitoring.

PubMed

Koch, Cosima; Posch, Andreas E; Herwig, Christoph; Lendl, Bernhard

2016-12-01

The performance of a fiber optic and an optical conduit in-line attenuated total reflection mid-infrared (IR) probe during in situ monitoring of Penicillium chrysogenum fermentation were compared. The fiber optic probe was connected to a sealed, portable, Fourier transform infrared (FT-IR) process spectrometer via a plug-and-play interface. The optical conduit, on the other hand, was connected to a FT-IR process spectrometer via a knuckled probe with mirrors that had to be adjusted prior to each fermentation, which were purged with dry air. Penicillin V (PenV) and its precursor phenoxyacetic acid (POX) concentrations were determined by online high-performance liquid chromatography and the obtained concentrations were used as reference to build partial least squares regression models. Cross-validated root-mean-square errors of prediction were found to be 0.2 g L -1 (POX) and 0.19 g L -1 (PenV) for the fiber optic setup and 0.17 g L -1 (both POX and PenV) for the conduit setup. Higher noise-levels and spectrum-to-spectrum variations of the fiber optic setup lead to higher noise of estimated (i.e., unknown) POX and PenV concentrations than was found for the conduit setup. It seems that trade-off has to be made between ease of handling (fiber optic setup) and measurement accuracy (optical conduit setup) when choosing one of these systems for bioprocess monitoring. © The Author(s) 2016.

Rapid discrimination of extracts of Chinese propolis and poplar buds by FT-IR and 2D IR correlation spectroscopy

NASA Astrophysics Data System (ADS)

Wu, Yan-Wen; Sun, Su-Qin; Zhao, Jing; Li, Yi; Zhou, Qun

2008-07-01

The extract of Chinese propolis (ECP) has recently been adulterated with that of poplar buds (EPB), because most of ECP is derived from the poplar plant, and ECP and EPB have almost identical chemical compositions. It is very difficult to differentiate them by using the chromatographic methods such as high performance liquid chromatography (HPLC) and gas chromatography (GC). Therefore, how to effectively discriminate these two mixtures is a problem to be solved urgently. In this paper, a rapid method for discriminating ECP and EPB was established by the Fourier transform infrared (FT-IR) spectra combined with the two-dimensional infrared correlation (2D IR) analysis. Forty-three ECP and five EPB samples collected from different areas of China were analyzed by the FT-IR spectroscopy. All the ECP and EPB samples tested show similar IR spectral profiles. The significant differences between ECP and EPB appear in the region of 3000-2800 cm -1 of the spectra. Based on such differences, the two species were successfully classified with the soft independent modeling of class analogy (SIMCA) pattern recognition technique. Furthermore, these differences were well validated by a series of temperature-dependent dynamic FT-IR spectra and the corresponding 2D IR plots. The results indicate that the differences in these two natural products are caused by the amounts of long-chain alkyl compounds (including long-chain alkanes, long-chain alkyl esters and long chain alkyl alcohols) in them, rather than the flavonoid compounds, generally recognized as the bioactive substances of propolis. There are much more long-chain alkyl compounds in ECP than those in EPB, and the carbon atoms of the compounds in ECP remain in an order Z-shaped array, but those in EPB are disorder. It suggests that FT-IR and 2D IR spectroscopy can provide a valuable method for the rapid differentiation of similar natural products, ECP and EPB. The IR spectra could directly reflect the integrated chemical compositions of complicated mixtures, and it may be available for use in further chromatographic analysis.

Some critical aspects of FT-IR, TGA, powder XRD, EDAX and SEM studies of calcium oxalate urinary calculi.

PubMed

Joshi, Vimal S; Vasant, Sonal R; Bhatt, J G; Joshi, Mihir J

2014-06-01

Urinary calculi constitute one of the oldest afflictions of humans as well as animals, which are occurring globally. The calculi vary in shape, size and composition, which influence their clinical course. They are usually of the mixed-type with varying percentages of the ingredients. In medical management of urinary calculi, either the nature of calculi is to be known or the exact composition of calculi is required. In the present study, two selected calculi were recovered after surgery from two different patients for detailed examination and investigated by using Fourier-Transform infrared spectroscopy (FT-IR), thermo-gravimetric analysis (TGA), powder X-ray diffraction (XRD), scanning electron microscopy and energy dispersive analysis of X-rays (EDAX) techniques. The study demonstrated that the nature of urinary calculi and presence of major phase in mixed calculi could be identified by FT-IR, TGA and powder XRD, however, the exact content of various elements could be found by EDAX only.

Quantitative determination and evaluation of Paris polyphylla var. yunnanensis with different harvesting times using UPLC-UV-MS and FT-IR spectroscopy in combination with partial least squares discriminant analysis.

PubMed

Yang, Yuan-Gui; Zhang, Ji; Zhao, Yan-Li; Zhang, Jin-Yu; Wang, Yuan-Zhong

2017-07-01

A rapid method was developed and validated by ultra-performance liquid chromatography-triple quadrupole mass spectroscopy with ultraviolet detection (UPLC-UV-MS) for simultaneous determination of paris saponin I, paris saponin II, paris saponin VI and paris saponin VII. Partial least squares discriminant analysis (PLS-DA) based on UPLC and Fourier transform infrared (FT-IR) spectroscopy was employed to evaluate Paris polyphylla var. yunnanensis (PPY) at different harvesting times. Quantitative determination implied that the various contents of bioactive compounds with different harvesting times may lead to different pharmacological effects; the average content of total saponins for PPY harvested at 8 years was higher than that from other samples. The PLS-DA of FT-IR spectra had a better performance than that of UPLC for discrimination of PPY from different harvesting times. Copyright © 2016 John Wiley & Sons, Ltd.

FT-IR Spectroscopic Analysis of Normal and Malignant Human Oral Tissues

NASA Astrophysics Data System (ADS)

Krishnakumar, N.; Madhavan, R. Nirmal; Sumesh, P.; Palaniappan, Pl. Rm.; Venkatachalam, P.; Ramachandran, C. R.

2008-11-01

FT-IR spectroscopy has been used to explore the changes in the vibrational bands of normal and oral squamous cell carcinoma (OSCC) tissues in the region 4000-400 cm-1. Significant changes in the spectral features were observed. The spectral changes were the results of characteristics structural alterations at the molecular level in the malignant tissues. These alterations include structural changes of proteins and possible increase of its content, an increase in the nucleic-to-cytoplasm ratio, an increase in the relative amount of DNA, an increase in the rate of phosphorylation process induced by carcinogenesis, a loss of hydrogen bonding of the C-OH groups in the amino acid residues of proteins, a decrease in the relative amount of lipids compared to normal epithelial oral tissues. The results of the present study demonstrate that the FT-IR technique has the feasibility of discriminating malignant from normal tissues and other pathological states in a short period of time and may detect malignant transformation earlier than the standard histological examination stage.

Tracking chemical changes in a live cell: Biomedical applications of SR-FTIR spectromicroscopy

DOE PAGES

Holman, Hoi-Ying N.; Martin, Michael C.; McKinney, Wayne R.

2003-01-01

Synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectromicroscopy is a newly emerging bioanalytical and imaging tool. This unique technique provides mid-infrared (IR) spectra, hence chemical information, with high signal-to-noise at spatial resolutions as fine as 3 to 10 microns. Thus it enables researchers to locate, identify, and track specific chemical events within an individual living mammalian cell. Mid-IR photons are too low in energy (0.05-0.5 eV) to either break bonds or to cause ionization. In this review, we show that the synchrotron IR beam has no detectable effects on the short- and long-term viability, reproductive integrity, cell-cycle progression, and mitochondrial metabolismmore » in living human cells, and produces only minimal sample heating (<0.5°C). We will then present several examples demonstrating the application potentials of SR-FTIR spectromicroscopy in biomedical research. These will include monitoring living cells progressing through the cell cycle, including death, and cells reacting to dilute concentrations of toxins.« less

Detection of E. coli O157:H7 from ground beef using Fourier transform infrared (FT-IR) spectroscopy and chemometrics.

PubMed

Davis, Reeta; Irudayaraj, Joseph; Reuhs, Bradley L; Mauer, Lisa J

2010-08-01

FT-IR spectroscopy methods for detection, differentiation, and quantification of E. coli O157:H7 strains separated from ground beef were developed. Filtration and immunomagnetic separation (IMS) were used to extract live and dead E. coli O157:H7 cells from contaminated ground beef prior to spectral acquisition. Spectra were analyzed using chemometric techniques in OPUS, TQ Analyst, and WinDAS software programs. Standard plate counts were used for development and validation of spectral analyses. The detection limit based on a selectivity value using the OPUS ident test was 10(5) CFU/g for both Filtration-FT-IR and IMS-FT-IR methods. Experiments using ground beef inoculated with fewer cells (10(1) to 10(2) CFU/g) reached the detection limit at 6 h incubation. Partial least squares (PLS) models with cross validation were used to establish relationships between plate counts and FT-IR spectra. Better PLS predictions were obtained for quantifying live E. coli O157:H7 strains (R(2)> or = 0.9955, RMSEE < or = 0.17, RPD > or = 14) and different ratios of live and dead E. coli O157:H7 cells (R(2)= 0.9945, RMSEE = 2.75, RPD = 13.43) from ground beef using Filtration-FT-IR than IMS-FT-IR methods. Discriminant analysis and canonical variate analysis (CVA) of the spectra differentiated various strains of E. coli O157:H7 from an apathogenic control strain. CVA also separated spectra of 100% dead cells separated from ground beef from spectra of 0.5% live cells in the presence of 99.5% dead cells of E. coli O157:H7. These combined separation and FT-IR methods could be useful for rapid detection and differentiation of pathogens in complex foods.

Generation of drugs coated iron nanoparticles through high energy ball milling

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

Radhika Devi, A.; Murty, B. S.; Chelvane, J. A.

The iron nanoparticles coated with oleic acid and drugs such as folic acid/Amoxicillin were synthesized by high energy ball milling and characterized by X-ray diffraction, Transmission electron microscope, zeta potential, dynamic light scattering, Fourier Transform Infra red (FT-IR) measurements, and thermo gravimetric analysis (TGA). FT-IR and TGA measurements show good adsorption of drugs on oleic acid coated nanoparticles. Magnetic measurements indicate that saturation magnetization is larger for amoxicillin coated particles compared to folic acid coated particles. The biocompatibility of the magnetic nanoparticles prepared was evaluated by in vitro cytotoxicity assay using L929 cells as model cells.

Synthesis and optical properties of polycrystalline Li2Al2B2O7 (LABO)

NASA Astrophysics Data System (ADS)

Dagdale, S. R.; Muley, G. G.

2016-05-01

A polycrystalline lithium aluminum borate (Li2Al2B2O7, LABO) has been synthesized by using simple solid-state technique. The obtained LABO polycrystalline was characterized by powder X-ray diffraction; Fourier transform infrared (FT-IR) spectroscopy and second harmonic generation (SHG) efficiency measurement. The functional groups were identified using the FT-IR spectroscopic data. The SHG efficiency of the polycrystalline material was obtained by the classic Kurtz powder technique using a fundamental wavelength 1064 nm of Nd:YAG laser and it is found to be 1.4 times that of potassium dihydrogen phosphate (KDP).

Opportunities for Live Cell FT-Infrared Imaging: Macromolecule Identification with 2D and 3D Localization

PubMed Central

Mattson, Eric C.; Aboualizadeh, Ebrahim; Barabas, Marie E.; Stucky, Cheryl L.; Hirschmugl, Carol J.

2013-01-01

Infrared (IR) spectromicroscopy, or chemical imaging, is an evolving technique that is poised to make significant contributions in the fields of biology and medicine. Recent developments in sources, detectors, measurement techniques and speciman holders have now made diffraction-limited Fourier transform infrared (FTIR) imaging of cellular chemistry in living cells a reality. The availability of bright, broadband IR sources and large area, pixelated detectors facilitate live cell imaging, which requires rapid measurements using non-destructive probes. In this work, we review advances in the field of FTIR spectromicroscopy that have contributed to live-cell two and three-dimensional IR imaging, and discuss several key examples that highlight the utility of this technique for studying the structure and chemistry of living cells. PMID:24256815

Broadband near-field infrared spectromicroscopy using photothermal probes and synchrotron radiation.

PubMed

Donaldson, Paul M; Kelley, Chris S; Frogley, Mark D; Filik, Jacob; Wehbe, Katia; Cinque, Gianfelice

2016-02-08

In this paper, we experimentally demonstrate the use of infrared synchrotron radiation (IR-SR) as a broadband source for photothermal near-field infrared spectroscopy. We assess two methods of signal transduction; cantilever resonant thermal expansion and scanning thermal microscopy. By means of rapid mechanical chopping (50-150 kHz), we modulate the IR-SR at rates matching the contact resonance frequencies of atomic force microscope (AFM) cantilevers, allowing us to record interferograms yielding Fourier transform infrared (FT-IR) photothermal absorption spectra of polystyrene and cyanoacrylate films. Complementary offline measurements using a mechanically chopped CW IR laser confirmed that the resonant thermal expansion IR-SR measurements were below the diffraction limit, with a spatial resolution better than 500 nm achieved at a wavelength of 6 μm, i.e. λ/12 for the samples studied. Despite achieving the highest signal to noise so far for a scanning thermal microscopy measurement under conditions approaching near-field (dictated by thermal diffusion), the IR-SR resonant photothermal expansion FT-IR spectra measured were significantly higher in signal to noise in comparison with the scanning thermal data.

Rapid Identification and Classification of Listeria spp. and Serotype Assignment of Listeria monocytogenes Using Fourier Transform-Infrared Spectroscopy and Artificial Neural Network Analysis

PubMed Central

Romanolo, K. F.; Gorski, L.; Wang, S.; Lauzon, C. R.

2015-01-01

The use of Fourier Transform-Infrared Spectroscopy (FT-IR) in conjunction with Artificial Neural Network software NeuroDeveloper™ was examined for the rapid identification and classification of Listeria species and serotyping of Listeria monocytogenes. A spectral library was created for 245 strains of Listeria spp. to give a biochemical fingerprint from which identification of unknown samples were made. This technology was able to accurately distinguish the Listeria species with 99.03% accuracy. Eleven serotypes of Listeria monocytogenes including 1/2a, 1/2b, and 4b were identified with 96.58% accuracy. In addition, motile and non-motile forms of Listeria were used to create a more robust model for identification. FT-IR coupled with NeuroDeveloper™ appear to be a more accurate and economic choice for rapid identification of pathogenic Listeria spp. than current methods. PMID:26600423

Analysis of fingerprints features of infrared spectra of various processed products of Rhizoma Coptidis and their different extracts

NASA Astrophysics Data System (ADS)

Xu, Beilei; Zhang, Guijun; Xu, Changhua; Sun, Suqin

2015-09-01

Fourier transform infrared spectroscopy (FT-IR) associated with second derivative infrared spectroscopy (SD-IR) and two-dimensional correlation infrared spectroscopy (2D-IR) are employed to analyze various processed products and different extracts of Rhizoma Coptidis. There is a shift of the peak of 1641 cm-1 of raw Rhizoma Coptidis after processed, which drifts to lower wave number. Peaks at 1508, 1387, 1363, 1332, 1274 and 1234 cm-1 barely change in most samples, except an obvious enhancement of these peaks after processed, suggesting that processed Rhizoma Coptidis may have higher content of berberine than raw material, which is corresponding to the results of correlation coefficients analysis. There are some differences in the absorption peaks in the range of 1800-1000 cm-1 in the SD-IR spectra, which have better resolution, of different processed products. 2D-IR spectra, which elevate the resolution further, can present more differences among the products in the range of 1300-800 cm-1 and 1800-1300 cm-1. Analysis of aqueous, ethanol and petroleum ether extracts of various processed products proves that there are distinctive differences of all auto-peaks in shapes and intensities in all of them. With the advantages of high resolution, high speed and convenience, FT-IR combined with 2D-IR can quickly and precisely distinguish various processed products of Rhizoma Coptidis and can be applied to predict the tendency of transformation of the complicated chemical mixture systems under heat perturbation.

Rapid identification and classification of Listeria spp. and serotype assignment of Listeria monocytogenes using fourier transform-infrared spectroscopy and artificial neural network analysis

USDA-ARS?s Scientific Manuscript database

The use of Fourier Transform-Infrared Spectroscopy (FT-IR) in conjunction with Artificial Neural Network software, NeuroDeveloper™ was examined for the rapid identification and classification of Listeria species and serotyping of Listeria monocytogenes. A spectral library was created for 245 strains...

Proteolytically-induced changes of secondary structural protein conformation of bovine serum albumin monitored by Fourier transform infrared (FT-IR) and UV-circular dichroism spectroscopy

NASA Astrophysics Data System (ADS)

Güler, Günnur; Vorob'ev, Mikhail M.; Vogel, Vitali; Mäntele, Werner

2016-05-01

Enzymatically-induced degradation of bovine serum albumin (BSA) by serine proteases (trypsin and α-chymotrypsin) in various concentrations was monitored by means of Fourier transform infrared (FT-IR) and ultraviolet circular dichroism (UV-CD) spectroscopy. In this study, the applicability of both spectroscopies to monitor the proteolysis process in real time has been proven, by tracking the spectral changes together with secondary structure analysis of BSA as proteolysis proceeds. On the basis of the FTIR spectra and the changes in the amide I band region, we suggest the progression of proteolysis process via conversion of α-helices (1654 cm- 1) into unordered structures and an increase in the concentration of free carboxylates (absorption of 1593 and 1402 cm- 1). For the first time, the correlation between the degree of hydrolysis and the concentration of carboxylic groups measured by FTIR spectroscopy was revealed as well. The far UV-CD spectra together with their secondary structure analysis suggest that the α-helical content decreases concomitant with an increase in the unordered structure. Both spectroscopic techniques also demonstrate that there are similar but less spectral changes of BSA for the trypsin attack than for α-chymotrypsin although the substrate/enzyme ratio is taken the same.

Discrimination of wild-growing and cultivated Lentinus edodes by tri-step infrared spectroscopy

NASA Astrophysics Data System (ADS)

Lin, Haojian; Liu, Gang; Yang, Weimei; An, Ran; Ou, Quanhong

2018-01-01

It's not easy to discriminate dried wild-growing Lentinus edodes (WL) and cultivated Lentinus edodes (CL) by conventional method based on the morphological inspection of fruiting bodies. In this paper, fruiting body samples of WL and CL are discriminated by a tri-step IR spectroscopy method, including Fourier transform infrared (FT-IR) spectroscopy, second derivatives infrared (SD-IR) spectroscopy and two-dimensional correlation infrared (2D-IR) spectroscopy under thermal perturbation. The results show that the FT-IR spectra of WL and CL are similar in holistic spectral profile. More significant differences are exhibited in their SD-IR spectra in the range of 1700 - 900 cm-1. Furthermore, more evident differences have been observed in their synchronous 2D-IR spectra in the range of 2970 - 2900, 1678 - 1390, 1250 -1104 and 1090 - 1030 cm-1. The CL has thirteen auto-peaks at 2958, 2921, 1649, 1563, 1450, 1218, 1192, 1161, 1140, 1110, 1082, 1065 and 1047 cm-1, in which the four strongest auto-peaks are at 2921, 1563, 1192 and 1082 cm-1. The WL shows fifteen auto-peaks at 2960, 2937, 2921, 1650, 1615, 1555, 1458, 1219, 1190, 1138, 1111, 1084, 1068, 1048 and 1033 cm-1, in which the four strongest auto-peaks are at 2921, 1650, 1190 and 1068 cm-1. This study shows the potential of FT-IR spectroscopy and 2D correlation analysis in a simple and quick distinction of wild-growing and cultivated mushrooms.

T-dependence of the vibrational dynamics of IBP/diME-β-CD in solid state: A FT-IR spectral and quantum chemical study

NASA Astrophysics Data System (ADS)

Crupi, V.; Guella, G.; Majolino, D.; Mancini, I.; Rossi, B.; Stancanelli, R.; Venuti, V.; Verrocchio, P.; Viliani, G.

2010-05-01

Solid inclusion complex of the non-steroidal anti-inflammatory drug Ibuprofen (IBP, (2-[4-(2-methylpropyl)phenyl]-propanoic acid) with (2,6-dimethyl)-β-cyclodextrin (diME-β-CD) has been investigated by Fourier transform infrared spectroscopy in attenuated total reflectance geometry (FTIR-ATR spectroscopy) and numerical simulation. The complexation-induced changes in the FTIR-ATR spectrum of IBP have been interpreted by comparison with the theoretical vibrational wavenumbers and IR intensities of dimeric structures of IBP, derived from symmetric hydrogen bonding of the two carboxylic groups, computed by using Density Functional Theory (DFT) calculations. From temperature-dependent studies, the enthalpy change ΔH associated with the binding of IBP with diME-β-CD for 1:1 stoichiometry, in solid phase, has been estimated.

Identification of the traditional Tibetan medicine "Shaji" and their different extracts through tri-step infrared spectroscopy

NASA Astrophysics Data System (ADS)

Liu, Yue; Li, Jingyi; Fan, Gang; Sun, Suqin; Zhang, Yuxin; Zhang, Yi; Tu, Ya

2016-11-01

Hippophae rhamnoides subsp. sinensis Rousi, Hippophae gyantsensis (Rousi) Y. S. Lian, Hippophae neurocarpa S. W. Liu & T. N. He and Hippophae tibetana Schlechtendal are typically used under one name "Shaji", to treat cardiovascular diseases and lung disorders in Tibetan medicine (TM). A complete set of infrared (IR) macro-fingerprints of these four Hippophae species should be characterized and compared simply, accurately, and in detail for identification. In the present study, tri-step IR spectroscopy, which included Fourier transform IR (FT-IR) spectroscopy, second derivative IR (SD-IR) spectroscopy and two-dimensional correlation IR (2D-IR) spectroscopy, was employed to discriminate the four Hippophae species and their corresponding extracts using different solvents. The relevant spectra exhibited the holistic chemical compositions and variations. Flavonoids, fatty acids and sugars were found to be the main chemical components. Characteristic peak positions, intensities and shapes derived from FT-IR, SD-IR and 2D-IR spectra provided valuable information for sample discrimination. Principal component analysis (PCA) of spectral differences was performed to illustrate the objective identification. Results showed that the species and their extracts can be clearly distinguished. Thus, a quick, precise and effective tri-step IR spectroscopy combined with PCA can be applied to identify and discriminate medicinal materials and their extracts in TM research.

Fourier Transform Infrared (FT-IR) Spectroscopy of Atmospheric Trace Gases HCl, NO and SO2

NASA Technical Reports Server (NTRS)

Haridass, C.; Aw-Musse, A.; Dowdye, E.; Bandyopadhyay, C.; Misra, P.; Okabe, H.

1998-01-01

Fourier Transform Infrared (FT-IR) spectral data have been recorded in the spectral region 400-4000/cm of hydrogen chloride and sulfur dioxide with I/cm resolution and of nitric oxide with 0.25 cm-i resolution, under quasi-static conditions, when the sample gas was passed through tubings of aluminum, copper, stainless steel and teflon. The absorbance was measured for the rotational lines of the fundamental bands of (1)H(35)Cl and (1)H(37)Cl for pressures in the range 100-1000 Torr and for the (14)N(16)O molecule in the range 100-300 Torr. The absorbance was also measured for individual rotational lines corresponding to the three modes of vibrations (upsilon(sub 1) - symmetric stretch, upsilon(sub 2) - symmetric bend, upsilon(sub 3) - anti-symmetric stretch) of the SO2 molecule in the pressure range 25-150 Torr. A graph of absorbance versus pressure was plotted for the observed rotational transitions of the three atmospherically significant molecules, and it was found that the absorbance was linearly proportional to the pressure range chosen, thereby validating Beer's law. The absorption cross-sections were determined from the graphical slopes for each rotational transition recorded for the HCl, NO and SO2 species. Qualitative and quantitative spectral changes in the FT-IR data will be discussed to identify and characterize various tubing materials with respect to their absorption features.

High-Throughput Metabolic Fingerprinting of Legume Silage Fermentations via Fourier Transform Infrared Spectroscopy and Chemometrics

PubMed Central

Johnson, Helen E.; Broadhurst, David; Kell, Douglas B.; Theodorou, Michael K.; Merry, Roger J.; Griffith, Gareth W.

2004-01-01

Silage quality is typically assessed by the measurement of several individual parameters, including pH, lactic acid, acetic acid, bacterial numbers, and protein content. The objective of this study was to use a holistic metabolic fingerprinting approach, combining a high-throughput microtiter plate-based fermentation system with Fourier transform infrared (FT-IR) spectroscopy, to obtain a snapshot of the sample metabolome (typically low-molecular-weight compounds) at a given time. The aim was to study the dynamics of red clover or grass silage fermentations in response to various inoculants incorporating lactic acid bacteria (LAB). The hyperspectral multivariate datasets generated by FT-IR spectroscopy are difficult to interpret visually, so chemometrics methods were used to deconvolute the data. Two-phase principal component-discriminant function analysis allowed discrimination between herbage types and different LAB inoculants and modeling of fermentation dynamics over time. Further analysis of FT-IR spectra by the use of genetic algorithms to identify the underlying biochemical differences between treatments revealed that the amide I and amide II regions (wavenumbers of 1,550 to 1,750 cm−1) of the spectra were most frequently selected (reflecting changes in proteins and free amino acids) in comparisons between control and inoculant-treated fermentations. This corresponds to the known importance of rapid fermentation for the efficient conservation of forage proteins. PMID:15006782

Fast Fourier Transform IR Characterization of Epoxy GY Systems Crosslinked with Aliphatic and Cycloaliphatic EH Polyamine Adducts

PubMed Central

Nikolic, Goran; Zlatkovic, Sasa; Cakic, Milorad; Cakic, Suzana; Lacnjevac, Caslav; Rajic, Zoran

2010-01-01

The use of fast FT-IR spectroscopy as a sensitive method to estimate a change of the crosslinking kinetics of epoxy resin with polyamine adducts is described in this study. A new epoxy formulation based on the use of polyamine adducts as the hardeners was analyzed. Crosslinking reactions of the different stoichiometric mixtures of the unmodified GY250 epoxy resin with the aliphatic EH606 and the cycloaliphatic EH637 polyamine adducts were studied using mid FT-IR spectroscopic techniques. As the crosslinking proceeded, the primary amine groups in polyamine adduct are converted to secondary and the tertiary amines. The decrease in the IR band intensity of epoxy groups at about 915 cm−1, as well as at about 3,056 cm−1, was observed due to process. Mid IR spectral analysis was used to calculate the content of the epoxy groups as a function of crosslinking time and the crosslinking degree of resin. The amount of all the epoxy species was estimated from IR spectra to changes during the crosslinking kinetics of epichlorhydrin. PMID:22315562

Toward the characterization of biological toxins using field-based FT-IR spectroscopic instrumentation

NASA Astrophysics Data System (ADS)

Schiering, David W.; Walton, Robert B.; Brown, Christopher W.; Norman, Mark L.; Brewer, Joseph; Scott, James

2004-12-01

IR spectroscopy is a broadly applicable technique for the identification of covalent materials. Recent advances in instrumentation have made Fourier Transform infrared (FT-IR) spectroscopy available for field characterization of suspect materials. Presently, this instrumentation is broadly deployed and used for the identification of potential chemical hazards. This discussion concerns work towards expanding the analytical utility of field-based FT-IR spectrometry in the characterization of biological threats. Two classes of materials were studied: biologically produced chemical toxins which were non-peptide in nature and peptide toxin. The IR spectroscopic identification of aflatoxin-B1, trichothecene T2 mycotoxin, and strychnine was evaluated using the approach of spectral searching against large libraries of materials. For pure components, the IR method discriminated the above toxins at better than the 99% confidence level. The ability to identify non-peptide toxins in mixtures was also evaluated using a "spectral stripping" search approach. For the mixtures evaluated, this method was able to identify the mixture components from ca. 32K spectral library entries. Castor bean extract containing ricin was used as a representative peptide toxin. Due to similarity in protein spectra, a SIMCA pattern recognition methodology was evaluated for classifying peptide toxins. In addition to castor bean extract the method was validated using bovine serum albumin and myoglobin as simulants. The SIMCA approach was successful in correctly classifying these samples at the 95% confidence level.

Application of Fourier transform infrared (FT-IR) spectroscopy to the study of the modification of epoxidized sunflower oil by acrylation.

PubMed

Irinislimane, Ratiba; Belhaneche-Bensemra, Naima

2012-12-01

Commercial sunflower oil was epoxidized at the laboratory-scale. The epoxidized sunflower oil (ESFO) was modified following the acrylation reaction. Modification was carried out simultaneously using acrylic acid (AA) and triethylamine (TEA). To optimize the reaction conditions, the effects of four temperatures (40, 60, 80, and 100 °C), the ESFO:AA (100:100) ratio, and 0.2% TEA were investigated. The rate of conversion was analyzed with both FT-IR and titration of the oxirane ring. After that, the temperature with the highest conversion was selected and used throughout for all modification reactions. Then, four ratios (100:100, 100:90, 100:80, and 100:75) of ESFO:AA were analyzed at four different concentrations of TEA (0.2, 0.3, 0.4, and 0.5%) to determine the best estimate for both the ESFO:AA ratio and the catalyst concentration. Conversion rate was analyzed using FT-IR spectroscopy by measuring the concentrations of ester, carbonyl, and alcohol groups. Moreover, oxirane-ring concentration was estimated using the titration method (with gentian violet as indicator) and FT-IR spectroscopy (epoxy ring absorptions at 1270 cm(-1) and 877 cm(-1)). Based on conversion yield, the optimum ESFO:AA ratio corresponds to 100:80; the best temperature reaction was at 60 °C, and the best TEA concentration was 0.2%. The critical amounts of reactants needed to reach maximum conversion were established. The final acid value of the acrylated ESFO after washing (pH = 7) was 2.1 mg potassium hydroxide (KOH)·g(-1). All results show that FT-IR spectroscopy is a simple, low-cost, rapid method for investigating the kinetics of a reaction.

Geographic identification of Boletus mushrooms by data fusion of FT-IR and UV spectroscopies combined with multivariate statistical analysis

NASA Astrophysics Data System (ADS)

Yao, Sen; Li, Tao; Li, JieQing; Liu, HongGao; Wang, YuanZhong

2018-06-01

Boletus griseus and Boletus edulis are two well-known wild-grown edible mushrooms which have high nutrition, delicious flavor and high economic value distributing in Yunnan Province. In this study, a rapid method using Fourier transform infrared (FT-IR) and ultraviolet (UV) spectroscopies coupled with data fusion was established for the discrimination of Boletus mushrooms from seven different geographical origins with pattern recognition method. Initially, the spectra of 332 mushroom samples obtained from the two spectroscopic techniques were analyzed individually and then the classification performance based on data fusion strategy was investigated. Meanwhile, the latent variables (LVs) of FT-IR and UV spectra were extracted by partial least square discriminant analysis (PLS-DA) and two datasets were concatenated into a new matrix for data fusion. Then, the fusion matrix was further analyzed by support vector machine (SVM). Compared with single spectroscopic technique, data fusion strategy can improve the classification performance effectively. In particular, the accuracy of correct classification of SVM model in training and test sets were 99.10% and 100.00%, respectively. The results demonstrated that data fusion of FT-IR and UV spectra can provide higher synergic effect for the discrimination of different geographical origins of Boletus mushrooms, which may be benefit for further authentication and quality assessment of edible mushrooms.

Differentiation and identification of grape-associated black aspergilli using Fourier transform infrared (FT-IR) spectroscopic analysis of mycelia.

PubMed

Kogkaki, Efstathia A; Sofoulis, Manos; Natskoulis, Pantelis; Tarantilis, Petros A; Pappas, Christos S; Panagou, Efstathios Z

2017-10-16

The purpose of this study was to evaluate the potential of FT-IR spectroscopy as a high-throughput method for rapid differentiation among the ochratoxigenic species of Aspergillus carbonarius and the non-ochratoxigenic or low toxigenic species of Aspergillus niger aggregate, namely A. tubingensis and A. niger isolated previously from grapes of Greek vineyards. A total of 182 isolates of A. carbonarius, A. tubingensis, and A. niger were analyzed using FT-IR spectroscopy. The first derivative of specific spectral regions (3002-2801cm -1 , 1773-1550cm -1 , and 1286-952cm -1 ) were chosen and evaluated with respect to absorbance values. The average spectra of 130 fungal isolates were used for model calibration based on Discriminant analysis and the remaining 52 spectra were used for external model validation. This methodology was able to differentiate correctly 98.8% in total accuracy in both model calibration and validation. The per class accuracy for A. carbonarius was 95.3% and 100% for model calibration and validation, respectively, whereas for A. niger aggregate the per class accuracy amounted to 100% in both cases. The obtained results indicated that FT-IR could become a promising, fast, reliable and low-cost tool for the discrimination and differentiation of closely related fungal species. Copyright © 2017 Elsevier B.V. All rights reserved.

Geographic identification of Boletus mushrooms by data fusion of FT-IR and UV spectroscopies combined with multivariate statistical analysis.

PubMed

Yao, Sen; Li, Tao; Li, JieQing; Liu, HongGao; Wang, YuanZhong

2018-06-05

Boletus griseus and Boletus edulis are two well-known wild-grown edible mushrooms which have high nutrition, delicious flavor and high economic value distributing in Yunnan Province. In this study, a rapid method using Fourier transform infrared (FT-IR) and ultraviolet (UV) spectroscopies coupled with data fusion was established for the discrimination of Boletus mushrooms from seven different geographical origins with pattern recognition method. Initially, the spectra of 332 mushroom samples obtained from the two spectroscopic techniques were analyzed individually and then the classification performance based on data fusion strategy was investigated. Meanwhile, the latent variables (LVs) of FT-IR and UV spectra were extracted by partial least square discriminant analysis (PLS-DA) and two datasets were concatenated into a new matrix for data fusion. Then, the fusion matrix was further analyzed by support vector machine (SVM). Compared with single spectroscopic technique, data fusion strategy can improve the classification performance effectively. In particular, the accuracy of correct classification of SVM model in training and test sets were 99.10% and 100.00%, respectively. The results demonstrated that data fusion of FT-IR and UV spectra can provide higher synergic effect for the discrimination of different geographical origins of Boletus mushrooms, which may be benefit for further authentication and quality assessment of edible mushrooms. Copyright © 2018 Elsevier B.V. All rights reserved.

Determination of diosmin in pharmaceutical formulations using Fourier transform infrared spectrophotometry

PubMed Central

Bunaciu, Andrei A.; Udristioiu, Gabriela Elena; Ruţă, Lavinia L.; Fleschin, Şerban; Aboul-Enein, Hassan Y.

2009-01-01

A Fourier transform infrared (FT-IR) spectrometric method was developed for the rapid, direct measurement of diosmin in different pharmaceutical drugs. Conventional KBr-spectra were compared for best determination of active substance in commercial preparations. The Beer–Lambert law and two chemometric approaches, partial least squares (PLS) and principal component regression (PCR+) methods, were tried in data processing. PMID:23960715

Sample and data processing considerations for the NIST quantitative infrared database

NASA Astrophysics Data System (ADS)

Chu, Pamela M.; Guenther, Franklin R.; Rhoderick, George C.; Lafferty, Walter J.; Phillips, William

1999-02-01

Fourier-transform infrared (FT-IR) spectrometry has become a useful real-time in situ analytical technique for quantitative gas phase measurements. In fact, the U.S. Environmental Protection Agency (EPA) has recently approved open-path FT-IR monitoring for the determination of hazardous air pollutants (HAP) identified in EPA's Clean Air Act of 1990. To support infrared based sensing technologies, the National Institute of Standards and Technology (NIST) is currently developing a standard quantitative spectral database of the HAPs based on gravimetrically prepared standard samples. The procedures developed to ensure the quantitative accuracy of the reference data are discussed, including sample preparation, residual sample contaminants, data processing considerations, and estimates of error.

Preparation of hydroxyapatite from animal bones.

PubMed

Sobczak, Agnieszka; Kowalski, Zygmunt; Wzorek, Zbigniew

2009-01-01

This paper presents the method of obtaining hydroxyapatite from animal bones. Bone sludge and calcined products were characterized by X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Calcium concentration was determined with titration, and phosphorus--spectrophotometrically. Making use of the AAS and ICP methods the content of microelements was determined. In all the products, hydroxyapatite was the only crystalline phase indicated. The FT-IR spectra confirmed that calcination removed the total of organic substances. Calcium and phosphorus contents were 38% and 18%, respectively, which corresponded to the Ca/P molar ratio of nonstoichiometric hydroxyapatite. The specific surfaces of products were measured by BET method. The volume of micro- and mesopores was determined.

Fourier Transform Infrared Spectroscopy Part III. Applications.

ERIC Educational Resources Information Center

Perkins, W. D.

1987-01-01

Discusses the use of the FT-IR spectrometer in analyses that were previously avoided. Examines some of the applications of this spectroscopy with aqueous solutions, circular internal reflection, samples with low transmission, diffuse reflectance, infrared emission, and the infrared microscope. (TW)

The characterization of hydroxypropyl methylcellulose through the analysis of its substituents

USDA-ARS?s Scientific Manuscript database

The methyl and hydroxypropyl substituents in hydroxypropyl methylcellulose (HPMC) affect the resulting gel properties. These substituents in five HPMC gels were characterized using Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, small-amplitude oscillatory shear measurements, a...

Flow-through Fourier transform infrared sensor for total hydrocarbons determination in water.

PubMed

Pérez-Palacios, David; Armenta, Sergio; Lendl, Bernhard

2009-09-01

A new flow-through Fourier transform infrared (FT-IR) sensor for oil in water analysis based on solid-phase spectroscopy on octadecyl (C18) silica particles has been developed. The C18 non-polar sorbent is placed inside the sensor and is able to retain hydrocarbons from water samples. The system does not require the use of chlorinated solvents, reducing the environmental impact, and the minimal sample handling stages serve to ensure sample integrity whilst reducing exposure of the analyst to any toxic hydrocarbons present within the samples. Fourier transform infrared (FT-IR) spectra were recorded by co-adding 32 scans at a resolution of 4 cm(-1) and the band located at 1462 cm(-1) due to the CH(2) bending was integrated from 1475 to 1450 cm(-1) using a baseline correction established between 1485 and 1440 cm(-1) using the areas as analytical signal. The technique, which provides a limit of detection (LOD) of 22 mg L(-1) and a precision expressed as relative standard deviation (RSD) lower than 5%, is considerably rapid and allows for a high level of automation.

Analysis and identification of two similar traditional Chinese medicines by using a three-stage infrared spectroscopy: Ligusticum chuanxiong, Angelica sinensis and their different extracts

NASA Astrophysics Data System (ADS)

Xiang, Li; Wang, Jingjuan; Zhang, Guijun; Rong, Lixin; Wu, Haozhong; Sun, Suqin; Guo, Yizhen; Yang, Yanfang; Lu, Lina; Qu, Lei

2016-11-01

Rhizoma Chuanxiong (CX) and Radix Angelica sinensis (DG) are very important Traditional Chinese Medicine (TCM) and usually used in clinic. They both are from the Umbelliferae family, and have almost similar chemical constituents with each other. It is complicated, time-consuming and laborious to discriminate them by using the chromatographic methods such as high performance liquid chromatography (HPLC) and gas chromatography (GC). Therefore, to find a fast, applicable and effective identification method for two herbs is urged in quality research of TCM. In this paper, by using a three-stage infrared spectroscopy (Fourier transform infrared spectroscopy (FT-IR), the second derivative infrared spectroscopy (SD-IR) and two-dimensional correlation infrared spectroscopy (2D-IR)), we analyzed and discriminated CX, DG and their different extracts (aqueous extract, alcoholic extract and petroleum ether extract). In FT-IR, all the CX and DG samples' spectra seemed similar, but they had their own unique macroscopic fingerprints to identify. Through comparing with the spectra of sucrose and the similarity calculation, we found the content of sucrose in DG raw materials was higher than in CX raw materials. The significant differences in alcoholic extract appeared that in CX alcoholic extract, the peaks at 1743 cm-1 was obviously stronger than the peak at same position in DG alcoholic extract. Besides in petroleum ether extract, we concluded CX contained much more ligustilide than DG by the similarity calculation. With the function of SD-IR, some tiny differences were amplified and overlapped peaks were also unfolded in FT-IR. In the range of 1100-1175 cm-1, there were six peaks in the SD-IR spectra of DG and the intensity, shape and location of those six peaks were similar to that of sucrose, while only two peaks could be observed in that of CX and those two peaks were totally different from sucrose in shape and relative intensity. This result was consistent with that of the FT-IR. Several undetected characteristic fingerprints in FT-IR and SD-IR spectra were further disclosed by 2D-IR spectra. In the range of 1120-1500 cm-1, the FT-IR spectra and the SD-IR spectra of aqueous extract of CX and DG were almost similar and hard to be discriminated, but the 2D-IR spectra were markedly different. These findings indicated that the three-stage infrared spectroscopy can identify not only the main compositions in these two medicinal materials and their different extracts, but also can compare the differences of categories and quantities of chemical constituents between the similar samples. In conclusion, the three-stage infrared spectroscopy could identify the two similar TCM (CX and DG) quickly and effectively.

Wide-field FTIR microscopy using mid-IR pulse shaping

PubMed Central

Serrano, Arnaldo L.; Ghosh, Ayanjeet; Ostrander, Joshua S.; Zanni, Martin T.

2015-01-01

We have developed a new table-top technique for collecting wide-field Fourier transform infrared (FTIR) microscopic images by combining a femtosecond pulse shaper with a mid-IR focal plane array. The pulse shaper scans the delay between a pulse pair extremely rapidly for high signal-to-noise, while also enabling phase control of the individual pulses to under-sample the interferograms and subtract background. Infrared absorption images were collected for a mixture of W(CO)6 or Mn2(CO)10 absorbed polystyrene beads, demonstrating that this technique can spatially resolve chemically distinct species. The images are sub-diffraction limited, as measured with a USAF test target patterned on CaF2 and verified with scalar wave simulations. We also find that refractive, rather than reflective, objectives are preferable for imaging with coherent radiation. We discuss this method with respect to conventional FTIR microscopes. PMID:26191843

The existence of imidazoline corrosion inhibitors

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

Martin, J.A.; Valone, F.W.

1985-05-01

Spectroscopic methods, i.e., Fourier transform infrared (FT-IR), carbon-13 nuclear magnetic reasonance (/sup 13/C NMR), and ultraviolet (UV) spectroscopy, were used to investigate the actual chemical composition of oilfield corrosion inhibitors. Inhibitor formulations consisting of an amide or imidazoline reacted with a dimer-trimer acid, along with an ethoxylated surfactant and an aromatic solvent, were used for these studies. /sup 13/C NMR and FT-IR spectra of these inhibitors, as well as spectra of pure imidazolines, showed that the imidazoline functional group was fairly rapidly hydrolyzed to the amide form. For instance, in FT-IR studies, the imine functional group decreased in intensity asmore » a function of time. Coincident with this was an increase in the intensities of the vibrational resonances attributed to the amide functionality. The relative molar ratio of imidazoline to amide in a corrosion inhibitor could be calculated via UV spectroscopy. Within a 20 day interval after inhibitor synthesis, this ratio decreased by a factor greater than 20. These results, as well as a discussion of their economic impact on oilfield corrosion inhibitor formulation, are presented in this paper.« less

Fast Infrared Chemical Imaging with a Quantum Cascade Laser

PubMed Central

2015-01-01

Infrared (IR) spectroscopic imaging systems are a powerful tool for visualizing molecular microstructure of a sample without the need for dyes or stains. Table-top Fourier transform infrared (FT-IR) imaging spectrometers, the current established technology, can record broadband spectral data efficiently but requires scanning the entire spectrum with a low throughput source. The advent of high-intensity, broadly tunable quantum cascade lasers (QCL) has now accelerated IR imaging but results in a fundamentally different type of instrument and approach, namely, discrete frequency IR (DF-IR) spectral imaging. While the higher intensity of the source provides a higher signal per channel, the absence of spectral multiplexing also provides new opportunities and challenges. Here, we couple a rapidly tunable QCL with a high performance microscope equipped with a cooled focal plane array (FPA) detector. Our optical system is conceptualized to provide optimal performance based on recent theory and design rules for high-definition (HD) IR imaging. Multiple QCL units are multiplexed together to provide spectral coverage across the fingerprint region (776.9 to 1904.4 cm–1) in our DF-IR microscope capable of broad spectral coverage, wide-field detection, and diffraction-limited spectral imaging. We demonstrate that the spectral and spatial fidelity of this system is at least as good as the best FT-IR imaging systems. Our configuration provides a speedup for equivalent spectral signal-to-noise ratio (SNR) compared to the best spectral quality from a high-performance linear array system that has 10-fold larger pixels. Compared to the fastest available HD FT-IR imaging system, we demonstrate scanning of large tissue microarrays (TMA) in 3-orders of magnitude smaller time per essential spectral frequency. These advances offer new opportunities for high throughput IR chemical imaging, especially for the measurement of cells and tissues. PMID:25474546

Fast infrared chemical imaging with a quantum cascade laser.

PubMed

Yeh, Kevin; Kenkel, Seth; Liu, Jui-Nung; Bhargava, Rohit

2015-01-06

Infrared (IR) spectroscopic imaging systems are a powerful tool for visualizing molecular microstructure of a sample without the need for dyes or stains. Table-top Fourier transform infrared (FT-IR) imaging spectrometers, the current established technology, can record broadband spectral data efficiently but requires scanning the entire spectrum with a low throughput source. The advent of high-intensity, broadly tunable quantum cascade lasers (QCL) has now accelerated IR imaging but results in a fundamentally different type of instrument and approach, namely, discrete frequency IR (DF-IR) spectral imaging. While the higher intensity of the source provides a higher signal per channel, the absence of spectral multiplexing also provides new opportunities and challenges. Here, we couple a rapidly tunable QCL with a high performance microscope equipped with a cooled focal plane array (FPA) detector. Our optical system is conceptualized to provide optimal performance based on recent theory and design rules for high-definition (HD) IR imaging. Multiple QCL units are multiplexed together to provide spectral coverage across the fingerprint region (776.9 to 1904.4 cm(-1)) in our DF-IR microscope capable of broad spectral coverage, wide-field detection, and diffraction-limited spectral imaging. We demonstrate that the spectral and spatial fidelity of this system is at least as good as the best FT-IR imaging systems. Our configuration provides a speedup for equivalent spectral signal-to-noise ratio (SNR) compared to the best spectral quality from a high-performance linear array system that has 10-fold larger pixels. Compared to the fastest available HD FT-IR imaging system, we demonstrate scanning of large tissue microarrays (TMA) in 3-orders of magnitude smaller time per essential spectral frequency. These advances offer new opportunities for high throughput IR chemical imaging, especially for the measurement of cells and tissues.

Fingerprinting profile of polysaccharides from Lycium barbarum using multiplex approaches and chemometrics

USDA-ARS?s Scientific Manuscript database

Techniques including ultraviolet-visible spectra (UV), high performance size-exclusion chromatography (HPSEC), fourier-transform infrared spectroscopy (FT-IR) and pre-column derivatization high-performance liquid chromatography (PCD-HPLC) were used in the fingerprinting analysis of Lycium barbarum p...

Comparison between infrared and Raman spectroscopic analysis of maturing rabbit cortical bone.

PubMed

Turunen, Mikael J; Saarakkala, Simo; Rieppo, Lassi; Helminen, Heikki J; Jurvelin, Jukka S; Isaksson, Hanna

2011-06-01

The molecular composition of the organic and inorganic matrices of bone undergoes alterations during maturation. The aim of this study was to compare Fourier transform infrared (FT-IR) and near-infrared (NIR) Raman microspectroscopy techniques for characterization of the composition of growing and developing bone from young to skeletally mature rabbits. Moreover, the specificity and differences of the techniques for determining bone composition were clarified. The humeri of female New Zealand White rabbits, with age range from young to skeletally mature animals (four age groups, n = 7 per group), were studied. Spectral peak areas, intensities, and ratios related to organic and inorganic matrices of bone were analyzed and compared between the age groups and between FT-IR and Raman microspectroscopic techniques. Specifically, the degree of mineralization, type-B carbonate substitution, crystallinity of hydroxyapatite (HA), mineral content, and collagen maturity were examined. Significant changes during maturation were observed in various compositional parameters with one or both techniques. Overall, the compositional parameters calculated from the Raman spectra correlated with analogous parameters calculated from the IR spectra. Collagen cross-linking (XLR), as determined through peak fitting and directly from the IR spectra, were highly correlated. The mineral/matrix ratio in the Raman spectra was evaluated with multiple different peaks representing the organic matrix. The results showed high correlation with each other. After comparison with the bone mineral density (BMD) values from micro-computed tomography (micro-CT) imaging measurements and crystal size from XRD measurements, it is suggested that Raman microspectroscopy is more sensitive than FT-IR microspectroscopy for the inorganic matrix of the bone. In the literature, similar spectroscopic parameters obtained with FT-IR and NIR Raman microspectroscopic techniques are often compared. According to the present results, however, caution is required when performing this kind of comparison.

Predicting ambient aerosol Thermal Optical Reflectance (TOR) measurements from infrared spectra: organic carbon

NASA Astrophysics Data System (ADS)

Dillner, A. M.; Takahama, S.

2014-11-01

Organic carbon (OC) can constitute 50% or more of the mass of atmospheric particulate matter. Typically, the organic carbon concentration is measured using thermal methods such as Thermal-Optical Reflectance (TOR) from quartz fiber filters. Here, methods are presented whereby Fourier Transform Infrared (FT-IR) absorbance spectra from polytetrafluoroethylene (PTFE or Teflon) filters are used to accurately predict TOR OC. Transmittance FT-IR analysis is rapid, inexpensive, and non-destructive to the PTFE filters. To develop and test the method, FT-IR absorbance spectra are obtained from 794 samples from seven Interagency Monitoring of PROtected Visual Environment (IMPROVE) sites sampled during 2011. Partial least squares regression is used to calibrate sample FT-IR absorbance spectra to artifact-corrected TOR OC. The FTIR spectra are divided into calibration and test sets by sampling site and date which leads to precise and accurate OC predictions by FT-IR as indicated by high coefficient of determination (R2; 0.96), low bias (0.02 μg m-3, all μg m-3 values based on the nominal IMPROVE sample volume of 32.8 m-3), low error (0.08 μg m-3) and low normalized error (11%). These performance metrics can be achieved with various degrees of spectral pretreatment (e.g., including or excluding substrate contributions to the absorbances) and are comparable in precision and accuracy to collocated TOR measurements. FT-IR spectra are also divided into calibration and test sets by OC mass and by OM / OC which reflects the organic composition of the particulate matter and is obtained from organic functional group composition; this division also leads to precise and accurate OC predictions. Low OC concentrations have higher bias and normalized error due to TOR analytical errors and artifact correction errors, not due to the range of OC mass of the samples in the calibration set. However, samples with low OC mass can be used to predict samples with high OC mass indicating that the calibration is linear. Using samples in the calibration set that have a different OM / OC or ammonium / OC distributions than the test set leads to only a modest increase in bias and normalized error in the predicted samples. We conclude that FT-IR analysis with partial least squares regression is a robust method for accurately predicting TOR OC in IMPROVE network samples; providing complementary information to the organic functional group composition and organic aerosol mass estimated previously from the same set of sample spectra (Ruthenburg et al., 2014).

Predicting ambient aerosol thermal-optical reflectance measurements from infrared spectra: elemental carbon

NASA Astrophysics Data System (ADS)

Dillner, A. M.; Takahama, S.

2015-10-01

Elemental carbon (EC) is an important constituent of atmospheric particulate matter because it absorbs solar radiation influencing climate and visibility and it adversely affects human health. The EC measured by thermal methods such as thermal-optical reflectance (TOR) is operationally defined as the carbon that volatilizes from quartz filter samples at elevated temperatures in the presence of oxygen. Here, methods are presented to accurately predict TOR EC using Fourier transform infrared (FT-IR) absorbance spectra from atmospheric particulate matter collected on polytetrafluoroethylene (PTFE or Teflon) filters. This method is similar to the procedure developed for OC in prior work (Dillner and Takahama, 2015). Transmittance FT-IR analysis is rapid, inexpensive and nondestructive to the PTFE filter samples which are routinely collected for mass and elemental analysis in monitoring networks. FT-IR absorbance spectra are obtained from 794 filter samples from seven Interagency Monitoring of PROtected Visual Environment (IMPROVE) sites collected during 2011. Partial least squares regression is used to calibrate sample FT-IR absorbance spectra to collocated TOR EC measurements. The FT-IR spectra are divided into calibration and test sets. Two calibrations are developed: one developed from uniform distribution of samples across the EC mass range (Uniform EC) and one developed from a uniform distribution of Low EC mass samples (EC < 2.4 μg, Low Uniform EC). A hybrid approach which applies the Low EC calibration to Low EC samples and the Uniform EC calibration to all other samples is used to produce predictions for Low EC samples that have mean error on par with parallel TOR EC samples in the same mass range and an estimate of the minimum detection limit (MDL) that is on par with TOR EC MDL. For all samples, this hybrid approach leads to precise and accurate TOR EC predictions by FT-IR as indicated by high coefficient of determination (R2; 0.96), no bias (0.00 μg m-3, a concentration value based on the nominal IMPROVE sample volume of 32.8 m3), low error (0.03 μg m-3) and reasonable normalized error (21 %). These performance metrics can be achieved with various degrees of spectral pretreatment (e.g., including or excluding substrate contributions to the absorbances) and are comparable in precision and accuracy to collocated TOR measurements. Only the normalized error is higher for the FT-IR EC measurements than for collocated TOR. FT-IR spectra are also divided into calibration and test sets by the ratios OC/EC and ammonium/EC to determine the impact of OC and ammonium on EC prediction. We conclude that FT-IR analysis with partial least squares regression is a robust method for accurately predicting TOR EC in IMPROVE network samples, providing complementary information to TOR OC predictions (Dillner and Takahama, 2015) and the organic functional group composition and organic matter estimated previously from the same set of sample spectra (Ruthenburg et al., 2014).

Application of FT-IR spectroscopy on breast cancer serum analysis

NASA Astrophysics Data System (ADS)

Elmi, Fatemeh; Movaghar, Afshin Fayyaz; Elmi, Maryam Mitra; Alinezhad, Heshmatollah; Nikbakhsh, Novin

2017-12-01

Breast cancer is regarded as the most malignant tumor among women throughout the world. Therefore, early detection and proper diagnostic methods have been known to help save women's lives. Fourier Transform Infrared (FT-IR) spectroscopy, coupled with PCA-LDA analysis, is a new technique to investigate the characteristics of serum in breast cancer. In this study, 43 breast cancer and 43 healthy serum samples were collected, and the FT-IR spectra were recorded for each one. Then, PCA analysis and linear discriminant analysis (LDA) were used to analyze the spectral data. The results showed that there were differences between the spectra of the two groups. Discriminating wavenumbers were associated with several spectral differences over the 950-1200 cm- 1(sugar), 1190-1350 cm- 1 (collagen), 1475-1710 cm- 1 (protein), 1710-1760 cm- 1 (ester), 2800-3000 cm- 1 (stretching motions of -CH2 & -CH3), and 3090-3700 cm- 1 (NH stretching) regions. PCA-LDA performance on serum IR could recognize changes between the control and the breast cancer cases. The diagnostic accuracy, sensitivity, and specificity of PCA-LDA analysis for 3000-3600 cm- 1 (NH stretching) were found to be 83%, 84%, 74% for the control and 80%, 76%, 72% for the breast cancer cases, respectively. The results showed that the major spectral differences between the two groups were related to the differences in protein conformation in serum samples. It can be concluded that FT-IR spectroscopy, together with multivariate data analysis, is able to discriminate between breast cancer and healthy serum samples.

Kinetics and evolved gas analysis for pyrolysis of food processing wastes using TGA/MS/FT-IR.

PubMed

Özsin, Gamzenur; Pütün, Ayşe Eren

2017-06-01

The objective of this study was to identify the pyrolysis of different bio-waste produced by food processing industry in a comprehensible manner. For this purpose, pyrolysis behaviors of chestnut shells (CNS), cherry stones (CS) and grape seeds (GS) were investigated by thermogravimetric analysis (TGA) combined with a Fourier-transform infrared (FT-IR) spectrometer and a mass spectrometer (MS). In order to make available theoretical groundwork for biomass pyrolysis, activation energies were calculated with the help of four different model-free kinetic methods. The results are attributed to the complex reaction schemes which imply parallel, competitive and complex reactions during pyrolysis. During pyrolysis, the evolution of volatiles was also characterized by FT-IR and MS. The main evolved gases were determined as H 2 O, CO 2 and hydrocarbons such as CH 4 and temperature dependent profiles of the species were obtained. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fiber-optic Fourier transform infrared spectroscopy for remote label-free sensing of medical device surface contamination.

PubMed

Hassan, Moinuddin; Tan, Xin; Welle, Elissa; Ilev, Ilko

2013-05-01

As a potential major source of biochemical contamination, medical device surfaces are of critical safety concerns in the clinical practice and public health. The development of innovative sensing methods for accurate and real-time detection of medical device surface contamination is essential to protect patients from high risk infection. In this paper, we demonstrate an alternative fiber-optic Fourier Transform Infrared (FTIR) spectroscopy based sensing approach for remote, non-contact, and label-free detection of biochemical contaminants in the mid-infrared (mid-IR) region. The sensing probe is designed using mid-IR hollow fibers and FTIR measurements are carried out in reflection mode. Bovine Serum Albumin (BSA) and bacterial endotoxin of different concentrations under thoroughly dry condition are used to evaluate the detection sensitivity. The devised system can identify ≤0.0025% (≤4 × 10(11) molecules) BSA and 0.5% (0.5 EU/ml) endotoxin concentration. The developed sensing approach may be applied to detect various pathogens that pose public health threats.

Effects of Pulsed Electric Fields (PEF) on Vitamin C and Its Antioxidant Properties.

PubMed

Zhang, Zhi-Hong; Zeng, Xin-An; Brennan, Charles S; Brennan, Margaret; Han, Zhong; Xiong, Xia-Yu

2015-10-13

In this study, pulsed electric fields (PEF) treatments and their effects on the structure of vitamin C (VIT-C) were estimated by fluorescence and Fourier transform infrared (FT-IR) spectroscopy, the relative content of VIT-C was measured by HPLC and the antioxidant properties of treated VIT-C by DPPH radical scavenging as well as reducing power tests. The fluorescence intensity of treated VIT-C increased slightly compared to the untreated VIT-C. Moreover, the effect of PEF on the structure of VIT-C was observed using the FT-IR spectra. These phenomena indicated that the PEF affected the conformation of VIT-C, which promoted the VIT-C isomer transformed enol-form into keto-form. In addition, the PEF treatments did not suffer the damage to VIT-C and could slow down the oxidation process in involving of experimental conditions by HPLC. The antioxidant properties of the treated VIT-C were enhanced, which was proved by radical scavenging and also the reducing power tests.

Structural, thermal and electrical characterizations of multiwalled carbon nanotubes and polyaniline composite

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

Singh, Kamal, E-mail: singhkamal204@gmail.com; Garg, Leena; Singh, Jaspal

2016-05-06

The undoped and doped composite of MWNTs (Multiwalled Carbon Nanotubes) with PANI (/Polyaniline) was prepared by chemical oxidative polymerization. The MWNTs/PANI composites have been characterized by using various techniques like Thermogravometric Analysis (TGA), Fourier transform infrared (FT-IR) spectrometer and Field emission scanning electron microscope (FE-SEM) and conductivity measurement by using two probe method. TGA results has shown that thermal stability followed the pattern undoped MWNTs/PANI composite < doped MWNTs/PANI composite. FE-SEM micrographs demonstrated the morphological changes on the surface of MWNTs as a result of composite formation. Fourier transformed infrared (FT-IR) spectra ascertained the formation of the composite. Study ofmore » electrical characteristics demonstrated that the doped MWNTs/PANI composite (1.2 × 10{sup 1} Scm{sup −1}) have better conductivity than the undoped MWNTs/PANI composite (10{sup −4} Scm{sup −1}). These CNTs based polymeric composites are of great importance in developing new nano-scale devices for future chemical, mechanical and electronic applications.« less

Discrimination between Bacillus and Alicyclobacillus isolates in apple juice by Fourier transform infrared spectroscopy and multivariate analysis.

PubMed

Al-Holy, Murad A; Lin, Mengshi; Alhaj, Omar A; Abu-Goush, Mahmoud H

2015-02-01

Alicyclobacillus is a causative agent of spoilage in pasteurized and heat-treated apple juice products. Differentiating between this genus and the closely related Bacillus is crucially important. In this study, Fourier transform infrared spectroscopy (FT-IR) was used to identify and discriminate between 4 Alicyclobacillus strains and 4 Bacillus isolates inoculated individually into apple juice. Loading plots over the range of 1350 and 1700 cm(-1) reflected the most distinctive biochemical features of Bacillus and Alicyclobacillus. Multivariate statistical methods (for example, principal component analysis and soft independent modeling of class analogy) were used to analyze the spectral data. Distinctive separation of spectral samples was observed. This study demonstrates that FT-IR spectroscopy in combination with multivariate analysis could serve as a rapid and effective tool for fruit juice industry to differentiate between Bacillus and Alicyclobacillus and to distinguish between species belonging to these 2 genera. © 2015 Institute of Food Technologists®

Characterization of Archaeological Sediments Using Fourier Transform Infrared (FT-IR) and Portable X-ray Fluorescence (pXRF): An Application to Formative Period Pyro-Industrial Sites in Pacific Coastal Southern Chiapas, Mexico.

PubMed

Neff, Hector; Bigney, Scott J; Sakai, Sachiko; Burger, Paul R; Garfin, Timothy; George, Richard G; Culleton, Brendan J; Kennett, Douglas J

2016-01-01

Archaeological sediments from mounds within the mangrove zone of far-southern Pacific coastal Chiapas, Mexico, are characterized in order to test the hypothesis that specialized pyro-technological activities of the region's prehistoric inhabitants (salt and ceramic production) created the accumulations visible today. Fourier transform infrared spectroscopy (FT-IR) is used to characterize sediment mineralogy, while portable X-ray fluorescence (pXRF) is used to determine elemental concentrations. Elemental characterization of natural sediments by both instrumental neutron activation analysis (INAA) and pXRF also contribute to understanding of processes that created the archaeological deposits. Radiocarbon dates combined with typological analysis of ceramics indicate that pyro-industrial activity in the mangrove zone peaked during the Late Formative and Terminal Formative periods, when population and monumental activity on the coastal plain and piedmont were also at their peaks. © The Author(s) 2015.

Fiber-optic Fourier transform infrared spectroscopy for remote label-free sensing of medical device surface contamination

NASA Astrophysics Data System (ADS)

Hassan, Moinuddin; Tan, Xin; Welle, Elissa; Ilev, Ilko

2013-05-01

As a potential major source of biochemical contamination, medical device surfaces are of critical safety concerns in the clinical practice and public health. The development of innovative sensing methods for accurate and real-time detection of medical device surface contamination is essential to protect patients from high risk infection. In this paper, we demonstrate an alternative fiber-optic Fourier Transform Infrared (FTIR) spectroscopy based sensing approach for remote, non-contact, and label-free detection of biochemical contaminants in the mid-infrared (mid-IR) region. The sensing probe is designed using mid-IR hollow fibers and FTIR measurements are carried out in reflection mode. Bovine Serum Albumin (BSA) and bacterial endotoxin of different concentrations under thoroughly dry condition are used to evaluate the detection sensitivity. The devised system can identify ≤0.0025% (≤4 × 1011 molecules) BSA and 0.5% (0.5 EU/ml) endotoxin concentration. The developed sensing approach may be applied to detect various pathogens that pose public health threats.

Analysis of grain boundary phase devitrification of Y2O3- and Al2O3-doped Si3N4

NASA Technical Reports Server (NTRS)

Hench, L. L.; Vaidyanathan, P. N.

1983-01-01

The present study has the objective to show that a Fourier Transform IR (FTIR) spectrometer in a single-beam reflection mode can be used for direct comparison of fractured vs nonfractured Si3N4 surfaces. This can be done because the FTIR method permits a digital summation of nearly 1000 scans of the fracture surface. Commercial-grade Si3N4, Y2O3, and Al2O3 were used in the study. The samples were heat treated in a vacuum induction heating furnace at either 1000 C for 10 h or 1200 C for 10 h each. Use of Fourier transform IR reflection spectroscopic analysis and X-ray diffraction shows that 10 h at 1200 C is sufficient to devitrify the amorphous grain boundary phase of Si3N4 containing 15 percent Y2O3 + 2 percent Al2O3 densification aids.

Effects of Pulsed Electric Fields (PEF) on Vitamin C and Its Antioxidant Properties

PubMed Central

Zhang, Zhi-Hong; Zeng, Xin-An; Brennan, Charles S.; Brennan, Margaret; Han, Zhong; Xiong, Xia-Yu

2015-01-01

In this study, pulsed electric fields (PEF) treatments and their effects on the structure of vitamin C (VIT-C) were estimated by fluorescence and Fourier transform infrared (FT-IR) spectroscopy, the relative content of VIT-C was measured by HPLC and the antioxidant properties of treated VIT-C by DPPH radical scavenging as well as reducing power tests. The fluorescence intensity of treated VIT-C increased slightly compared to the untreated VIT-C. Moreover, the effect of PEF on the structure of VIT-C was observed using the FT-IR spectra. These phenomena indicated that the PEF affected the conformation of VIT-C, which promoted the VIT-C isomer transformed enol-form into keto-form. In addition, the PEF treatments did not suffer the damage to VIT-C and could slow down the oxidation process in involving of experimental conditions by HPLC. The antioxidant properties of the treated VIT-C were enhanced, which was proved by radical scavenging and also the reducing power tests. PMID:26473846

Rapid discrimination of cultivated Codonopsis lanceolata in different ages by FT-IR and 2DCOS-IR

NASA Astrophysics Data System (ADS)

Zhu, Yun; Xu, Chang-hua; Huang, Jian; Li, Guo-yu; Liu, Xin-Hu; Sun, Su-qin; Wang, Jin-hui

2014-07-01

Deodeok (Codonopsis lanceolata) root, a traditional Chinese herbal medicine, has been used to treat lung ailments, rheumatism, menstrual disturbance and bruises with a long history in China and some other Asian countries. In this study, four types of Deodeok with different growth years were discriminated and identified by a Tri-step infrared spectroscopy method (Fourier transform-infrared spectroscopy (conventional FT-IR) coupled with second derivative infrared spectroscopy (SD-IR) and two dimensional correlation infrared spectroscopy(2DCOS-IR) under thermal perturbation. Although only small differences were found in the FT-IR spectra of the samples, the positions and intensities of peaks around 1736, 1634, 1246, 1055, 1033, 818, 779 cm-1 could be considered as the key factors for discriminating them. The differences among them were amplified by their SD-IR spectra. The 2DCOS-IR spectra provided obvious dynamic chemical structure information of Deodeok samples, which present different particular auto peak clusters in the range of 875-1130 cm-1 and 1170-1630 cm-1, respectively. It was demonstrated that the content of triterpene were decreasing when C. lanceolata were growing older, but the relative content of saccharides initially increased and decreased significantly afterwards. It indicated a general trend that the content of polysaccharides accumulated with increasing years. Specifically, the content of polysaccharides accumulated in the root of 2-year-old plant was the lowest, 4-years-old was the highest, and then the content decreased gradually. Furthermore, according to the differences of locations and intensities of auto-peaks in 2D-IR spectra, the integral changes of components were revealed. This study offers a promising method inherent with cost-effective and time-saving to characterize and discriminate the complicated system like Deodeok.

Spectral Mining for Discriminating Blood Origins in the Presence of Substrate Interference via Attenuated Total Reflection Fourier Transform Infrared Spectroscopy: Postmortem or Antemortem Blood?

PubMed

Takamura, Ayari; Watanabe, Ken; Akutsu, Tomoko; Ikegaya, Hiroshi; Ozawa, Takeaki

2017-09-19

Often in criminal investigations, discrimination of types of body fluid evidence is crucially important to ascertain how a crime was committed. Compared to current methods using biochemical techniques, vibrational spectroscopic approaches can provide versatile applicability to identify various body fluid types without sample invasion. However, their applicability is limited to pure body fluid samples because important signals from body fluids incorporated in a substrate are affected strongly by interference from substrate signals. Herein, we describe a novel approach to recover body fluid signals that are embedded in strong substrate interferences using attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy and an innovative multivariate spectral processing. This technique supported detection of covert features of body fluid signals, and then identified origins of body fluid stains on substrates. We discriminated between ATR FT-IR spectra of postmortem blood (PB) and those of antemortem blood (AB) by creating a multivariate statistics model. From ATR FT-IR spectra of PB and AB stains on interfering substrates (polyester, cotton, and denim), blood-originated signals were extracted by a weighted linear regression approach we developed originally using principal components of both blood and substrate spectra. The blood-originated signals were finally classified by the discriminant model, demonstrating high discriminant accuracy. The present method can identify body fluid evidence independently of the substrate type, which is expected to promote the application of vibrational spectroscopic techniques in forensic body fluid analysis.

Discrimination and prediction of the origin of Chinese and Korean soybeans using Fourier transform infrared spectrometry (FT-IR) with multivariate statistical analysis

PubMed Central

Lee, Byeong-Ju; Zhou, Yaoyao; Lee, Jae Soung; Shin, Byeung Kon; Seo, Jeong-Ah; Lee, Doyup; Kim, Young-Suk

2018-01-01

The ability to determine the origin of soybeans is an important issue following the inclusion of this information in the labeling of agricultural food products becoming mandatory in South Korea in 2017. This study was carried out to construct a prediction model for discriminating Chinese and Korean soybeans using Fourier-transform infrared (FT-IR) spectroscopy and multivariate statistical analysis. The optimal prediction models for discriminating soybean samples were obtained by selecting appropriate scaling methods, normalization methods, variable influence on projection (VIP) cutoff values, and wave-number regions. The factors for constructing the optimal partial-least-squares regression (PLSR) prediction model were using second derivatives, vector normalization, unit variance scaling, and the 4000–400 cm–1 region (excluding water vapor and carbon dioxide). The PLSR model for discriminating Chinese and Korean soybean samples had the best predictability when a VIP cutoff value was not applied. When Chinese soybean samples were identified, a PLSR model that has the lowest root-mean-square error of the prediction value was obtained using a VIP cutoff value of 1.5. The optimal PLSR prediction model for discriminating Korean soybean samples was also obtained using a VIP cutoff value of 1.5. This is the first study that has combined FT-IR spectroscopy with normalization methods, VIP cutoff values, and selected wave-number regions for discriminating Chinese and Korean soybeans. PMID:29689113

On the Use of Fourier Transform Infrared (FT-IR) Spectroscopy and Synthetic Calibration Spectra to Quantify Gas Concentrations in a Fischer-Tropsch Catalyst System

NASA Technical Reports Server (NTRS)

Ferguson, Frank T.; Johnson, Natasha M.; Nuth, Joseph A., III

2015-01-01

One possible origin of prebiotic organic material is that these compounds were formed via Fischer-Tropsch-type (FTT) reactions of carbon monoxide and hydrogen on silicate and oxide grains in the warm, inner-solar nebula. To investigate this possibility, an experimental system has been built in which the catalytic efficiency of different grain-analog materials can be tested. During such runs, the gas phase above these grain analogs is sampled using Fourier transform infrared (FT-IR) spectroscopy. To provide quantitative estimates of the concentration of these gases, a technique in which high-resolution spectra of the gases are calculated using the high-resolution transmission molecular absorption (HITRAN) database is used. Next, these spectra are processed via a method that mimics the processes giving rise to the instrumental line shape of the FT-IR spectrometer, including apodization, self-apodization, and broadening due to the finite resolution. The result is a very close match between the measured and computed spectra. This technique was tested using four major gases found in the FTT reactions: carbon monoxide, methane, carbon dioxide, and water. For the ranges typical of the FTT reactions, the carbon monoxide results were found to be accurate to within 5% and the remaining gases accurate to within 10%. These spectra can then be used to generate synthetic calibration data, allowing the rapid computation of the gas concentrations in the FTT experiments.

On the Use of Fourier Transform Infrared (FT-IR) Spectroscopy and Synthetic Calibration Spectra to Quantify Gas Concentrations in a Fischer-Tropsch Catalyst System.

PubMed

Ferguson, Frank T; Johnson, Natasha M; Nuth, Joseph A

2015-10-01

One possible origin of prebiotic organic material is that these compounds were formed via Fischer-Tropsch-type (FTT) reactions of carbon monoxide and hydrogen on silicate and oxide grains in the warm, inner-solar nebula. To investigate this possibility, an experimental system has been built in which the catalytic efficiency of different grain-analog materials can be tested. During such runs, the gas phase above these grain analogs is sampled using Fourier transform infrared (FT-IR) spectroscopy. To provide quantitative estimates of the concentration of these gases, a technique in which high-resolution spectra of the gases are calculated using the High-Resolution Transmission Molecular Absorption (HITRAN) database is used. Next, these spectra are processed via a method that mimics the processes giving rise to the instrumental line shape of the FT-IR spectrometer, including apodization, self-apodization, and broadening due to the finite resolution. The result is a very close match between the measured and computed spectra. This technique was tested using four major gases found in the FTT reactions: carbon monoxide, methane, carbon dioxide, and water. For the ranges typical of the FTT reactions, the carbon monoxide results were found to be accurate to within 5% and the remaining gases accurate to within 10%. These spectra can then be used to generate synthetic calibration data, allowing the rapid computation of the gas concentrations in the FTT experiments.

Structure, spectra and thermal, mechanical, Faraday rotation properties of novel diamagnetic SeO2-PbO-Bi2O3-B2O3 glasses

NASA Astrophysics Data System (ADS)

Chen, Qiuling; Su, Kai; Li, Yantao; Zhao, Zhiwei

2018-06-01

Faraday rotation diamagnetic glass has attracted research attentions in photonics, sensing and magneto optical devices due to their high refractive index, wide transmittance in UV and Fourier transform infrared (FT-IR) range and temperature independent Faraday rotation. Selenite modified heavy metal oxides glasses with composition of xSeO2-(10-x) B2O3-45PbO-45Bi2O3 (x = 0, 1, 5 and 10mol%) and 15%SeO2-40%PbO-45%Bi2O3 have been fabricated by melt-quenching method in present study. The influence of SeO2 on glass forming ability, thermal, mechanical properties and Faraday rotation were evaluated through X-ray Diffraction (XRD), Fourier transforms infrared spectra (FT-IR), Raman, X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), Vicker's hardness and Verdet constant measurements. XRD spectra reveal that the good vitrification was achieved for glass with SeO2 amounts ≤10% even without B2O3. FT-IR, Raman and XPS spectra ascertain the existence of characteristic vibration of SeO4, SeO3, PbO4, BiO3 and BO3 units. The incorporation of SeO2 increases the connectivity of glassy network by increasing the Tg, thermal stability and mechanical hardness. The small band gap, high polarizable Se4+ ions and isolated SeO3 units contribute to Faraday rotation improvement.

Atmospheric-Pressure Plasma Interaction with Soft Materials as Fundamental Processes in Plasma Medicine.

PubMed

Takenaka, Kosuke; Miyazaki, Atsushi; Uchida, Giichiro; Setsuhara, Yuichi

2015-03-01

Molecular-structure variation of organic materials irradiated with atmospheric pressure He plasma jet have been investigated. Optical emission spectrum in the atmospheric-pressure He plasma jet has been measured. The spectrum shows considerable emissions of He lines, and the emission of O and N radicals attributed to air. Variation in molecular structure of Polyethylene terephthalate (PET) film surface irradiated with the atmospheric-pressure He plasma jet has been observed via X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). These results via XPS and FT-IR indicate that the PET surface irradiated with the atmospheric-pressure He plasma jet was oxidized by chemical and/or physical effect due to irradiation of active species.

Multiple functionalization of multi-walled carbon nanotubes with carboxyl and amino groups

NASA Astrophysics Data System (ADS)

Zhao, Zhiyuan; Yang, Zhanhong; Hu, Youwang; Li, Jianping; Fan, Xinming

2013-07-01

In this paper, carboxyl and amino groups have been introduced onto the surface of the multi-walled carbon nanotubes (MWCNTs) by the mixed acid treatment and the diazonium reaction, respectively. The presence of multifunctionality groups on the MWCNTs has been characterized by Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric (TGA) analysis, Raman spectra, scanning electron microscopy (SEM) and energy dispersive X-ray spectrum (EDS). The multifunctionalized carbon nanotubes were further utilized to react with acetyl chloride and ethylenediamine (EDA). The formation of the amide bond in the grafting reaction has been confirmed by FT-IR spectroscopy. The result indicates that the further grafting is successful. The multifunctionalized MWCNTs can be a new versatile platform for many interesting applications.

DIRECT-DEPOSITION INFRARED SPECTROMETRY WITH GAS AND SUPERCRITICAL FLUID CHROMATOGRAPHY

EPA Science Inventory

A direct-deposition Fourier transform infrared (FT-IR) system has been evaluated for applicability to gas chromatography (GC) and supercritical fluid chromatography (SFC) of environmental analytes. A 100-um i.d. fused-silica transfer line was used for GC, and a 50-um transfer lin...

Predicting ambient aerosol Thermal Optical Reflectance (TOR) measurements from infrared spectra: elemental carbon

NASA Astrophysics Data System (ADS)

Dillner, A. M.; Takahama, S.

2015-06-01

Elemental carbon (EC) is an important constituent of atmospheric particulate matter because it absorbs solar radiation influencing climate and visibility and it adversely affects human health. The EC measured by thermal methods such as Thermal-Optical Reflectance (TOR) is operationally defined as the carbon that volatilizes from quartz filter samples at elevated temperatures in the presence of oxygen. Here, methods are presented to accurately predict TOR EC using Fourier Transform Infrared (FT-IR) absorbance spectra from atmospheric particulate matter collected on polytetrafluoroethylene (PTFE or Teflon) filters. This method is similar to the procedure tested and developed for OC in prior work (Dillner and Takahama, 2015). Transmittance FT-IR analysis is rapid, inexpensive, and non-destructive to the PTFE filter samples which are routinely collected for mass and elemental analysis in monitoring networks. FT-IR absorbance spectra are obtained from 794 filter samples from seven Interagency Monitoring of PROtected Visual Environment (IMPROVE) sites collected during 2011. Partial least squares regression is used to calibrate sample FT-IR absorbance spectra to collocated TOR EC measurements. The FTIR spectra are divided into calibration and test sets. Two calibrations are developed, one which is developed from uniform distribution of samples across the EC mass range (Uniform EC) and one developed from a~uniform distribution of low EC mass samples (EC < 2.4 μg, Low Uniform EC). A hybrid approach which applies the low EC calibration to low EC samples and the Uniform EC calibration to all other samples is used to produces predictions for low EC samples that have mean error on par with parallel TOR EC samples in the same mass range and an estimate of the minimum detection limit (MDL) that is on par with TOR EC MDL. For all samples, this hybrid approach leads to precise and accurate TOR EC predictions by FT-IR as indicated by high coefficient of variation (R2; 0.96), no bias (0.00 μg m-3, concentration value based on the nominal IMPROVE sample volume of 32.8 m-3), low error (0.03 μg m-3) and reasonable normalized error (21 %). These performance metrics can be achieved with various degrees of spectral pretreatment (e.g., including or excluding substrate contributions to the absorbances) and are comparable in precision and accuracy to collocated TOR measurements. Only the normalized error is higher for the FT-IR EC measurements than for collocated TOR. FT-IR spectra are also divided into calibration and test sets by the ratios OC/EC and ammonium/EC to determine the impact of OC and ammonium on EC prediction. We conclude that FT-IR analysis with partial least squares regression is a robust method for accurately predicting TOR EC in IMPROVE network samples; providing complementary information to TOR OC predictions (Dillner and Takahama, 2015) and the organic functional group composition and organic matter (OM) estimated previously from the same set of sample spectra (Ruthenburg et al., 2014).

Solid-state NMR and IR for the analysis of pharmaceutical solids: polymorphs of fosinopril sodium.

PubMed

Brittain, H G; Morris, K R; Bugay, D E; Thakur, A B; Serajuddin, A T

1993-01-01

The two polymorphic modifications of fosinopril sodium have been characterized as to their differences in melting behaviour, powder X-ray diffraction patterns, Fourier transform infrared spectra (FTIR), and solid-state 31P- and 13C-NMR spectra. The polymorphs were found to be enantiotropically related based upon melting point, heat of fusion, and solution mediated transformation data. Analysis of the solid-state FTIR and 13C-NMR data indicated that the environment of the acetal side chain of fosinopril sodium differed in two polymorphs, and that there might be cis-trans isomerization about the C6-N peptide bond. These conformational differences are postulated as the origin of the observed polymorphism.

Investigation of Apple Jelly Contaminant in Military Jet Fuel

DTIC Science & Technology

2002-03-01

Page 10.2.4FT-IR Properties of Sodium Polyacrylate ..................................................... 134 10.2.5Effect of SDA on Thick Apple Jelly...Acidified Synthetic Apple Jelly JAW1-56-1 ......... 133 64. FT-IR Spectrum of Sodium Polyacrylate ...135 65. FT-IR Spectrum of Sodium Polyacrylate (1450 to 1760 cm-1) ............................... 135 66. FT-IR Spectra of SDA, Thick

CHLORINATED SOLVENT MOVEMENT THROUGH PLANTS MONITORED BY FOURIER TRANSFORM INFRARED (FT-IR) SPECTROMETRY. (R825549C062)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

Sensing the Structural Differences in Cellulose from Apple and Bacterial Cell Wall Materials by Raman and FT-IR Spectroscopy

PubMed Central

Szymańska-Chargot, Monika; Cybulska, Justyna; Zdunek, Artur

2011-01-01

Raman and Fourier Transform Infrared (FT-IR) spectroscopy was used for assessment of structural differences of celluloses of various origins. Investigated celluloses were: bacterial celluloses cultured in presence of pectin and/or xyloglucan, as well as commercial celluloses and cellulose extracted from apple parenchyma. FT-IR spectra were used to estimate of the Iβ content, whereas Raman spectra were used to evaluate the degree of crystallinity of the cellulose. The crystallinity index (XCRAMAN%) varied from −25% for apple cellulose to 53% for microcrystalline commercial cellulose. Considering bacterial cellulose, addition of xyloglucan has an impact on the percentage content of cellulose Iβ. However, addition of only xyloglucan or only pectins to pure bacterial cellulose both resulted in a slight decrease of crystallinity. However, culturing bacterial cellulose in the presence of mixtures of xyloglucan and pectins results in an increase of crystallinity. The results confirmed that the higher degree of crystallinity, the broader the peak around 913 cm−1. Among all bacterial celluloses the bacterial cellulose cultured in presence of xyloglucan and pectin (BCPX) has the most similar structure to those observed in natural primary cell walls. PMID:22163913

Piper betle-mediated green synthesis of biocompatible gold nanoparticles

NASA Astrophysics Data System (ADS)

Punuri, Jayasekhar Babu; Sharma, Pragya; Sibyala, Saranya; Tamuli, Ranjan; Bora, Utpal

2012-08-01

Here, we report the novel use of the ethonolic leaf extract of Piper betle for gold nanoparticle (AuNP) synthesis. The successful formation of AuNPs was confirmed by UV-visible spectroscopy, and different parameters such as leaf extract concentration (2%), gold salt concentration (0.5 mM), and time (18 s) were optimized. The synthesized AuNPs were characterized with different biophysical techniques such as transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDX). TEM experiments showed that nanoparticles were of various shapes and sizes ranging from 10 to 35 nm. FT-IR spectroscopy revealed that AuNPs were functionalized with biomolecules that have primary amine group -NH2, carbonyl group, -OH groups, and other stabilizing functional groups. EDX showed the presence of the elements on the surface of the AuNPs. FT-IR and EDX together confirmed the presence of biomolecules bounded on the AuNPs. Cytotoxicity of the AuNPs was tested on HeLa and MCF-7 cancer cell lines, and they were found to be nontoxic, indicating their biocompatibility. Thus, synthesized AuNPs have potential for use in various biomedical applications.

Nondestructive identification for red ink entries of seals by Raman and Fourier transform infrared spectrometry.

PubMed

Wang, Xiang-Feng; Yu, Jing; Zhang, Ai-Lan; Zhou, Dai-Wei; Xie, Meng-Xia

2012-11-01

Determination of the red ink entries of seals on documents can provide valuable evidences for solving related crimes, distinguishing the truth of artworks, and so establishment of nondestructive approaches would play a key role in forensic analysis and related aspects. Raman and FT-IR spectroscopy have been applied for analyzing 105 kinds of red ink entries on documents. The dye components of the ink entries were identified by FT-Raman and confocal Raman microspectroscopy, and then the ink entries were classified into four groups based on these dye components. The ink entries were further discriminated by their FT-IR spectra according to adsorption peaks of the main components, the relative intensities of the characteristic bands and the profiles of the spectra. The results showed that 70 ink entries out of 105 have been individually identified and the remaining 35 ink entries can be divided into 13 subclasses. Combination of Raman and FT-IR spectroscopic methods can provide a powerful nondestructive discriminating tool for identification of the red ink entries of seals on papers. These approaches would have potential application in archeology, art and forensic science. Copyright © 2012 Elsevier B.V. All rights reserved.

Evaluation of a setting reaction pathway in the novel composite TiHA-CSD bone cement by FT-Raman and FT-IR spectroscopy

NASA Astrophysics Data System (ADS)

Paluszkiewicz, Czesława; Czechowska, Joanna; Ślósarczyk, Anna; Paszkiewicz, Zofia

2013-02-01

The aim of this study was to determine a setting reaction pathway in a novel, surgically handy implant material, based on calcium sulfate hemihydrate (CSH) and titanium doped hydroxyapatite (TiHA). The previous studies confirmed superior biological properties of TiHA in comparison to the undoped hydroxyapatite (HA) what makes it highly attractive for future medical applications. In this study the three types of titanium modified HA powders: untreated, calcined at 800 °C, sintered at 1250 °C and CSH were used to produce bone cements. The Fourier Transform-InfraRed (FT-IR) spectroscopy and Raman spectroscopy were applied to evaluate processes taking place during the setting of the studied materials. Our results undoubtedly confirmed that the reaction pathways and the phase compositions differed significantly for set cements and were dependent on the initial heat treatment of TiHA powder. Final materials were multiphase composites consisting of calcium sulfate dihydrate, bassanite, tricalcium phosphate, hydroxyapatite and calcium titanate (perovskite). The FT-IR and Scanning Electron Microscopy (SEM) measurements performed after the incubation of the cement samples in the simulated body fluid (SBF), indicate on high bioactive potential of the obtained bone cements.

Catalytic and antibacterial properties of silver nanoparticles green biosynthesized using soluble green tea powder

NASA Astrophysics Data System (ADS)

Xu, Wei; Fan, Yapei; Liu, Xinfang; Luo, Denglin; Liu, Huan; Yang, Ningning

2018-04-01

Silver nanoparticles (Ag NPs) were green fabricated using soluble green tea powder (SGTP) as stabilizer and reducing agent. The properties and morphology of Ag NPs were investigated through UV–visible spectroscopy, field emission transmission electron microscope (FE-TEM) and fourier transform infrared (FT-IR). The spectroscopy showed surface plasmon resonance around at 420 nm revealing the synthesis of Ag NPs. FE-TEM results confirmed that the Ag NPs are spherical and face-centered cubic structure. FT-IR spectroscopy identified the role of various functional groups in the nanoparticle synthesis. The one spot biosynthesized Ag NPs showed favourable antibacterial properties on Escherichia coli and Staphyloccocus aureus, and excellent catalytic reduction of 4-nitrophenol. This work provided a feasible, green method to fabricate Ag NPs with promising photocatalytic and antimicrobial activities.

Polyethyleneglycol/silver functionalized reduced graphene oxide aerogel for environmental application

NASA Astrophysics Data System (ADS)

Kumari, G. Vanitha; Asha, S.; Ananth, A. Nimrodh; Rajan, M. A. Jothi; Mathavan, T.

2018-04-01

Polyethylene glycol (PEG)/Silver (Ag) functionalized reduced graphene oxide aerogel (RGOA) was synthesized. PEG/Ag decorated reduced graphene oxide aerogel was characterized using XRD, Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR). The surface morphology of PEG/Ag/RGOA was analyzed using scanning electron microscope. The non-covalent interaction between reduced graphene oxide layers and the interaction between PEG and Ag on RGOA were studied by FT-IR spectra. It was observed that the interaction between Ag and PEG could enhance the properties of RGOA. Methyl Orange (MO) dye degradation was observed from UV-Vis Spectra. The process was studied by monitoring the simultaneous decrease in the height of UV-Vis absorption peak of dye solution. The results show that PEG/RGOA and PEG/Ag/RGOA are an efficient catalyst for dye degradation.

Spectroscopic investigation of interaction between mangiferin and bovine serum albumin

NASA Astrophysics Data System (ADS)

Lin, Hui; Lan, Jingfeng; Guan, Min; Sheng, Fenling; Zhang, Haixia

2009-09-01

The mechanism of interaction between mangiferin (MA) and bovine serum albumin (BSA) in aqueous solution was investigated by fluorescence spectra, synchronous fluorescence spectra, absorbance spectra and Fourier transform infrared (FT-IR) spectroscopy. The binding constants and binding sites of MA to BSA at different reaction times were calculated. And the distance between MA and BSA was estimated to be 5.20 nm based on Föster's theory. In addition, synchronous fluorescence and FT-IR measurements revealed that the secondary structures of the protein changed after the interaction of MA with BSA. As a conclusion, the interaction between the anti-diabetes Chinese medicine MA and BSA may provide some significant information for the mechanism of the traditional chinese medicine MA on the protein level to cure diabetes or other diseases.

Micro-Raman and FT-IR spectroscopic studies of ceramic shards excavated from ancient Stratonikeia city at Eskihisar village in West-South Turkey

NASA Astrophysics Data System (ADS)

Bahçeli, Semiha; Güleç, Gamze; Erdoğan, Hasan; Söğüt, Bilal

2016-02-01

In this study, micro-Raman and Fourier transformed infrared (FT-IR) spectroscopies, X-ray diffraction (XRD) and scanning electron microscope with energy dispersive X-ray (SEM-EDX) were used to characterize the mineralogical structures of pigments of four ceramic fragments in which one of them belongs to Hellenistic period (1st - IVth century BC) and other three ceramic shards belong to Early Rome (IVth century BC- 1st century AD) excavated from Stratonikeia ancient city. In the results of investigations on these four ceramic fragments, the various phases were identified: quartz, kaolinite, albit (or Na-feldspar), calcite, anastase, hematite and magnetite. Furthermore, the obtained findings indicate that firing temperature is about 800-850 °C for all the shards.

The Isolation of Nanofibre Cellulose from Oil Palm Empty Fruit Bunch Via Steam Explosion and Hydrolysis with HCl 10%

NASA Astrophysics Data System (ADS)

Gea, S.; Zulfahmi, Z.; Yunus, D.; Andriayani, A.; Hutapea, Y. A.

2018-03-01

Cellulose nanofibrils were obtained from oil palm empty fruit bunch using steam explosion and hydrolized with 10% solution of HCl. Steam explosion coupled with acid hydrolysis pretreatment on the oil palm empty fruit bunch was very effective in the depolymerization and defibrillation process of the fibre to produce fibers in nanodimension. Structural analysis of steam exploded fibers was determined by Fourier Transform Infrared (FT-IR) spectroscopy. Thermal stability of cellulose measured using image analysis software image J. Characterization of the fibers by TEM and SEM displayed that fiber diameter decreases with mechanical-chemical treatment and final nanofibril size was 20-30 nm. FT-IR and TGA data confirmed the removal of hemicellulose and lignin during the chemical treatment process.

An FTIR point sensor for identifying chemical WMD and hazardous materials

NASA Astrophysics Data System (ADS)

Norman, Mark L.; Gagnon, Aaron M.; Reffner, John A.; Schiering, David W.; Allen, Jeffrey D.

2004-03-01

A new point sensor for identifying chemical weapons of mass destruction and other hazardous materials based on Fourier transform infrared (FT-IR) spectroscopy is presented. The sensor is a portable, fully functional FT-IR system that features a miniaturized Michelson interferometer, an integrated diamond attenuated total reflection (ATR) sample interface, and an embedded on-board computer. Samples are identified by an automated search algorithm that compares their infrared spectra to digitized databases that include reference spectra of nerve and blister agents, toxic industrial chemicals, and other hazardous materials. The hardware and software are designed for use by technicians with no background in infrared spectroscopy. The unit, which is fully self-contained, can be hand-carried and used in a hot zone by personnel in Level A protective gear, and subsequently decontaminated by spraying or immersion. Wireless control by a remote computer is also possible. Details of the system design and performance, including results of field validation tests, are discussed.

Pressure jump relaxation setup with IR detection and millisecond time resolution

NASA Astrophysics Data System (ADS)

Schiewek, Martin; Krumova, Marina; Hempel, Günter; Blume, Alfred

2007-04-01

An instrument is described that allows the use of Fourier transform infrared (FTIR) spectroscopy as a detection system for kinetic processes after a pressure jump of up to 100bars. The pressure is generated using a high performance liquid chromatography (HPLC) pump and water as a pressure transducing medium. A flexible membrane separates the liquid sample in the IR cell from the pressure transducing medium. Two electromagnetic switching valves in the setup enable pressure jumps with a decay time of 4ms. The FTIR spectrometer is configured to measure time resolved spectra in the millisecond time regime using the rapid scan mode. All components are computer controlled. For a demonstration of the capability of the method first results on the kinetics of a phase transition between two lamellar phases of an aqueous phospholipid dispersion are presented. This combination of FTIR spectroscopy with the pressure jump relaxation technique can also be used for other systems which display cooperative transitions with concomitant volume changes.

Separation and determination of estrogen in the water environment by high performance liquid chromatography-fourier transform infrared spectroscopy

PubMed Central

Zheng, Bei; Li, Wentao; Li, Hongyan; Liu, Lin; Lei, Pei; Ge, Xiaopeng; Yu, Zhiyong; Zhou, Yiqi

2016-01-01

The components for connecting high-performance liquid chromatography (HPLC) with Fourier-transform infrared spectroscopy (FTIR) were investigated to determine estrogen in the water environment, including heating for atomization, solvent removal, sample deposition, drive control, spectrum collection, chip swap, cleaning and drying. Results showed that when the atomization temperature was increased to 388 K, the interference of mobile phase components (methanol, H2O, acetonitrile, and NaH2PO4) were completely removed in the IR measurement of estrogen, with 0.999 of similarity between IR spectra obtained after separation and corresponding to the standard IR spectra. In experiments with varying HPLC injection volumes, high similarity for IR spectra was obtained at 20 ul injection volume at 0.01 mg/L BPA while a useful IR spectrum for 10 ng/L BPA was obtained at 80 ul injection volume. In addition, estrogen concentrations in the natural water samples were calculated semi-quantitatively from the peak intensities of IR spectrum in the mid-infrared region. PMID:27577974

Separation and determination of estrogen in the water environment by high performance liquid chromatography-fourier transform infrared spectroscopy

NASA Astrophysics Data System (ADS)

Zheng, Bei; Li, Wentao; Li, Hongyan; Liu, Lin; Lei, Pei; Ge, Xiaopeng; Yu, Zhiyong; Zhou, Yiqi

2016-08-01

The components for connecting high-performance liquid chromatography (HPLC) with Fourier-transform infrared spectroscopy (FTIR) were investigated to determine estrogen in the water environment, including heating for atomization, solvent removal, sample deposition, drive control, spectrum collection, chip swap, cleaning and drying. Results showed that when the atomization temperature was increased to 388 K, the interference of mobile phase components (methanol, H2O, acetonitrile, and NaH2PO4) were completely removed in the IR measurement of estrogen, with 0.999 of similarity between IR spectra obtained after separation and corresponding to the standard IR spectra. In experiments with varying HPLC injection volumes, high similarity for IR spectra was obtained at 20 ul injection volume at 0.01 mg/L BPA while a useful IR spectrum for 10 ng/L BPA was obtained at 80 ul injection volume. In addition, estrogen concentrations in the natural water samples were calculated semi-quantitatively from the peak intensities of IR spectrum in the mid-infrared region.

Application of second derivative spectroscopy for increasing molecular specificity of Fourier transform infrared spectroscopic imaging of articular cartilage.

PubMed

Rieppo, L; Saarakkala, S; Närhi, T; Helminen, H J; Jurvelin, J S; Rieppo, J

2012-05-01

Fourier transform infrared (FT-IR) spectroscopic imaging is a promising method that enables the analysis of spatial distribution of biochemical components within histological sections. However, analysis of FT-IR spectroscopic data is complicated since absorption peaks often overlap with each other. Second derivative spectroscopy is a technique which enhances the separation of overlapping peaks. The objective of this study was to evaluate the specificity of the second derivative peaks for the main tissue components of articular cartilage (AC), i.e., collagen and proteoglycans (PGs). Histological bovine AC sections were measured before and after enzymatic removal of PGs. Both formalin-fixed sections (n = 10) and cryosections (n = 6) were investigated. Relative changes in the second derivative peak heights caused by the removal of PGs were calculated for both sample groups. The results showed that numerous peaks, e.g., peaks located at 1202 cm(-1) and 1336 cm(-1), altered less than 5% in the experiment. These peaks were assumed to be specific for collagen. In contrast, two peaks located at 1064 cm(-1) and 1376 cm(-1) were seen to alter notably, approximately 50% or more. These peaks were regarded to be specific for PGs. The changes were greater in cryosections than formalin-fixed sections. The results of this study suggest that the second derivative spectroscopy offers a practical and more specific method than routinely used absorption spectrum analysis methods to obtain compositional information on AC with FT-IR spectroscopic imaging. Copyright © 2012 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Identification of authentic and adulterated Aquilariae Lignum Resinatum by Fourier transform infrared (FT-IR) spectroscopy and two-dimensional correlation analysis

NASA Astrophysics Data System (ADS)

Qu, Lei; Chen, Jian-bo; Zhou, Qun; Zhang, Gui-jun; Sun, Su-qin; Guo, Yi-zhen

2016-11-01

As a kind of expensive perfume and valuable herb, the commercial Aquilariae Lignum Resinatum (ALR) is often adulterated for economic motivations. In this research, Fourier transform infrared (FT-IR) spectroscopy and two-dimensional (2D) correlation analysis are employed to establish a simple and quick identification method for the authentic and adulterated ALR. In the conventional infrared spectra, the standard ALR has a strong peak at 1658 cm-1 referring to the conjugated carbonyl of resin, while this peak is absent in the adulterated samples. The position, intensity, and shape of the auto-peaks and cross-peaks of the authentic and adulterated ALR are much different in the synchronous 2D correlation spectra with thermal perturbation. In the range of 1700-1500 cm-1, the standard ALR has four obvious auto-peaks, while the strongest one is at 1659 cm-1. The adulterated sample w-1 has three obvious auto-peaks and the strongest one is at 1647 cm-1. The adulterated sample w-2 has three obvious auto-peaks and the strongest one is at 1519 cm-1. The adulterated sample w-3 has four obvious auto-peaks and the strongest one is at 1690 cm-1. The above auto-peaks confirm that the standard ALR contains a certain content of resin compounds, while the three counterfeits contain little or different resins. The results show the potential of FT-IR spectroscopy and 2D correlation analysis in the simple and quick identification of authentic and adulterated ALR.

Fourier Transform Infrared (FT-IR) and Laser Ablation Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) Imaging of Cerebral Ischemia: Combined Analysis of Rat Brain Thin Cuts Toward Improved Tissue Classification.

PubMed

Balbekova, Anna; Lohninger, Hans; van Tilborg, Geralda A F; Dijkhuizen, Rick M; Bonta, Maximilian; Limbeck, Andreas; Lendl, Bernhard; Al-Saad, Khalid A; Ali, Mohamed; Celikic, Minja; Ofner, Johannes

2018-02-01

Microspectroscopic techniques are widely used to complement histological studies. Due to recent developments in the field of chemical imaging, combined chemical analysis has become attractive. This technique facilitates a deepened analysis compared to single techniques or side-by-side analysis. In this study, rat brains harvested one week after induction of photothrombotic stroke were investigated. Adjacent thin cuts from rats' brains were imaged using Fourier transform infrared (FT-IR) microspectroscopy and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The LA-ICP-MS data were normalized using an internal standard (a thin gold layer). The acquired hyperspectral data cubes were fused and subjected to multivariate analysis. Brain regions affected by stroke as well as unaffected gray and white matter were identified and classified using a model based on either partial least squares discriminant analysis (PLS-DA) or random decision forest (RDF) algorithms. The RDF algorithm demonstrated the best results for classification. Improved classification was observed in the case of fused data in comparison to individual data sets (either FT-IR or LA-ICP-MS). Variable importance analysis demonstrated that both molecular and elemental content contribute to the improved RDF classification. Univariate spectral analysis identified biochemical properties of the assigned tissue types. Classification of multisensor hyperspectral data sets using an RDF algorithm allows access to a novel and in-depth understanding of biochemical processes and solid chemical allocation of different brain regions.

Early Alterations in Bone Characteristics of Type I Diabetic Rat Femur: A Fourier Transform Infrared (FT-IR) Imaging Study.

PubMed

Bozkurt, Ozlem; Bilgin, Mehmet Dincer; Evis, Zafer; Pleshko, Nancy; Severcan, Feride

2016-12-01

Alterations in microstructure and mineral features can affect the mechanical and chemical properties of bones and their capacity to resist mechanical forces. Controversial results on diabetic bone mineral content have been reported and little is known about the structural alterations in collagen, maturation of apatite crystals, and carbonate content in diabetic bone. This current study is the first to report the mineral and organic properties of cortical, trabecular, and growth plate regions of diabetic rat femurs using Fourier transform infrared (FT-IR) microspectroscopy and the Vickers microhardness test. Femurs of type I diabetic rats were embedded into polymethylmethacrylate blocks, which were used for FT-IR imaging and microhardness studies. A lower mineral content and microhardness, a higher carbonate content especially labile type carbonate content, and an increase in size and maturation of hydroxyapatite crystals were observed in diabetic femurs, which indicate that diabetes has detrimental effects on bone just like osteoporosis. There was a decrease in the level of collagen maturity in diabetic femurs, implying a decrease in bone collagen quality that may contribute to the decrease in tensile strength and bone fragility. Taken together, the findings revealed alterations in structure and composition of mineral and matrix components, and an altered quality and mechanical strength of rat femurs in an early stage of type I diabetes. The results contribute to the knowledge of structure-function relationship of mineral and matrix components in diabetic bone disorder and can further be used for diagnostic or therapeutic purposes. © The Author(s) 2016.

Fluorescence, aggregation properties and FT-IR microspectroscopy of elastin and collagen fibers.

PubMed

Vidal, Benedicto de Campos

2014-10-01

Histological and histochemical observations support the hypothesis that collagen fibers can link to elastic fibers. However, the resulting organization of elastin and collagen type complexes and differences between these materials in terms of macromolecular orientation and frequencies of their chemical vibrational groups have not yet been solved. This study aimed to investigate the macromolecular organization of pure elastin, collagen type I and elastin-collagen complexes using polarized light DIC-microscopy. Additionally, differences and similarities between pure elastin and collagen bundles (CB) were investigated by Fourier transform-infrared (FT-IR) microspectroscopy. Although elastin exhibited a faint birefringence, the elastin-collagen complex aggregates formed in solution exhibited a deep birefringence and formation of an ordered-supramolecular complex typical of collagen chiral structure. The FT-IR study revealed elastin and CB peptide NH groups involved in different types of H-bonding. More energy is absorbed in the vibrational transitions corresponding to CH, CH2 and CH3 groups (probably associated with the hydrophobicity demonstrated by 8-anilino-1-naphtalene sulfonic acid sodium salt [ANS] fluorescence), and to νCN, δNH and ωCH2 groups of elastin compared to CB. It is assumed that the α-helix contribution to the pure elastin amide I profile is 46.8%, whereas that of the B-sheet is 20% and that unordered structures contribute to the remaining percentage. An FT-IR profile library reveals that the elastin signature within the 1360-1189cm(-1) spectral range resembles that of Conex-Toray aramid fibers. Copyright © 2014 Elsevier GmbH. All rights reserved.

Combining Raman and FT-IR spectroscopy with quantitative isotopic labeling for differentiation of E. coli cells at community and single cell levels.

PubMed

Muhamadali, Howbeer; Chisanga, Malama; Subaihi, Abdu; Goodacre, Royston

2015-04-21

There is no doubt that the contribution of microbially mediated bioprocesses toward maintenance of life on earth is vital. However, understanding these microbes in situ is currently a bottleneck, as most methods require culturing these microorganisms to suitable biomass levels so that their phenotype can be measured. The development of new culture-independent strategies such as stable isotope probing (SIP) coupled with molecular biology has been a breakthrough toward linking gene to function, while circumventing in vitro culturing. In this study, for the first time we have combined Raman spectroscopy and Fourier transform infrared (FT-IR) spectroscopy, as metabolic fingerprinting approaches, with SIP to demonstrate the quantitative labeling and differentiation of Escherichia coli cells. E. coli cells were grown in minimal medium with fixed final concentrations of carbon and nitrogen supply, but with different ratios and combinations of (13)C/(12)C glucose and (15)N/(14)N ammonium chloride, as the sole carbon and nitrogen sources, respectively. The cells were collected at stationary phase and examined by Raman and FT-IR spectroscopies. The multivariate analysis investigation of FT-IR and Raman data illustrated unique clustering patterns resulting from specific spectral shifts upon the incorporation of different isotopes, which were directly correlated with the ratio of the isotopically labeled content of the medium. Multivariate analysis results of single-cell Raman spectra followed the same trend, exhibiting a separation between E. coli cells labeled with different isotopes and multiple isotope levels of C and N.

Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Spectroscopy as a Forensic Method to Determine the Composition of Inks Used to Print the United States One-cent Blue Benjamin Franklin Postage Stamps of the 19th Century.

PubMed

Brittain, Harry G

2016-01-01

Through the combined use of infrared (IR) absorption spectroscopy and attenuated total reflectance (ATR) sampling, the composition of inks used to print the many different types of one-cent Benjamin Franklin stamps of the 19th century has been established. This information permits a historical evaluation of the formulations used at various times, and also facilitates the differentiation of the various stamps from each other. In two instances, the ink composition permits the unambiguous identification of stamps whose appearance is identical, and which (until now) have only been differentiated through estimates of the degree of hardness or softness of the stamp paper, or through the presence or absence of a watermark in the paper. In these instances, the use of ATR Fourier transform infrared spectroscopy (FT-IR) spectroscopy effectively renders irrelevant two 100-year-old practices of stamp identification. Furthermore, since the use of ATR sampling makes it possible to obtain the spectrum of a stamp still attached to its cover, it is no longer necessary to identify these blue Franklin stamps using their cancellation dates. © The Author(s) 2015.

Modulated near-field spectral extraction of broadband mid-infrared signals with a ceramic light source.

PubMed

Ishikawa, Michio; Katsura, Makoto; Nakashima, Satoru; Aizawa, Kento; Inoue, Tsutomu; Okamura, Hidekazu; Ikemoto, Yuka

2011-06-20

In order to obtain broadband near-field infrared (IR) spectra, a Fourier-transform IR spectrometer (FT-IR) and a ceramic light source were used with a scattering-type scanning near-field optical microscope (s-SNOM). To suppress the background (far-field) scattering, the distance between the scattering probe and the sample was modulated with frequency Ω by a piezo-electric actuator, and the Ω component was extracted from the signal with a lock-in detection. With Ω=30 kHz, a peak-to-peak modulation amplitude of 198 nm, and a probe with smooth surface near the tip, broadband near-field IR spectra could be obtained in the 1200-2500 cm(-1).

Rapid discrimination of Panax notogeinseng of different grades by FT-IR and 2DCOS-IR

NASA Astrophysics Data System (ADS)

Ma, Fang; Chen, Jian-bo; Wu, Xian-xue; Zhou, Qun; Sun, Su-qin

2016-11-01

The herbal material of Notoginseng (the root of Panax notoginseng) is sold by "Tou" (the number of Notoginseng in every 500 g) to distinguish the grade. Normally the better quality, the few number of the "Tou" and the size of Notoginseng is bigger. In this study, three grades of Notoginseng harvested from Yunnan province were discriminated and identified by Fourier transform infrared spectroscopy (FT-IR) and two-dimensional correlation infrared spectroscopy (2DCOS-IR)). The correlation coefficient of IR spectra between the three grades of Notoginseng and starch are greater than 0.95 in the range of 1300-800 cm-1, means the main compositions of Notoginseng are starch polysaccharide. Also, when the size of Notoginseng is bigger, it may contain more polysaccharide. There is no difference in range of 815-1000 cm-1 of the 2DCOS-IR synchronous spectra of the three grades means polysaccharides possess good thermal stability. In the range of 1200-1300 cm-1 shows the inverse ration between the thermal sensitivity of C-O and the number of "Tou". Combination with the 2DCOS-IR asynchronous spectra, the response speed of amino acid (1640 cm-1) on the thermal perturbation is the fastest, followed by nitrate (1384 cm-1); the response speed of polysaccharides (1079 cm-1) is the slowest. The result proved that the 2DCOS-IR could discriminate different grades of Notoginseng.

Identification Of Fatty Acid Isomers By Gas Chromatography / Matrix Isolation / Fourier Transform Infrared Spectroscopy

NASA Astrophysics Data System (ADS)

Mossoba, Magdi M.; McDonald, Richard E.; Chen, Jo-Yun T.; Page, Samuel W.

1989-12-01

Geometric and positional isomers of fatty acid methyl esters (FAME) derived from hydrogenated soybean oil and margarines were separated by silver nitrate-thin layer chromatography (AgNO3-TLC) followed by capillary gas chromatography (GC) and identified by matrix isolation / Fourier transform infrared (MI/FTIR) spectroscopyi,2. Because of the high specificity of the MI technique, it was possible to distinguish between different 18-carbon aliphatic chains of FAME positional isomers with cis or trans configuration, and to determine their degree of unsaturation. For the first time mid-IR spectra were observed for methylene-interrupted or isolated trans, trans or cis/ trans C18 FAME positional isomers. These spectra could be readily differentiated based on unique MI/FTIR spectral characteristics.

Differentiation of five species of Danggui raw materials by FTIR combined with 2D-COS IR

NASA Astrophysics Data System (ADS)

Li, Jian-Rui; Sun, Su-Qin; Wang, Xiao-Xiao; Xu, Chang-Hua; Chen, Jian-Bo; Zhou, Qun; Lu, Guang-Hua

2014-07-01

Five herbs named as Chinese Danggui (CDG), Japanese Danggui (JDG), Korea Danggui (KDG), Lovage root (LR) and Angelica root (AR) are widely and confusedly used in eastern and western countries owing to their homonym. These herbs come from different plant species resulting in the variety of bioactive components and medical efficacy. A method combing tri-step IR macro-fingerprinting techniques with statistical pattern recognition was therefore employed discriminate the five herbs in order to assure their genuineness. A total of 26 samples were collected and identified by conventional Fourier transform infrared (FTIR) spectroscopy, second derivative infrared (SD-IR) spectroscopy and two-dimensional correlation infrared (2D-COS IR) spectroscopy. CDG and KDG were easily differentiated from others herbs by FTIR and SD-IR spectra. The characteristic peaks of CDG were located at 1068, 1051, 990, 909 and 867 cm-1, whilst KDG contained the peaks located at 1628, 1565, 1392, 1232 and 1136 cm-1. By 2D-COS IR spectra, the bands in the range of 950-1110 cm-1 could be a characteristic range to identify the five herbs. There were six auto-peaks located at 978, 991, 1028 (strongest), 1061, 1071 and 1097 cm-1 for CDG, six auto-peaks at 975, 991, 1026, 1053, 1070 (strongest) and 1096 cm-1 for KDG, five auto-peaks at 970, 1009, 1037, 1070 and 1096 (strongest) cm-1 for JDG, five auto-peaks at 973 (strongest), 1009, 1033, 1072 and 1099 cm-1 for LR, and five auto-peaks at 974 (strongest), 1010, 1033, 1072 and 1099 cm-1 for AR. Classification analysis of FTIR showed that these species located in different clusters. The results indicate the tri-step infrared macro-fingerprinting combines with principle component analysis (PCA) is suitable to rapidly and nondestructively differentiate these herbs.

MULTISPECTRAL IDENTIFICATION OF POTENTIALLY HAZARDOUS BYPRODUCTS OF OZONATION AND CHLORINATION - PART I: STUDIES OF CHROMATOGRAPHIC AND SPECTROSCOPIC PROPERTIES OF MX

EPA Science Inventory

The gas chromatographic (GC) and Fourier transform infrared and mass spectroscopic (FT-IR and MS, respectively) properties of (Z)-2-chloro-3-(dichloromethyl)4-oxobutenoic acid (MX) (a highly mutagenic byproduct of drinking water chlorination) and several related compounds were st...

Cotton fiber cell wall development for three cultivars: an Fourier transform infrared spectroscopy examination

USDA-ARS?s Scientific Manuscript database

An examination of FT-IR vibrational band development in spectra of cotton fiber at different developmental dates (18 – 40 days post-anthesis; DPA) will be presented in this talk. Results from three cotton cultivars will be presented. Two of the cultivars are nearly identical genetic lines, which ha...

Modification of vital wheat gluten with phosphoric acid to produce high free solution capacity

USDA-ARS?s Scientific Manuscript database

Wheat gluten reacts with phosphoric acid in the presence of urea to produce natural superabsorbent gels. Fourier Transform Infra-red (FT-IR) spectroscopy and two-dimensional gel electrophoresis (2DE) reveal chemical changes from the reaction. Temperatures above 120°C and dry conditions create the op...

Fourier-transformed infrared breath testing after ingestion of technical alcohol.

PubMed

Laakso, Olli; Haapala, Matti; Pennanen, Teemu; Kuitunen, Tapio; Himberg, Jaakko-Juhani

2007-07-01

The study aim was to evaluate the feasibility of a Fourier-transformed infrared (FT-IR) analyzer for out-of-laboratory use by screening the exhalations of inebriated individuals, and to determine analysis quality using common breath components and solvents. Each of the 35 inebriated participants gave an acceptable sample. Because of the metabolism of 2-propanol, the subjects exhaled high concentrations of acetone in addition to ethanol. Other volatile ingredients of technical ethanol products (methyl ethyl ketone, methyl isobutyl ketone, and 2-propanol) were also detected. The lower limits of quantification for the analyzed components ranged from 1.7 to 12 microg/L in simulated breath samples. The bias was +/-2% for ethanol and -11% for methanol. Within-day and between-day coefficients of variation were <1% for ethanol and <4% for methanol. The bias of ethanol and methanol analyses due to coexisting solvents ranged from -0.8 to +2.2% and from -5.6 to +2.9%, respectively. The FT-IR method proved suitable for use outside the laboratory and fulfilled the quality criteria for analysis of solvents in breath.

Liquid chromatography/Fourier transform IR spectrometry interface flow cell

DOEpatents

Johnson, Charles C.; Taylor, Larry T.

1986-01-01

A zero dead volume (ZDV) microbore high performance liquid chromatography (.mu.HPLC)/Fourier transform infrared (FTIR) interface flow cell includes an IR transparent crystal having a small diameter bore therein through which a sample liquid is passed. The interface flow cell further includes a metal holder in combination with a pair of inner, compressible seals for directly coupling the thus configured spectrometric flow cell to the outlet of a .mu.HPLC column end fitting to minimize the transfer volume of the effluents exiting the .mu.HPLC column which exhibit excellent flow characteristics due to the essentially unencumbered, open-flow design. The IR beam passes transverse to the sample flow through the circular bore within the IR transparent crystal, which is preferably comprised of potassium bromide (KBr) or calcium fluoride (CaF.sub.2), so as to minimize interference patterns and vignetting encountered in conventional parallel-plate IR cells. The long IR beam pathlength and lensing effect of the circular cross-section of the sample volume in combination with the refractive index differences between the solvent and the transparent crystal serve to focus the IR beam in enhancing sample detection sensitivity by an order of magnitude.

Liquid chromatography/Fourier transform IR spectrometry interface flow cell

DOEpatents

Johnson, C.C.; Taylor, L.T.

1985-01-04

A zero dead volume (ZDV) microbore high performance liquid chromatography (..mu.. HPLC)/Fourier transform infrared (FTIR) interface flow cell includes an IR transparent crystal having a small diameter bore therein through which a sample liquid is passed. The interface flow cell further includes a metal holder in combination with a pair of inner, compressible seals for directly coupling the thus configured spectrometric flow cell to the outlet of a ..mu.. HPLC column end fitting to minimize the transfer volume of the effluents exiting the ..mu.. HPLC column which exhibit excellent flow characteristics due to the essentially unencumbered, open-flow design. The IR beam passes transverse to the sample flow through the circular bore within the IR transparent crystal, which is preferably comprised of potassium bromide (KBr) or calcium fluoride (CaF/sub 2/), so as to minimize interference patterns and vignetting encountered in conventional parallel-plate IR cells. The long IR beam pathlength and lensing effect of the circular cross-section of the sample volume in combination with the refractive index differences between the solvent and the transparent crystal serve to focus the IR beam in enhancing sample detection sensitivity by an order of magnitude.

Remote Skin Tissue Diagnostics In Vivo By Fiber Optic Evanescent Wave Fourier Transform Infrared (FEW-FTIR) Spectroscopy

NASA Astrophysics Data System (ADS)

Kolyakov, Sergei; Afanasyeva, Natalia; Bruch, Reinhard; Afanasyeva, Natalia

1998-05-01

The new method of fiber optical evanescent wave Fourier transform infrared (FEW-FTIR) spectroscopy has been applied to the diagnostics of normal skin tissue, as well as precancerous and cancerous conditions. The FEW-FTIR technique is nondestructive and sensitive to changes of vibrational spectra in the IR region, without heating and damaging human and animal skin tissue. Therefore this method and technique is an ideal diagnostic tool for tumor and cancer characterization at an early stage of development on a molecular level. The application of fiber optic technology in the middle infrared (MIR) region is relatively inexpensive and can be adapted easily to any commercially available tabletop FTIR spectrometers. This method of diagnostics is fast (several seconds), and can be applied to many fields. Noninvasive medical diagnostics of skin cancer and other skin diseases in vivo, ex vivo, and in vitro allow for the development of convenient, remote clinical applications in dermatology and related fields. The spectral variations from normal to pathological skin tissue and environmental influence on skin have been measured.

Rapid prediction of phenolic compounds and antioxidant activity of Sudanese honey using Raman and Fourier transform infrared (FT-IR) spectroscopy.

PubMed

Tahir, Haroon Elrasheid; Xiaobo, Zou; Zhihua, Li; Jiyong, Shi; Zhai, Xiaodong; Wang, Sheng; Mariod, Abdalbasit Adam

2017-07-01

Fourier transform infrared with attenuated total reflectance (FTIR-ATR) and Raman spectroscopy combined with partial least square regression (PLSR) were applied for the prediction of phenolic compounds and antioxidant activity in honey. Standards of catechin, syringic, vanillic, and chlorogenic acids were used for the identification and quantification of the individual phenolic compounds in six honey varieties using HPLC-DAD. Total antioxidant activity (TAC) and ferrous chelating capacity were measured spectrophotometrically. For the establishment of PLSR model, Raman spectra with Savitzky-Golay smoothing in wavenumber region 1500-400cm -1 was used while for FTIR-ATR the wavenumber regions of 1800-700 and 3000-2800cm -1 with multiplicative scattering correction (MSC) and Savitzky-Golay smoothing were used. The determination coefficients (R 2 ) were ranged from 0.9272 to 0.9992 for Raman while from 0.9461 to 0.9988 for FTIT-ART. The FTIR-ATR and Raman demonstrated to be simple, rapid and nondestructive methods to quantify phenolic compounds and antioxidant activities in honey. Copyright © 2017 Elsevier Ltd. All rights reserved.

Modeling Microalgal Biosediment Formation Based on Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Monitoring.

PubMed

Ogburn, Zachary L; Vogt, Frank

2018-03-01

With increasing amounts of anthropogenic pollutants being released into ecosystems, it becomes ever more important to understand their fate and interactions with living organisms. Microalgae play an important ecological role as they are ubiquitous in marine environments and sequester inorganic pollutants which they transform into organic biomass. Of particular interest in this study is their role as a sink for atmospheric CO 2 , a greenhouse gas, and nitrate, one cause of harmful algal blooms. Novel chemometric hard-modeling methodologies have been developed for interpreting phytoplankton's chemical and physiological adaptations to changes in their growing environment. These methodologies will facilitate investigations of environmental impacts of anthropogenic pollutants on chemical and physiological properties of marine microalgae (here: Nannochloropsis oculata). It has been demonstrated that attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy can gain insights into both and this study only focuses on the latter. From time-series of spectra, the rate of microalgal biomass settling on top of a horizontal ATR element is derived which reflects several of phytoplankton's physiological parameters such as growth rate, cell concentrations, cell size, and buoyancy. In order to assess environmental impacts on such parameters, microalgae cultures were grown under 25 different chemical scenarios covering 200-600 ppm atmospheric CO 2 and 0.35-0.75 mM dissolved NO 3 - . After recording time-series of ATR FT-IR spectra, a multivariate curve resolution-alternating least squares (MCR-ALS) algorithm extracted spectroscopic and time profiles from each data set. From the time profiles, it was found that in the considered concentration ranges only NO 3 - has an impact on the cells' physiological properties. In particular, the cultures' growth rate has been influenced by the ambient chemical conditions. Thus, the presented spectroscopic + chemometric methodology enables investigating the link between chemical conditions in a marine ecosystem and their consequences for phytoplankton living in it.

Near-field photothermal microspectroscopy for adult stem-cell identification and characterization.

PubMed

Grude, Olaug; Hammiche, Azzedine; Pollock, Hubert; Bentley, Adam J; Walsh, Michael J; Martin, Francis L; Fullwood, Nigel J

2007-12-01

The identification of stem cells in adult tissue is a challenging problem in biomedicine. Currently, stem cells are identified by individual epitopes, which are generally tissue specific. The discovery of a stem-cell marker common to other adult tissue types could open avenues in the development of therapeutic stem-cell strategies. We report the use of the novel technique of Fourier transform infrared near-field photothermal microspectroscopy (FTIR-PTMS) for the characterization of stem cells, transit amplifying (TA) cells and terminally differentiated (TD) cells in the corneal epithelium. Principal component analysis (PCA) data demonstrate excellent discrimination of cell type by spectra. PCA in combination with linear discriminant analysis (PCA-LDA) shows that FTIR-PTMS very effectively discriminates between the three cell populations. Statistically significant differences above the 99% confidence level between IR spectra from stem cells and TA cells suggest that nucleic acid conformational changes are an important component of the differences between spectral data from the two cell types. FTIR-PTMS is a new addition to existing spectroscopy methods based on the concept of interfacing a conventional FTIR spectrometer with an atomic force microscope equipped with a near-field thermal sensing probe. FTIR-PTMS spectroscopy currently has spatial resolution that is similar to that of diffraction-limited optical detection FTIR spectroscopy techniques, but as a near-field probing technique has considerable potential for further improvement. Our work also suggests that FTIR-PTMS is potentially more sensitive than synchrotron radiation FTIR spectroscopy for some applications. Microspectroscopy techniques like FTIR-PTMS provide information about the entire molecular composition of cells, in contrast to epitope recognition that only considers the presence or absence of individual molecules. Our results with FTIR-PTMS on corneal stem cells are promising for the potential development of an IR spectral fingerprint for stem cells.

Large-scale synthesis of a novel tri(8-hydroxyquioline) aluminum nanostructure.

PubMed

Tian, Xike; Fei, Jinbo; Pi, Zhenbang; Yang, Chao; Xiao, Zhidong; Zhang, Lide

2006-08-01

A novel tri(8-hydroxyquioline) aluminum (AlQ3) nanostructure was prepared on large scale at low cost by low-temperature physical vapor deposition (PVD). The morphologies, the chemical bondings, and photoluminescence of the AlQ3 nanostructure were investigated by environmental scanning electronic microscopy (ESEM), Fourier transform infrared spectrum (FT-IR), and photoluminescence (PL) spectra, respectively. The AlQ3 nanostructure was composed of micro-sphere with nanowire-cluster growing on the surface. The diameter of micro-sphere and nanowire were about 5 microm and 80 nm, respectively. FT-IR results indicated that the AlQ3 molecule had a strong thermal stability under research conditions. The growth mechanism of the novel nanostructure was discussed. The novel organic nanostructure would be believed to attractive building field-emission devices and other optical devices.

Analysis of pure and malachite green doped polysulfone sample using FT-IR technique

NASA Astrophysics Data System (ADS)

Nayak, Rashmi J.; Khare, P. K.; Nayak, J. G.

2018-05-01

The sample of pure and malachite green doped Polysulfone in the form of foil was prepared by isothermal immersion technique. For the preparation of pure sample 4 gm of Polysulfone was dissolved in 50 ml of Dimethyl farmamide (DMF) solvent, while for the preparation of doped sample 10 mg, 50 mg and 100 mg Malachite Green was mixed with 4 gm of Polysulfone respectively. For the study of structural characterization of these pure and doped sample, Fourier Transform Infra-Red Spectroscopy (FT-IR) technique was used. This study shows that the intensity of transmittance decreases as the ratio of doping increases in pure polysulfone. The reduction in intensity of transmittance is clearly apparent in the present case more over the bands were broader which indicates towards charge transfer interaction between the donar and acceptor molecule.

DFT simulation, quantum chemical electronic structure, spectroscopic and structure-activity investigations of 4-acetylpyridine

NASA Astrophysics Data System (ADS)

Atilgan, A.; Yurdakul, Ş.; Erdogdu, Y.; Güllüoğlu, M. T.

2018-06-01

The spectroscopic (UV-Vis and infrared), structural and some electronic property observations of the 4-acetylpyridine (4-AP) were reported, which are investigated by using some spectral methods and DFT calculations. FT-IR spectra were obtained for 4-AP at room temperature in the region 4000 cm-1- 400 cm-1. In the DFT calculations, the B3LYP functional with 6-311G++G(d,p) basis set was applied to carry out the quantum mechanical calculations. The Fourier Transform Infrared (FT-IR) and FT-Raman spectra were interpreted by using of normal coordinate analysis based on scaled quantum mechanical force field. The present work expands our understanding of the both the vibrational and structural properties as well as some electronic properties of the 4-AP by means of the theoretical and experimental methods.

Insights into the activation mechanism of calcium ions on the sericite surface: A combined experimental and computational study

NASA Astrophysics Data System (ADS)

Hu, Yuehua; He, Jianyong; Zhang, Chenhu; Zhang, Chenyang; Sun, Wei; Zhao, Dongbo; Chen, Pan; Han, Haisheng; Gao, Zhiyong; Liu, Runqing; Wang, Li

2018-01-01

The adsorption behaviors and the activation mechanism of calcium ions (Ca2+) on sericite surface have been investigated by Zeta potential measurements, Fourier transform infrared spectroscopy (FT-IR), Micro-flotation tests and First principle calculations. Zeta potential tests results show that the sericite surface potential increases due to the adsorption of calcium ions on the surface. Micro-flotation tests demonstrate that sericite recovery remarkably rise by 10% due to the calcium ions activation on sericite surface. However, the characteristic adsorption bands of calcium oleate do not appear in the FT-IR spectrum, suggesting that oleate ions just physically adsorb on the sericite surface. The first principle calculations based on the density functional theory (DFT) further reveals the microscopic adsorption mechanism of calcium ions on the sericite surface before and after hydration.

Synthesis and characterization of starch-poly(methyl acrylate) graft copolymers using horseradish peroxidase.

PubMed

Wang, Su; Wang, Qiang; Fan, Xuerong; Xu, Jin; Zhang, Ying; Yuan, Jiugang; Jin, Heling; Cavaco-Paulo, Artur

2016-01-20

Horseradish peroxidase (HRP)-mediated graft polymerization in the presence of hydrogen peroxide (H2O2) and acetylacetone (Acac) has been successfully applied to the synthesis of starch-poly(methyl acrylate) (PMA). The graft copolymer was characterized by Fourier transform infrared (FT-IR), elemental analysis, nuclear magnetic resonance ((1)H NMR and (13)C NMR), and differential scanning calorimetry (DSC). FT-IR, elemental analysis and NMR confirmed that methyl acrylate (MA) was grafted onto starch successfully. DSC results showed the graft reaction had changed the crystalline regions of the gelatinized starch. The effects of pH, MA content, HRP dosage, incubation temperature and time on grafting percentage (GP) and grafting efficiency (GE) were also investigated. The GP and GE under optimal conditions reached 30.21% and 45.13%, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR FT-IR) Applied to Study the Distribution of Ink Components in Printed Newspapers.

PubMed

Gómez, Nuria; Molleda, Cristina; Quintana, Ester; Carbajo, José M; Rodríguez, Alejandro; Villar, Juan C

2016-09-01

A new method was developed to study how the oil and cyan pigments of cold-set ink are distributed in newspaper thickness. The methodology involved laboratory printing followed by delamination of the printed paper. The unprinted side, printed side, and resulting layers were analyzed using attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR). Three commercial newspapers and black and cyan cold-set inks were chosen for the study. Attenuated total reflection Fourier transform infrared spectroscopy enabled the proportion of oil and cyan pigment on the printed surface and throughout the sheet thickness to be measured. Oil percentage was evaluated as the area increment of the region from 2800 cm(-1) to 3000 cm(-1) The relative amount of cyan pigment was determined as the area of the absorption band at 730 cm(-1) The ink oil was found mainly below half the paper thickness, whereas the pigment was detected at the layers closer to the printed surface, at a depth penetration of less than 15 µm (20% of thickness). Distribution of these two components in paper thickness depended on the type of cold-set ink, the amount of ink transferred, and the newspaper properties. © The Author(s) 2016.

A Comparison of Analytical and Data Preprocessing Methods for Spectral Fingerprinting

PubMed Central

LUTHRIA, DEVANAND L.; MUKHOPADHYAY, SUDARSAN; LIN, LONG-ZE; HARNLY, JAMES M.

2013-01-01

Spectral fingerprinting, as a method of discriminating between plant cultivars and growing treatments for a common set of broccoli samples, was compared for six analytical instruments. Spectra were acquired for finely powdered solid samples using Fourier transform infrared (FT-IR) and Fourier transform near-infrared (NIR) spectrometry. Spectra were also acquired for unfractionated aqueous methanol extracts of the powders using molecular absorption in the ultraviolet (UV) and visible (VIS) regions and mass spectrometry with negative (MS−) and positive (MS+) ionization. The spectra were analyzed using nested one-way analysis of variance (ANOVA) and principal component analysis (PCA) to statistically evaluate the quality of discrimination. All six methods showed statistically significant differences between the cultivars and treatments. The significance of the statistical tests was improved by the judicious selection of spectral regions (IR and NIR), masses (MS+ and MS−), and derivatives (IR, NIR, UV, and VIS). PMID:21352644

Screening of exhaled breath by low-resolution multicomponent FT-IR spectrometry in patients attending emergency departments.

PubMed

Laakso, Olli; Haapala, Matti; Kuitunen, Tapio; Himberg, Jaakko-Juhani

2004-03-01

Interest in noninvasive methods for disease diagnosis is increasing. In this study, we tested the utility and potential of a portable Fourier transform infrared (FT-IR) multicomponent analyzer in the emergency rooms (ERs) of two Finnish hospitals. Major detected breath volatiles in this population were ethanol, carbon monoxide, methane, and acetone, in addition to carbon dioxide and water. The analysis of breath revealed an ethanol concentration of over 25 ppm (0.1 g/L in blood) in 56 out of 589 patients (9.5%). During nightshifts the proportion was 30% for all and 63% for trauma patients. Five-hundred eighty-four patients had measurable carbon monoxide in their breath. A breath carbon monoxide of over 4 ppm (4.4 micro g/L) differentiated smokers from nonsmokers. Methane over 2 ppm (1.3 micro g/L) was detected in the breath of 32% of the participants. Methane concentration was higher among aged patients. Two-hundred ninety-eight participants had detectable acetone in their breath. Elevated exhaled acetone [10-76 ppm (23-75 micro g/L)] was detected in 10 patients. The FT-IR method proved functional in the ER setting. A major advantage over blood sampling was fast and easy analysis performed by nonlaboratory personnel.

Effect of microwave treatment on structure of binders based on sodium carboxymethyl starch: FT-IR, FT-Raman and XRD investigations

NASA Astrophysics Data System (ADS)

Kaczmarska, Karolina; Grabowska, Beata; Spychaj, Tadeusz; Zdanowicz, Magdalena; Sitarz, Maciej; Bobrowski, Artur; Cukrowicz, Sylwia

2018-06-01

The paper deals with the influence of the microwave treatment on sodium carboxymethyl starch (CMS-Na) applied as a binder for moulding sands. The Fourier transformation infrared spectrometry (FT-IR), Raman spectroscopy (FT-Raman) and XRD analysis data of native potato starch and three different carboxymethyl starches (CMS-Na) with various degree of substitution (DS) before and after exposition to microwave radiation have been compared. FT-IR studies showed that polar groups present in CMS-Na structure take part in the formation of new hydrogen bonds network after water evaporation. However, these changes depend on DS value of the modified starch. The FT-Raman study confirmed that due to the impact on the samples by microwave, the changes of intensity in the characteristic bands associated with the crystalline regions in the sample were noticed. The X-ray diffraction data for microwave treated CMS-Na samples have been compared with the diffractograms of initial materials and analysis of XRD patterns confirmed that microwave-treated samples exhibit completely amorphous structure. Analysis of structural changes allows to state that the binding of sand grains in moulding sand with CMS-Na polymeric binder consists in the formation of hydrogen bonds networks (physical cross-linking).

A new tridentate Schiff base Cu(II) complex: synthesis, experimental and theoretical studies on its crystal structure, FT-IR and UV-Visible spectra.

PubMed

Saheb, Vahid; Sheikhshoaie, Iran; Setoodeh, Nasim; Rudbari, Hadi Amiri; Bruno, Giuseppe

2013-06-01

A new Cu(II) complex [Cu(L)(NCS)] has been synthesized, using 1-(N-salicylideneimino)-2-(N,N-methyl)-aminoethane as tridentate ONN donor Schiff base ligand (HL). The dark green crystals of the compound are used for single-crystal X-ray analysis and measuring Fourier Transform Infrared (FT-IR) and UV-Visible spectra. Electronic structure calculations at the B3LYP and MP2 levels of theory are performed to optimize the molecular geometry and to calculate the UV-Visible and FT-IR spectra of the compound. Vibrational assignments and analysis of the fundamental modes of the compound are performed. Time-dependent density functional theory (TD-DFT) method is used to calculate the electronic transitions of the complex. A scaling factor of 1.015 is obtained for vibrational frequencies computed at the B3LYP level using basis sets 6-311G(d,p). It is found that solvent has a profound effect on the electronic absorption spectrum. The UV-Visible spectrum of the complex recorded in DMSO and DMF solution can be correctly predicted by a model in which DMSO and DMF molecules are coordinated to the central Cu atom via their oxygen atoms. Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of microwave treatment on structure of binders based on sodium carboxymethyl starch: FT-IR, FT-Raman and XRD investigations.

PubMed

Kaczmarska, Karolina; Grabowska, Beata; Spychaj, Tadeusz; Zdanowicz, Magdalena; Sitarz, Maciej; Bobrowski, Artur; Cukrowicz, Sylwia

2018-06-15

The paper deals with the influence of the microwave treatment on sodium carboxymethyl starch (CMS-Na) applied as a binder for moulding sands. The Fourier transformation infrared spectrometry (FT-IR), Raman spectroscopy (FT-Raman) and XRD analysis data of native potato starch and three different carboxymethyl starches (CMS-Na) with various degree of substitution (DS) before and after exposition to microwave radiation have been compared. FT-IR studies showed that polar groups present in CMS-Na structure take part in the formation of new hydrogen bonds network after water evaporation. However, these changes depend on DS value of the modified starch. The FT-Raman study confirmed that due to the impact on the samples by microwave, the changes of intensity in the characteristic bands associated with the crystalline regions in the sample were noticed. The X-ray diffraction data for microwave treated CMS-Na samples have been compared with the diffractograms of initial materials and analysis of XRD patterns confirmed that microwave-treated samples exhibit completely amorphous structure. Analysis of structural changes allows to state that the binding of sand grains in moulding sand with CMS-Na polymeric binder consists in the formation of hydrogen bonds networks (physical cross-linking). Copyright © 2018 Elsevier B.V. All rights reserved.

Vibrational spectroscopy for imaging single microbial cells in complex biological samples

DOE PAGES

Harrison, Jesse P.; Berry, David

2017-04-13

Here, vibrational spectroscopy is increasingly used for the rapid and non-destructive imaging of environmental and medical samples. Both Raman and Fourier-transform infrared (FT-IR) imaging have been applied to obtain detailed information on the chemical composition of biological materials, ranging from single microbial cells to tissues. Due to its compatibility with methods such as stable isotope labeling for the monitoring of cellular activities, vibrational spectroscopy also holds considerable power as a tool in microbial ecology. Chemical imaging of undisturbed biological systems (such as live cells in their native habitats) presents unique challenges due to the physical and chemical complexity of themore » samples, potential for spectral interference, and frequent need for real-time measurements. This Mini Review provides a critical synthesis of recent applications of Raman and FT-IR spectroscopy for characterizing complex biological samples, with a focus on developments in single-cell imaging. We also discuss how new spectroscopic methods could be used to overcome current limitations of singlecell analyses. Given the inherent complementarity of Raman and FT-IR spectroscopic methods, we discuss how combining these approaches could enable us to obtain new insights into biological activities either in situ or under conditions that simulate selected properties of the natural environment.« less

Vibrational spectroscopy for imaging single microbial cells in complex biological samples

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

Harrison, Jesse P.; Berry, David

Here, vibrational spectroscopy is increasingly used for the rapid and non-destructive imaging of environmental and medical samples. Both Raman and Fourier-transform infrared (FT-IR) imaging have been applied to obtain detailed information on the chemical composition of biological materials, ranging from single microbial cells to tissues. Due to its compatibility with methods such as stable isotope labeling for the monitoring of cellular activities, vibrational spectroscopy also holds considerable power as a tool in microbial ecology. Chemical imaging of undisturbed biological systems (such as live cells in their native habitats) presents unique challenges due to the physical and chemical complexity of themore » samples, potential for spectral interference, and frequent need for real-time measurements. This Mini Review provides a critical synthesis of recent applications of Raman and FT-IR spectroscopy for characterizing complex biological samples, with a focus on developments in single-cell imaging. We also discuss how new spectroscopic methods could be used to overcome current limitations of singlecell analyses. Given the inherent complementarity of Raman and FT-IR spectroscopic methods, we discuss how combining these approaches could enable us to obtain new insights into biological activities either in situ or under conditions that simulate selected properties of the natural environment.« less

On the Identification of Rayon/Viscose as a Major Fraction of Microplastics in the Marine Environment: Discrimination between Natural and Manmade Cellulosic Fibers Using Fourier Transform Infrared Spectroscopy

PubMed Central

Comnea-Stancu, Ionela Raluca; Wieland, Karin; Ramer, Georg; Schwaighofer, Andreas

2016-01-01

This work was sparked by the reported identification of man-made cellulosic fibers (rayon/viscose) in the marine environment as a major fraction of plastic litter by Fourier transform infrared (FT-IR) transmission spectroscopy and library search. To assess the plausibility of such findings, both natural and man-made fibers were examined using FT-IR spectroscopy. Spectra acquired by transmission microscopy, attenuated total reflection (ATR) microscopy, and ATR spectroscopy were compared. Library search was employed and results show significant differences in the identification rate depending on the acquisition method of the spectra. Careful selection of search parameters and the choice of spectra acquisition method were found to be essential for optimization of the library search results. When using transmission spectra of fibers and ATR libraries it was not possible to differentiate between man-made and natural fibers. Successful differentiation of natural and man-made cellulosic fibers has been achieved for FT-IR spectra acquired by ATR microscopy and ATR spectroscopy, and application of ATR libraries. As an alternative, chemometric methods such as unsupervised hierarchical cluster analysis, principal component analysis, and partial least squares-discriminant analysis were employed to facilitate identification based on intrinsic relationships of sample spectra and successful discrimination of the fiber type could be achieved. Differences in the ATR spectra depending on the internal reflection element (Ge versus diamond) were observed as expected; however, these did not impair correct classification by chemometric analysis. Moreover, the effects of different levels of humidity on the IR spectra of natural and man-made fibers were investigated, too. It has been found that drying and re-humidification leads to intensity changes of absorption bands of the carbohydrate backbone, but does not impair the identification of the fiber type by library search or cluster analysis. PMID:27650982

Effects of Particle Size on the Attenuated Total Reflection Spectrum of Minerals.

PubMed

Udvardi, Beatrix; Kovács, István J; Fancsik, Tamás; Kónya, Péter; Bátori, Miklósné; Stercel, Ferenc; Falus, György; Szalai, Zoltán

2017-06-01

This study focuses on particle size effect on monomineralic powders recorded using attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy. Six particle size fractions of quartz, feldspar, calcite, and dolomite were prepared (<2, 2-4, 4-8, 8-16, 16-32, and 32-63 µm). It is found that the width, intensity, and area of bands in the ATR FT-IR spectra of minerals have explicit dependence on the particle size. As particle size increases, the intensity and area of IR bands usually decrease while the width of bands increases. The band positions usually shifted to higher wavenumbers with decreasing particle size. Infrared spectra of minerals are the most intensive in the particle size fraction of 2-4 µm. However, if the particle size is very small (<2 µm), due to the wavelength and penetration depth of the IR light, intensity decreases. Therefore, the quantity of very fine-grained minerals may be underestimated compared to the coarser phases. A nonlinear regression analysis of the data indicated that the average coefficients and indices of the power trend line equation imply a very simplistic relationship between median particle diameter and absorbance at a given wavenumber. It is concluded that when powder samples with substantially different particle size are compared, as in regression analysis for modal predictions using ATR FT-IR, it is also important to report the grain size distribution or surface area of samples. The band area of water (3000-3620 cm -1 ) is similar in each mineral fraction, except for the particles below 2 µm. It indicates that the finest particles could have disproportionately more water adsorbed on their larger surface area. Thus, these higher wavenumbers of the ATR FT-IR spectra may be more sensitive to this spectral interference if the number of particles below 2 µm is considerable. It is also concluded that at least a proportion of the moisture could be very adhesive to the particles due to the band shift towards lower wavenumbers in the IR range of 3000-3620 cm -1 .

Imaging of lipids in atherosclerotic lesion in aorta from ApoE/LDLR-/- mice by FT-IR spectroscopy and Hierarchical Cluster Analysis.

PubMed

P Wrobel, Tomasz; Mateuszuk, Lukasz; Chlopicki, Stefan; Malek, Kamilla; Baranska, Malgorzata

2011-12-21

Spectroscopy-based approaches can provide an insight into the biochemical composition of a tissue sample. In the present work Fourier transform infrared (FT-IR) spectroscopy was used to develop a reliable methodology to study the content of free fatty acids, triglycerides, cholesteryl esters as well as cholesterol in aorta from mice with atherosclerosis (ApoE/LDLR(-/-) mice). In particular, distribution and concentration of palmitic, oleic and linoleic acid derivatives were analyzed. Spectral analysis of pure compounds allowed for clear discrimination between free fatty acids and other similar moieties based on the carbonyl band position (1699-1710 cm(-1) range). In order to distinguish cholesteryl esters from triglycerides a ratio of carbonyl band to signal at 1010 cm(-1) was used. Imaging of lipids in atherosclerotic aortic lesions in ApoE/LDLR(-/-) mice was followed by Hierarchical Cluster Analysis (HCA). The aorta from C57Bl/6J control mice (fed with chow diet) was used for comparison. The measurements were completed with an FT-IR spectrometer equipped with a 128 × 128 FPA detector. In cross-section of aorta from ApoE/LDLR(-/-) mice a region of atherosclerotic plaque was clearly identified by HCA, which was later divided into 2 sub-regions, one characterized by the higher content of cholesterol, while the other by higher contents of cholesteryl esters. HCA of tissues deposited on normal microscopic glass, hence limited to the 2200-3800 cm(-1) spectral range, also identified a region of atherosclerotic plaque. Importantly, this region correlates with the area stained by standard histological staining for atherosclerotic plaque (Oil Red O). In conclusion, the use of FT-IR and HCA may provide a novel tool for qualitative and quantitative analysis of contents and distribution of lipids in atherosclerotic plaque.

Application of spectroscopic techniques for the study of the surface changes in poplar wood and possible implications in conservation of wooden artefacts

NASA Astrophysics Data System (ADS)

Pelosi, C.; Agresti, G.; Calienno, L.; Lo Monaco, A.; Picchio, R.; Santamaria, U.; Vinciguerra, V.

2013-05-01

The aim of this work is to study the surface modifications of poplar (Populus spp.) wood by reflectance spectrophotometry and Fourier Transform Infrared (FT-IR) spectroscopy in order to understand the mechanisms that cause the changes and to suggest possible solutions to avoid the degradation phenomena. Since colour changes on wood surfaces are due to photo degradation of its chemical constituents, the study of the relationship between CIELAB colour changes and changes in chemical composition due to irradiation is of practical importance both in cultural heritage and in contemporary artefacts and objects. Concerning the surface protection of wood, starting from the results obtained by testing different commercial products, the attention has been focused on Linfoil®, a novel organic preservative/consolidant product that seems to attract a great interest in the field of conservation of wooden artefacts. Linfoil® was chosen and analysed in order to understand its composition and its time stability using reflectance spectrophotometry, FT-IR spectroscopy and analytical pyrolysis coupled to a gas chromatographic-mass spectrometric system. Colour monitoring allowed to find that wood surface colour undergoes an important variation due to photo-irradiation, occurring within the first 24 hours and mainly due to L* decrease and b* increase. Though Linfoil® treatment modifies wood colour, nevertheless it seems to protect wood surface by reducing the yellowish. FT-IR spectroscopy allowed to investigate the rate of photo-degradation of wood surface due to lignin oxidation. The most important result is that a correlation of the colour changes may be derived with the photo-degradation of lignin obtained by FT-IR analysis.

Differentiation of Leishmania species by FT-IR spectroscopy

NASA Astrophysics Data System (ADS)

Aguiar, Josafá C.; Mittmann, Josane; Ferreira, Isabelle; Ferreira-Strixino, Juliana; Raniero, Leandro

2015-05-01

Leishmaniasis is a parasitic infectious disease caused by protozoa that belong to the genus Leishmania. It is transmitted by the bite of an infected female Sand fly. The disease is endemic in 88 countries Desjeux (2001) [1] (16 developed countries and 72 developing countries) on four continents. In Brazil, epidemiological data show the disease is present in all Brazilian regions, with the highest incidences in the North and Northeast. There are several methods used to diagnose leishmaniasis, but these procedures have many limitations, are time consuming, have low sensitivity, and are expensive. In this context, Fourier Transform Infrared Spectroscopy (FT-IR) analysis has the potential to provide rapid results and may be adapted for a clinical test with high sensitivity and specificity. In this work, FT-IR was used as a tool to investigate the promastigotes of Leishmaniaamazonensis, Leishmaniachagasi, and Leishmaniamajor species. The spectra were analyzed by cluster analysis and deconvolution procedure base on spectra second derivatives. Results: cluster analysis found four specific regions that are able to identify the Leishmania species. The dendrogram representation clearly indicates the heterogeneity among Leishmania species. The band deconvolution done by the curve fitting in these regions quantitatively differentiated the polysaccharides, amide III, phospholipids, proteins, and nucleic acids. L. chagasi and L. major showed a greater biochemistry similarity and have three bands that were not registered in L. amazonensis. The L. amazonensis presented three specific bands that were not recorded in the other two species. It is evident that the FT-IR method is an indispensable tool to discriminate these parasites. The high sensitivity and specificity of this technique opens up the possibilities for further studies about characterization of other microorganisms.

Evaluation of Polymerization Efficacy in Composite Resins via FT-IR Spectroscopy and Vickers Microhardness Test.

PubMed

Jafarzadeh, Tahereh-Sadat; Erfan, Mohammad; Behroozibakhsh, Marjan; Fatemi, Mostafa; Masaeli, Reza; Rezaei, Yashar; Bagheri, Hossein; Erfan, Yasaman

2015-01-01

Background and aims. Polymerization efficacy affects the properties and performance of composite resin restorations.The purpose of this study was to evaluate the effectiveness of polymerization of two micro-hybrid, two nano-hybrid and one nano-filled ormocer-based composite resins, cured by two different light-curing systems, using Fourier transformation infrared (FT-IR) spectroscopy and Vickers microhardness testing at two different depths (top surface, 2 mm). Materials and methods. For FT-IR spectrometry, five cylindrical specimens (5mm in diameter × 2 mm in length) were prepared from each composite resin using Teflon molds and polymerized for 20 seconds. Then, 70-μm wafers were sectioned at the top surface and at2mm from the top surface. The degree of conversion for each sample was calculated using FT-IR spectroscopy. For Vickers micro-hardness testing, three cylindrical specimens were prepared from each composite resin and polymerized for 20 seconds. The Vickers microhardness test (Shimadzu, Type M, Japan) was performed at the top and bottom (depth=2 mm) surfaces of each specimen. Three-way ANOVA with independent variables and Tukey tests were performed at 95% significance level. Results. No significant differences were detected in degree of conversion and microhardness between LED and QTH light-curing units except for the ormocer-based specimen, CeramX, which exhibited significantly higher DC by LED. All the composite resins showed a significantly higher degree of conversion at the surface. Microhardness was not significantly affected by depth, except for Herculite XRV Ultra and CeramX, which showed higher values at the surface. Conclusion. Composite resins containing nano-particles generally exhibited more variations in degree of conversion and microhardness.

Analysis of tissue specific progenitor cell differentiation using FT-IR

NASA Astrophysics Data System (ADS)

Ishii, Katsunori; Kimura, Akinori; Kushibiki, Toshihiro; Awazu, Kunio

2007-07-01

Tissue specific progenitor cells and its differentiations have got a lot of attentions in regenerative medicine. The process of differentiations, the formation of tissues, has become better understood by the study using a lot of cell types progressively. These studies of cells and tissue dynamics at molecular levels are carried out through various approaches like histochemical methods, application of molecular biology and immunology. However, in case of using regenerative sources (cells, tissues and biomaterials etc.) clinically, they are measured and quality-controlled by non-contact and non-destructive methods from the view point of safety. Or the analysis with small quantities of materials could be possible if the quantities of materials are acceptable. A non-contact and non-destructive quality control method has been required. Recently, the use of Fourier Transform Infrared spectroscopy (FT-IR) has been used to monitor biochemical changes in cells, and has gained considerable importance. The changes in the cells and tissues, which are subtle and often not obvious in the histpathological studies, are shown to be well resolved using FT-IR. Moreover, although most techniques designed to detect one or a few changes, FT-IR is possible to identify the changes in the levels of various cellular biochemicals simultaneously under in vivo and in vitro conditions. The objective of this study is to establish the infrared spectroscopy of tissue specific progenitor cell differentiations as a quality control of cell sources for regenerative medicine. In the present study, as a basic study, we examine the adipose differentiation kinetics of preadipose cells (3T3-L1) and the osteoblast differentiation kinetics of mesenchymal stem cells (Kusa-A1) to analyze the infrared absorption spectra.

Evaluation of Polymerization Efficacy in Composite Resins via FT-IR Spectroscopy and Vickers Microhardness Test

PubMed Central

Jafarzadeh, Tahereh-Sadat; Erfan, Mohammad; Behroozibakhsh, Marjan; Fatemi, Mostafa; Masaeli, Reza; Rezaei, Yashar; Bagheri, Hossein; Erfan, Yasaman

2015-01-01

Background and aims. Polymerization efficacy affects the properties and performance of composite resin restorations.The purpose of this study was to evaluate the effectiveness of polymerization of two micro-hybrid, two nano-hybrid and one nano-filled ormocer-based composite resins, cured by two different light-curing systems, using Fourier transformation infrared (FT-IR) spectroscopy and Vickers microhardness testing at two different depths (top surface, 2 mm). Materials and methods. For FT-IR spectrometry, five cylindrical specimens (5mm in diameter × 2 mm in length) were prepared from each composite resin using Teflon molds and polymerized for 20 seconds. Then, 70-μm wafers were sectioned at the top surface and at2mm from the top surface. The degree of conversion for each sample was calculated using FT-IR spectroscopy. For Vickers micro-hardness testing, three cylindrical specimens were prepared from each composite resin and polymerized for 20 seconds. The Vickers microhardness test (Shimadzu, Type M, Japan) was performed at the top and bottom (depth=2 mm) surfaces of each specimen. Three-way ANOVA with independent variables and Tukey tests were performed at 95% significance level. Results. No significant differences were detected in degree of conversion and microhardness between LED and QTH light-curing units except for the ormocer-based specimen, CeramX, which exhibited significantly higher DC by LED. All the composite resins showed a significantly higher degree of conversion at the surface. Microhardness was not significantly affected by depth, except for Herculite XRV Ultra and CeramX, which showed higher values at the surface. Conclusion. Composite resins containing nano-particles generally exhibited more variations in degree of conversion and microhardness. PMID:26889359

Infrared Spectroscopy of Carbonaceous-chondrite Inclusions in the Kapoeta Meteorite: Discovery of Nanodiamonds with New Spectral Features and Astrophysical Implications

NASA Astrophysics Data System (ADS)

Abdu, Yassir A.; Hawthorne, Frank C.; Varela, Maria E.

2018-03-01

We report the finding of nanodiamonds, coexisting with amorphous carbon, in carbonaceous-chondrite (CC) material from the Kapoeta achondritic meteorite by Fourier-transform infrared (FTIR) spectroscopy and micro-Raman spectroscopy. In the C–H stretching region (3100–2600 cm‑1), the FTIR spectrum of the Kapoeta CC material (KBr pellet) shows bands attributable to aliphatic CH2 and CH3 groups, and is very similar to IR spectra of organic matter in carbonaceous chondrites and the diffuse interstellar medium. Nanodiamonds, as evidenced by micro-Raman spectroscopy, were found in a dark region (∼400 μm in size) in the KBr pellet. Micro-FTIR spectra collected from this region are dramatically different from the KBr-pellet spectrum, and their C–H stretching region is dominated by a strong and broad absorption band centered at ∼2886 cm‑1 (3.47 μm), very similar to that observed in IR absorption spectra of hydrocarbon dust in dense interstellar clouds. Micro-FTIR spectroscopy also indicates the presence of an aldehyde and a nitrile, and both of the molecules are ubiquitous in dense interstellar clouds. In addition, IR peaks in the 1500–800 cm‑1 region are also observed, which may be attributed to different levels of nitrogen aggregation in diamonds. This is the first evidence for the presence of the 3.47 μm interstellar IR band in meteorites. Our results further support the assignment of this band to tertiary CH groups on the surfaces of nanodiamonds. The presence of the above interstellar bands and the absence of shock features in the Kapoeta nanodiamonds, as indicated by Raman spectroscopy, suggest formation by a nebular-condensation process similar to chemical-vapor deposition.

Physiochemical/Rheological Control of Nonmetallic Materials.

DTIC Science & Technology

1982-08-01

CONCLUSIONS ... .. .. . .oo.. .. .. .. .. .. .. .... 23 APPENDIX A - Infrared Spectra of Nonmetallic Consumables .. ......... 24 77’. 1SN 7.. Tiii LIST OF...Spectrometer IR Infrared Spectroscopy GC Gas Chromatrography MS Mass Spectrometry * DSC Differenitial Scanning Calorimetry RT Room Temperature ET Elevated...Linear Heating Rate *FTIR Fourier Transform Infrared TGA Thermogravimetric Analysis Vi 1.0 INTRODUCTION AND SUOARY Over the past 10 years

Comparative investigation of Fourier Transform Infrared (FT-IR) spectroscopy and X-ray Diffraction (XRD) in the determination of cotton fiber crystallinity

USDA-ARS?s Scientific Manuscript database

Despite considerable efforts in developing the curve-fitting protocol to evaluate the crystallinity index (CI) from the X-ray diffraction (XRD) measurement, in its present state XRD procedure can only provide a qualitative or semi-quantitative assessment of the amounts of crystalline or amorphous po...

Synthesis and application of a novel environmental C26 diglycidyl ester plasticizer based on castor oil for poly(vinyl chloride)

USDA-ARS?s Scientific Manuscript database

In this work, for the first time, a castor oil derived diglycidyl ester plasticizer (C26-DGE) was prepared and incorporated into poly(vinyl chloride) (PVC). The chemical structure of the product was characterized by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (...

Structure and magnetic properties of SiO{sub 2}/PCL novel sol–gel organic–inorganic hybrid materials

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

Catauro, Michelina, E-mail: michelina.catauro@unina2.it; Bollino, Flavia; Cristina Mozzati, Maria

2013-07-15

Organic–inorganic nanocomposite materials have been synthesized via sol–gel. They consist of an inorganic SiO{sub 2} matrix, in which different percentages of poly(ε-caprolactone) (PCL) have been incorporated. The formation of H-bonds among the carbonyl groups of the polymer chains and Si–OH group of the inorganic matrix has been proved by means of Fourier transform infrared spectroscopy (FT-IR) analysis and has been confirmed by solid-state nuclear magnetic resonance (NMR). X-Ray diffraction (XRD) analysis highlighted the amorphous nature of the synthesized materials. Scanning electron microscope (SEM) micrograph and atomic force microscope (AFM) topography showed their homogeneous morphology and nanostructure nature. Considering the opportunitymore » to synthesize these hybrid materials under microgravity conditions by means of magnetic levitation, superconducting quantum interference device (SQUID) magnetometry has been used to quantify their magnetic susceptibility. This measure has shown that the SiO{sub 2}/PCL hybrid materials are diamagnetic and that their diamagnetic susceptibility is independent of temperature and increases with the PCL amount. - Graphical abstract: Characterization and magnetic properties of SiO{sub 2}/PCL organic–inorganic hybrid materials synthesized via sol–gel. FT-IR, Fourier transform infrared spectroscopy; solid-state NMR: solid-state nuclear magnetic resonance; SQUID: superconducting quantum interference device. - Highlights: • Sol–gel synthesis of SiO{sub 2}/PCL amorphous class I organic–inorganic hybrid materials. • FT-IR and NMR analyses show the hydrogen bonds formation between SiO{sub 2} and PCL. • AFM and SEM analyses confirm that the SiO{sub 2}/PCL are homogenous hybrid materials. • The SQUID measures show that the simples are diamagnetic. • Diamagnetic susceptibility of SiO{sub 2}/PCL materials increases with the PCL amount.« less

Automated Fast Screening Method for Cocaine Identification in Seized Drug Samples Using a Portable Fourier Transform Infrared (FT-IR) Instrument.

PubMed

Mainali, Dipak; Seelenbinder, John

2016-05-01

Quick and presumptive identification of seized drug samples without destroying evidence is necessary for law enforcement officials to control the trafficking and abuse of drugs. This work reports an automated screening method to detect the presence of cocaine in seized samples using portable Fourier transform infrared (FT-IR) spectrometers. The method is based on the identification of well-defined characteristic vibrational frequencies related to the functional group of the cocaine molecule and is fully automated through the use of an expert system. Traditionally, analysts look for key functional group bands in the infrared spectra and characterization of the molecules present is dependent on user interpretation. This implies the need for user expertise, especially in samples that likely are mixtures. As such, this approach is biased and also not suitable for non-experts. The method proposed in this work uses the well-established "center of gravity" peak picking mathematical algorithm and combines it with the conditional reporting feature in MicroLab software to provide an automated method that can be successfully employed by users with varied experience levels. The method reports the confidence level of cocaine present only when a certain number of cocaine related peaks are identified by the automated method. Unlike library search and chemometric methods that are dependent on the library database or the training set samples used to build the calibration model, the proposed method is relatively independent of adulterants and diluents present in the seized mixture. This automated method in combination with a portable FT-IR spectrometer provides law enforcement officials, criminal investigators, or forensic experts a quick field-based prescreening capability for the presence of cocaine in seized drug samples. © The Author(s) 2016.

Analysis of fingerprints features of infrared spectra of various processed products of Radix Aconiti kusnezoffii

NASA Astrophysics Data System (ADS)

Tu-ya; Yang, Ping; Sun, Su-qin; Zhou, Qun; Bao, Xiao-hua; Noda, Isao

2010-06-01

Fourier-transform infrared spectroscopy (FTIR) and two-dimensional correlation infrared spectroscopy (2D-IR)) are employed to analyze various processed products and ether extracts of Radix Aconiti kusnezoffii. There is a resemblance among the spectra of different processed products. The major difference lies in the absorption peak at 1641 cm -1 in the IR spectra, which reflects the transformation of raw aconite to the processed products. There are distinctive differences in the absorption peaks in the range of 1800-1500 cm -1 in the second derivative spectra, which has better resolution, of different processed products. 2D-IR spectra, which elevate the resolution further, can present even more differences among the products in the range of 1800-800 cm -1. Analysis of ether extracts of various processed products proves that there are alcohols, esters, carboxylic acids or ketones in all of them. However, their contents in different samples have obvious differences. With the advantages of high resolution, high-speed and convenience, IR can quickly and precisely distinguish various processed products of Radix A. kusnezoffii, and can be applied to predict the tendency of transformation of the complicated chemical mixture systems under heat perturbation.

[Infrared spectroscopic analysis of Guilin watermelon frost products].

PubMed

Huang, Dong-lan; Chen, Xiao-kang; Xu, Yong-qun; Sun, Su-qin; Zhou, Qun; Lu, Wen-guan

2012-08-01

The objective of the present study is to analyze different products of Guilin watermelon frost by Fourier transform infrared spectroscopy (FTIR), second derivative infrared spectroscopy and two-dimensional correlation spectroscopy (2D-IR) under thermal perturbation. The structural information of the samples indicates that samples from the same factory but of different brands had some dissimilarities in the IR spectra, and the type and content of accessories of them were different compared with conventional IR spectra of samples, peaks at 638 and 616 cm(-1) all arise from anhydrous sodium sulfate in watermelon frost spray and watermelon frost capsule; the characteristic absorption peaks of the sucrose, dextrin or other accessories can be seen clearly in the spectra of watermelon frost throat-clearing buccal tablets, watermelon frost throat tablets and watermelon frost lozenge. And the IR spectra of watermelon frost lozenge is very similar to the IR spectra of sucrose, so it can be easily proved that the content of sucrose in watermelon frost lozenge is high. In the 2D-IR correlation spectra, the samples presented the differences in the position, number and relative intensity of autopeaks and correlation peak clusters. Consequently, the macroscopical fingerprint characters of FTIR, second derivative infrared spectra and 2D-IR spectra can not only provide the information about main chemical constituents in medical materials, but also analyze and identify the type and content of accessories in Guilin watermelon frost. In conclusion, the multi-steps IR macro-fingerprint method is rapid, effective, visual and accurate for pharmaceutical research.

The spectroscopic (FT-IR, FT-Raman, UV) and first order hyperpolarizability, HOMO and LUMO analysis of 3-aminobenzophenone by density functional method

NASA Astrophysics Data System (ADS)

Karabacak, M.; Kurt, M.; Cinar, M.; Ayyappan, S.; Sudha, S.; Sundaraganesan, N.

In this work, experimental and theoretical study on the molecular structure and the vibrational spectra of 3-aminobenzophenone (3-ABP) is presented. The vibrational frequencies of the title compound were obtained theoretically by DFT/B3LYP calculations employing the standard 6-311++G(d,p) basis set for optimized geometry and were compared with Fourier transform infrared spectrum (FTIR) in the region of 400-4000 cm-1 and with Fourier Transform Raman spectrum in the region of 50-4000 cm-1. Complete vibrational assignments, analysis and correlation of the fundamental modes for the title compound were carried out. The vibrational harmonic frequencies were scaled using scale factor, yielding a good agreement between the experimentally recorded and the theoretically calculated values.

FTIR-PAS: a powerful tool for characterising the chemical composition and predicting the labile C fraction of various organic waste products.

PubMed

Bekiaris, Georgios; Bruun, Sander; Peltre, Clément; Houot, Sabine; Jensen, Lars S

2015-05-01

Fourier transform infrared (FT-IR) spectroscopy has been used for several years as a fast, low-cost, reliable technique for characterising a large variety of materials. However, the strong influence of sample particle size and the inability to measure the absorption of very dark and opaque samples have made FTIR unsuitable for many waste materials. FTIR-photoacoustic spectroscopy (FTIR-PAS) can eliminate some of the shortcomings of traditional FTIR caused by scattering effects and reflection issues, and recent advances in PAS technology have made commercial instruments available. In this study, FTIR-PAS was used to characterise a wide range of organic waste products and predict their labile carbon fraction, which is normally determined from time-consuming assays. FTIR-PAS was found to be capable of predicting the labile fraction of carbon as efficiently as near infrared spectroscopy (NIR) and furthermore of identifying the compounds that are correlated with the predicted parameter, thus facilitating a more mechanistic interpretation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Far-IR measurements at Cerro Toco, Chile: FIRST, REFIR, and AERI

NASA Astrophysics Data System (ADS)

Cageao, Richard P.; Alford, J. Ashley; Johnson, David G.; Kratz, David P.; Mlynczak, Martin G.

2010-09-01

In mid-2009, the Radiative Heating in the Underexplored Bands Campaign II (RHUBC-II) was conducted from Cerro Toco, Chile, a high, dry, remote mountain plateau, 23°S , 67.8°W at 5.4km, in the Atacama Desert of Northern Chile. From this site, dominant IR water vapor absorption bands and continuum, saturated when viewed from the surface at lower altitudes, or in less dry locales, were investigated in detail, elucidating infrared (IR) absorption and emission in the atmosphere. Three Fourier Transform InfraRed (FTIR) instruments were at the site, the Far-Infrared Spectroscopy of the Troposphere (FIRST), the Radiation Explorer in the Far Infrared (REFIR), and the Atmospheric Emitted Radiance Interferometer (AERI). In a side-by-side comparison, these measured atmospheric downwelling radiation, with overlapping spectral coverage from 5 to 100μm (2000 to 100cm-1), and instrument spectral resolutions from 0.5 to 0.643cm-1, unapodized. In addition to the FTIR and other ground-based IR and microwave instrumentation, pressure/temperature/relative humidity measuring sondes, for atmospheric profiles to 18km, were launched from the site several times a day. The derived water vapor profiles, determined at times matching the FTIR measurement times, were used to model atmospheric radiative transfer. Comparison of instrument data, all at the same spectral resolution, and model calculations, are presented along with a technique for determining adjustments to line-by-line calculation continuum models. This was a major objective of the campaign.

Discrete frequency infrared microspectroscopy and imaging with a tunable quantum cascade laser

PubMed Central

Kole, Matthew R.; Reddy, Rohith K.; Schulmerich, Matthew V.; Gelber, Matthew K.; Bhargava, Rohit

2012-01-01

Fourier-transform infrared imaging (FT-IR) is a well-established modality but requires the acquisition of a spectrum over a large bandwidth, even in cases where only a few spectral features may be of interest. Discrete frequency infrared (DF-IR) methods are now emerging in which a small number of measurements may provide all the analytical information needed. The DF-IR approach is enabled by the development of new sources integrating frequency selection, in particular of tunable, narrow-bandwidth sources with enough power at each wavelength to successfully make absorption measurements. Here, we describe a DF-IR imaging microscope that uses an external cavity quantum cascade laser (QCL) as a source. We present two configurations, one with an uncooled bolometer as a detector and another with a liquid nitrogen cooled Mercury Cadmium Telluride (MCT) detector and compare their performance to a commercial FT-IR imaging instrument. We examine the consequences of the coherent properties of the beam with respect to imaging and compare these observations to simulations. Additionally, we demonstrate that the use of a tunable laser source represents a distinct advantage over broadband sources when using a small aperture (narrower than the wavelength of light) to perform high-quality point mapping. The two advances highlight the potential application areas for these emerging sources in IR microscopy and imaging. PMID:23113653

Miniature high-performance infrared spectrometer for space applications

NASA Astrophysics Data System (ADS)

Kruzelecky, Roman V.; Haddad, Emile; Wong, Brian; Lafrance, Denis; Jamroz, Wes; Ghosh, Asoke K.; Zheng, Wanping; Phong, Linh

2004-06-01

Infrared spectroscopy probes the characteristic vibrational and rotational modes of chemical bonds in molecules to provide information about both the chemical composition and the bonding configuration of a sample. The significant advantage of the Infrared spectral technique is that it can be used with minimal consumables to simultaneously detect a large variety of chemical and biochemical species with high chemical specificity. To date, relatively large Fourier Transform (FT-IR) spectrometers employing variations of the Michelson interferometer have been successfully employed in space for various IR spectroscopy applications. However, FT-IR systems are mechanically complex, bulky (> 15 kg), and require considerable processing. This paper discusses the use of advanced integrated optics and smart optical coding techniques to significantly extend the performance of miniature IR spectrometers by several orders of magnitude in sensitivity. This can provide the next-generation of compact, high-performance IR spectrometers with monolithically integrated optical systems for robust optical alignment. The entire module can weigh under 3 kg to minimize the mass penalty for space applications. Miniaturized IR spectrometers are versatile and very convenient for small and micro satellite based missions. They can be dedicated to the monitoring of the CO2 in an Earth Observation mission, to Mars exobiology exploration, as well as to vital life support in manned space system; such as the cabin air quality and the quality of the recycled water supply.

Miniature high-performance infrared spectrometer for space applications

NASA Astrophysics Data System (ADS)

Kruzelecky, Roman V.; Haddad, Emile; Wong, Brian; Lafrance, Denis; Jamroz, Wes; Ghosh, Asoke K.; Zheng, Wanping; Phong, Linh

2017-11-01

Infrared spectroscopy probes the characteristic vibrational and rotational modes of chemical bonds in molecules to provide information about both the chemical composition and the bonding configuration of a sample. The significant advantage of the Infrared spectral technique is that it can be used with minimal consumables to simultaneously detect a large variety of chemical and biochemical species with high chemical specificity. To date, relatively large Fourier Transform (FT-IR) spectrometers employing variations of the Michelson interferometer have been successfully employed in space for various IR spectroscopy applications. However, FT-IR systems are mechanically complex, bulky (> 15 kg), and require considerable processing. This paper discusses the use of advanced integrated optics and smart optical coding techniques to significantly extend the performance of miniature IR spectrometers by several orders of magnitude in sensitivity. This can provide the next generation of compact, high-performance IR spectrometers with monolithically integrated optical systems for robust optical alignment. The entire module can weigh under 3 kg to minimize the mass penalty for space applications. Miniaturized IR spectrometers are versatile and very convenient for small and micro satellite based missions. They can be dedicated to the monitoring of the CO2 in an Earth Observation mission, to Mars exobiology exploration, as well as to vital life support in manned space system; such as the cabin air quality and the quality of the recycled water supply.

Insights into the selective binding and toxic mechanism of microcystin to catalase

NASA Astrophysics Data System (ADS)

Hu, Yuandong; Da, Liangjun

2014-03-01

Microcystin is a sort of cyclic nonribosomal peptides produced by cyanobacteria. It is cyanotoxin, which can be very toxic for plants and animals including humans. The present study evaluated the interaction of microcystin and catalase, under physiological conditions by means of fluorescence, three-dimensional (3D) fluorescence, circular dichroism (CD), Fourier Transform infrared (FT-IR) spectroscopy, and enzymatic reactionkinetic techniques. The fluorescence data showed that microcystin could bind to catalase to form a complex. The binding process was a spontaneous molecular interaction procedure, in which electrostatic interactions played a major role. Energy transfer and fluorescence studies proved the existence of a static binding process. Additionally, as shown by the three-dimensional fluorescence, CD and FT-IR results, microcystin could lead to conformational and microenvironmental changes of the protein, which may affect the physiological functions of catalase. The work provides important insights into the toxicity mechanism of microcystin in vivo.

A comparison of microscopic and spectroscopic identification methods for analysis of microplastics in environmental samples.

PubMed

Song, Young Kyoung; Hong, Sang Hee; Jang, Mi; Han, Gi Myung; Rani, Manviri; Lee, Jongmyoung; Shim, Won Joon

2015-04-15

The analysis of microplastics in various environmental samples requires the identification of microplastics from natural materials. The identification technique lacks a standardized protocol. Herein, stereomicroscope and Fourier transform infrared spectroscope (FT-IR) identification methods for microplastics (<1mm) were compared using the same samples from the sea surface microlayer (SML) and beach sand. Fragmented microplastics were significantly (p<0.05) underestimated and fiber was significantly overestimated using the stereomicroscope both in the SML and beach samples. The total abundance by FT-IR was higher than by microscope both in the SML and beach samples, but they were not significantly (p>0.05) different. Depending on the number of samples and the microplastic size range of interest, the appropriate identification method should be determined; selecting a suitable identification method for microplastics is crucial for evaluating microplastic pollution. Copyright © 2015 Elsevier Ltd. All rights reserved.

Study of the interaction of deoxynivalenol with human serum albumin by spectroscopic technique and molecular modelling.

PubMed

Li, Yuqin; Wang, Hao; Jia, Baoxiu; Liu, Caihong; Liu, Ke; Qi, Yongxiu; Hu, Zhide

2013-01-01

The mechanism of interaction between deoxynivalenol (DON) and human serum albumin (HSA) was studied using spectroscopic methods including fluorescence spectra, UV-VIS, Fourier transform infrared (FT-IR) and circular dichroism (CD). The quenching mechanism was investigated in terms of the association constants, number of binding sites and basic thermodynamic parameters. The distance between the HSA donor and the acceptor DON was 2.80 nm as derived from fluorescence resonance energy transfer. The secondary structure compositions of free HSA and its DON complexes were estimated by the FT-IR spectra. Alteration of the secondary protein structure in the presence of DON was confirmed by UV-VIS and CD spectroscopy. Molecular modelling revealed that a DON-protein complex was stabilised by hydrophobic forces and hydrogen bonding. It was potentially useful for elucidating the toxigenicity of DON when combined with biomolecular function effect, transmembrane transport, toxicological testing and the other experiments.

Physicochemical properties of chars at different treatment temperatures.

PubMed

Kim, Sung Su; Kang, Youn Suk; Lee, Hyun Dong; Kim, Jae Kwan; Hong, Sung Chang

2012-02-01

In this study, the physicochemical properties of the char of Indonesian SM coal following heat treatment at various temperatures were evaluated using X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and morphological and specific surface area analysis. Based on these analyses, heat treatment of coal was determined to be the most effective in increasing the coal rank. In the XPS analysis, the C-O and C-O-C groups and quaternary-N species were found to be of a lower grade coal when the pretreatment temperature decreased, meanwhile the C-C group and pyridinic species increased. In the FT-IR analysis, the collapse of the C-O and C-O-C group was observed due to the collapse of the ether group. In SEM and Brunauer-Emmett-Teller (BET) analysis, a decrease in the ether group was shown to be accompanied with the formation of micropores.

Tamoxifen-model membrane interactions: an FT-IR study

NASA Astrophysics Data System (ADS)

Boyar, Handan; Severcan, Feride

1997-06-01

The temperature- and concentration-induced effects of tamoxifen (TAM) on dipalmitoyl phosphatidylcholine (DPPC) model membranes were investigated by the Fourier transform-infrared (FT-IR) spectroscopic technique. An investigation of the C-H stretching region and the CO mode reveals that the inclusion of TAM changes the physical properties of the DPPC multibilayers by (i) shifting the main phase transition to lower temperatures; (ii) broadening the transition profile slightly; (iii) disordering the system in the gel and in the liquid crystalline phases; (iv) increasing the dynamics in the gel phase and decreasing the dynamics of the acyl chains in the liquid crystalline phase; (v) increasing the mobility of the terminal methyl group region of the bilayer in the gel phase and decreasing it in the liquid crystalline phase; (vi) increasing the frequency of the CO stretching mode both in the gel and in the liquid crystalline phases, i.e. non-bonding with carbonyl groups.

Non-intercalative, deoxyribose binding of boric acid to calf thymus DNA.

PubMed

Ozdemir, Ayse; Gursaclı, Refiye Tekiner; Tekinay, Turgay

2014-05-01

The present study characterizes the effects of the boric acid binding on calf thymus DNA (ct-DNA) by spectroscopic and calorimetric methods. UV-Vis absorbance spectroscopy, circular dichroism (CD) spectroscopy, transmission electron microscopy (TEM), isothermal titration calorimetry (ITC), and Fourier transform infrared (FT-IR) spectroscopy were employed to characterize binding properties. Changes in the secondary structure of ct-DNA were determined by CD spectroscopy. Sizes and morphologies of boric acid-DNA complexes were determined by transmission electron microscopy (TEM). The kinetics of boric acid binding to calf thymus DNA (ct-DNA) was investigated by isothermal titration calorimetry (ITC). ITC results revealed that boric acid exhibits a moderate affinity to ct-DNA with a binding constant (K a) of 9.54 × 10(4) M(-1). FT-IR results revealed that boric acid binds to the deoxyribose sugar of DNA without disrupting the B-conformation at tested concentrations.

Computer analysis of ATR-FTIR spectra of paint samples for forensic purposes

NASA Astrophysics Data System (ADS)

Szafarska, Małgorzata; Woźniakiewicz, Michał; Pilch, Mariusz; Zięba-Palus, Janina; Kościelniak, Paweł

2009-04-01

A method of subtraction and normalization of IR spectra (MSN-IR) was developed and successfully applied to extract mathematically the pure paint spectrum from the spectrum of paint coat on different bases, both acquired by the Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) technique. The method consists of several stages encompassing several normalization and subtraction processes. The similarity of the spectrum obtained with the reference spectrum was estimated by means of the normalized Manhattan distance. The utility and performance of the method proposed were tested by examination of five different paints sprayed on plastic (polyester) foil and on fabric materials (cotton). It was found that the numerical algorithm applied is able - in contrast to other mathematical approaches conventionally used for the same aim - to reconstruct a pure paint IR spectrum effectively without a loss of chemical information provided. The approach allows the physical separation of a paint from a base to be avoided, hence a time and work-load of analysis to be considerably reduced. The results obtained prove that the method can be considered as a useful tool which can be applied to forensic purposes.

Photoacoustic FTIR spectroscopic study of undisturbed human cortical bone

NASA Astrophysics Data System (ADS)

Gu, Chunju; Katti, Dinesh R.; Katti, Kalpana S.

2013-02-01

Chemical pretreatment has been the prevailing sample preparation procedure for infrared (IR) spectroscopic studies on bone. However, experiments have indicated that chemical pretreatment can potentially affect the interactions between the components. Typically the IR techniques have involved transmission experiments. Here we report experimental studies using photoacoustic Fourier transform infrared spectroscopy (PA-FTIR). As a nondestructive technique, PA-FTIR can detect absorbance spectrum from a sample at controllable sampling depth and with little or no sample preparation. Additionally, the coupling inert gas, helium, which is utilized in the PA-FTIR system, can inhibit bacteria growth of bone by displacing oxygen. Therefore, we used this technique to study the undisturbed human cortical bone. It is found that photoacoustic mode (linear-scan, LS-PA-FTIR) can obtain basically similar spectra of bone as compared to the traditional transmission mode, but it seems more sensitive to amide III and ν2 carbonate bands. The ν3 phosphate band is indicative of detailed mineral structure and symmetry of native bone. The PA-FTIR depth profiling experiments on human cortical bone also indicate the influence of water on OH band and the cutting effects on amide I and mineral bands. Our results indicate that phosphate ion geometry appears less symmetric in its undisturbed state as detected by the PA-FTIR as compared to higher symmetry observed using transmission techniques on disturbed samples. Moreover, the PA-FTIR spectra indicate a band at 1747 cm-1 possibly resulting from Cdbnd O stretching of lipids, cholesterol esters, and triglycerides from the arteries. Comparison of the spectra in transverse and longitudinal cross-sections demonstrates that, the surface area of the longitudinal section bone appears to have more organic matrix exposed and with higher mineral stoichiometry.

Diagnostics of cancer tissues by fiber optic evanescent wave Fourier transform IR (FEW-FTIR) spectroscopy

NASA Astrophysics Data System (ADS)

Afanasyeva, Natalia I.; Kolyakov, Sergei F.; Letokhov, Vladilen S.; Golovkina, Viktoriya N.

1997-08-01

Fiber optic evanescent wave Fourier transform infrared (FEW- FTIR) spectroscopy using fiberoptic sensors operated in the attenuated total reflection (ATR) regime in the middle infrared (IR) region of the spectrum (850 - 1850 cm-1) has recently found application in the diagnostics of tissues. The method is suitable for noninvasive and rapid (seconds) direct measurements of the spectra of normal and pathological tissues in vitro, ex vivo and in vivo. The aim of our studies is the express testing of various tumor tissues at the early stages of their development. The method is expected to be further developed for endoscopic and biopsy applications. We measured in vivo the skin normal and malignant tissues on surface (directly on patients) in various cases of basaloma, melanoma and nevus. The experiments were performed in operating room for measurements of skin in the depth (under/in the layers of epidermis), human breast, stomach, lung, kidney tissues. The breast and skin tissues at different stages of tumor or cancer were distinguished very clearly in spectra of amide, side cyclic and noncyclic hydrogen bonded fragments of aminoacid residuals, phosphate groups and sugars. Computer monitoring is being developed for diagnostics.

Effect of temperature on the magnetic properties of nano-sized M-type barium hexagonal ferrites

NASA Astrophysics Data System (ADS)

Tchouank Tekou Carol, T.; Sharma, Jyoti; Mohammed, J.; Kumar, Sachin; Srivastava, A. K.

2017-07-01

The application of M-type hexagonal ferrites in electronic devices is increasing with technological advancement. This is due to the possibility of improving the physical and magnetic properties to suit the desired application. Enhanced magnetic properties make hexagonal ferrites suitable for hyper frequency and radar absorbing application. In this paper, we investigated the effect of heat-treatment temperature on the structural and magnetic properties of M-type barium hexagonal ferrites with chemical composition Ba1-xAlxFe12-yMnyO19 (x=0.6 and y=0.3) synthesized by sol-gel auto-combustion method and sintered at 750°C, 850°C, 950°C and 1050°C. Characterisations of the prepared samples were done using Fourier transform-infrared (FT-IR), and vibrating sample magnetometer (VSM). The formation of M-type hexaferrite has been confirmed from XRD. The presence of two prominent peaks between 400 cm-1 and 600 cm-1 in the spectra of Fourier transform-infrared spectroscopy (FT-IR) also shows the formation of ferrite phase. Saturation magnetisation (MS), remnant magnetisation (Mr), coercivity (Hc) and squareness ratio (SR) were calculated from the M-H loop obtained from vibrating sample magnetometer (VSM).

Comparison of the thermal stability of the α, β and γ phases in poly(vinylidene fluoride) based on in situ thermal Fourier transform infrared spectroscopy

NASA Astrophysics Data System (ADS)

Biswas, Anirban; Henkel, Karsten; Schmeißer, Dieter; Mandal, Dipankar

2017-12-01

The electroactive β phase of poly(vinylidene fluoride) (PVDF) is induced due to the aging time of PVDF solutions. The feasibility of the combination of the three crystalline polymorphs (α, β and γ) is demonstrated where their relative proportion within the PVDF film can be tailored by the simple monitoring of the preparation conditions. To identify all these phases, Fourier transform infrared (FT-IR) spectroscopy is carried out and it is spotlighted that the vibrational bands at 510 and 841 cm-1 are not sufficient to state the formation of the β phase. The main aim of this work is devoted to develop a better understanding on the thermal stability of these several phases of PVDF, which has a longstanding ambiguity persisting in this area. It has been found that the in situ thermal FT-IR spectroscopy is one of the best alternatives to understand this important issue. It is ascertained that the β phase is the least thermally stable phase among α, β and γ phases, whereas the γ phase is the most thermally stable phase.

Development and application of Fourier-transform infrared chemical imaging of tumour in human tissue.

PubMed

Petter, C H; Heigl, N; Rainer, M; Bakry, R; Pallua, J; Bonn, G K; Huck, C W

2009-01-01

Fourier-transform infrared (FT-IR) based mapping and imaging is a fast emerging technology which is being increasingly applied to investigate tissues in the high-throughput mode. The high resolution close to the cellular level, the possibility to determine the bio-distribution of molecules of interest (proteins, peptides, lipids, carbohydrates) without any pre-treatment and the offer to yield molecular structure information have brought evidence that this technique allows to gain new insights in cancer pathology. Thus, several individual mainly protein and peptide cancer markers ("biomarkers") can be identified from FT-IR tissue images, enabling accurate discrimination between healthy and tumour areas. Optimal data acquisition (spatial resolution, spectral resolution, signal to noise ratio), classification, and validation are necessary to establish practical protocols that can be translated to the qualitative and quantitative clinical routine analysis. Thereby, the development of modern fast infrared imaging systems has strongly supported its acceptance in clinical histopathology. In this review, the necessity of analysis based on global cancer statistics, instrumental setups and developments, experimental state of the art are summarised and applications to investigate different kinds of cancer (e.g., prostate, breast, cervical, colon, oral cavity) are shown and discussed in detail.

Diagnosis of Breast Cancer Based on FT-IR Spectroscopy

NASA Astrophysics Data System (ADS)

Venkatachalam, P.; Rao, L. Lakshmana; Kumar, N. Krishna; Jose, Anupama; Nazeer, Shaiju S.

2008-11-01

Breast cancer is one of the most important malignant forms of cancer and a great threat to life for women. In the present study, the spectral characteristics of human breast tissues in normal and cancerous state have been investigated by Fourier transform infrared (FT-IR) absorption spectroscopy in the spectral region from 4000 to 400 cm-1. Several spectral differences were detected in the frequency regions N-H stretching, C-H vibrations, amide bands and 900-1300 cm-1. The ratio of intensities of the bands of A3300/A3015 & A1650/A1550, A2924/A2853, A1080/A1236, A1204/A1650, A1055/A1467 and A1045/A1467 provide conformational changes of protein, lipids, nucleic acids, collagen, carbohydrates and glycogen respectively in the human breast tissues. There are obvious differences in the spectral features between normal and cancerous tissues because of changes in molecular compositions and structures that accompany the transformation from a normal to a cancerous state. The differences suggest that the spectral information are useful for the diagnosis of breast cancer and may serve as a basis for conformational changes in tissue components during carcinogenesis.

Chemometric compositional analysis of phenolic compounds in fermenting samples and wines using different infrared spectroscopy techniques.

PubMed

Aleixandre-Tudo, Jose Luis; Nieuwoudt, Helene; Aleixandre, Jose Luis; du Toit, Wessel

2018-01-01

The wine industry requires reliable methods for the quantification of phenolic compounds during the winemaking process. Infrared spectroscopy appears as a suitable technique for process control and monitoring. The ability of Fourier transform near infrared (FT-NIR), attenuated total reflectance mid infrared (ATR-MIR) and Fourier transform infrared (FT-IR) spectroscopies to predict compositional phenolic levels during red wine fermentation and aging was investigated. Prediction models containing a large number of samples collected over two vintages from several industrial fermenting tanks as well as wine samples covering a varying number of vintages were validated. FT-NIR appeared as the most accurate technique to predict the phenolic content. Although slightly less accurate models were observed, ATR-MIR and FT-IR can also be used for the prediction of the majority of phenolic measurements. Additionally, the slope and intercept test indicated a systematic error for the three spectroscopies which seems to be slightly more pronounced for HPLC generated phenolics data than for the spectrophotometric parameters. However, the results also showed that the predictions made with the three instruments are statistically comparable. The robustness of the prediction models was also investigated and discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization of process-induced damage in Cu/low-k interconnect structure by microscopic infrared spectroscopy with polarized infrared light

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

Seki, Hirofumi, E-mail: Hirofumi-Seki@trc.toray.co.jp; Hashimoto, Hideki; Ozaki, Yukihiro

Microscopic Fourier-transform infrared (FT-IR) spectra are measured for a Cu/low-k interconnect structure using polarized IR light for different widths of low-k spaces and Cu lines, and for different heights of Cu lines, on Si substrates. Although the widths of the Cu line and the low-k space are 70 nm each, considerably smaller than the wavelength of the IR light, the FT-IR spectra of the low-k film were obtained for the Cu/low-k interconnect structure. A suitable method was established for measuring the process-induced damage in a low-k film that was not detected by the TEM-EELS (Transmission Electron Microscope-Electron Energy-Loss Spectroscopy) using microscopicmore » IR polarized light. Based on the IR results, it was presumed that the FT-IR spectra mainly reflect the structural changes in the sidewalls of the low-k films for Cu/low-k interconnect structures, and the mechanism of generating process-induced damage involves the generation of Si-OH groups in the low-k film when the Si-CH{sub 3} bonds break during the fabrication processes. The Si-OH groups attract moisture and the OH peak intensity increases. It was concluded that the increase in the OH groups in the low-k film is a sensitive indicator of low-k damage. We achieved the characterization of the process-induced damage that was not detected by the TEM-EELS and speculated that the proposed method is applicable to interconnects with line and space widths of 70 nm/70 nm and on shorter scales of leading edge devices. The location of process-induced damage and its mechanism for the Cu/low-k interconnect structure were revealed via the measurement method.« less

Fourier transform infrared spectroscopy combined with chemometrics for discrimination of Curcuma longa, Curcuma xanthorrhiza and Zingiber cassumunar

NASA Astrophysics Data System (ADS)

Rohaeti, Eti; Rafi, Mohamad; Syafitri, Utami Dyah; Heryanto, Rudi

2015-02-01

Turmeric (Curcuma longa), java turmeric (Curcuma xanthorrhiza) and cassumunar ginger (Zingiber cassumunar) are widely used in traditional Indonesian medicines (jamu). They have similar color for their rhizome and possess some similar uses, so it is possible to substitute one for the other. The identification and discrimination of these closely-related plants is a crucial task to ensure the quality of the raw materials. Therefore, an analytical method which is rapid, simple and accurate for discriminating these species using Fourier transform infrared spectroscopy (FTIR) combined with some chemometrics methods was developed. FTIR spectra were acquired in the mid-IR region (4000-400 cm-1). Standard normal variate, first and second order derivative spectra were compared for the spectral data. Principal component analysis (PCA) and canonical variate analysis (CVA) were used for the classification of the three species. Samples could be discriminated by visual analysis of the FTIR spectra by using their marker bands. Discrimination of the three species was also possible through the combination of the pre-processed FTIR spectra with PCA and CVA, in which CVA gave clearer discrimination. Subsequently, the developed method could be used for the identification and discrimination of the three closely-related plant species.

Noise-band factor analysis of cancer Fourier transform infrared evanescent-wave fiber optical (FTIR-FEW) spectra

NASA Astrophysics Data System (ADS)

Sukuta, Sydney; Bruch, Reinhard F.

2002-05-01

The goal of this study is to test the feasibility of using noise factor/eigenvector bands as general clinical analytical tools for diagnoses. We developed a new technique, Noise Band Factor Cluster Analysis (NBFCA), to diagnose benign tumors via their Fourier transform IR fiber optic evanescent wave spectral data for the first time. The middle IR region of human normal skin tissue and benign and melanoma tumors, were analyzed using this new diagnostic technique. Our results are not in full-agreement with pathological classifications hence there is a possibility that our approaches could complement or improve these traditional classification schemes. Moreover, the use of NBFCA make it much easier to delineate class boundaries hence this method provides results with much higher certainty.

Fourier transform infrared spectroscopy of 2'-deoxycytidine aggregates in CDCl3 solutions

NASA Astrophysics Data System (ADS)

Biemann, Lars; Häber, Thomas; Maydt, Daniela; Schaper, Klaus; Kleinermanns, Karl

2011-03-01

We investigated the self-aggregation of 2'-deoxy-3',5'-bis(tert-butyldimethylsilyl)-cytidine dC(TBDMS)2 in CDCl3 solutions by Fourier transform infrared (FT-IR) spectroscopy and report the formation of larger aggregates than dimers in this solvent for the first time. The hydrogen bonding patterns in these complexes, which occur with increasing concentration may serve as a model for DNA super-structures such as triplexes. From the IR spectra, wavelength dependent absolute extinction coefficients of the monomer, dimer as well as a contribution from larger clusters which are supposedly trimers are deduced on the basis of a simple deconvolution method. Our results are supported by RI-B3LYP/TZVP calculations within the conductorlike screening model framework, to account for solvent effects in the ab initio calculations.

High-definition Fourier transform infrared spectroscopic imaging of prostate tissue

NASA Astrophysics Data System (ADS)

Wrobel, Tomasz P.; Kwak, Jin Tae; Kadjacsy-Balla, Andre; Bhargava, Rohit

2016-03-01

Histopathology forms the gold standard for cancer diagnosis and therapy, and generally relies on manual examination of microscopic structural morphology within tissue. Fourier-Transform Infrared (FT-IR) imaging is an emerging vibrational spectroscopic imaging technique, especially in a High-Definition (HD) format, that provides the spatial specificity of microscopy at magnifications used in diagnostic surgical pathology. While it has been shown for standard imaging that IR absorption by tissue creates a strong signal where the spectrum at each pixel is a quantitative "fingerprint" of the molecular composition of the sample, here we show that this fingerprint also enables direct digital pathology without the need for stains or dyes for HD imaging. An assessment of the potential of HD imaging to improve diagnostic pathology accuracy is presented.

FT-IR and DFT study of lemon peel

NASA Astrophysics Data System (ADS)

Berezin, K. V.; Likhter, A. M.; Shagautdinova, I. T.; Chernavina, M. L.; Novoselova, A. V.

2017-03-01

Experimental FT-IR spectra of lemon peel are registered in the 650 - 3800 cm-1 range. The influence of peel artificial and natural dehydration on its vibrational spectrum is studied. The colored outer surface of lemon peel is proved not to have a significant impact on FT-IR spectrum. It is determined that only dehydration processes affect the FT-IR vibrational spectrum of the peel when a lemon is stored for 28 days under natural laboratory conditions. Polymer molecule models for dietary fibers, such as cellulose, hemicellulose, pectin, lignin, as well as hesperidin - flavonoid glycoside, and free moisture cluster are developed within the framework of DFT/B3LYP/6-31G(d) theoretical method. By implementing supramolecular approach, modeling of the vibrational FT-IR spectrum of lemon peel is carried out and its detailed theoretical interpretation is presented.

Principles, performance, and applications of spectral reconstitution (SR) in quantitative analysis of oils by Fourier transform infrared spectroscopy (FT-IR).

PubMed

García-González, Diego L; Sedman, Jacqueline; van de Voort, Frederik R

2013-04-01

Spectral reconstitution (SR) is a dilution technique developed to facilitate the rapid, automated, and quantitative analysis of viscous oil samples by Fourier transform infrared spectroscopy (FT-IR). This technique involves determining the dilution factor through measurement of an absorption band of a suitable spectral marker added to the diluent, and then spectrally removing the diluent from the sample and multiplying the resulting spectrum to compensate for the effect of dilution on the band intensities. The facsimile spectrum of the neat oil thus obtained can then be qualitatively or quantitatively analyzed for the parameter(s) of interest. The quantitative performance of the SR technique was examined with two transition-metal carbonyl complexes as spectral markers, chromium hexacarbonyl and methylcyclopentadienyl manganese tricarbonyl. The estimation of the volume fraction (VF) of the diluent in a model system, consisting of canola oil diluted to various extents with odorless mineral spirits, served as the basis for assessment of these markers. The relationship between the VF estimates and the true volume fraction (VF(t)) was found to be strongly dependent on the dilution ratio and also depended, to a lesser extent, on the spectral resolution. These dependences are attributable to the effect of changes in matrix polarity on the bandwidth of the ν(CO) marker bands. Excellent VF(t) estimates were obtained by making a polarity correction devised with a variance-spectrum-delineated correction equation. In the absence of such a correction, SR was shown to introduce only a minor and constant bias, provided that polarity differences among all the diluted samples analyzed were minimal. This bias can be built into the calibration of a quantitative FT-IR analytical method by subjecting appropriate calibration standards to the same SR procedure as the samples to be analyzed. The primary purpose of the SR technique is to simplify preparation of diluted samples such that only approximate proportions need to be adhered to, rather than using exact weights or volumes, the marker accounting for minor variations. Additional applications discussed include the use of the SR technique in extraction-based, quantitative, automated FT-IR methods for the determination of moisture, acid number, and base number in lubricating oils, as well as of moisture content in edible oils.

Predicting ambient aerosol thermal-optical reflectance (TOR) measurements from infrared spectra: organic carbon

NASA Astrophysics Data System (ADS)

Dillner, A. M.; Takahama, S.

2015-03-01

Organic carbon (OC) can constitute 50% or more of the mass of atmospheric particulate matter. Typically, organic carbon is measured from a quartz fiber filter that has been exposed to a volume of ambient air and analyzed using thermal methods such as thermal-optical reflectance (TOR). Here, methods are presented that show the feasibility of using Fourier transform infrared (FT-IR) absorbance spectra from polytetrafluoroethylene (PTFE or Teflon) filters to accurately predict TOR OC. This work marks an initial step in proposing a method that can reduce the operating costs of large air quality monitoring networks with an inexpensive, non-destructive analysis technique using routinely collected PTFE filter samples which, in addition to OC concentrations, can concurrently provide information regarding the composition of organic aerosol. This feasibility study suggests that the minimum detection limit and errors (or uncertainty) of FT-IR predictions are on par with TOR OC such that evaluation of long-term trends and epidemiological studies would not be significantly impacted. To develop and test the method, FT-IR absorbance spectra are obtained from 794 samples from seven Interagency Monitoring of PROtected Visual Environment (IMPROVE) sites collected during 2011. Partial least-squares regression is used to calibrate sample FT-IR absorbance spectra to TOR OC. The FTIR spectra are divided into calibration and test sets by sampling site and date. The calibration produces precise and accurate TOR OC predictions of the test set samples by FT-IR as indicated by high coefficient of variation (R2; 0.96), low bias (0.02 μg m-3, the nominal IMPROVE sample volume is 32.8 m3), low error (0.08 μg m-3) and low normalized error (11%). These performance metrics can be achieved with various degrees of spectral pretreatment (e.g., including or excluding substrate contributions to the absorbances) and are comparable in precision to collocated TOR measurements. FT-IR spectra are also divided into calibration and test sets by OC mass and by OM / OC ratio, which reflects the organic composition of the particulate matter and is obtained from organic functional group composition; these divisions also leads to precise and accurate OC predictions. Low OC concentrations have higher bias and normalized error due to TOR analytical errors and artifact-correction errors, not due to the range of OC mass of the samples in the calibration set. However, samples with low OC mass can be used to predict samples with high OC mass, indicating that the calibration is linear. Using samples in the calibration set that have different OM / OC or ammonium / OC distributions than the test set leads to only a modest increase in bias and normalized error in the predicted samples. We conclude that FT-IR analysis with partial least-squares regression is a robust method for accurately predicting TOR OC in IMPROVE network samples - providing complementary information to the organic functional group composition and organic aerosol mass estimated previously from the same set of sample spectra (Ruthenburg et al., 2014).

Sulfato/thiosulfato reducing bacteria characterization by FT-IR spectroscopy: a new approach to biocorrosion control.

PubMed

Rubio, Celine; Ott, Christelle; Amiel, Caroline; Dupont-Moral, Isabelle; Travert, Josette; Mariey, Laurence

2006-03-01

Sulfato and Thiosulfato Reducing Bacteria (SRB, TRB) can induce corrosion process on steel immersed in seawater. This phenomenon, called biocorrosion, costs approximatively 5 billion euros in France each year. We provide the first evidence that Fourier Transformed InfraRed (FTIR) spectroscopy is a competitive technique to evaluate the sulfurogen flora involved in biocorrosion in comparison with time consuming classical identification methods or PCR analyses. A great discrimination was obtained between SRB, TRB and some contamination bacteria known to be present in seawater and seem to be able to reduce sulfate under particular conditions. Moreover, this preliminary study demonstrates that FTIR spectroscopic and genotypic results present a good correlation (these results are confirmed by other data obtained before or later, data not shown here). The advantages gained by FTIR spectroscopy are to give information on strain phenotype and bacterial metabolism which are of great importance in corrosion processes.

Analysis and identification of two reconstituted tobacco sheets by three-level infrared spectroscopy

NASA Astrophysics Data System (ADS)

Wu, Xian-xue; Xu, Chang-hua; Li, Ming; Sun, Su-qin; Li, Jin-ming; Dong, Wei

2014-07-01

Two kinds of reconstituted tobacco (RT) from France (RTF) and China (RTC) were analyzed and identified by a three-level infrared spectroscopy method (Fourier-transform infrared spectroscopy (FT-IR) coupled with second derivative infrared spectroscopy (SD-IR) and two-dimensional infrared correlation spectroscopy (2D-IR)). The conventional IR spectra of RTF parallel samples were more consistent than those of RTC according to their overlapped parallel spectra and IR spectra correlation coefficients. FT-IR spectra of both two RTs were similar in holistic spectral profile except for small differences around 1430 cm-1, indicating that they have similar chemical constituents. By analysis of SD-IR spectra of RTFs and RTCs, more distinct fingerprint features, especially peaks at 1106 (1110), 1054 (1059) and 877 (874) cm-1, were disclosed. Even better reproducibility of five SD-IR spectra of RTF in 1750-1400 cm-1 could be seen intuitively from their stacked spectra and could be confirmed by further similarity evaluation of SD-IR spectra. Existence of calcium carbonate and calcium oxalate could be easily observed in two RTs by comparing their spectra with references. Furthermore, the 2D-IR spectra provided obvious, vivid and intuitive differences of RTF and RTC. Both two RTs had a pair of strong positive auto-peaks in 1600-1400 cm-1. Specifically, the autopeak at 1586 cm-1 in RTF was stronger than the one around 1421 cm-1, whereas the one at 1587 cm-1 in RTC was weaker than that at 1458 cm-1. Consequently, the RTs of two different brands were analyzed and identified thoroughly and RTF had better homogeneity than RTC. As a result, three-level infrared spectroscopy method has proved to be a simple, convenient and efficient method for rapid discrimination and homogeneousness estimation of RT.

Vasorelaxation Study and Tri-Step Infrared Spectroscopy Analysis of Malaysian Local Herbs

PubMed Central

Tan, Chu Shan; Loh, Yean Chun; Ahmad, Mariam; Zaini Asmawi, Mohd.; Yam, Mun Fei

2016-01-01

Objectives: The aim of this paper is to investigate the activities of Malaysian local herbs (Clinacanthus nutans Lindau, Strobilanthes crispus, Murdannia bracteata, Elephantopus scaber Linn., Pereskia bleo, Pereskia grandifolia Haw., Vernonia amygdalina, and Swietenia macrophylla King) for anti-hypertensive and vasorelaxant activity. An infrared (IR) macro-fingerprinting technique consisting of conventional fourier transform IR (FTIR), second-derivative IR (SD-IR), and two-dimensional correlation IR (2D-correlation IR) analyses were used to determine the main constituents and the fingerprints of the Malaysian local herbs. Methods: The herbs were collected, ground into powder form, and then macerated by using three different solvents: distilled water, 50% ethanol, and 95% ethanol, respectively. The potentials of the extracts produced from these herbs for use as vasorelaxants were determined. Additionally, the fingerprints of these herbs were analyzed by using FTIR spectra, SD-IR spectra, and 2D-correlation IR spectra in order to identify their main constituents and to provide useful information for future pharmacodynamics studies. Results: Swietenia macrophylla King has the highest potential in terms of vasorelaxant activity, followed by Vernonia amygdalina, Pereskia bleo, Strobilanthes crispus, Elephantopus scaber Linn., Pereskia grandifolia Haw., Clinacanthus nutans Lindau, and Murdannia bracteata. The tri-step IR macro-fingerprint of the herbs revealed that most of them contained proteins. Pereskia bleo and Pereskia grandifolia Haw. were found to contain calcium oxalate while Swietenia macrophylla King was found to contain large amounts of flavonoids. Conclusion: The flavonoid content of the herbs affects their vasorelaxant activity, and the tri-step IR macro- fingerprint method can be used as an analytical tool to determine the activity of a herbal medicine in terms of its vasorelaxant effect. PMID:27386148

Generation of chemical movies: FT-IR spectroscopic imaging of segmented flows.

PubMed

Chan, K L Andrew; Niu, X; deMello, A J; Kazarian, S G

2011-05-01

We have previously demonstrated that FT-IR spectroscopic imaging can be used as a powerful, label-free detection method for studying laminar flows. However, to date, the speed of image acquisition has been too slow for the efficient detection of moving droplets within segmented flow systems. In this paper, we demonstrate the extraction of fast FT-IR images with acquisition times of 50 ms. This approach allows efficient interrogation of segmented flow systems where aqueous droplets move at a speed of 2.5 mm/s. Consecutive FT-IR images separated by 120 ms intervals allow the generation of chemical movies at eight frames per second. The technique has been applied to the study of microfluidic systems containing moving droplets of water in oil and droplets of protein solution in oil. The presented work demonstrates the feasibility of the use of FT-IR imaging to study dynamic systems with subsecond temporal resolution.

Spectroscopic studies of gel grown zinc doped calcium hydrogen phosphate dihydrate crystals

NASA Astrophysics Data System (ADS)

Suryawanshi, V. B.; Chaudhari, R. T.

2018-05-01

The influence of zinc doping on the gel grown calcium hydrogen phosphate dihydrate crystals was studied using the spectroscopic techniques, which included SEM, FTIR and EDAX. It was found that, zinc ions transform the morphology of brushite crystals from rectangular plate shaped crystals to branching microcrystal patterns. However in FT-IR spectroscopy, as compared to undoped brushite crystals few vibrations were shifted to higher value. The observed changes in the vibrations were due to the impact of zinc ions. EDAX techniques is use to determine the percentage composition of elements present in the doped crystals. It revealed that the sample was of a mixed composition.

Surface morphology and improved electrical conductivity of camphorsulfonic acid surfactant based PANI nano composite

NASA Astrophysics Data System (ADS)

Niranjana, M.; Yesappa, L.; Ashokkumar, S. P.; Vijeth, H.; Devendrappa, H.

2018-05-01

Polyaniline and its composites at different wt. % of Copper oxide nano (PCC1 and PCC5) were prepared by in-situ chemical reaction method. The composites were characterized by Fourier Transform Infrared (FT-IR) Spectroscopy, Field Emission Scanning Electron Microscopy (FESEM) and the impedance measurement was carried out at different temperature. FTIR and SEM image reveals the presence of copper metal ions uniformly embedded into PANI. The dc electrical conductivity increases with increasing nano concentration in PANI and achieved high conductivity for PCC5. These results are suggesting PCC composite is a prominent candidate for supercapacitor properties and optoelectronics devices applications.

Use of attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy in direct, non-destructive, and rapid assessment of developmental cotton fibers grown in planta and in culture

USDA-ARS?s Scientific Manuscript database

Cotton fibers are routinely harvested from cotton plants (in planta), and their end-use qualities depend on their development stages. Cotton fibers are also cultured at controlled laboratory environments, so that cotton researchers can investigate many aspects of experimental protocols in cotton bre...

Monitoring Prepregs As They Cure

NASA Technical Reports Server (NTRS)

Young, P. R.; Gleason, J. R.; Chang, A. C.

1986-01-01

Quality IR spectra obtained in dynamic heating environment. New technique obtains quality infrared spectra on graphite-fiber-reinforced, polymeric-matrix-resin prepregs as they cure. Technique resulted from modification of diffuse reflectance/Fourier transform infrared (DR/FTIR) technique previously used to analyze environmentally exposed cured graphite composites. Technique contribute to better understanding of prepreg chemistry/temperature relationships and development of more efficient processing cycles for advanced materials.

Diagnostic segregation of human brain tumours using Fourier-transform infrared and/or Raman spectroscopy coupled with discriminant analysis†

PubMed Central

Gajjar, Ketan; Heppenstall, Lara D.; Pang, Weiyi; Ashton, Katherine M.; Trevisan, Júlio; Patel, Imran I.; Llabjani, Valon; Stringfellow, Helen F.; Martin-Hirsch, Pierre L.; Dawson, Timothy; Martin, Francis L.

2013-01-01

The most common initial treatment received by patients with a brain tumour is surgical removal of the growth. Precise histopathological diagnosis of brain tumours is to some extent subjective. Furthermore, currently available diagnostic imaging techniques to delineate the excision border during cytoreductive surgery lack the required spatial precision to aid surgeons. We set out to determine whether infrared (IR) and/or Raman spectroscopy combined with multivariate analysis could be applied to discriminate between normal brain tissue and different tumour types (meningioma, glioma and brain metastasis) based on the unique spectral “fingerprints” of their biochemical composition. Formalin-fixed paraffin-embedded tissue blocks of normal brain and different brain tumours were de-waxed, mounted on low-E slides and desiccated before being analyzed using attenuated total reflection Fourier-transform IR (ATR-FTIR) and Raman spectroscopy. ATR-FTIR spectroscopy showed a clear segregation between normal and different tumour subtypes. Discrimination of tumour classes was also apparent with Raman spectroscopy. Further analysis of spectral data revealed changes in brain biochemical structure associated with different tumours. Decreased tentatively-assigned lipid-to-protein ratio was associated with increased tumour progression. Alteration in cholesterol esters-to-phenylalanine ratio was evident in grade IV glioma and metastatic tumours. The current study indicates that IR and/or Raman spectroscopy have the potential to provide a novel diagnostic approach in the accurate diagnosis of brain tumours and have potential for application in intra-operative diagnosis. PMID:24098310

Implementation of Time-Resolved Step-Scan Fourier Transform Infrared (FT-IR) Spectroscopy Using a kHz Repetition Rate Pump Laser

PubMed Central

MAGANA, DONNY; PARUL, DZMITRY; DYER, R. BRIAN; SHREVE, ANDREW P.

2011-01-01

Time-resolved step-scan Fourier transform infrared (FT-IR) spectroscopy has been shown to be invaluable for studying excited-state structures and dynamics in both biological and inorganic systems. Despite the established utility of this method, technical challenges continue to limit the data quality and more wide ranging applications. A critical problem has been the low laser repetition rate and interferometer stepping rate (both are typically 10 Hz) used for data acquisition. Here we demonstrate significant improvement in the quality of time-resolved spectra through the use of a kHz repetition rate laser to achieve kHz excitation and data collection rates while stepping the spectrometer at 200 Hz. We have studied the metal-to-ligand charge transfer excited state of Ru(bipyridine)3Cl2 in deuterated acetonitrile to test and optimize high repetition rate data collection. Comparison of different interferometer stepping rates reveals an optimum rate of 200 Hz due to minimization of long-term baseline drift. With the improved collection efficiency and signal-to-noise ratio, better assignments of the MLCT excited-state bands can be made. Using optimized parameters, carbonmonoxy myoglobin in deuterated buffer is also studied by observing the infrared signatures of carbon monoxide photolysis upon excitation of the heme. We conclude from these studies that a substantial increase in performance of ss-FT-IR instrumentation is achieved by coupling commercial infrared benches with kHz repetition rate lasers. PMID:21513597

High definition infrared spectroscopic imaging for lymph node histopathology.

PubMed

Leslie, L Suzanne; Wrobel, Tomasz P; Mayerich, David; Bindra, Snehal; Emmadi, Rajyasree; Bhargava, Rohit

2015-01-01

Chemical imaging is a rapidly emerging field in which molecular information within samples can be used to predict biological function and recognize disease without the use of stains or manual identification. In Fourier transform infrared (FT-IR) spectroscopic imaging, molecular absorption contrast provides a large signal relative to noise. Due to the long mid-IR wavelengths and sub-optimal instrument design, however, pixel sizes have historically been much larger than cells. This limits both the accuracy of the technique in identifying small regions, as well as the ability to visualize single cells. Here we obtain data with micron-sized sampling using a tabletop FT-IR instrument, and demonstrate that the high-definition (HD) data lead to accurate identification of multiple cells in lymph nodes that was not previously possible. Highly accurate recognition of eight distinct classes - naïve and memory B cells, T cells, erythrocytes, connective tissue, fibrovascular network, smooth muscle, and light and dark zone activated B cells was achieved in healthy, reactive, and malignant lymph node biopsies using a random forest classifier. The results demonstrate that cells currently identifiable only through immunohistochemical stains and cumbersome manual recognition of optical microscopy images can now be distinguished to a similar level through a single IR spectroscopic image from a lymph node biopsy.

FT-IR spectroscopy: A powerful tool for studying the inter- and intraspecific biodiversity of cultivable non-Saccharomyces yeasts isolated from grape must.

PubMed

Grangeteau, Cédric; Gerhards, Daniel; Terrat, Sebastien; Dequiedt, Samuel; Alexandre, Hervé; Guilloux-Benatier, Michèle; von Wallbrunn, Christian; Rousseaux, Sandrine

2016-02-01

The efficiency of the FT-IR technique for studying the inter- and intra biodiversity of cultivable non-Saccharomyces yeasts (NS) present in different must samples was examined. In first, the capacity of the technique FT-IR to study the global diversity of a given sample was compared to the pyrosequencing method, used as a reference technique. Seven different genera (Aureobasidium, Candida, Cryptococcus, Hanseniaspora, Issatchenkia, Metschnikowia and Pichia) were identified by FT-IR and also by pyrosequencing. Thirty-eight other genera were identified by pyrosequencing, but together they represented less than 6% of the average total population of 6 musts. Among the species identified, some of them present organoleptic potentials in winemaking, particularly Starmerella bacillaris (synonym Candidazemplinina). So in a second time, we evaluated the capacity of the FT-IR technique to discriminate the isolates of this species because few techniques were able to study intraspecific NS yeast biodiversity. The results obtained were validated by using a classic method as ITS sequencing. Biodiversity at strain level was high: 19 different strains were identified from 58 isolates. So, FT-IR spectroscopy seems to be an accurate and reliable method for identifying major genera present in the musts. The two biggest advantages of the FT-IR are the capacity to characterize intraspecific biodiversity of non-Saccharomyces yeasts and the possibility to discriminate a lot of strains. Copyright © 2015 Elsevier B.V. All rights reserved.

Use of partial least squares regression for the multivariate calibration of hazardous air pollutants in open-path FT-IR spectrometry

NASA Astrophysics Data System (ADS)

Hart, Brian K.; Griffiths, Peter R.

1998-06-01

Partial least squares (PLS) regression has been evaluated as a robust calibration technique for over 100 hazardous air pollutants (HAPs) measured by open path Fourier transform infrared (OP/FT-IR) spectrometry. PLS has the advantage over the current recommended calibration method of classical least squares (CLS), in that it can look at the whole useable spectrum (700-1300 cm-1, 2000-2150 cm-1, and 2400-3000 cm-1), and detect several analytes simultaneously. Up to one hundred HAPs synthetically added to OP/FT-IR backgrounds have been simultaneously calibrated and detected using PLS. PLS also has the advantage in requiring less preprocessing of spectra than that which is required in CLS calibration schemes, allowing PLS to provide user independent real-time analysis of OP/FT-IR spectra.

Microbiology neutralization of zearalenone using Lactococcus lactis and Bifidobacterium sp.

PubMed

Król, A; Pomastowski, P; Rafińska, K; Railean-Plugaru, V; Walczak, J; Buszewski, B

2018-01-01

The aim of the study was to neutralize zearalenone by lactic acid bacteria (LAB) such as Lactococcus lactis and Bifidobacterium sp. and investigate the mechanism of zearalenone (ZEA) binding. Neutralization of ZEA by LAB was confirmed by identification of binding kinetics and spectroscopic studies such as Fourier transform infrared spectroscopy (FT-IR) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The obtained results showed that the kinetic process of zearalenone binding to L. lactis is not homogeneous but is expressed with an initial rapid stage with about 90% of ZEA biosorption and with a much slower second step. In case of Bifidobacterium sp., the neutralization process is homogeneous; the main stage can be described with about 88% of ZEA biosorption. MALDI-TOF-MS measurements and FTIR analysis confirmed the uptake of zearalenone molecules by bacterial species. Moreover, the assessment of dead and live lactic acid bacteria cells after zearalenone treatment was performed using fluorescence microscopy. Graphical abstract Microbiology neutralization of zearalenone using Lactococcus lactis and Bifidobacterium sp. was confirmed by identification of binding kinetics and spectroscopic studies such as FT-IR spectroscopy and MALDI-TOF-MS spectrometry. The mechanism of ZEA binding was also investigated.

Binding of the bioactive component Aloe dihydroisocoumarin with human serum albumin

NASA Astrophysics Data System (ADS)

Zhang, Xiu-Feng; Xie, Ling; Liu, Yang; Xiang, Jun-Feng; Tang, Ya-Lin

2008-11-01

Aloe dihydroisocoumarin, one of new components isolated from Aloe vera, can scavenge reactive oxygen species. In order to explore the mechanism of drug action at a molecular level, the binding of Aloe dihydroisocoumarin with human serum albumin (HSA) has been investigated by using fluorescence, ultraviolet (UV), circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy, fluorescence dynamics, and molecular dynamic docking for the first time. We observed a quenching of fluorescence of HSA in the presence of Aloe dihydroisocoumarin and also analyzed the quenching results using the Stern-Volmer equation and obtained high affinity binding to HSA. An isoemissive point at 414 nm is seen, indicating that the quenching of HSA fluorescence depends on the formation of Aloe dihydroisocoumarin-HSA complex, which is further confirmed by fluorescence dynamic result. From the CD and FT-IR results, it is apparent that the interaction of Aloe dihydroisocoumarin with HSA causes a conformational change of the protein, with the gain of α-helix, β-sheet and random coil stability and the loss of β-turn content. Data obtained by fluorescence spectroscopy, fluorescence dynamics, CD, and FTIR experiments along with the docking studies suggest that Aloe dihydroisocoumarin binds to residues located in subdomain IIA of HSA.

Application of mid-infrared spectroscopy in analyzing different segmented production of Angelica by AB-8 macroporous resin

NASA Astrophysics Data System (ADS)

Guo, Yizhen; Wang, Jingjuan; Lu, Lina; Sun, Suqin; Liu, Yang; Xiao, Yao; Qin, Youwen; Xiao, Lijuan; Wen, Haoran; Qu, Lei

2016-01-01

As complicated mixture systems, chemical components of Angelica are very difficult to identify and discriminate, so as not to control its quality effectively. In recent years, Mid-infrared spectroscopy has been innovatively employed to identify and assess the quality of Traditional Chinese medicine (TCM) products. In this paper, the macroscopic IR fingerprint method including Fourier transform infrared spectroscopy (FT-IR), the second derivative infrared spectroscopy (SD-IR) and two-dimensional correlation infrared spectroscopy (2D-IR), are applied to study and identify Angelica raw material, the decoction and different segmented production of AB-8 macroporous resin. FT-IR spectrum indicates that Angelica raw material is rich in sucrose and the correlation coefficient is 0.8465. The decoction of Angelica contains varieties of polysaccharides components and the content is gradually decreased with increasing concentration of ethanol. In addition, the decoction of Angelica contains a certain amount of protein components and 50% ethanol eluate has more protein than other eluates. Their second derivative spectra amplify the differences and reveal the potentially characteristic IR absorption bands, then we conclude that the decoction of Angelica contains a certain amount of ferulic acid and ligustilide. And 30% ethanol eluate, 50% ethanol eluate and 70% ethanol eluate are similar to ligustilide. Further, 2D-IR spectra enhance the spectral resolution and obtain much new information for discriminating the similar complicated samples. It is demonstrated that the above three-step infrared spectroscopy could be applicable for effective, visual and accurate analysis and identification of very complicated and similar mixture systems of traditional Chinese medicines.

3D FT-IR imaging spectroscopy of phase-separation in a poly(3-hydroxybutyrate)/poly(L-lactic acid) blend

Treesearch

Miriam Unger; Julia Sedlmair; Heinz W. Siesler; Carol Hirschmugl; Barbara Illman

2014-01-01

In the present study, 3D FT-IR spectroscopic imaging measurements were applied to study the phase separation of a poly(3-hydroxybutyrate) (PHB)/poly(L-lactic acid) (PLA) (50:50 wt.%) polymer blend film. While in 2D projection imaging the z-dependent information is overlapped, thereby complicating the analysis, FT-IR spectro-micro-tomography,...

Collaborative Student Laboratory Exercise Using FT-IR Spectroscopy for the Kinetics Study of a Biotin Analogue

ERIC Educational Resources Information Center

Leong, Jhaque; Ackroyd, Nathan C.; Ho, Karen

2014-01-01

The synthesis of N-methoxycarbonyl-2-imidazolidone, an analogue of biotin, was conducted by organic chemistry students and confirmed using FT-IR and H NMR. Spectroscopy students used FT-IR to measure the rate of hydrolysis of the product and determined the rate constant for the reaction using the integrated rate law. From the magnitude of the rate…

Direct-on-Filter α-Quartz Estimation in Respirable Coal Mine Dust Using Transmission Fourier Transform Infrared Spectrometry and Partial Least Squares Regression

PubMed Central

Miller, Arthur L.; Weakley, Andrew Todd; Griffiths, Peter R.; Cauda, Emanuele G.; Bayman, Sean

2017-01-01

In order to help reduce silicosis in miners, the National Institute for Occupational Health and Safety (NIOSH) is developing field-portable methods for measuring airborne respirable crystalline silica (RCS), specifically the polymorph α-quartz, in mine dusts. In this study we demonstrate the feasibility of end-of-shift measurement of α-quartz using a direct-on-filter (DoF) method to analyze coal mine dust samples deposited onto polyvinyl chloride filters. The DoF method is potentially amenable for on-site analyses, but deviates from the current regulatory determination of RCS for coal mines by eliminating two sample preparation steps: ashing the sampling filter and redepositing the ash prior to quantification by Fourier transform infrared (FT-IR) spectrometry. In this study, the FT-IR spectra of 66 coal dust samples from active mines were used, and the RCS was quantified by using: (1) an ordinary least squares (OLS) calibration approach that utilizes standard silica material as done in the Mine Safety and Health Administration's P7 method; and (2) a partial least squares (PLS) regression approach. Both were capable of accounting for kaolinite, which can confound the IR analysis of silica. The OLS method utilized analytical standards for silica calibration and kaolin correction, resulting in a good linear correlation with P7 results and minimal bias but with the accuracy limited by the presence of kaolinite. The PLS approach also produced predictions well-correlated to the P7 method, as well as better accuracy in RCS prediction, and no bias due to variable kaolinite mass. Besides decreased sensitivity to mineral or substrate confounders, PLS has the advantage that the analyst is not required to correct for the presence of kaolinite or background interferences related to the substrate, making the method potentially viable for automated RCS prediction in the field. This study demonstrated the efficacy of FT-IR transmission spectrometry for silica determination in coal mine dusts, using both OLS and PLS analyses, when kaolinite was present. PMID:27645724

Direct-on-Filter α-Quartz Estimation in Respirable Coal Mine Dust Using Transmission Fourier Transform Infrared Spectrometry and Partial Least Squares Regression.

PubMed

Miller, Arthur L; Weakley, Andrew Todd; Griffiths, Peter R; Cauda, Emanuele G; Bayman, Sean

2017-05-01

In order to help reduce silicosis in miners, the National Institute for Occupational Health and Safety (NIOSH) is developing field-portable methods for measuring airborne respirable crystalline silica (RCS), specifically the polymorph α-quartz, in mine dusts. In this study we demonstrate the feasibility of end-of-shift measurement of α-quartz using a direct-on-filter (DoF) method to analyze coal mine dust samples deposited onto polyvinyl chloride filters. The DoF method is potentially amenable for on-site analyses, but deviates from the current regulatory determination of RCS for coal mines by eliminating two sample preparation steps: ashing the sampling filter and redepositing the ash prior to quantification by Fourier transform infrared (FT-IR) spectrometry. In this study, the FT-IR spectra of 66 coal dust samples from active mines were used, and the RCS was quantified by using: (1) an ordinary least squares (OLS) calibration approach that utilizes standard silica material as done in the Mine Safety and Health Administration's P7 method; and (2) a partial least squares (PLS) regression approach. Both were capable of accounting for kaolinite, which can confound the IR analysis of silica. The OLS method utilized analytical standards for silica calibration and kaolin correction, resulting in a good linear correlation with P7 results and minimal bias but with the accuracy limited by the presence of kaolinite. The PLS approach also produced predictions well-correlated to the P7 method, as well as better accuracy in RCS prediction, and no bias due to variable kaolinite mass. Besides decreased sensitivity to mineral or substrate confounders, PLS has the advantage that the analyst is not required to correct for the presence of kaolinite or background interferences related to the substrate, making the method potentially viable for automated RCS prediction in the field. This study demonstrated the efficacy of FT-IR transmission spectrometry for silica determination in coal mine dusts, using both OLS and PLS analyses, when kaolinite was present.

Structural and magnetic properties of nanocrystalline NiFe2O4 thin film prepared by spray pyrolysis technique

NASA Astrophysics Data System (ADS)

Chavan, Apparao R.; Chilwar, R. R.; Shisode, M. V.; Hivrekar, Mahesh M.; Mande, V. K.; Jadhav, K. M.

2018-05-01

The nanocrystalline NiFe2O4 thin film has been prepared using a spray pyrolysis technique on glass substrate. The prepared thin film was characterized by using X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FTIR), and Field Emission-Scanning Electron Microscopy (FE-SEM) characterization techniques for the structural and microstructural analysis. The magnetic property was measured using vibrating sample magnetometer (VSM) at room temperature. X-ray diffraction studies show the formation of single phase spinel structure of the thin film. The octahedral and tetrahedral vibration in the sample was studied by Fourier transform infrared (FT-IR) spectra. Magnetic hysteresis loop was recorded for thin film at room temperature. At 15 kOe, saturation magnetization (Ms) was found to increase while coercivity (Hc) decreases with thickness of the NiFe2O4 thin film.

[Spectral characteristics of decomposition of incorporated straw in compound polluted arid loess].

PubMed

Fan, Chun-Hui; Zhang, Ying-Chao; Xu, Ji-Ting; Wang, Jia-Hong

2014-04-01

The original loess from western China was used as soil sample, the spectral methods of scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDS), elemental analysis, Fourier transform infrared spectroscopy (FT-IR) and 13C nuclear magnetic resonance (13C NMR) were used to investigate the characteristics of decomposed straw and formed humic acids in compound polluted arid loess. The SEM micrographs show the variation from dense to decomposed surface, and finally to damaged structure, and the EDS data reveal the phenomenon of element transfer. The newly-formed humic acids are of low aromaticity, helpful for increasing the activity of organic matters in loess. The FTIR spectra in the whole process are similar, indicating the complexity of transformation dynamics of humic acids. The molecular structure of humic acids becomes simpler, shown from 13C NMR spectra. The spectral methods are useful for humic acids identification in loess region in straw incorporation process.

Step-Scan T-Cell Fourier Transform Infrared Photoacoustic Spectroscopy (FTIR-PAS) for Monitoring Environmental Air Pollutants

NASA Astrophysics Data System (ADS)

Liu, Lixian; Mandelis, Andreas; Melnikov, Alexander; Michaelian, Kirk; Huan, Huiting; Haisch, Christoph

2016-07-01

Air pollutants have adverse effects on the Earth's climate system. There is an urgent need for cost-effective devices capable of recognizing and detecting various ambient pollutants. An FTIR photoacoustic spectroscopy (FTIR-PAS) method based on a commercial FTIR spectrometer developed for air contamination monitoring will be presented. A resonant T-cell was determined to be the most appropriate resonator in view of the low-frequency requirement and space limitations in the sample compartment. Step-scan FTIR-PAS theory for regular cylinder resonator has been described as a reference for prediction of T-cell vibration principles. Both simulated amplitude and phase responses of the T-cell show good agreement with measurement data Carbon dioxide IR absorption spectra were used to demonstrate the capacity of the FTIR-PAS method to detect ambient pollutants. The theoretical detection limit for carbon dioxide was found to be 4 ppmv. A linear response to carbon dioxide concentration was found in the range from 2500 ppmv to 5000 ppmv. The results indicate that it is possible to use step-scan FTIR-PAS with a T-cell as a quantitative method for analysis of ambient contaminants.

FT-IR imaging for quantitative determination of liver fat content in non-alcoholic fatty liver.

PubMed

Kochan, K; Maslak, E; Chlopicki, S; Baranska, M

2015-08-07

In this work we apply FT-IR imaging of large areas of liver tissue cross-section samples (∼5 cm × 5 cm) for quantitative assessment of steatosis in murine model of Non-Alcoholic Fatty Liver (NAFLD). We quantified the area of liver tissue occupied by lipid droplets (LDs) by FT-IR imaging and Oil Red O (ORO) staining for comparison. Two alternative FT-IR based approaches are presented. The first, straightforward method, was based on average spectra from tissues and provided values of the fat content by using a PLS regression model and the reference method. The second one – the chemometric-based method – enabled us to determine the values of the fat content, independently of the reference method by means of k-means cluster (KMC) analysis. In summary, FT-IR images of large size liver sections may prove to be useful for quantifying liver steatosis without the need of tissue staining.

Real time observation of proteolysis with Fourier transform infrared (FT-IR) and UV-circular dichroism spectroscopy: Watching a protease eat a protein

NASA Astrophysics Data System (ADS)

Güler, Günnur; Džafić, Enela; Vorob'ev, Mikhail M.; Vogel, Vitali; Mäntele, Werner

2011-06-01

Fourier transform infrared (FT-IR)- and UV-circular dichroism (UV-CD) spectroscopy have been used to study real-time proteolytic digestion of β-lactoglobulin (β-LG) and β-casein (β-CN) by trypsin at various substrate/enzyme ratios in D 2O-buffer at 37 °C. Both techniques confirm that protein substrate looses its secondary structure upon conversion to the peptide fragments. This perturbation alters the backbone of the protein chain resulting in conformational changes and degrading of the intact protein. Precisely, the most significant spectral changes which arise from digestion take place in the amide I and amide II regions. The FT-IR spectra for the degraded β-LG show a decrease around 1634 cm -1, suggesting a decrease of β-sheet structure in the course of hydrolysis. Similarly, the intensity around the 1654 cm -1 band decreases for β-CN digested by trypsin, indicating a reduction in the α-helical part. On the other hand, the intensity around ˜1594 cm -1 and ˜1406 cm -1 increases upon enzymatic breakdown of both substrates, suggesting an increase in the antisymmetric and symmetric stretching modes of free carboxylates, respectively, as released digestion products. Observation of further H/D exchange in the course of digestion manifests the structural opening of the buried groups and accessibility to the core of the substrate. On the basis of the UV-CD spectra recorded for β-LG and β-CN digested by trypsin, the unordered structure increases concomitant with a decrease in the remaining structure, thus, revealing breakdown of the intact protein into smaller fragments. This model study in a closed reaction system may serve as a basis for the much more complex digestion processes in an open reaction system such as the stomach.

Differentiation of different mixed Listeria strains and also acid-injured, heat-injured, and repaired cells of Listeria monocytogenes using fourier transform infrared spectroscopy.

PubMed

Nyarko, Esmond; Donnelly, Catherine

2015-03-01

Fourier transform infrared (FT-IR) spectroscopy was used to differentiate mixed strains of Listeria monocytogenes and mixed strains of L. monocytogenes and Listeria innocua. FT-IR spectroscopy was also applied to investigate the hypothesis that heat-injured and acid-injured cells would return to their original physiological integrity following repair. Thin smears of cells on infrared slides were prepared from cultures for mixed strains of L. monocytogenes, mixed strains of L. monocytogenes and L. innocua, and each individual strain. Heat-injured and acid-injured cells were prepared by exposing harvested cells of L. monocytogenes strain R2-764 to a temperature of 56 ± 0.2°C for 10 min or lactic acid at pH 3 for 60 min, respectively. Cellular repair involved incubating aliquots of acid-injured and heat-injured cells separately in Trypticase soy broth supplemented with 0.6% yeast extract for 22 to 24 h; bacterial thin smears on infrared slides were prepared for each treatment. Spectral collection was done using 250 scans at a resolution of 4 cm(-1) in the mid-infrared wavelength region. Application of multivariate discriminant analysis to the wavelength region from 1,800 to 900 cm(-1) separated the individual L. monocytogenes strains. Mixed strains of L. monocytogenes and L. monocytogenes cocultured with L. innocua were successfully differentiated from the individual strains when the discriminant analysis was applied. Different mixed strains of L. monocytogenes were also successfully separated when the discriminant analysis was applied. A data set for injury and repair analysis resulted in the separation of acid-injured, heat-injured, and intact cells; repaired cells clustered closer to intact cells when the discriminant analysis (1,800 to 600 cm(-1)) was applied. FT-IR spectroscopy can be used for the rapid source tracking of L. monocytogenes strains because it can differentiate between different mixed strains and individual strains of the pathogen.

Characterization of developmental immature fiber (im) mutant and Texas Marker-1 (TM-1) cotton fibers by Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) spectroscopy

USDA-ARS?s Scientific Manuscript database

The immature fiber (im) mutant is one type of cotton fiber mutants with unique characteristics of non-fluffy cotton bolls. Compared to its near-isogenic wild type Texas Marker-1 (TM-1), im fiber has thin secondary cell wall and is less mature. In this work, we applied the previously proposed princip...

Environmentally Benign Repair of Composites Using High Temperature Cyanate Ester Nanocomposites

DTIC Science & Technology

2010-10-01

temperature by magnetic stirring. Thermogravimetric analysis (TG) measurements were performed on a TG model Q50 (TA Instruments, Inc.) to determine the...standard 1259-85. These experiments were also compared with thermogravimetric analysis (TGA) in both dynamic heating and isothermal conditions. The...characterized with thermogravimetric analysis (TG) and Fourier transform infrared spectroscopy (FT-IR). For the TG, about 20 mg of sample was placed in

Mild and modular surface modification of cellulose via hetero Diels-Alder (HDA) cycloaddition.

PubMed

Goldmann, Anja S; Tischer, Thomas; Barner, Leonie; Bruns, Michael; Barner-Kowollik, Christopher

2011-04-11

A combination of reversible addition-fragmentation chain transfer (RAFT) polymerization and hetero Diels-Alder (HDA) cycloaddition was used to effect, under mild (T ≈ 20 °C), fast, and modular conditions, the grafting of poly(isobornyl acrylate) (M(n) = 9800 g mol(-1), PDI = 1.19) onto a solid cellulose substrate. The active hydroxyl groups expressed on the cellulose fibers were converted to tosylate leaving groups, which were subsequently substituted by a highly reactive cyclopentadienyl functionality (Cp). By employing the reactive Cp-functionality as a diene, thiocarbonyl thio-capped poly(isobornyl acrylate) synthesized via RAFT polymerization (mediated by benzyl pyridine-2-yldithioformiate (BPDF)) was attached to the surface under ambient conditions by an HDA cycloaddition (reaction time: 15 h). The surface-modified cellulose samples were analyzed in-depth by X-ray photoelectron spectroscopy, scanning electron microscopy, elemental analysis, Fourier transform infrared (FT-IR) spectroscopy as well as Fourier transform infrared microscopy employing a focal plane array detector for imaging purposes. The analytical results provide strong evidence that the reaction of suitable dienophiles with Cp-functional cellulose proceeds under mild reaction conditions (T ≈ 20 °C) in an efficient fashion. In particular, the visualization of individual modified cellulose fibers via high-resolution FT-IR microscopy corroborates the homogeneous distribution of the polymer film on the cellulose fibers.

Thermal and spectroscopic analysis of organic matter degradation and humification during composting of pig slurry in different scenarios.

PubMed

Martín-Mata, J; Lahoz-Ramos, C; Bustamante, M A; Marhuenda-Egea, F C; Moral, R; Santos, A; Sáez, J A; Bernal, M P

2016-09-01

In this work, different analytical techniques (thermal analysis, (13)C cross-polarization magic angle spinning (CPMAS) NMR and Fourier transform infrared (FT-IR) spectroscopy) have been used to study the organic matter changes during the co-composting of pig slurry with cotton gin waste. To ensure the validity of the findings, the composting process was developed in different scenarios: under experimental pilot plant conditions, using the static pile system, and under real conditions on a pig farm, using the turning pile system. Also, the thermal stability index (R1) was determined before and after an extraction with water, to evaluate the effect of eliminating water-soluble inorganic salts on the thermal analysis. The results of the thermal methods showed the degradation of the most labile organic matter during composting; R1 increased during composting in all piles, without any influence of the presence of water-soluble inorganic ions in the sample. The NMR showed a decrease in the abundance of the carbohydrate molecules and an increase in the aliphatic materials during composting, due to a concentration effect. Also, FT-IR spectroscopy was a useful technique to study the trends of polysaccharides and nitrate, as indicators of organic matter transformations during composting.

Analysis of Trans Fat in Edible Oils with Cooking Process

PubMed Central

Song, Juhee; Park, Joohyeok; Jung, Jinyeong; Lee, Chankyu; Gim, Seo Yeoung; Ka, HyeJung; Yi, BoRa; Kim, Mi-Ja; Kim, Cho-il

2015-01-01

Trans fat is a unsaturated fatty acid with trans configuration and separated double bonds. Analytical methods have been introduced to analyze trans fat content in foods including infrared (IR) spectroscopy, gas chromatography (GC), Fourier transform-infrared (FT-IR) spectroscopy, reverses-phase silver ion high performance liquid chromatography, and silver nitrate thin layer chromatography. Currently, FT-IR spectroscopy and GC are mostly used methods. Trans fat content in 6 vegetable oils were analyzed and processing effects including baking, stir-frying, pan-frying, and frying on the formation of trans fat in corn oil was evaluated by GC. Among tested vegetable oils, corn oil has 0.25 g trans fat/100 g, whereas other oils including rapeseed, soybean, olive, perilla, and sesame oils did not have detectable amount of trans fat content. Among cooking methods, stir-frying increased trans fat in corn oil whereas baking, pan-frying, and frying procedures did not make changes in trans fat content compared to untreated corn oils. However, the trans fat content was so low and food label can be declared as ‘0’ trans based on the regulation of Ministry of Food ad Drug Safety (MFDS) (< 2 g/100 g edible oil). PMID:26483890

Structural characterization and chemical classification of some bryophytes found in Latvia.

PubMed

Maksimova, Viktorija; Klavina, Laura; Bikovens, Oskars; Zicmanis, Andris; Purmalis, Oskars

2013-07-01

Bryophytes are the second largest taxonomic group in the plant kingdom; yet, studies conducted to better understand their chemical composition are rare. The aim of this study was to characterize the chemical composition of bryophytes common in Northern Europe by using elemental, spectral, and non-destructive analytical methods, such as Fourier transform IR spectrometry (FT-IR), solid-phase (13) C-NMR spectrometry, and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), for the purpose of investigating their chemotaxonomic relationships on the basis of chemical-composition data. The results of all these analyses showed that bryophytes consist mainly of carbohydrates. Judging by FT-IR spectra, the OH groups in combination of CO groups were the most abundant groups. The (13) C-NMR spectra provided information on the presence of such compounds as phenolics and lipids. It was found that the amount of phenolic compounds in bryophytes is relatively small. This finding definitely confirmed the absence of lignin in the studied bryophytes. Cluster analysis was used to better understand differences in the chemical composition of bryophyte samples and to evaluate possible usage of these methods in the chemotaxonomy of bryophytes. Copyright © 2013 Verlag Helvetica Chimica Acta AG, Zürich.

Flame retardancy and thermal behavior of intumescent flame-retardant EVA composites with an efficient triazine-based charring agent

NASA Astrophysics Data System (ADS)

Xu, Bo; Ma, Wen; Wu, Xiao; Qian, Lijun; Jiang, Shan

2018-04-01

Intumescent flame retardant (IFR) EVA composites were prepared based on a hyperbranched triazine charring-foaming agent (HTCFA) and ammonium polyphosphate (APP). The synergistic effect of HTCFA and APP on the flame retardancy and thermal behavior of the composites were investigated through flammability tests, cone calorimeter measurements, thermogravimetric analysis (TGA) including evolved gas analysis (TG-IR) and residue analysis (Fourier transform infrared (FTIR), laser Raman spectroscopy (LRS), x-ray Photoelectron Spectroscopy (XPS) and scanning electron microscopy (SEM)). The flammability test results showed HTCFA/APP (1/3) system presented the best synergistic effect in flame-retardant EVA composites with the highest LOI value and UL-94 V-0 rating. As for cone calorimeter results, IFR changed the combustion behavior of EVA and resulted in remarkable decrease of flammability and smoke product. TGA results showed the synergistic effect between APP and HTCFA could strengthen the char-forming ability of composites. TG-IR results indicated the melt viscosities and gas release with increasing temperature were well-correlated for EVA/IFR composite. The residue analysis results from SEM, LRS, FT-IR and XPS revealed IFR promoted forming more compact graphitic char layer, connected by rich P–O–C and P–N structures.

Analysis of Complex Carbohydrate Composition in Plant Cell Wall Using Fourier Transformed Mid-Infrared Spectroscopy (FT-IR).

PubMed

Badhan, Ajay; Wang, Yuxi; McAllister, Tim A

2017-01-01

Fourier transformed mid-infrared spectroscopy (FTIR) is a powerful tool for compositional analysis of plant cell walls (Acebes et al., Front Plant Sci 5:303, 2014; Badhan et al., Biotechnol Biofuels 7:1-15, 2014; Badhan et al., BioMed Res Int 2015: 562952, 2015; Roach et al., Plant Physiol 156:1351-1363, 2011). The infrared spectrum generates a fingerprint of a sample with absorption peaks corresponding to the frequency of vibrations between the bonds of the atoms making up the material. Here, we describe a method focused on the use of FTIR in combination with principal component analysis (PCA) to characterize the composition of the plant cell wall. This method has been successfully used to study complex enzyme saccharification processes like rumen digestion to identify recalcitrant moieties in low-quality forage which resist rumen digestion (Badhan et al., BioMed Res Int 2015: 562952, 2015), as well as to characterize cell wall mutant lines or transgenic lines expressing exogenous hydrolases (Badhan et al., Biotechnol Biofuels 7:1-15, 2014; Roach et al., Plant Physiol 156:1351-1363, 2011). The FTIR method described here facilitates high-throughput identification of the major compositional differences across a large set of samples in a low cost and nondestructive manner.

Fourier transform infrared spectroscopy combined with chemometrics for discrimination of Curcuma longa, Curcuma xanthorrhiza and Zingiber cassumunar.

PubMed

Rohaeti, Eti; Rafi, Mohamad; Syafitri, Utami Dyah; Heryanto, Rudi

2015-02-25

Turmeric (Curcuma longa), java turmeric (Curcuma xanthorrhiza) and cassumunar ginger (Zingiber cassumunar) are widely used in traditional Indonesian medicines (jamu). They have similar color for their rhizome and possess some similar uses, so it is possible to substitute one for the other. The identification and discrimination of these closely-related plants is a crucial task to ensure the quality of the raw materials. Therefore, an analytical method which is rapid, simple and accurate for discriminating these species using Fourier transform infrared spectroscopy (FTIR) combined with some chemometrics methods was developed. FTIR spectra were acquired in the mid-IR region (4000-400 cm(-1)). Standard normal variate, first and second order derivative spectra were compared for the spectral data. Principal component analysis (PCA) and canonical variate analysis (CVA) were used for the classification of the three species. Samples could be discriminated by visual analysis of the FTIR spectra by using their marker bands. Discrimination of the three species was also possible through the combination of the pre-processed FTIR spectra with PCA and CVA, in which CVA gave clearer discrimination. Subsequently, the developed method could be used for the identification and discrimination of the three closely-related plant species. Copyright © 2014 Elsevier B.V. All rights reserved.

Mechanistic and conformational studies on the interaction of food dye amaranth with human serum albumin by multispectroscopic methods.

PubMed

Zhang, Guowen; Ma, Yadi

2013-01-15

The mechanism of interaction between food dye amaranth and human serum albumin (HSA) in physiological buffer (pH 7.4) was investigated by fluorescence, UV-vis absorption, circular dichroism (CD), and Fourier transform infrared (FT-IR) spectroscopy. Results obtained from analysis of fluorescence spectra indicated that amaranth had a strong ability to quench the intrinsic fluorescence of HSA through a static quenching procedure. The negative value of enthalpy change and positive value of entropy change elucidated that the binding of amaranth to HSA was driven mainly by hydrophobic and hydrogen bonding interactions. The surface hydrophobicity of HSA increased after binding with amaranth. The binding distance between HSA and amaranth was estimated to be 3.03 nm and subdomain IIA (Sudlow site I) was the primary binding site for amaranth on HSA. The results of CD and FT-IR spectra showed that binding of amaranth to HSA induced conformational changes of HSA. Copyright © 2012 Elsevier Ltd. All rights reserved.

An efficient and environment-friendly method of removing graphene oxide in wastewater and its degradation mechanisms.

PubMed

Zhang, Chao-Zhi; Li, Ting; Yuan, Yang; Xu, Jianqiang

2016-06-01

Graphene and graphene oxide (GO) have already existed in air, water and soil due to their popular application in functional materials. However, degradation of graphene and GO in wastewater has not been reported. Degradation of GO plays a key role in the elimination of graphene and GO in wastewater due to graphene being easily oxidized to GO. In this paper, GO was completely degraded to give CO2 by Photo-Fenton. The degradation intermediates were determined by UV-vis absorption spectra, elemental analysis (EA), fourier transform infrared (FT-IR) and liquid chromatography-mass spectrometry (LC-MS). Experimental results showed that graphene oxide was completely degraded to give CO2 after 28 days. Based on UV, FT-IR, LC-MS spectra and EA data of these degradation intermediates, the degradation mechanisms of GO were supposed. This paper suggests an efficient and environment-friendly method to degrade GO and graphene. Copyright © 2016 Elsevier Ltd. All rights reserved.

Antibiofilm activity of coconut (Cocos nucifera Linn.) husk fibre extract.

PubMed

Viju, N; Satheesh, S; Vincent, S G P

2013-01-01

In this study, antibiofilm activity of coconut husk extract (CHE) was tested by various assays in the laboratory. The effects of CHE on extracellular polymeric substance (EPS) production, hydrophobicity and adhesion ability of Pseudomonas sp., Alteromonas sp. and Gallionella sp. and the antimicrobial activity of the extract against these bacteria were assessed. CHE was found to possess antibacterial activity against all the bacterial strains and affected the EPS production. The CHE affected the growth of the biofilm-forming bacteria in a culture medium. The hydrophobicity of the bacterial cells was also changed due to the CHE treatment. The active compound of the CHE was characterised by thin-layer chromatography (TLC), high performance liquid chromatography (HPLC) and fourier transform infrared (FT-IR) analysis. HPLC spectrum showed a single peak and the FT-IR spectrum indicated the presence of an OH-group-containing compound in the extract. In conclusion the CHE could be used as a source for the isolation of antifouling compounds.

Time-resolved spectral characterization of ring cavity surface emitting and ridge-type distributed feedback quantum cascade lasers by step-scan FT-IR spectroscopy.

PubMed

Brandstetter, Markus; Genner, Andreas; Schwarzer, Clemens; Mujagic, Elvis; Strasser, Gottfried; Lendl, Bernhard

2014-02-10

We present the time-resolved comparison of pulsed 2nd order ring cavity surface emitting (RCSE) quantum cascade lasers (QCLs) and pulsed 1st order ridge-type distributed feedback (DFB) QCLs using a step-scan Fourier transform infrared (FT-IR) spectrometer. Laser devices were part of QCL arrays and fabricated from the same laser material. Required grating periods were adjusted to account for the grating order. The step-scan technique provided a spectral resolution of 0.1 cm(-1) and a time resolution of 2 ns. As a result, it was possible to gain information about the tuning behavior and potential mode-hops of the investigated lasers. Different cavity-lengths were compared, including 0.9 mm and 3.2 mm long ridge-type and 0.97 mm (circumference) ring-type cavities. RCSE QCLs were found to have improved emission properties in terms of line-stability, tuning rate and maximum emission time compared to ridge-type lasers.

Univariate and multivariate analysis of tannin-impregnated wood species using vibrational spectroscopy.

PubMed

Schnabel, Thomas; Musso, Maurizio; Tondi, Gianluca

2014-01-01

Vibrational spectroscopy is one of the most powerful tools in polymer science. Three main techniques--Fourier transform infrared spectroscopy (FT-IR), FT-Raman spectroscopy, and FT near-infrared (NIR) spectroscopy--can also be applied to wood science. Here, these three techniques were used to investigate the chemical modification occurring in wood after impregnation with tannin-hexamine preservatives. These spectroscopic techniques have the capacity to detect the externally added tannin. FT-IR has very strong sensitivity to the aromatic peak at around 1610 cm(-1) in the tannin-treated samples, whereas FT-Raman reflects the peak at around 1600 cm(-1) for the externally added tannin. This high efficacy in distinguishing chemical features was demonstrated in univariate analysis and confirmed via cluster analysis. Conversely, the results of the NIR measurements show noticeable sensitivity for small differences. For this technique, multivariate analysis is required and with this chemometric tool, it is also possible to predict the concentration of tannin on the surface.

Structural characterization of Papilio kotzebuea (Eschscholtz 1821) butterfly wings

NASA Astrophysics Data System (ADS)

Sackey, J.; Nuru, Z. Y.; Berthier, S.; Maaza, M.

2018-05-01

The `plain black' forewings and black with `red spot' hindwings of the Papilio kotzebuea (Eschscholtz, 1821) were characterized by Scanning Electron Microscopy (SEM), Energy-Dispersive x-ray Spectroscopy (EDS), Atomic Force Microscopy (AFM), Fourier transform Infrared spectroscopy (FT-IR), UV-Vis spectrophometer and NIRQuest spectrometer. SEM images showed that the two sections of wings have different structures. The black with `red spot' hindwings have `hair-like' structures attached to the ridges and connected to the lamellae. On the contrary, the `plain black' forewings have holes that separate the ridges. AFM analysis unveiled that the `plain black' forewings have higher average surfaces roughness values as compared with the black with `red spot' hindwing. EDS and FT-IR results confirmed the presence of naturally hydrophobic materials on the wings. The `plain black' forewing exhibited strong absorptance (97%) throughout the solar spectrum range, which is attributed to the high melanin concentration as well as to the presence of holes in the scales. Biomimicking this wing could serves as equivalent solar absorber material.

Accounting for tissue heterogeneity in infrared spectroscopic imaging for accurate diagnosis of thyroid carcinoma subtypes.

PubMed

Martinez-Marin, David; Sreedhar, Hari; Varma, Vishal K; Eloy, Catarina; Sobrinho-Simões, Manuel; Kajdacsy-Balla, André; Walsh, Michael J

2017-07-01

Fourier transform infrared (FT-IR) microscopy was used to image tissue samples from twenty patients diagnosed with thyroid carcinoma. The spectral data were then used to differentiate between follicular thyroid carcinoma and follicular variant of papillary thyroid carcinoma using principle component analysis coupled with linear discriminant analysis and a Naïve Bayesian classifier operating on a set of computed spectral metrics. Classification of patients' disease type was accomplished by using average spectra from a wide region containing follicular cells, colloid, and fibrosis; however, classification of disease state at the pixel level was only possible when the extracted spectra were limited to follicular epithelial cells in the samples, excluding the relatively uninformative areas of fibrosis. The results demonstrate the potential of FT-IR microscopy as a tool to assist in the difficult diagnosis of these subtypes of thyroid cancer, and also highlights the importance of selectively and separately analyzing spectral information from different features of a tissue of interest.

Fabrication of hydroxyapatite from fish bones waste using reflux method

NASA Astrophysics Data System (ADS)

Cahyanto, A.; Kosasih, E.; Aripin, D.; Hasratiningsih, Z.

2017-02-01

The aim of this present study was to investigate the fabrication of hydroxyapatites, which were synthesized from fish bone wastes using reflux method. The fish bone wastes collected from the restaurant were brushed and boiled at 100°C for 10 minutes to remove debris and fat. After drying, the fish bones were crushed, and ball milled into a fine powder. The fish bone wastes were then processed by refluxing using KOH and H3PO4 solutions. The samples were calcined at 900°C and characterized by X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectrometry (FT-IR). The XRD pattern of samples after treatment revealed that the peak of hydroxyapatite was observed and the bands of OH- and PO4 3- were observed by FT-IR. The scanning electron microscope evaluation of sample showed the entangled crystal and porous structure of hydroxyapatite. In conclusion, the hydroxyapatite was successfully synthesized from fish bone wastes using reflux method.

Application of chemometrics in quality control of Turmeric (Curcuma longa) based on Ultra-violet, Fourier transform-infrared and 1H NMR spectroscopy.

PubMed

Gad, Haidy A; Bouzabata, Amel

2017-12-15

Turmeric (Curcuma longa L.) belongs to the family Zingiberaceae that is widely used as a spice in food preparations in addition to its biological activities. UV, FT-IR, 1 H NMR in addition to HPLC were applied to construct a metabolic fingerprint for Turmeric in an attempt to assess its quality. 30 samples were analyzed, and then principal component analysis (PCA) and hierarchical clustering analysis (HCA) were utilized to assess the differences and similarities between collected samples. PCA score plot based on both HPLC and UV spectroscopy showed the same discriminatory pattern, where the samples were segregated into four main groups depending on their total curcuminoids content. The results revealed that UV could be utilized as a simple and rapid alternative for HPLC. However, FT-IR failed to discriminate between the same species. By applying 1 H NMR, the metabolic variability between samples was more evident in the essential oils/fatty acid region. Copyright © 2017 Elsevier Ltd. All rights reserved.

Synthesis and characterization of CdO nano particles by the sol-gel method

NASA Astrophysics Data System (ADS)

Vadgama, V. S.; Vyas, R. P.; Jogiya, B. V.; Joshi, M. J.

2017-05-01

Cadmium Oxide (CdO) is an inorganic compound and one of the main precursors to other cadmium compounds. It finds applications in cadmium plating, storage batteries, in transparent conducting film, etc. Here, an attempt is made to synthesize CdO nano particles by sol-gel technique. The gel was prepared using cadmium nitrate tetra hydrate (Cd(NO3)2.4H2O) and aqueous ammonium hydroxide (NH4OH) as a precursor. The synthesized powder is further characterized by techniques like Powder X-ray diffraction (XRD), Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and Thermal gravimetric analysis (TGA). Powder XRD analysis suggested the nano-crystalline nature of the sample with the cubic crystal system. Nano scaled particles of spherical morphology with the size ranging from 50-100 nm are observed from TEM images. While, FT-IR study is used to confirm the presence of different functional groups. Thermo-gravimetric analysis suggests the highly thermally stable nature of the samples. The results are discussed.

Antibiofilm activity of coconut (Cocos nucifera Linn.) husk fibre extract

PubMed Central

Viju, N.; Satheesh, S.; Vincent, S.G.P.

2012-01-01

In this study, antibiofilm activity of coconut husk extract (CHE) was tested by various assays in the laboratory. The effects of CHE on extracellular polymeric substance (EPS) production, hydrophobicity and adhesion ability of Pseudomonas sp., Alteromonas sp. and Gallionella sp. and the antimicrobial activity of the extract against these bacteria were assessed. CHE was found to possess antibacterial activity against all the bacterial strains and affected the EPS production. The CHE affected the growth of the biofilm-forming bacteria in a culture medium. The hydrophobicity of the bacterial cells was also changed due to the CHE treatment. The active compound of the CHE was characterised by thin-layer chromatography (TLC), high performance liquid chromatography (HPLC) and fourier transform infrared (FT-IR) analysis. HPLC spectrum showed a single peak and the FT-IR spectrum indicated the presence of an OH-group-containing compound in the extract. In conclusion the CHE could be used as a source for the isolation of antifouling compounds. PMID:23961225

Modulating drug loading and release profile of beta-cyclodextrin polymers by means of cross-linked degree.

PubMed

Wang, Qi-fang; Li, San-ming; Zhang, Yu-yang; Zhang, Hong

2011-02-01

The purpose of the present study is to use beta-cyclodextrin polymers (beta-CDP) with different cross-linked degree (CLD) to form inclusion complexes with ibuprofen and examine the effects of structural and compositional factors of beta-CDP on its drug loading and release behaviors. A series of beta-CDP with different CLD were synthesized and characterized by Fourier Transform Infrared Spectroscopy (FT-IR) and 13C NMR spectrum. The beta-CDP was systemically characterized for the relation between the CLD of beta-CDP and the drug loading and release as well. The results of FT-IR and 13C NMR showed that similar peak-shaped vibration of beta-CDP and beta-CD implies that the polymer keeps the original characteristic structure of beta-CD. The CLD of the beta-CDP played a critical role in the drug loading and release, increasing the CLD resulted in reduction of drug loading, but increase in drug release.

Ligand-tailored single-site silica supported titanium catalysts: Synthesis, characterization and towards cyanosilylation reaction

NASA Astrophysics Data System (ADS)

Xu, Wei; Li, Yani; Yu, Bo; Yang, Jindou; Zhang, Ying; Chen, Xi; Zhang, Guofang; Gao, Ziwei

2015-01-01

A successive anchoring of Ti(NMe2)4, cyclopentadiene and a O-donor ligand, 1-hydroxyethylbenzene (PEA), 1,1‧-bi-2-naphthol (Binol) or 2,3-dihydroxybutanedioic acid diethyl ester (Tartrate), on silica was conducted by SOMC strategy in moderate conditions. The silica, monitored by in-situ Fourier transform infrared spectroscopy (in-situ FT-IR), was pretreated at different temperatures (200, 500 and 800 °C). The ligand tailored silica-supported titanium complexes were characterized by in-situ FT-IR, 13C CP MAS-NMR, X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge structure (XANES) and elemental analysis in detail, verifying that the surface titanium species are single sited. The catalytic activity of the ligand tailored single-site silica supported titanium complexes was evaluated by a cyanosilylation of benzaldehyde. The results showed that the catalytic activity is dependent strongly on the dehydroxylation temperatures of silica and the configuration of the ligands.

Eco-friendly and green synthesis of BiVO4 nanoparticle using microwave irradiation as photocatalayst for the degradation of Alizarin Red S

NASA Astrophysics Data System (ADS)

Abraham, S. Daniel; David, S. Theodore; Bennie, R. Biju; Joel, C.; Kumar, D. Sanjay

2016-06-01

Bismuth vanadate (BiVO4) nanocrystals have been successfully synthesised using microwave-assisted combustion synthesis (MCS), and characterised using Fourier transform infrared (FT-IR) and Raman spectra, surface area analysis (BET), X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy Dispersive X-ray analysis (EDX), diffused reflectance spectroscopy (DRS) and Photoluminescence (PL) spectroscopy. The XRD results confirmed the formation of monoclinic bismuth vanadate. The formations of BiO & VO43-vibrations were ascertained from FT-IR data. The morphology of hallow internal structural micro entities were confirmed by SEM. The optical properties were determined by DRS and PL spectra. Hence, the influence of the preparation methods on the structure, morphology and optical activities of bismuth vanadate was investigated systematically. Photocatalytic degradation (PCD) of Alizarin Red S (ARS), an effective disrupting chemical in aqueous medium was investigated using BiVO4 nanoparticles. The kinetics of PCD was found to follow pseudo first-order.

Nanocomposites based on pH-sensitive hydrogels and chitosan decorated carbon nanotubes with antibacterial properties.

PubMed

Bellingeri, Romina; Mulko, Lucinda; Molina, Maria; Picco, Natalia; Alustiza, Fabrisio; Grosso, Carolina; Vivas, Adriana; Acevedo, Diego F; Barbero, Cesar A

2018-09-01

The present work aimed to study the properties of a novel nanocomposite with promising biomedical applications. Nanocomposites were prepared by the addition of different concentrations of chitosan decorated carbon nanotubes to acrylamide-co-acrylic acid hydrogels. The nanocomposites chemical structure was characterized by Fourier Transform Infrared Spectroscopy (FT-IR). The FT-IR shows the typical bands due to the hydrogel and additionally the peaks at 1750 cm -1 and 1450 cm -1 that correspond to the carbon nanotubes incorporated into the polymer matrix. Mechanical properties and swelling measurements in different buffer solutions were also performed. The nanocomposites showed improved mechanical properties and a stronger pH-response. In order to evaluate antimicrobial activity, the growth and adhesion of Staphylococcus aureus to nanocomposites were studied. Cytocompatibility was also evaluated by MTT assay on MDCK and 3T3 cell lines. The nanocomposites were found to be cytocompatible and showed a reduced bacterial colonization. Copyright © 2018 Elsevier B.V. All rights reserved.

Hemostatic gauze based on chitosan and hydroquinone: preparation, characterization and blood coagulation evaluation.

PubMed

Cassano, Roberta; Di Gioia, Maria Luisa; Mellace, Silvia; Picci, Nevio; Trombino, Sonia

2017-11-07

This work concerns on the preparation and performance evaluation of a new chitosan hydroquinone based gauze for hemostatic use. Chitosan and hydroquinone were firstly connected by etherification and then linked to the pre-carboxylate gauze. The functionalized material and the chitosan-hydroquinone ether were characterized by Fourier Transform Infrared (FT-IR) Spectroscopy and Differential Scanning Calorimetry (DSC). FT-IR results showed that an esterification occurred on carboxylic group of the gauze. The gauze functionalization degree was also evaluated by volumetric analysis. The ether hydroquinone content was obtained by the Folin test. Moreover, the linkage between hydroquinone and chitosan was confirmed by nuclear magnetic resonance (NMR). The hemostatic activity of functionalized gauze was evaluated by dynamic blood clotting assays. The obtained results showed that the prepared material can shorten the blood clotting time and induce the adhesion and activation of platelets. Finally, swelling characteristic of the new gauze was evaluated to confirm its high capacity to absorb the blood.

Green Synthesis of Magnetite (Fe3O4) Nanoparticles Using Seaweed ( Kappaphycus alvarezii) Extract

NASA Astrophysics Data System (ADS)

Yew, Yen Pin; Shameli, Kamyar; Miyake, Mikio; Kuwano, Noriyuki; Bt Ahmad Khairudin, Nurul Bahiyah; Bt Mohamad, Shaza Eva; Lee, Kar Xin

2016-06-01

In this study, a simple, rapid, and eco-friendly green method was introduced to synthesize magnetite nanoparticles (Fe3O4-NPs) successfully. Seaweed Kappaphycus alvarezii ( K. alvarezii) was employed as a green reducing and stabilizing agents. The synthesized Fe3O4-NPs were characterized with X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared (FT-IR), and transmission electron microscopy (TEM) techniques. The X-ray diffraction planes at (220), (311), (400), (422), (511), (440), and (533) were corresponding to the standard Fe3O4 patterns, which showed the high purity and crystallinity of Fe3O4-NPs had been synthesized. Based on FT-IR analysis, two characteristic absorption peaks were observed at 556 and 423 cm-1, which proved the existence of Fe3O4 in the prepared nanoparticles. TEM image displayed the synthesized Fe3O4-NPs were mostly in spherical shape with an average size of 14.7 nm.

Green Synthesis of Magnetite (Fe3O4) Nanoparticles Using Seaweed (Kappaphycus alvarezii) Extract.

PubMed

Yew, Yen Pin; Shameli, Kamyar; Miyake, Mikio; Kuwano, Noriyuki; Bt Ahmad Khairudin, Nurul Bahiyah; Bt Mohamad, Shaza Eva; Lee, Kar Xin

2016-12-01

In this study, a simple, rapid, and eco-friendly green method was introduced to synthesize magnetite nanoparticles (Fe3O4-NPs) successfully. Seaweed Kappaphycus alvarezii (K. alvarezii) was employed as a green reducing and stabilizing agents. The synthesized Fe3O4-NPs were characterized with X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared (FT-IR), and transmission electron microscopy (TEM) techniques. The X-ray diffraction planes at (220), (311), (400), (422), (511), (440), and (533) were corresponding to the standard Fe3O4 patterns, which showed the high purity and crystallinity of Fe3O4-NPs had been synthesized. Based on FT-IR analysis, two characteristic absorption peaks were observed at 556 and 423 cm(-1), which proved the existence of Fe3O4 in the prepared nanoparticles. TEM image displayed the synthesized Fe3O4-NPs were mostly in spherical shape with an average size of 14.7 nm.

Immobilized copper(II) macrocyclic complex on MWCNTs with antibacterial activity

NASA Astrophysics Data System (ADS)

Tarlani, Aliakbar; Narimani, Khashayar; Mohammadipanah, Fatemeh; Hamedi, Javad; Tahermansouri, Hasan; Amini, Mostafa M.

2015-06-01

In a new approach, a copper(II) tetraaza macrocyclic complex (CuTAM) was covalently bonded on modified multi-walled carbon nanotubes (MWCNTs). To achieve this purpose, MWCNTs were converted to MWCNT-COCl and then reacted to NH groups of TAM ligand. The prepared material was characterized by Fourier Transform Infrared (FT-IR), X-ray diffraction (XRD), Raman spectroscopy, thermal gravimetric analysis (TGA), and FESEM (field emission scanning electron microscopy). FT-IR and TGA demonstrated the presence of the organic moieties, and XRD proved that the structure of MWCNTs remained intact during the three modification steps. An increase in the ID/IG ratio in Raman spectra confirmed the surface modifications. Finally, the samples were subjected to an antibacterial assessment to compare their biological activity. The antibacterial test showed that the grafted complex on the surface of the nanotube (MWCNT-CO-CuTAM) has higher antibacterial activity against Bacillus subtilis ATCC 6633 than the MWCNT-COOH and CuTAM with 1000 and 2000 μg/mL.

Photovoltaics module interface: General purpose primers

NASA Technical Reports Server (NTRS)

Boerio, J.

1985-01-01

The interfacial chemistry established between ethylene vinyl acetate (EVA) and the aluminized back surface of commercial solar cells was observed experimentally. The technique employed is called Fourier Transform Infrared (FTIR) spectroscopy, with the infrared signal being reflected back from the aluminum surface through the EVA film. Reflection infrared (IR) spectra are given and attention is drawn to the specific IR peak at 1080/cm which forms on hydrolytic aging of the EVA/aluminum system. With this fundamental finding, and the workable experimental techniques, candidate silane coupling agents are employed at the interface, and their effects on eliminating or slowing hydrolytic aging of the EVA/aluminum interface are monitored.

[The analyses and identification of Flos rhododendri mollis and Flos chrysanthemi indici via infrared spectroscopy].

PubMed

Jin, Zhe-Xiong; Wang, Yue; Zhou, Qun; Chen, Jian-Bo; Ma, Fang; Sun, Su-Qin

2014-09-01

In this study, major chemical components of Flos rhododendri mollis and Flos chrysanthemi indici were characterized using Fourier transform infrared spectroscopy (FTIR). For Flos rhododendri mollis, the bands at 1,648 and 1,543 cm(-1) were attributed to amide I and amide II , respectively, indicating that it contained proteins probably resulting in immunization. In case of Flos chrysanthemi indici, stretching vibration of C==O function group was responsible for the bands at 1,734 and 1,515 cm(-1), as a result of essential oils, lipids, etc. Since FTIR spectra of Flos rhododendri mollis and Flos chrysanthemi indici are almost identical and it is difficult to discriminate them, two-step identification was investigated via secondary derivative of the FTIR spectra. The bands at 1,656 and 1,515 cm(-1) corresponds to flavonoides in Flos rhododendri mollis and Flos chrysanthemi indici. In the secondary derivative of the FTIR spectrum of Flos chrysanthemi indici, characteristic bands of inulin were present at 1,163, 1,077, 1,026, 986 and 869 cm(-1), and therefore Flos chrysanthemi indici contained inulin as well. Tri-step identification was carried out for Flos rhododendri mollis and Flos chrysanthemi indici by means of comparing their 2D-IR correlation spectra in different wave number range. In the characteristic range of flavonoides (1,700-1,400 cm(-1)), Flos rhododendri mollis exhibited 3 obvious autopeaks, while 10 autopeaks were visualized in the 2D-IR correlation spectrum of Flos chrysanthemi indici Moreover, in the characteristic range of glucoside (1,250-900 cm(-1)), 10 and 9 autopeaks were present in the 2D-IR correlation spectra of Flos rhododendri mollis and Flos chrysanthemi indici, respectively. Therefore, the tri-step identification of FTIR is a time-saving; accurate, cost-saving and convenient method to effectively distinguish traditional Chinese medicines.

The study of the changes in the biochemical and mineral contents of bones of Catla catla due to lead intoxication.

PubMed

Palaniappan, P L R M; Krishnakumar, N; Vadivelu, M; Vijayasundaram, V

2010-02-01

In the present study, an attempt has been made to analyze the changes in the biochemical and mineral contents of lead-intoxicated bones of Catla catla at subchronic (15.5 ppm) exposure, and also to determine whether the effects of Pb intoxication can be reversed with the chelating agent meso 2, 3-dimercaptosuccinic acid (DMSA) on the bones of freshwater fingerlings Catla catla by using Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and atomic absorption spectrophotometer techniques. The FT-IR spectra of the lead-exposed bones show significant alteration in the biochemical constituents. The XRD analysis showed a decrease in crystallinity due to lead exposure. Further, the Ca, Mg, and P contents of the lead-exposed bones were less than those of the control group, and there was an increase in the mineral contents of the bones after DMSA treatment. In conclusion, the present study suggests that the subchronic lead exposure results in severe loss of bone minerals. The overall decrease in the FT-IR band intensity of Pb-exposed bones relative to the control indicates a decrease in the biochemical constituents like proteins and lipids. The increase in the band intensity after treatment with chelating agent DMSA indicates increased biochemical constituents, showing that the subchronic effects of lead can be reversed by DMSA. The amide I bands observed at 1654 cm(-1) in the present study suggest that the protein is dominated by alpha-helical structure.

Investigation of the interaction of 2,4-dimethoxy-6,7-dihydroxyphenanthrene with α-glucosidase using inhibition kinetics, CD, FT-IR and molecular docking methods.

PubMed

Zhang, Songsong; Qiu, Beibei; Zhu, Jinhua; Khan, M Z H; Liu, Xiuhua

2018-05-25

Applying enzyme kinetics, spectroscopic, and molecular docking methods, the interaction properties of 2,4-dimethoxy-6,7-dihydroxyphenanthrene with α-glucosidase were systematically investigated. The α-glucosidase inhibitory activities (IC 50  = 0.40 mM) were significantly higher than that of acarbose (as control) and the spectrometric results revealed that 2,4-dimethoxy-6,7-dihydroxyphenanthrene inhibited α-glucosidase in a reversible and noncompetitive manner, which is that the inhibitor bind to the inactive region of α-glucosidase and could be separated from the bind sites. Hydrogen bond was the key interaction force obtained from the results of the molecular docking study, and the binding energy was -27.754 kJ/mol. The CD studies showed that the content of α-helix in α-glucosidase increased from 17.2% to 17.8% with the concentration varying of 2,4-dimethoxy-6,7-dihydroxyphenanthrene. The α-helix increasing trend (19.70% - 21.43%) of α-glucosidase secondary structure was further proved by Fourier transform infrared spectra (FT-IR) results and the FT-IR spectra of α-glucosidase resulted in obvious red shift with the addition of 2,4-dimethoxy-6,7-dihydroxyphenanthrene. All the measurements proved the interaction of 2,4-dimethoxy-6,7-dihydroxyphenanthrene with α-glucosidase and revealed the conformational change of α-glucosidase secondary structure. Copyright © 2018 Elsevier B.V. All rights reserved.

Chicken, beams, and Campylobacter: rapid differentiation of foodborne bacteria via vibrational spectroscopy and MALDI-mass spectrometry.

PubMed

Muhamadali, Howbeer; Weaver, Danielle; Subaihi, Abdu; AlMasoud, Najla; Trivedi, Drupad K; Ellis, David I; Linton, Dennis; Goodacre, Royston

2016-01-07

Campylobacter species are one of the main causes of food poisoning worldwide. Despite the availability of established culturing and molecular techniques, due to the fastidious nature of these microorganisms, simultaneous detection and species differentiation still remains challenging. This study focused on the differentiation of eleven Campylobacter strains from six species, using Fourier transform infrared (FT-IR) and Raman spectroscopies, together with matrix-assisted laser desorption ionisation-time of flight-mass spectrometry (MALDI-TOF-MS), as physicochemical approaches for generating biochemical fingerprints. Cluster analysis of data from each of the three analytical approaches provided clear differentiation of each Campylobacter species, which was generally in agreement with a phylogenetic tree based on 16S rRNA gene sequences. Notably, although C. fetus subspecies fetus and venerealis are phylogenetically very closely related, using FT-IR and MALDI-TOF-MS data these subspecies were readily differentiated based on differences in the lipid (2920 and 2851 cm(-1)) and fingerprint regions (1500-500 cm(-1)) of the FT-IR spectra, and the 500-2000 m/z region of the MALDI-TOF-MS data. A finding that was further investigated with targeted lipidomics using liquid chromatography-mass spectrometry (LC-MS). Our results demonstrate that such metabolomics approaches combined with molecular biology techniques may provide critical information and knowledge related to the risk factors, virulence, and understanding of the distribution and transmission routes associated with different strains of foodborne Campylobacter spp.

Novel selenium containing boro-phosphate glasses: preparation and structural study.

PubMed

Ciceo-Lucacel, R; Radu, T; Ponta, O; Simon, V

2014-06-01

We synthesized a new boro-phosphate glass system with different %mol SeO2 content by conventional melt quenching technique. All samples were obtained in a glassy state with the vitreous structure confirmed by X-ray diffraction analysis. Scanning electron microscopy (SEM) revealed some non-homogeneous domains on the glasses surface, and their tendency to link each other once the selenium oxide content increases. Energy-dispersive X-ray analysis (EDAX) indicated similar elemental composition in different regions of each sample. X-ray photoelectron spectroscopy (XPS) was used to determine the nature of chemical bonding and the elemental composition at the sample surfaces, and Fourier transform infrared (FT-IR) spectroscopy was used to determine the structural groups in the obtained glass structure. Based on FT-IR results, the glass structure at short range order consists mainly of small phosphate units such as pyrophosphate (i.e. P2O7(4-) dimmers or terminating groups at the end of phosphate chains) and some metaphosphate (i.e. PO3(-) middle groups in the phosphate chains) units. The boron atoms are mainly placed in three-coordinated sites in BØ3 or BØ2O(-) units. A small contribution of BØ4(-) units was also detected from the FT-IR spectra of glasses. For SeO2 content higher than 5mol%, the modifier role of selenium ions is strongly reflected on the local structure dominated in this case by pyrophosphate units. Copyright © 2014 Elsevier B.V. All rights reserved.

Effects of scalp dermatitis on chemical property of hair keratin

NASA Astrophysics Data System (ADS)

Kim, Kyung Sook; Shin, Min Kyung; Park, Hun-Kuk

2013-05-01

The effects of scalp dermatitis (seborrheic dermatitis (SD), psoriasis, and atopic dermatitis (AD)) on chemical properties of hair keratin were investigated by Fourier transform infrared (FT-IR) spectroscopy. Hairs were collected from lesional regions affected by SD, psoriasis, and AD and non-lesional regions separately. The hairs with SD were taken from patients with ages of 16-80 years. The ages of patients with psoriasis ranged from 8 to 67 years, and all patients exhibited moderate disease. Hairs with AD were taken from the patients with ages of 24-45 years and the average SCORing atopic dermatitis (SCORAD) was 48.75. Hairs from 20 normal adults were collected as a control. The FT-IR absorbance bands were analyzed by the Gaussian model to obtain the center frequency, half width, height, and area of each band. The height and area of all bands in the spectra were normalized to the amide I centered at 1652 cm-1 to quantitatively analyze the chemical composition of keratin. The spectra of hair with scalp dermatitis were different with that of control, the amide A components centered at 3278 cm-1 were smaller than those of the control. The psoriasis hair showed a large difference in the IR absorbance band between lesional and non-lesional hairs indicating good agreement with the morphological changes. The hairs with diseases did not show differences in the content of cystine, which was centered at 1054 cm-1, from the control. The chemical properties of keratin were not significantly different between the hairs affected by SD, psoriasis, and AD. However, the changes induced by scalp dermatitis were different with weathering. Therefore, FT-IR analysis could be used to screen differences between the physiological and pathological conditions of scalp hair.

Advanced characterization of glass/melt inclusions trapped in phenocrysts by combined SEM-EDS, EMP-WDS and FT-IR techniques

NASA Astrophysics Data System (ADS)

Bellatreccia, Fabio; Cavallo, Andrea; de Astis, Gianfilippo; Della Ventura, Giancarlo; Mangiacapra, Annarita; Moretti, Roberto; Mormone, Angela; Piochi, Monica

2010-05-01

Melt inclusions (MIs) are micrometric-sized and variable-shaped impurity parcels of glass ± vesicles ± solids present within cavities or fractures of crystals. Because representing melt droplets that were trapped during crystal growth, they are believed to record the variable physico-chemical conditions of the hosting multi-phase system. Therefore, MIs are unique probe of near-liquidus magmatic conditions, otherwise inaccessible to Earth Scientists, and are widely used to integrate and corroborate conventional petrological and volcanological techniques based on mineral phases and whole rocks. Electron microprobe (EMP-WDS) and microscopy (SEM-EDS), and Fourier Transform Infra Red (FT-IR) spectroscopy are well-established analytical techniques, commonly used to determine composition of the magma from which MIs formed. Noteworthy, FT-IR is usually adopted to determine the content of dissolved H2O and CO2, providing i) essential information for entrapment pressures, hence depths of crystal growth, and ii) constraints to the volatile budget of magmas. Assessing such volatile contents has significant implications for the understanding of magma evolution and migration, from the depths of parental magma genesis, through the main depths of crustal storage, up to surface. The MI-based quantification of volatile contents and the recognition of degassing patterns are also vital for deciphering magma rheology, which largely affects eruptive dynamics and style. Limits to melt inclusion studies are i) their typically very small size (< 100 µm), ii) the possible late and secondary crystallization, iii) the diffusivity-driven chemical exchange between melt and host crystal, iv) and the alteration phenomena that mask or even delete the original melt composition. Here, we present a study of glass/melt inclusions in phenocrysts from Procida Island (Phlegraean Volcanic District, South Italy), analyzed for combined SEM-EDS electron microscopy, EMP-WDS microchemistry and FT-IR spectroscopy. In particular, we have characterized the distribution of volatile H and C species across both the host crystals and the inclusions, by using a focal-plane-array (FPA) of detectors. The FPA technique allows the acquisition of a large number of IR spectra simultaneously and generate mid-IR images with high resolving power of the target molecules in the H-O-C system. The integration of these analytical techniques is a mandatory step in order to provide definite advances in MI characterization and data interpretation.

Detection of creatinine enriched on a surface imprinted polystyrene film using FT-ATR-IR.

PubMed

Sreenivasan, K

2006-01-01

The surface of polystyrene (PS) was chemically modified by coating a thin layer of polyaniline (PANI) by oxidizing aniline using ammonium persulfate. Affinity sites for creatinine, a clinically relevant molecule, were created in the coated layer by adding creatinine as print molecules during the oxidation. The imprinted layer adsorbed creatinine was compared to non-imprinted surface reflecting the creation of creatinine-specific sites on the surface. The equilibrium was attained rapidly, indicating that a material of this kind is suitable for sensing applications. The adsorbed creatinine on the surface was detected using the technique of Fourier transform attenuated total internal reflection infra red spectroscopy (FT-ATR-IR). The results show that molecularly imprinted surface can enrich molecules of interest and the enriched molecules can be detected using FT-IR.

Formation of insulin amyloid fibrils followed by FTIR simultaneously with CD and electron microscopy.

PubMed Central

Bouchard, M.; Zurdo, J.; Nettleton, E. J.; Dobson, C. M.; Robinson, C. V.

2000-01-01

Fourier transform infrared spectroscopy (FTIR), circular dichroism (CD), and electron microscopy (EM) have been used simultaneously to follow the temperature-induced formation of amyloid fibrils by bovine insulin at acidic pH. The FTIR and CD data confirm that, before heating, insulin molecules in solution at pH 2.3 have a predominantly native-like alpha-helical structure. On heating to 70 degrees C, partial unfolding occurs and results initially in aggregates that are shown by CD and FT-IR spectra to retain a predominantly helical structure. Following this step, changes in the CD and FTIR spectra occur that are indicative of the extensive conversion of the molecular conformation from alpha-helical to beta-sheet structure. At later stages, EM shows the development of fibrils with well-defined repetitive morphologies including structures with a periodic helical twist of approximately 450 A. The results indicate that formation of fibrils by insulin requires substantial unfolding of the native protein, and that the most highly ordered structures result from a slow evolution of the morphology of the initially formed fibrillar species. PMID:11106169

FT-IR spectrum of grape seed oil and quantum models of fatty acids triglycerides

NASA Astrophysics Data System (ADS)

Berezin, K. V.; Antonova, E. M.; Shagautdinova, I. T.; Chernavina, M. L.; Dvoretskiy, K. N.; Grechukhina, O. N.; Vasilyeva, L. M.; Rybakov, A. V.; Likhter, A. M.

2018-04-01

FT-IR spectra of grape seed oil and glycerol were registered in the 650-4000 cm-1 range. Molecular models of glycerol and some fatty acids that compose the oil under study - linoleic, oleic, palmitic and stearic acids - as well as their triglycerides were developed within B3LYP/6-31G(d) density functional model. A vibrating FT-IR spectrum of grape seed oil was modeled on the basis of calculated values of vibrating wave numbers and IR intensities of the fatty acids triglycerides and with regard to their percentage. Triglyceride spectral bands that were formed by glycerol linkage vibrations were revealed. It was identified that triglycerol linkage has a small impact on the structure of fatty acids and, consequently, on vibrating wave numbers. The conducted molecular modeling became a basis for theoretical interpretation on 10 experimentally observed absorption bands in FT-IR spectrum of grape seed oil.

Investigation of the Cross-Section Stratifications of Icons Using Micro-Raman and Micro-Fourier Transform Infrared (FT-IR) Spectroscopy.

PubMed

Lazidou, Dimitra; Lampakis, Dimitrios; Karapanagiotis, Ioannis; Panayiotou, Costas

2018-01-01

The cross-section stratifications of samples, which were removed from six icons, are studied using optical microscopy, micro-Raman spectroscopy, and micro-Fourier transform infrared (FT-IR) spectroscopy. The icons, dated from the 14th to 19th centuries, are prominent examples of Byzantine painting art and are attributed to different artistic workshops of ​​northern Greece. The following materials are identified in the cross-sections of the icon samples using micro-Raman spectroscopy: anhydrite; calcite; carbon black; chrome yellow; cinnabar; gypsum; lead white; minium; orpiment; Prussian blue; red ochre; yellow ochre; and a paint of organic origin which can be either indigo ( Indigofera tinctoria L. and others) or woad ( Isatis tinctoria L.). The same samples are investigated using micro-FT-IR which leads to the following identifications: calcite; calcium oxalates; chrome yellow; gypsum; kaolinite; lead carboxylates; lead sulfate (or quartz); lead white; oil; protein; Prussian blue; saponified oil; shellac; silica; and tree resin. The study of the cross-sections of the icon samples reveals the combinations of the aforementioned inorganic and organic materials. Although the icons span over a long period of six centuries, the same stratification comprising gypsum ground layer, paint layers prepared by modified "egg tempera" techniques (proteinaceous materials mixed with oil and resins), and varnish layer is revealed in the investigated samples. Moreover, the presence of three layers of varnishes, one at the top and other two as intermediate layers, in the cross-section analysis of a sample from Virgin and Child provide evidence of later interventions.

Spectroscopic characterization of enzymatic flax retting: Factor analysis of FT-IR and FT-Raman data

NASA Astrophysics Data System (ADS)

Archibald, D. D.; Henrikssen, G.; Akin, D. E.; Barton, F. E.

1998-06-01

Flax retting is a chemical, microbial or enzymatic process which releases the bast fibers from the stem matrix so they can be suitable for mechanical processing before spinning into linen yarn. This study aims to determine the vibrational spectral features and sampling methods which can be used to evaluate the retting process. Flax stems were retted on a small scale using an enzyme mixture known to yield good retted flax. Processed stems were harvested at various time points in the process and the retting was evaluated by conventional methods including weight loss, color difference and Fried's test, a visual ranking of how the stems disintegrate in hot water. Spectroscopic measurements were performed on either whole stems or powders of the fibers that were mechanically extracted from the stems. Selected regions of spectra were baseline and amplitude corrected using a variant of the multiplicative signal correction method. Principal component regression and partial least-squares regression with full cross-validation were used to determine the spectral features and rate of spectral transformation by regressing the spectra against the retting time in hours. FT-Raman of fiber powders and FT-IR reflectance of whole stems were the simplest and most precise methods for monitoring the retting transformation. Raman tracks the retting by measuring the decrease in aromatic signal and subtle changes in the C-H stretching vibrations. The IR method uses complex spectral features in the fingerprint and carbonyl region, many of which are due to polysaccharide components. Both spectral techniques monitor the retting process with greater precision than the reference method.

Soil Organic Carbon Degradation during Incubation, Barrow, Alaska, 2012

DOE Data Explorer

Elizabeth Herndon; Ziming Yang; Baohua Gu

2017-01-05

This dataset provides information about soil organic carbon decomposition in Barrow soil incubation studies. The soil cores were collected from low-center polygon (Area A) and were incubated in the laboratory at different temperatures for up to 60 days. Transformations of soil organic carbon were characterized by UV and FT-IR, and small organic acids in water-soluble carbons were quantified by ion chromatography during the incubation (Herndon et al., 2015).

Longitudinal Plasmoid in High-Speed Vortex Gas Flow Created by Capacity HF Discharge

DTIC Science & Technology

2010-10-28

interferometer with high space resolution, PIV method, FTIR spectrometer, optical spectrometer, pressure sensors with high time resolution, IR pyrometer and...of strong LP-vortex interaction. Intensive acoustic waves are created by CHFD in swirl flow in this regime. 38. Study of control of a longitudinal...quartz tube, 4- HF ball electrode, 5- Tesla’s transformer, 6- microwave interferometer, 7- video camera, 8-optical pyrometer , 9-pressure sensor, 10

Multispectral Observations of Explosive Gas Emissions from Santiaguito, Guatemala

NASA Astrophysics Data System (ADS)

Carn, S. A.; Watson, M.; Thomas, H.; Rodriguez, L. A.; Campion, R.; Prata, F. J.

2016-12-01

Santiaguito volcano, Guatemala, has been persistently active for decades, producing frequent explosions from its actively growing lava dome. Repeated release of volcanic gases contains information about conduit processes during the cyclical explosions at Santiaguito, but the composition of the gas phase and the amount of volatiles released in each explosion remains poorly constrained. In addition to its persistent activity, Santiaguito offers an exceptional opportunity to investigate lava dome degassing processes since the upper surface of the active lava dome can be viewed from the summit of neighboring Santa Maria. In January 2016 we conducted multi-spectral observations of Santiaguito's explosive eruption plumes and passive degassing from multiple perspectives as part of the first NSF-sponsored `Workshop on Volcanoes' instrument deployment. Gas measurements included open-path Fourier-Transform infrared (OP-FTIR) spectroscopy from the Santa Maria summit, coincident with ultraviolet (UV) and infrared (IR) camera and UV Differential Optical Absorption Spectroscopy (DOAS) from the El Mirador site below Santiaguito's active Caliente lava dome. Using the OP-FTIR in passive mode with the Caliente lava dome as the source of IR radiation, we were able to collect IR spectra at high temporal resolution prior to and during two explosions of Santiaguito on 7-8 January, with volcanic SO2 and H2O emissions detected. UV and IR camera data provide constraints on the total SO2 burden in the emissions (and potentially the volcanic ash burden), which coupled with the FTIR gas ratios provides new constraints on the mass and composition of volatiles driving explosions at Santiaguito. All gas measurements indicate significant volatile release during explosions with limited degassing during repose periods. In this presentation we will present ongoing analysis of the unique Santiaguito gas dataset including estimation of the total volatile mass released in explosions and an intercomparison of SO2 amounts recorded by the UV and IR instruments.

Sculpting narrowband Fano resonances inherent in the large-area mid-infrared photonic crystal microresonators for spectroscopic imaging

PubMed Central

Liu, Jui-Nung; Schulmerich, Matthew V.; Bhargava, Rohit; Cunningham, Brian T.

2014-01-01

Fourier transform infrared (FT-IR) imaging spectrometers are almost universally used to record microspectroscopic imaging data in the mid-infrared (mid-IR) spectral region. While the commercial standard, interferometry necessitates collection of large spectral regions, requires a large data handling overhead for microscopic imaging and is slow. Here we demonstrate an approach for mid-IR spectroscopic imaging at selected discrete wavelengths using narrowband resonant filtering of a broadband thermal source, enabled by high-performance guided-mode Fano resonances in one-layer, large-area mid-IR photonic crystals on a glass substrate. The microresonant devices enable discrete frequency IR (DF-IR), in which a limited number of wavelengths that are of interest are recorded using a mechanically robust instrument. This considerably simplifies instrumentation as well as overhead of data acquisition, storage and analysis for large format imaging with array detectors. To demonstrate the approach, we perform DF-IR spectral imaging of a polymer USAF resolution target and human tissue in the C−H stretching region (2600−3300 cm−1). DF-IR spectroscopy and imaging can be generalized to other IR spectral regions and can serve as an analytical tool for environmental and biomedical applications. PMID:25089433

Infrared Spectroscopy as a Tool to Study the Antioxidant Activity of Polyphenolic Compounds in Isolated Rat Enterocytes

PubMed Central

Barraza-Garza, Guillermo; Castillo-Michel, Hiram; de la Rosa, Laura A.; Martinez-Martinez, Alejandro; Pérez-León, Jorge A.; Cotte, Marine; Alvarez-Parrilla, Emilio

2016-01-01

The protective effect of different polyphenols, catechin (Cat), quercetin (Qc) (flavonoids), gallic acid (GA), caffeic acid (CfA), chlorogenic acid (ChA) (phenolic acids), and capsaicin (Cap), against H2O2-induced oxidative stress was evaluated in rat enterocytes using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) Spectroscopy and Fourier Transform Infrared Microspectroscopy (FTIRM), and results were compared to standard lipid peroxidation techniques: conjugated dienes (CD) and Thiobarbituric Acid Reactive Substances (TBARS). Analysis of ATR-FTIR and FTIRM spectral data allowed the simultaneous evaluation of the effects of H2O2 and polyphenols on lipid and protein oxidation. All polyphenols showed a protective effect against H2O2-induced oxidative stress in enterocytes, when administered before or after H2O2. Cat and capsaicin showed the highest protective effect, while phenolic acids had weaker effects and Qc presented a mild prooxidative effect (IR spectral profile of biomolecules between control and H2O2-treated cells) according to FTIR analyses. These results demonstrated the viability to use infrared spectroscopy to evaluate the oxidant and antioxidant effect of molecules in cell systems assays. PMID:27213031

FT-IR spectroscopy study on cutaneous neoplasie

NASA Astrophysics Data System (ADS)

Crupi, V.; De Domenico, D.; Interdonato, S.; Majolino, D.; Maisano, G.; Migliardo, P.; Venuti, V.

2001-05-01

In this work we report a preliminary study of Fourier transform infrared spectroscopy on normal and neoplastic human skin samples suffering from two kinds of cancer, namely epithelioma and basalioma. The analyzed skin samples have been drawn from different parts of the human body, after biopsies. By performing a complex band deconvolution due to the complexity of the tissue composition, the analysis within the considered frequency region (900-4000 cm -1) of the collected IR spectra, allowed us, first of all, to characterize the presence of the pathologies and to show clear different spectral features passing from the normal tissue to the malignant one in particular within the region (1500-2000 cm -1) typical of the lipid bands.

Solution combustion method for synthesis of nanostructured hydroxyapatite, fluorapatite and chlorapatite

NASA Astrophysics Data System (ADS)

Zhao, Junjie; Dong, Xiaochen; Bian, Mengmeng; Zhao, Junfeng; Zhang, Yao; Sun, Yue; Chen, JianHua; Wang, XuHong

2014-09-01

Hydroxyapatite (HAP), fluorapatite (Fap) and chlorapatite (Clap) were prepared by solution combustion method with further annealing at 800 °C. The characterization and structural features of the synthesized powders were evaluated by the powder X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and transmission electron microscopy (TEM) techniques. Characterization results from XRD and Rietveld analysis revealed that OH- in the HAP lattice were gradually substituted with the increase of F- and Cl- content and totally substituted at the molar concentration of 0.28 and 0.6, respectively. The results from FI-IR have also confirmed the incorporation of substituted anions in the apatite structure.

FT-IR SOLUTION SPECTRA OF PROPYL SULFIDE, PROPYL SULFOXIDE, AND PROPYL SULFONE

EPA Science Inventory

FT-IR spectra were obtained of 0.5% volumetric solutions of propyl sulfide, propyl sulfoxide, and propyl sulfone in hexane, CCl4, CS2, and CHCl3 to assist in the assignment of FT-IR-PAS spectra of propyl sulfoxide sorbed within the structure of several peats and onto cellulose. T...

[Revisiting the chemical diversity in prostatic calculi: a SEM and FT-IR investigation].

PubMed

Dessombz, A; Méria, P; Bazin, D; Foy, E; Rouzière, S; Weil, R; Daudon, M

2011-12-01

Revisiting the chemical diversity of the crystalline phases of prostatic calculi by means of SEM and FT-IR analysis. A set of 32 prostatic calculi has been studied by FT-IR and SEM. FT-IR analysis has determined the chemical composition of each prostatic calculus and the SEM observation has described the morphology of the calculi surfaces and layers. Infrared analysis revealed that 90.7% of the stones were mainly composed of calcium phosphates. However, several mineral phases previously not reported in prostatic calculi were observed, as brushite or octocalcium phosphate pentahydrate. Prostatic calculi exhibited a diversity of crystalline composition and morphology. As previously reported for urinary calculi, relationships between composition and morphology of prostatic stones and étiopathogenic conditions could be of interest in clinical practice. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Cleanliness evaluation of rough surfaces with diffuse IR reflectance

NASA Technical Reports Server (NTRS)

Pearson, L. H.

1995-01-01

Contamination on bonding surfaces has been determined to be a primary cause for degraded bond strength in certain solid rocket motor bondlines. Hydrocarbon and silicone based organic contaminants that are airborne or directly introduced to a surface are a significant source of contamination. Diffuse infrared (IR) reflectance has historically been used as an effective technique for detection of organic contaminants, however, common laboratory methods involving the use of a Fourier transform IR spectrometer (FTIR) are impractical for inspecting the large bonding surface areas found on solid rocket motors. Optical methods involving the use of acousto-optic tunable filters and fixed bandpass optical filters are recommended for increased data acquisition speed. Testing and signal analysis methods are presented which provide for simultaneous measurement of contamination concentration and roughness level on rough metal surfaces contaminated with hydrocarbons.

Discrimination of edible oils and fats by combination of multivariate pattern recognition and FT-IR spectroscopy: A comparative study between different modeling methods

NASA Astrophysics Data System (ADS)

Javidnia, Katayoun; Parish, Maryam; Karimi, Sadegh; Hemmateenejad, Bahram

2013-03-01

By using FT-IR spectroscopy, many researchers from different disciplines enrich the experimental complexity of their research for obtaining more precise information. Moreover chemometrics techniques have boosted the use of IR instruments. In the present study we aimed to emphasize on the power of FT-IR spectroscopy for discrimination between different oil samples (especially fat from vegetable oils). Also our data were used to compare the performance of different classification methods. FT-IR transmittance spectra of oil samples (Corn, Colona, Sunflower, Soya, Olive, and Butter) were measured in the wave-number interval of 450-4000 cm-1. Classification analysis was performed utilizing PLS-DA, interval PLS-DA, extended canonical variate analysis (ECVA) and interval ECVA methods. The effect of data preprocessing by extended multiplicative signal correction was investigated. Whilst all employed method could distinguish butter from vegetable oils, iECVA resulted in the best performances for calibration and external test set with 100% sensitivity and specificity.

FT-IR and µ-IR characterization of HED meteorites in relation to infrared spectra of Vesta-like asteroids

NASA Astrophysics Data System (ADS)

Ferrari, M.; Dirri, F.; Palomba, E.; Stefani, S.; Longobardo, A.; Rotundi, A.

2017-09-01

We present the results of the FT-IR and µ-IR study of three Howardite-Eucrite-Diogenite meteorites (HEDs) compared to the spectroscopic data collected by VIR onboard Dawn spacecraft. The origin of this group of achondrites is thought to be linked to the asteroid 4 Vesta, hypothesis lately reinforced by the data provided by the Dawn mission.

Chemical Structural Characteristics of HULIS and Other Fractionated Organic Matter in Urban Aerosols: Results from Mass Spectral and FT-IR Analysis.

PubMed

Chen, Qingcai; Ikemori, Fumikazu; Higo, Hayato; Asakawa, Daichi; Mochida, Michihiro

2016-02-16

The chemical characteristics of complex organic matter in atmospheric aerosols remain poorly understood. Water-insoluble organic matter (WISOM) and water-soluble organic matter (WSOM) in the total suspended particulates collected in the city of Nagoya in summer/early autumn and winter were extracted using multiple solvents. Two fractions of humic-like substances, showing neutral and acidic behavior (HULIS-n and HULIS-a, respectively), and the remaining highly polar part (HP-WSOM) were fractionated from WSOM using solid phase extraction. The chemical structural characteristics and concentrations of the organic matter were investigated using mass spectrometry and Fourier transform infrared (FT-IR) spectroscopy. WISOM and HULIS-n had low O/C ratios (0.1 and 0.4, respectively) and accounted for a large fraction of the organics in aerosols (70%). HULIS-a and HP-WSOM had higher O/C ratios (0.7 and 1.0, respectively), and their concentrations in summer and early autumn were on average ∼2 times higher than those in winter. The mass spectrum and FT-IR analyses suggest the following: (1) WISOM were high-molecular-weight aliphatics (primarily C27-C32) with small proportions of -CH3, -OH, and C═O groups; (2) HULIS-n was abundant in aliphatic structures and hydroxyl groups (primarily C9-C18) and by branched structures; (3) HULIS-a and HP-WSOM contained relatively large amounts of low-molecular-weight carboxylic acids and alcohols (primarily C4-C10); and (4) WISOM and HULIS-n were relatively abundant in amines and organic nitrates.

Development of functionalized hydroxyapatite/poly(vinyl alcohol) composites

NASA Astrophysics Data System (ADS)

Stipniece, Liga; Salma-Ancane, Kristine; Rjabovs, Vitalijs; Juhnevica, Inna; Turks, Maris; Narkevica, Inga; Berzina-Cimdina, Liga

2016-06-01

Based on the well-known pharmaceutical excipient potential of poly(vinyl alcohol) (PVA) and clinical success of hydroxyapatite (HAp), the objective of this work was to fabricate functionalized composite microgranules. PVA was modified with succinic anhydride to introduce carboxyl groups (-COOH), respectively, by reaction between the -OH groups of PVA and succinic anhydride, for attachment of drug molecules. For the first time, the functionalized composite microgranules containing HAp/PVA in the ratio of 1:1 were prepared through in situ precipitation of HAp in modified PVA aqueous solutions followed by spray drying of obtained suspensions. The microgranules were characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and differential scanning calorimetry (DSC). The presence of -COOH groups was verified by FT-IR, and the amount of functional groups added to PVA molecules (averaging 15 mol%) was determined by nuclear magnetic resonance spectroscopy (NMR). DSC results showed that modification with -COOH groups slightly decreased the thermal stability of PVA. FT-IR and XRD analysis confirmed that the resulting composites contain mainly nanocrystalline HAp and PVA. Moreover, the images taken by FE-SEM revealed that the microgranules consisted of nanosized HAp crystallites homogenously embedded in the PVA matrix. DSC measurements indicated that decomposition mechanism of the HAp/PVA differs from that of pure PVA and occurs at lower temperatures. However, the presence of HAp had minor influence on the thermal decomposition of the PVA modified with succinic anhydride. The investigation of composite microgranules confirmed interaction and integration between the HAp and PVA.

Preparation and characterization of NiW-nHA composite catalyst for hydrocracking

NASA Astrophysics Data System (ADS)

Zhou, Gang; Hou, Yongzhao; Liu, Lei; Liu, Hongru; Liu, Can; Liu, Jing; Qiao, Huiting; Liu, Wenyong; Fan, Yubo; Shen, Shituan; Rong, Long

2012-11-01

The synthesis, characterization and catalytic capability of the NiW-nano-hydroxyapatite (NiW-nHA) composite were investigated in this paper. The NiW-nHA catalyst was prepared by a co-precipitation method. Then Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDX) were used to analyze this material. In addition, the catalytic capacity of the NiW-nHA composite was also examined by FT-IR and gas chromatography (GC). The results of FT-IR analysis indicated that Ni, W and nHA combined closely. TEM observation revealed that this catalyst was needle shaped and the crystal retained a nanometer size. XRD data also suggested that a new phase of CaWO4 appeared and the lattice parameters of nHA changed in this system. nHA was the carrier of metals. The rates of Ni/W-loading were 73.24% and 65.99% according to the EDX data, respectively. Furthermore, the conversion of 91.88% Jatropha oil was achieved at 360 °C and 3 MPa h-1 over NiW-nHA catalyst. The straight chain alkanes ranging from C15 to C18 were the main components in the production. The yield of C15-C18 alkanes was up to 83.56 wt%. The reaction pathway involved hydrocracking of the C&z.dbd;C bonds of these triglycerides from Jatropha oil. This paper developed a novel non-sulfided catalyst to obtain a ``green biofuel'' from vegetable oil.

Factors influencing preparation of polyaniline doped with hydrochloric acid

NASA Astrophysics Data System (ADS)

Chuanyu, Sun; Yu, Wang

2014-12-01

Factors influencing the reaction of chemical polymerization during aniline doping with hydrochloric acid (HCl) have been studied in this work. The optimal parameters for the preparation of polyaniline were determined as follows: aniline concentration - 4 mass %, molar ratios of oxidant (NH4)2S2O8:aniline - 1.2:1 and 1.3:1, the concentration of dopant - 1 mol/L. Fourier transform infrared spectroscopy (FT-IR) was applied to characterize the structure of polyaniline.

High-Resolution FTIR Spectrum of the ν 12 Band of trans- d2-Ethylene

NASA Astrophysics Data System (ADS)

Teo, H. H.; Ong, P. P.; Tan, T. L.; Goh, K. L.

2000-11-01

The ν12 band of trans-d2-ethylene (trans-C2H2D2) has been recorded with an unapodized resolution of 0.0024 cm-1 in the frequency range of 1240-1360 cm-1 by Fourier transform infrared (FTIR) spectroscopy. This band was found to be relatively free from any local frequency perturbations. By fitting a total of 1185 infrared transitions of ν12 with a standard deviation of 0.00043 cm-1 using a Watson's A-reduced Hamiltonian in the Ir representation, a set of accurate rovibrational constants for v12 = 1 state was derived. The ν12 band is A type with a band center at 1298.03797 ± 0.00004 cm-1.

Fourier Transform Infrared Spectroscopy and Photoacoustic Spectroscopy for Saliva Analysis.

PubMed

Mikkonen, Jopi J W; Raittila, Jussi; Rieppo, Lassi; Lappalainen, Reijo; Kullaa, Arja M; Myllymaa, Sami

2016-09-01

Saliva provides a valuable tool for assessing oral and systemic diseases, but concentrations of salivary components are very small, calling the need for precise analysis methods. In this work, Fourier transform infrared (FT-IR) spectroscopy using transmission and photoacoustic (PA) modes were compared for quantitative analysis of saliva. The performance of these techniques was compared with a calibration series. The linearity of spectrum output was verified by using albumin-thiocyanate (SCN(-)) solution at different SCN(-) concentrations. Saliva samples used as a comparison were obtained from healthy subjects. Saliva droplets of 15 µL were applied on the silicon sample substrate, 6 drops for each specimen, and dried at 37 ℃ overnight. The measurements were carried out using an FT-IR spectrometer in conjunction with an accessory unit for PA measurements. The findings with both transmission and PA modes mirror each other. The major bands presented were 1500-1750 cm(-1) for proteins and 1050-1200 cm(-1) for carbohydrates. In addition, the distinct spectral band at 2050 cm(-1) derives from SCN(-) anions, which is converted by salivary peroxidases to hypothiocyanate (OSCN(-)). The correlation between the spectroscopic data with SCN(-) concentration (r > 0.990 for transmission and r = 0.967 for PA mode) was found to be significant (P < 0.01), thus promising to be utilized in future applications. © The Author(s) 2016.

Digital filtering implementations for the detection of broad spectral features by direct analysis of passive Fourier transform infrared interferograms.

PubMed

Tarumi, Toshiyasu; Small, Gary W; Combs, Roger J; Kroutil, Robert T

2004-04-01

Finite impulse response (FIR) filters and finite impulse response matrix (FIRM) filters are evaluated for use in the detection of volatile organic compounds with wide spectral bands by direct analysis of interferogram data obtained from passive Fourier transform infrared (FT-IR) measurements. Short segments of filtered interferogram points are classified by support vector machines (SVMs) to implement the automated detection of heated plumes of the target analyte, ethanol. The interferograms employed in this study were acquired with a downward-looking passive FT-IR spectrometer mounted on a fixed-wing aircraft. Classifiers are trained with data collected on the ground and subsequently used for the airborne detection. The success of the automated detection depends on the effective removal of background contributions from the interferogram segments. Removing the background signature is complicated when the analyte spectral bands are broad because there is significant overlap between the interferogram representations of the analyte and background. Methods to implement the FIR and FIRM filters while excluding background contributions are explored in this work. When properly optimized, both filtering procedures provide satisfactory classification results for the airborne data. Missed detection rates of 8% or smaller for ethanol and false positive rates of at most 0.8% are realized. The optimization of filter design parameters, the starting interferogram point for filtering, and the length of the interferogram segments used in the pattern recognition is discussed.

The investigation of the effect of thermal treatment on bentonites from Turkey with Fourier transform infrared and solid state nuclear magnetic resonance spectroscopic methods.

PubMed

Erdoğan Alver, Burcu; Alver, Ozgür

2012-08-01

There is a great deal of interest in the building industry in burned clays for production of building materials. Therefore, the effect of heat treatment on natural bentonite from Turkey was investigated by Fourier transform infrared (FT-IR) between the region of 4000-400cm(-1) and (29)Si, (27)Al magic angle spinning nuclear magnetic resonance (MAS NMR) measurement techniques at various temperatures between 200 and 700°C for 2h. The structural changes were also investigated upon heat treatment. Copyright © 2012 Elsevier B.V. All rights reserved.

Optimally designed narrowband guided-mode resonance reflectance filters for mid-infrared spectroscopy

PubMed Central

Liu, Jui-Nung; Schulmerich, Matthew V.; Bhargava, Rohit; Cunningham, Brian T.

2011-01-01

An alternative to the well-established Fourier transform infrared (FT-IR) spectrometry, termed discrete frequency infrared (DFIR) spectrometry, has recently been proposed. This approach uses narrowband mid-infrared reflectance filters based on guided-mode resonance (GMR) in waveguide gratings, but filters designed and fabricated have not attained the spectral selectivity (≤ 32 cm−1) commonly employed for measurements of condensed matter using FT-IR spectroscopy. With the incorporation of dispersion and optical absorption of materials, we present here optimal design of double-layer surface-relief silicon nitride-based GMR filters in the mid-IR for various narrow bandwidths below 32 cm−1. Both shift of the filter resonance wavelengths arising from the dispersion effect and reduction of peak reflection efficiency and electric field enhancement due to the absorption effect show that the optical characteristics of materials must be taken into consideration rigorously for accurate design of narrowband GMR filters. By incorporating considerations for background reflections, the optimally designed GMR filters can have bandwidth narrower than the designed filter by the antireflection equivalence method based on the same index modulation magnitude, without sacrificing low sideband reflections near resonance. The reported work will enable use of GMR filters-based instrumentation for common measurements of condensed matter, including tissues and polymer samples. PMID:22109445

Bacterial cellulose may provide the microbial-life biosignature in the rock records

NASA Astrophysics Data System (ADS)

Zaets, I.; Podolich, O.; Kukharenko, O.; Reshetnyak, G.; Shpylova, S.; Sosnin, M.; Khirunenko, L.; Kozyrovska, N.; de Vera, J.-P.

2014-03-01

Bacterial cellulose (BC) is a matrix for a biofilm formation, which is critical for survival and persistence of microbes in harsh environments. BC could play a significant role in the formation of microbial mats in pristine ecosystems on Earth. The prime objective of this study was to measure to what extent spectral and other characteristics of BC were changed under the performance of BC interaction with the earthly rock - anorthosite - via microorganisms. The spectral analyses (Fourier Transform Infrared FT-IR, spectroscopy, and atomic absorption spectroscopy) showed unprecedented accumulation of chemical elements in the BC-based biofilm. The absorption capacity of IR by BC was shielded a little by mineral crust formed by microorganisms on the BC-based biofilm surface, especially clearly seen in the range of 1200-900 cm-1 in FT-IR spectra. Confocal scanning laser microscopy analysis revealed that elements bioleached from anorthosite created surface coats on the BC nanofibril web. At the same time, the vibrational spectra bands showed the presence of the characteristic region of anomeric carbons (960-730 cm-1), wherein a band at 897 cm-1 confirmed the presence of β-1, 4-linkages, which may serve as the cellulose fingerprint region. Results show that BC may be a biosignature for search signs of living organisms in rock records.

Simultaneous determination of some artificial sweeteners in ternary formulations by FT-IR and EI-MS

NASA Astrophysics Data System (ADS)

Tosa, Nicoleta; Moldovan, Zaharie; Bratu, Ioan

2012-02-01

Artificial sweeteners are widely used in food, beverage and pharmaceutical industries all over the world. In this study some non-nutritive sweeteners such as aspartame, acesulfame-K, sodium cyclamate and sodium saccharin were simultaneously determined in ternary mixtures using FT-IR and EI-MS measurements. FT-IR method is based on direct measurements of the peak height values and area centered on 1736 cm-1, 836 cm-1, 2854 cm-1 and 1050 cm-1 for aspartame, acesulfame-K, sodium cyclamate and sodium saccharin, respectively. Mass spectrometry determinations show the characteristic peaks at m/z 91 and 262 for aspartame,m/z 43 and 163 acesulfame-K,m/z 83 and 97 for sodium cyclamate andm/z 104 and 183 for sodium saccharin. The results obtained by EI-MS in different formulations are in agreement with the FT-IR ones and provide also essential data concerning the purity grade of the components. It is concluded that FT-IR and EI-MS procedures developed in this work represent a fast, sensitive and low cost alternative in the quality control of such sweeteners in different ternary formulations.

Penetration kinetics of dimethyl sulphoxide and glycerol in dynamic optical clearing of porcine skin tissue in vitro studied by Fourier transform infrared spectroscopic imaging.

PubMed

Jiang, Jingying; Boese, Matthias; Turner, Paul; Wang, Ruikang K

2008-01-01

By use of a Fourier transform infrared (FTIR) spectroscopic imaging technique, we examine the dynamic optical clearing processes occurring in hyperosmotically biocompatible agents penetrating into skin tissue in vitro. The sequential collection of images in a time series provides an opportunity to assess penetration kinetics of dimethyl sulphoxide (DMSO) and glycerol beneath the surface of skin tissue over time. From 2-D IR spectroscopic images and 3-D false color diagrams, we show that glycerol takes at least 30 min to finally penetrate the layer of epidermis, while DMSO can be detected in epidermis after only 4 min of being topically applied over stratum corneum sides of porcine skin. The results demonstrate the potential of a FTIR spectroscopic imaging technique as an analytical tool for the study of dynamic optical clearing effects when the bio-tissue is impregnated by hyperosmotically biocompatible agents such as glycerol and DMSO.

Fourier-transform infrared spectroscopy (FTIR) analysis of triclinic and hexagonal birnessites

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

Ling, Florence T.; Post, Jeffrey E.; Heaney, Peter J.

The characterization of birnessite structures is particularly challenging for poorly crystalline materials of biogenic origin, and a determination of the relative concentrations of triclinic and hexagonal birnessite in a mixed assemblage has typically required synchrotron-based spectroscopy and diffraction approaches. In this study, Fourier-transform infrared spectroscopy (FTIR) is demonstrated to be capable of differentiating synthetic triclinic Na-birnessite and synthetic hexagonal H-birnessite. Furthermore, IR spectral deconvolution of peaks resulting from Mnsingle bondO lattice vibrations between 400 and 750 cm - 1 yield results comparable to those obtained by linear combination fitting of synchrotron X-ray absorption fine structure (EXAFS) data when applied tomore » known mixtures of triclinic and hexagonal birnessites. Density functional theory (DFT) calculations suggest that an infrared absorbance peak at ~ 1628 cm - 1 may be related to OH vibrations near vacancy sites. The integrated intensity of this peak may show sensitivity to vacancy concentrations in the Mn octahedral sheet for different birnessites.« less

Fourier transform ion cyclotron resonance mass spectrometry

NASA Astrophysics Data System (ADS)

Marshall, Alan G.

1998-06-01

As for Fourier transform infrared (FT-IR) interferometry and nuclear magnetic resonance (NMR) spectroscopy, the introduction of pulsed Fourier transform techniques revolutionized ion cyclotron resonance mass spectrometry: increased speed (factor of 10,000), increased sensitivity (factor of 100), increased mass resolution (factor of 10,000-an improvement not shared by the introduction of FT techniques to IR or NMR spectroscopy), increased mass range (factor of 500), and automated operation. FT-ICR mass spectrometry is the most versatile technique for unscrambling and quantifying ion-molecule reaction kinetics and equilibria in the absence of solvent (i.e., the gas phase). In addition, FT-ICR MS has the following analytically important features: speed (~1 second per spectrum); ultrahigh mass resolution and ultrahigh mass accuracy for analysis of mixtures and polymers; attomole sensitivity; MSn with one spectrometer, including two-dimensional FT/FT-ICR/MS; positive and/or negative ions; multiple ion sources (especially MALDI and electrospray); biomolecular molecular weight and sequencing; LC/MS; and single-molecule detection up to 108 Dalton. Here, some basic features and recent developments of FT-ICR mass spectrometry are reviewed, with applications ranging from crude oil to molecular biology.

Elucidation of solution state complexation in wet-granulated oven-dried ibuprofen and beta-cyclodextrin: FT-IR and 1H-NMR studies.

PubMed

Ghorab, M K; Adeyeye, M C

2001-08-01

The effect of oven-dried wet granulation on the complexation of beta-cyclodextrin with ibuprofen (IBU) in solution was investigated using Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1H NMR), and molecular modeling. Granulation was carried out using 5 mL of three different granulating solvents; water, ethanol (95% v/v), and isopropanol and the granules were oven-dried at 60 degrees C for 2 h. The granules were compared to oven-dried physical mixture and conventionally prepared complex. Phase solubility study was performed to investigate the stability of the granulation-formed complexes in solution. FT-IR was used to examine the complexation in the granules while 1H NMR, and molecular modeling studies were carried out to determine the mechanism of complexation in the water-prepared granules. The solubility studies suggested a 1:1 complex between IBU and betaCD. It also showed that the stability of the complex in solution was in the following order with respect to the granulating solvents: ethanol > water > isopropanol. The FT-IR study revealed a shift in the carboxylic acid stretching band and decrease in the intensities of the C-H bending bands of the isopropyl group and the out-of-plane aromatic ring, of IBU, in granules compared to the oven-dried physical mixture. This indicated that granules might have some extent of solid state complexation that could further enhance dissolution and the IBU-betaCD solution state complexation. 1H NMR showed that water prepared oven-dried granules had a different 1H NMR spectrum compared to similarly made oven-dried physical mixture, indicative of complexation in the former. The 1H NMR and the molecular modeling studies together revealed that solution state complexation from the granules occurred by inclusion of the isopropyl group together with part of the aromatic ring of IBU into the betaCD cavity probably through its wider side. These results indicate that granulation process induced faster complexation in solution which enhances the solubility and the dissolution rate of poorly soluble drugs. The extent of complexation in the granules was dependent on the type of solvent used.

Interpreting the results of chemical stone analysis in the era of modern stone analysis techniques

PubMed Central

Gilad, Ron; Williams, James C.; Usman, Kalba D.; Holland, Ronen; Golan, Shay; Ruth, Tor; Lifshitz, David

2017-01-01

Introduction and Objective Stone analysis should be performed in all first-time stone formers. The preferred analytical procedures are Fourier-transform infrared spectroscopy (FT-IR) or X-ray diffraction (XRD). However, due to limited resources, chemical analysis (CA) is still in use throughout the world. The aim of the study was to compare FT-IR and CA in well matched stone specimens and characterize the pros and cons of CA. Methods In a prospective bi-center study, urinary stones were retrieved from 60 consecutive endoscopic procedures. In order to assure that identical stone samples were sent for analyses, the samples were analyzed initially by micro-computed tomography to assess uniformity of each specimen before submitted for FTIR and CA. Results Overall, the results of CA did not match with the FTIR results in 56% of the cases. In 16% of the cases CA missed the major stone component and in 40% the minor stone component. 37 of the 60 specimens contained CaOx as major component by FTIR, and CA reported major CaOx in 47/60, resulting in high sensitivity, but very poor specificity. CA was relatively accurate for UA and cystine. CA missed struvite and calcium phosphate as a major component in all cases. In mixed stones the sensitivity of CA for the minor component was poor, generally less than 50%. Conclusions Urinary stone analysis using CA provides only limited data that should be interpreted carefully. Urinary stone analysis using CA is likely to result in clinically significant errors in its assessment of stone composition. Although the monetary costs of CA are relatively modest, this method does not provide the level of analytical specificity required for proper management of patients with metabolic stones. PMID:26956131

Comparison of FTIR-ATR and Raman spectroscopy in determination of VLDL triglycerides in blood serum with PLS regression

NASA Astrophysics Data System (ADS)

Oleszko, Adam; Hartwich, Jadwiga; Wójtowicz, Anna; Gąsior-Głogowska, Marlena; Huras, Hubert; Komorowska, Małgorzata

2017-08-01

Hypertriglyceridemia, related with triglyceride (TG) in plasma above 1.7 mmol/L is one of the cardiovascular risk factors. Very low density lipoproteins (VLDL) are the main TG carriers. Despite being time consuming, demanding well-qualified staff and expensive instrumentation, ultracentrifugation technique still remains the gold standard for the VLDL isolation. Therefore faster and simpler method of VLDL-TG determination is needed. Vibrational spectroscopy, including FT-IR and Raman, is widely used technique in lipid and protein research. The aim of this study was assessment of Raman and FT-IR spectroscopy in determination of VLDL-TG directly in serum with the isolation step omitted. TG concentration in serum and in ultracentrifugated VLDL fractions from 32 patients were measured with reference colorimetric method. FT-IR and Raman spectra of VLDL and serum samples were acquired. Partial least square (PLS) regression was used for calibration and leave-one-out cross validation. Our results confirmed possibility of reagent-free determination of VLDL-TG directly in serum with both Raman and FT-IR spectroscopy. Quantitative VLDL testing by FT-IR and/or Raman spectroscopy applied directly to maternal serum seems to be promising screening test to identify women with increased risk of adverse pregnancy outcomes and patient friendly method of choice based on ease of performance, accuracy and efficiency.

Studies of interaction of emodin and DNA in the presence of ethidium bromide by spectroscopic method

NASA Astrophysics Data System (ADS)

Bi, Shuyun; Zhang, Hanqi; Qiao, Chunyu; Sun, Ying; Liu, Chunming

2008-01-01

Emodin interacting with deoxyribonucleic acid (DNA) has been studied by different spectroscopic techniques, such as fluorescence, ultraviolet and visible (UV-vis), and fourier transform infared (FT-IR) spectroscopies, using ethidium bromide (EB) as a fluorescence probe of DNA. The decrease in the fluorescence of DNA-EB system on addition of emodin shows that the fluorescence quenching of DNA-EB complex by emodin occurs. The binding constants of emodin with DNA in the presence of EB are 6.02 × 10 4, 9.20 × 10 4 and 1.17 × 10 5 L mol -1 at 20, 35 and 50 °C, respectively. FT-IR spectrum further suggests that both the phosphate groups and the bases of DNA react with emodin. The reaction of DNA with emodin in the presence of EB is affected by ionic strength and temperature. The values of melting temperature ( Tm) of DNA-EB complex and emodin-DNA-EB complexes were determined, respectively. From the experiment evidences, the major binding mode of emodin with DNA should be the groove binding.

Characterization of interaction between esculin and human serum albumin in membrane mimetic environments

NASA Astrophysics Data System (ADS)

Zhang, Yaheng; Li, Jiazhong; Dong, Lijun; Li, Ying; Chen, Xingguo

2008-10-01

In this study the interaction between esculin and human serum albumin (HSA) in AOT/isooctane/water microemulsions was studied for the first time using fluorescence quenching technique in combination with UV absorption spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, circular dichroism (CD) spectroscopy and dynamic light scattering (DLS) technique. Fluorescence data in ω o 20 microemulsions revealed the presence of the binding site of esculin on HSA and its binding constants at four different temperatures were obtained. The affinities in microemulsions are similar to that in buffer solution. The alterations of protein secondary structure in the microemulsions in the absence and presence of esculin compared with the free form of HSA in buffer were qualitatively and quantitatively analyzed by the evidence from CD and FT-IR spectroscopes. The displacement experiments confirmed that esculin could bind to the site I of HSA, which was in agreement with the result of the molecular modeling study. Furthermore, the DLS data suggested that HSA may locate at the interface of the microemulsion and esculin could interact with them.

Spectroscopic, calorimetric and structural analyses of the effects of hydrothermal treatment of rice beans and the extraction solvent on starch characteristics.

PubMed

González-Cruz, Leopoldo; Montañez-Soto, José Luis; Conde-Barajas, Eloy; Negrete-Rodríguez, María de la Luz Xochilt; Flores-Morales, Areli; Bernardino-Nicanor, Aurea

2018-02-01

The modification of the starches extracted from rice beans both with and without hydrothermal treatment was evaluated via scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and Fourier transform infrared (FT-IR) and Raman spectroscopy. SEM indicated that the starch granules of rice beans exhibit wide variation in granule shape, showing the greatest size and modification of the surface when extracted with ethanol. It was found that the extraction solvent had no significant effect on the onset (T o ) and peak (T p ) temperatures of the starch, whereas hydrothermal treatment of rice beans decreased the T o , T p and ΔH of the starch. The modification of FT-IR spectra showed that hydrothermal treatment of rice beans and the solvent used in the extraction of starch affected starch crystallinity, mainly when ethanol was used. Raman spectroscopy revealed that the smaller changes in the starch bonds were due to the solvent used for starch extraction but that hydrothermal treatment disturbed all bonds in the starch. Copyright © 2017 Elsevier B.V. All rights reserved.

Small plastic debris in sediments from the Central Adriatic Sea: Types, occurrence and distribution.

PubMed

Mistri, Michele; Infantini, Vanessa; Scoponi, Marco; Granata, Tommaso; Moruzzi, Letizia; Massara, Francesca; De Donati, Miriam; Munari, Cristina

2017-11-15

This is the first survey to investigate the occurrence and extent of microplastic contamination in sediments collected along a coast-open sea 140km-long transect in the Central Adriatic Sea. Plastic debris extracted from 64 samples of sediments were counted, weighted and identified by Fourier-transform infrared spectroscopy (FT-IR). Several types of plastic particles were observed in 100% of the stations. Plastic particles ranged from 1 to 30mm in length. The primary shape types by number were filaments (69.3%), followed by fragments (16.4%), and film (14.3%). Microplastics (1-5mm) accounted for 65.1% of debris, mesoplastics (5-20mm) made up 30.3% of total amount, while macro debris (>20mm) accounted for 4.6% of total plastics collected. Identification through FT-IR spectroscopy evidenced the presence of 6 polymer types: the majority of plastic debris were nylon, polyethylene and ethylene vinyl alcohol copolymer. Our data are a baseline for microplastic research in the Adriatic Sea. Copyright © 2017 Elsevier Ltd. All rights reserved.

A novel method for the elaboration of hydroxyapatite with high purity by sol-gel using the albumin and comparison with the classical methods

NASA Astrophysics Data System (ADS)

Mohammed, Eddya; Bouazza, Tbib; Khalil, El-Hami

2018-02-01

In this paper, we report the first synthesis of hydroxyapatite (Hap) by sol-gel using the albumin (egg white) compared with the four classical elaboration methods such as co-precipitation, solid state, and solid-liquid samples of hydroxyapatite. We use a reference sample of hydroxyapatite bought from Fluka Chemika company (Lot and Filling code 385330/1 14599). All samples are characterized by X-ray diffraction (XRD), Uv-visible spectroscopy (Uv-Vis), and Fourier transforms infrared spectroscopy (FT-IR). The XRD study showed the existence of a Hexagonal phase for all our samples prepared in our laboratory and an orthorhombic phase for the Fulka Chemika sample of Hap (Lot and Filling code 385330/1 14599). The study by Uv-visible spectroscopy was performed to determine and compare the optical gap and the disorder of each sample of Hap. The FT-IR spectroscopy demonstrated that all our Hap samples had a similar mode of vibration of the chemical bonds (OH-) and (PO4)3-.

Thermal, structural, functional, optical and magnetic studies of pure and Ba doped CdO nanoparticles.

PubMed

Sivakumar, S; Venkatesan, A; Soundhirarajan, P; Khatiwada, Chandra Prasad

2015-12-05

In this research, a chemical precipitation method was used to synthesize undoped and doped cadmium oxide nanoparticles and studied by TG-DTA, XRD, FT-IR, SEM, with EDX and antibacterial activities, respectively. The melting points, thermal stability and the kinetic parameters like entropy (ΔS), enthalpy (ΔH), Gibb's energy (ΔG), activation energy (E), frequency factor (A) were evaluated from TG-DTA measurements. X-ray diffraction analysis (XRD) brought out the information about the synthesized products exist in spherical in shape with cubic structure. The functional groups and band area of the samples were established by Fourier transform infrared (FT-IR) spectroscopy. The direct and indirect band gap energy of pure and doped samples were determined by UV-Vis-DRS. The surface morphological, elemental compositions and particles sizes were evaluated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Finally, antibacterial activities indicated the Gram-positive and Gram-negative bacteria are more active in transporter, dehydrogenize and periplasmic enzymatic activities of pure and doped samples. Copyright © 2015 Elsevier B.V. All rights reserved.

A new μ3-oxo-centered tri-nuclear carboxyl bridged iron (III) complex with thio-methyl groups in the periphery: Structural, spectroscopic and electrochemical studies

NASA Astrophysics Data System (ADS)

Lu, Maofeng; Chen, Tingting; Wang, Miao; Jiang, Guomin; Lu, Tianhong; Jiang, Guoqing; Du, Jiangyan

2014-02-01

A tri-nuclear iron (III) complex [Fe3(μ3-O)(O2CC6H4SCH3)6(Py)3]FeCl4 has been synthesized and characterized by X-ray crystallography, Surface enhanced Raman Scattering (SERS), Fourier Transform Infra Red (FT-IR), Ultraviolet-Visible (UV-Vis) spectroscopy and Thermogravimetric analysis (TGA)/Differential scanning calorimetry (DSC). The functionalized thio-methyl groups around the periphery of the complex 1 may provide binding sites to the surface of some specific materials, such as noble metals. The Ag sols and complex 1-Ag sol had been characterized by SERS and UV-Vis spectroscopy. The complex 1 were also self-assembled on gold electrode by AuS bond, exhibiting an irreversible process at E1/2 = 0.967 V (ΔE = 0.525 V). Meanwhile the Raman spectra were compared with FT-IR, and the results indicated that the strong Raman lines either correspond to weak Infrared absorptions or are absent in the Infrared spectra.

Study on the interaction of triadimenol with calf thymus DNA by multispectroscopic methods and molecular modeling

NASA Astrophysics Data System (ADS)

Zhang, Yepeng; Zhang, Guowen; Fu, Peng; Ma, Yadi; Zhou, Jia

2012-10-01

The binding mechanism of triadimenol (NOL) to calf thymus DNA (ctDNA) in physiological buffer (pH 7.4) was investigated by multispectroscopic methods including UV-vis absorption, fluorescence, circular dichroism (CD), Fourier transform infrared (FT-IR), and nuclear magnetic resonance (1H NMR) spectroscopy, coupled with viscosity measurements and atomic force microscopy (AFM) technique. The results suggested that NOL interacted with ctDNA by intercalation mode. CD and AFM assays showed that NOL can damage the base stacking of ctDNA and result in regional cleavage of the two DNA strands. FT-IR and 1H NMR spectra coupled with molecular docking revealed that a specific binding mainly exists between NOL and G-C base pairs of the ctDNA where two hydrogen bonds form. Moreover, the association constants of NOL with DNA at three different temperatures were determined to be in the 103 L mol-1 range. The calculated thermodynamic parameters suggested that the binding of NOL to ctDNA was driven mainly by hydrogen bond and van der Waals.

Green synthesis of silver nanoparticles using marine algae Caulerpa racemosa and their antibacterial activity against some human pathogens

NASA Astrophysics Data System (ADS)

Kathiraven, T.; Sundaramanickam, A.; Shanmugam, N.; Balasubramanian, T.

2015-04-01

We present the synthesis and antibacterial activity of silver nanoparticles using Caulerpa racemosa, a marine algae. Fresh C. racemosa was collected from the Gulf of Mannar, Southeast coast of India. The seaweed extract was used for the synthesis of AgNO3 at room temperature. UV-visible spectrometry study revealed surface plasmon resonance at 413 nm. The characterization of silver nanoparticle was carried out using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and transmission electron microscope (TEM). FT-IR measurements revealed the possible functional groups responsible for reduction and stabilization of the nanoparticles. X-ray diffraction analysis showed that the particles were crystalline in nature with face-centered cubic geometry.TEM micrograph has shown the formation of silver nanoparticles with the size in the range of 5-25 nm. The synthesized AgNPs have shown the best antibacterial activity against human pathogens such as Staphylococcus aureus and Proteus mirabilis. The above eco-friendly synthesis procedure of AgNPs could be easily scaled up in future for the industrial and therapeutic needs.

Effect of accelerated weathering on surface chemistry of modified wood

NASA Astrophysics Data System (ADS)

Temiz, Ali; Terziev, Nasko; Eikenes, Morten; Hafren, Jonas

2007-04-01

In this study, the effects of UV-light irradiation and water spray on colour and surface chemistry of scots pine sapwood samples were investigated. The specimens were treated with chromated copper arsenate (CCA), a metal-free propiconazol-based formulation, chitosan, furfuryl alcohol and linseed and tall oils. The weathering experiment was performed by cycles of 2 h UV-light irradiation followed by water spray for 18 min. The changes at the surface of the weathered samples were characterised by Fourier transform infrared spectroscopy (FT-IR); colour characterizations were performed by measuring CIELab parameters. The results show that all treatment methods except chitosan treatment provided lower colour changes than the control groups after 800 h exposure in weathering test cycle, but differences between chitosan and control were also small. The lowest colour changes were found on linseed oil (full cell process) and CCA treated wood. FT-IR results show that oil treatment (linseed and tall oil) decreased the intensities of a lignin specific peak (1500-1515 cm -1). Absorption band changes at 1630-1660 cm -1 were reduced by all treatments.

One-step synthesis and characterizations of cerium oxide nanoparticles in an ambient temperature via Co-precipitation method

NASA Astrophysics Data System (ADS)

Pujar, Malatesh S.; Hunagund, Shirajahammad M.; Desai, Vani R.; Patil, Shivaprasadgouda; Sidarai, Ashok H.

2018-04-01

We report the simple Co-precipitation method for the synthesis of Cerium oxide (CeO2) nanoparticles (NPs) in an ambient temperature. We have taken the Cerium (III) nitrate hexahydrate (Ce(NO3)3.6H2O) and Sodium hydroxide (NaOH) as the precursors. The obtained NPs were analyzed using the UV-Vis spectrophotometer, Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The obtained results signify that UV-Vis spectrum exhibited a well-defined absorption peak at 274 nm and the estimated energy gap (Eg) is 4.05 eV. The FT-IR analysis provides the supporting evidence for the presence of bonding of O-H, nitrates, alcohols and O-Ce-O vibrations. The XRD result reveals that the synthesized CeO2 NPs was crystallite with cubic phase structure and the estimated average crystallite size of CeO2 NPs using Scherer's and W-H method was significantly different due to their assumptions. Further, it is purposed to study their photocatalytic biological activities.

The effect of pH and triethanolamine on sulfisoxazole complexation with hydroxypropyl-beta-cyclodextrin.

PubMed

Gladys, Granero; Claudia, Garnero; Marcela, Longhi

2003-11-01

A novel complexation of sulfisoxazole with hydroxypropyl-beta-cyclodextrin (HP-beta-CD) was studied. Two systems were used: binary complexes prepared with HP-beta-CD and multicomponent system (HP-beta-CD and the basic compound triethanolamine (TEA)). Inclusion complex formation in aqueous solutions and in solid state were investigated by the solubility method, thermal analysis (differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA)), Fourier-transform infrared spectroscopy (FT-IR) and dissolution studies. The solid complexes of sulfisoxazole were prepared by freeze-drying the homogeneous concentrated aqueous solutions in molar ratios of sulfisoxazole:HP-beta-CD 1:1 and 1:2, and sulfisoxazole:TEA:HP-beta-CD 1:1:2. FT-IR and thermal analysis showed differences among sulfisoxazole:HP-beta-CD and sulfisoxazole:TEA:HP-beta-CD and their corresponding physical mixtures and individual components. The HP-beta-CD solubilization of sulfisoxazole could be improved by ionization of the drug molecule through pH adjustments. However, larger improvements of the HP-beta-CD solubilization are obtained when multicomponent systems are used, allowing to reduce the amount of CD necessary to prepare the target formulation.

Waterborne Superhydrophobic and Superoleophobic Coatings for the Protection of Marble and Sandstone

PubMed Central

Aslanidou, Dimitra; Lampakis, Dimitrios

2018-01-01

Silica nanoparticles were dispersed in an aqueous emulsion of alkoxy silanes and organic fluoropolymer. The dispersion was sprayed onto white marble and sandstone. The deposited composite coatings exhibited (i) superhydrophobicity and superoleophobicity, as evidenced by the high (>150°) static contact angles of water and oil drops as well as (ii) water and oil repellency according to the low (<7°) corresponding tilt contact angles. Apart from marble and sandstone, the coatings with extreme wetting properties were deposited onto concrete, silk, and paper, thus demonstrating the versatility of the method. The siloxane/fluoropolymer product was characterized using Fourier Transform Infrared Spectroscopy (FT-IR), Raman spectroscopy and Scanning Electron Microscopy equipped with an Energy Dispersive X-ray Spectrometer (SEM-EDX). Moreover, SEM and FT-IR were used to reveal the surface structures of the composite coatings and their transition from superhydrophobicity to superhydrophilicity which occurred after severe thermal treatment. The composite coatings slightly reduced the breathability of marble and sandstone and had practically no optical effect on the colour of the two stones. Moreover, the coatings offered good protection against water penetration by capillarity. PMID:29642652

Effect of Heat Treatment Temperature on Chemical Compositions of Extracted Hydroxyapatite from Bovine Bone Ash

NASA Astrophysics Data System (ADS)

Younesi, M.; Javadpour, S.; Bahrololoom, M. E.

2011-11-01

This article presents the effect of heat treating temperature on chemical composition of hydroxyapatite (HA) that was produced by burning bovine bone, and then heat treating the obtained bone ash at different temperatures in range of 600-1100 °C in air. Bone ash and the resulting white powder from heat treating were characterized by Fourier transformed infrared spectroscopy (FT-IR) and x-ray diffractometry (XRD). The FT-IR spectra confirmed that heat treating of bone ash at temperature of 800 °C removed the total of organic substances. x-ray diffraction analysis showed that the white powder was HA and HA was the only crystalline phase indicated in heat treating product. x-ray fluorescence analyses revealed that calcium and phosphorous were the main elements and magnesium and sodium were minor impurities of produced powder at 800 °C. The results of the energy dispersive x-ray analysis showed that Ca/P ratio in produced HA varies in range of 1.46-2.01. The resulting material was found to be thermally stable up to 1100 °C.

Highly crystalline zinc incorporated hydroxyapatite nanorods' synthesis, characterization, thermal, biocompatibility, and antibacterial study

NASA Astrophysics Data System (ADS)

Udhayakumar, Gayathri; Muthukumarasamy, N.; Velauthapillai, Dhayalan; Santhosh, Shanthi Bhupathi

2017-10-01

Highly crystalline zinc incorporated hydroxyapatite (Zn-HAp) nanorods have been synthesized using microwave irradiation method. To improve bioactivity and crystallinity of pure HAp, zinc was incorporated into it. As-synthesized samples were characterized by Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction, field-emission scanning electron microscopy (FESEM), energy dispersive X-ray analysis (EDAX), high-resolution transmission electron microscopy (HRTEM), and the thermal and crystallinity behavior of Zn-HAp nanoparticle were studied by thermogravimetry (TGA) and differential scanning calorimetry (DSC). Antibacterial activity of the as-synthesized nanorods was evaluated against two prokaryotic strains ( Escherichia coli and Staphylococcus aureus). The FT-IR studies show the presence of hydroxide and phosphate functional groups. HRTEM and FESEM images showed highly crystalline rod-shaped nanoparticles with the diameter of about 50-60 nm. EDAX revealed the presence of Ca, Zn, P, and O in the prepared samples. The crystallinity and thermal stability were further confirmed by TGA-DSC analysis. The biocompatibility evaluation results promoted that the Zn-HAp nanorods are biologically active apatites and potentially promising bone-substitute biomaterials for orthopaedic application.

Synthesis and optical properties of Mg-Al layered double hydroxides precursor powders

NASA Astrophysics Data System (ADS)

Lin, Chia-Hsuan; Chu, Hsueh-Liang; Hwang, Weng-Sing; Wang, Moo-Chin; Ko, Horng-Huey

2017-12-01

The synthesis and optical properties of Mg-Al layered double hydroxide (LDH) precursor powders were investigated using X-ray diffraction (XRD), Fourier transform-infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), selected area electron diffraction (SAED), high-resolution TEM (HRTEM), UV-transmission spectrometer, and fluorescence spectrophotometer. The FT-IR results show that the intense absorption at around 1363-1377 cm-1 can be assigned to the antisymmetric ν3 mode of interlayer carbonate anions because the LDH phase contains some CO32-. The XRD results show that all of the Mg-Al LDH precursor powders contain only a single phase of [Mg0.833Al0.167(OH)2](CO3)0.083.(H2O)0.75 but have broad and weak intensities of peaks. All of Mg-Al LDHs precursor powders before calcination have the same photoluminescence (PL) spectra. Moreover, these spectra were excited at λex = 235 nm, and the broad emission band was in the range 325-650 nm. In the range, there were relatively strong intensity at around 360, 407 and 510 nm, respectively.

Assessment of the Effects Exerted by Acid and Alkaline Solutions on Bone: Is Chemistry the Answer?

PubMed

Amadasi, Alberto; Camici, Arianna; Porta, Davide; Cucca, Lucia; Merli, Daniele; Milanese, Chiara; Profumo, Antonella; Rassifi, Nabila; Cattaneo, Cristina

2017-09-01

The treatment of corpses with extremely acid or basic liquids is sometimes performed in criminal contexts. A thorough characterization by chemical analysis may provide further help to macroscopic and microscopic analysis; 63 porcine bone samples were treated with solutions at different pH (1-14) for immersion periods up to 70 days, as well as in extremely acidic sulfuric acid solutions (9 M/18 M) and extremely basic sodium hydroxide. Inductively coupled optical emission spectrometry (ICP-OES)/plasma mass spectrometry (ICP-MS), Fourier transform infrared spectroscopy (FT-IR), energy dispersive X-ray analysis (EDX), X-ray powder diffraction (XRPD), and scanning electron microscopy (SEM) showed that only the sulfuric acid solution 18 M was able to completely dissolve the sample. In addition, chemical analysis allowed to recognize the contact between bone and substances. Hydrated calcium sulfate arose from extreme pH. The possibility of detecting the presence of human material within the residual solution was demonstrated, especially with FT-IR, ICP-OES, and EDX. © 2017 American Academy of Forensic Sciences.

Antimicrobial activity of biopolymeric thin films containing flavonoid natural compounds and silver nanoparticles fabricated by MAPLE: A comparative study

NASA Astrophysics Data System (ADS)

Cristescu, R.; Visan, A.; Socol, G.; Surdu, A. V.; Oprea, A. E.; Grumezescu, A. M.; Chifiriuc, M. C.; Boehm, R. D.; Yamaleyeva, D.; Taylor, M.; Narayan, R. J.; Chrisey, D. B.

2016-06-01

The purpose of this study was to investigate the interactions between microorganisms, including the planktonic and adherent organisms, and biopolymer (polyvinylpyrrolidone), flavonoid (quercetin dihydrate and resveratrol)-biopolymer, and silver nanoparticles-biopolymer composite thin films that were deposited using matrix assisted pulsed laser evaporation (MAPLE). A pulsed KrF* excimer laser source was used to deposit the aforementioned composite thin films, which were characterized using Fourier transform infrared spectroscopy (FT-IR), infrared microscopy (IRM), scanning electron microscopy (SEM), Grazing incidence X-ray diffraction (GIXRD) and atomic force microscopy (AFM). The antimicrobial activity of thin films was quantified using an adapted disk diffusion assay against Gram-positive and Gram-negative bacteria strains. FT-IR, AFM and SEM studies confirmed that MAPLE may be used to fabricate thin films with chemical properties corresponding to the input materials as well as surface properties that are appropriate for medical use. The silver nanoparticles and flavonoid-containing films exhibited an antimicrobial activity both against Gram-positive and Gram-negative bacterial strains demonstrating the potential use of these hybrid systems for the development of novel antimicrobial strategies.

Effects on structural, optical, and magnetic properties of pure and Sr-substituted MgFe2O4 nanoparticles at different calcination temperatures

NASA Astrophysics Data System (ADS)

Loganathan, A.; Kumar, K.

2016-06-01

In the present work, pure and Sr2+ ions substituted Mg ferrite nanoparticles (NPs) had been prepared by co-precipitation method and their structural, optical, and magnetic properties at different calcination temperatures were studied. On this purpose, thermo gravimetric and differential thermal analysis (TG-DTA), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy, UV-Visible diffused reflectance spectroscopy, impedance spectroscopy, and vibrating sample magnetometer were carried out. The exo- and endothermic processes of synthesized precursors were investigated by TG-DTA measurements. The structural properties of the obtained products were examined by XRD analysis and show that the synthesized NPs are in the cubic spinel structure. The existence of two bands around 578-583 and 430-436 cm-1 in FT-IR spectrum also confirmed the formation of spinel-structured ferrite NPs. The lattice constants and particle size are estimated using XRD data and found to be strongly dependent on calcination temperatures. The optical, electrical, and magnetic properties of ferrite compositions also investigated and found to be strongly dependant on calcination temperatures.

Application of physico-chemical typing methods for the epidemiological analysis of Salmonella enteritidis strains of phage type 25/17.

PubMed Central

Seltmann, G.; Voigt, W.; Beer, W.

1994-01-01

Eighty-nine Salmonella enteritidis phage type 25/17 strains isolated from a localized outbreak in the German state Nordrhein-Westfalen (outbreak NWI) could not be further differentiated by biochemotyping and plasmid pattern analysis. They were submitted to a complex typing system consisting of modern physico-chemical analytical procedures. In lipopolysaccharide pattern analysis the strains proved to be homogeneous. In multilocus enzyme electrophoresis, outer membrane and whole cell protein pattern (WCPP) analysis, and Fourier-transform infrared (FT-IR) spectroscopy (increasing extent of differentiation in the given order) strains deviating from each basal pattern were found. The extent of correspondence in these deviations was satisfactory. Forty-six strains of the same sero- and phage type, however, obtained from different outbreaks, were additionally typed. The results obtained with them indicate that the data of the first group were not restricted to strains from outbreak NWI, but of general validity. It was found that both WCPP and FT-IR represent valuable methods for the sub-grouping of bacteria. Images Fig. 1 Fig. 2 Fig. 3 PMID:7995351

Effect of swift heavy O7+ ion radiations on conductivity of lithium based polymer blend electrolyte

NASA Astrophysics Data System (ADS)

Joge, Prajakta; Kanchan, D. K.; Sharma, Poonam; Jayswal, Manish; Avasthi, D. K.

2014-07-01

In the present work, effect of swift heavy O7+ ion of 80 MeV of different fluences, on conductivity of [PVA(47.5)-PEO(47.5)-LiCF3SO3(5)]-EC(8) polymeric films has been investigated using ac impedance spectroscopy. The power law exponent n, hopping frequency ωh and activation energies for conduction Eac and relaxation Ear, have been investigated for different fluences. The DSC measurements are carried out in order to investigate the variations in the degree of crystallinity and thermal parameters (Tm) of the blend specimen prior and after irradiation. The Fourier Transform Infrared (FT-IR) measurements are carried out in order to investigate the changes in the vibrational modes of molecules upon irradiation. The FT-IR measurements corroborate the formation of amorphous phase in the blend matrix after irradiation. The conductivity is found to be optimum at the fluence of 1×1012 ions/cm2. The enhancement and the improvement in the electrolytic properties of PVA-PEO blend upon O7+ ion irradiation have been observed.

Nanofibers of cellulose bagasse from Agave tequilana Weber var. azul by electrospinning: preparation and characterization.

PubMed

Robles-García, Miguel Ángel; Del-Toro-Sánchez, Carmen Lizette; Márquez-Ríos, Enrique; Barrera-Rodríguez, Arturo; Aguilar, Jacobo; Aguilar, José A; Reynoso-Marín, Francisco Javier; Ceja, I; Dórame-Miranda, R; Rodríguez-Félix, Francisco

2018-07-15

In this study, cellulose of bagasse from Agave tequilana Weber var. azul was extracted to elaborate nanofibers by the electrospinning technique. Fiber characterization was performed using Transmission Electron Microscopy (TEM), x-ray, Fournier Transform-InfraRed (FT-IR) spectroscopy, and thermal analysis by Differential Scanning Calorimetry-Thermogravimetric Analysis (DSC-TGA). Different diameters (ranging from 54.57 ± 0.02 to 171 ± 0.01 nm) of nanofibers were obtained. Cellulose nanofibers were analyzed by means of x-ray diffraction, where we observed a total loss of crystallinity in comparison with the cellulose, while FT-IR spectroscopy revealed that the hemicellulose and lignin present in the agave bagasse were removed. Thermal analysis showed that nanofibers exhibit enhanced thermal properties, and the zeta potential value (-32.5 mV) demonstrated moderate stability in the sample. In conclusion, the nanofibers obtained provide other alternatives-of-use for this agro-industrial residue and could have potential in various industrial applications, among these encapsulation of bioactive compounds and reinforcing material, to mention a few. Copyright © 2018 Elsevier Ltd. All rights reserved.

Further characteristics of Arcanobacterium pinnipediorum DSM 28752T and Arcanobacterium wilhelmae DSM 102162T, two novel species of genus Arcanobacterium.

PubMed

Sammra, Osama; Rau, Jörg; Wickhorst, Jörn; Alssahen, Mazen; Hassan, Abdulwahed Ahmed; Lämmler, Christoph; Prenger-Berninghoff, Ellen; Abdulmawjood, Amir

2018-05-13

The newly described type strains Arcanobacterium pinnipediorum DSM 28752 T and Arcanobacterium wilhelmae DSM 102162 T , initially isolated from an anal swab of a harbor seal (Sammra et al. Int J Syst Evol Microbiol 65:4539-4543, 2015) and the genital tract of a rhinoceros (Sammra et al. Int J Syst Evol Microbiol 67:2093-2097, 2017), could be further characterized by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and Fourier transform infrared (FT-IR) spectroscopy and by sequencing the genomic targets 16S-23S rDNA intergenic spacer region (ISR) and the genes rpoB, gap, and tuf. The two strains investigated in the present study were isolated together with several other bacterial species indicating that the pathogenic importance of both species remained unclear. However, the detection of specific spectra by MALDI-TOF MS and by FT-IR spectroscopy and the presented genotypic approaches might help to identify A. pinnipediorum and A. wilhelmae in the future and might elucidate the role these two species play in infections of animals.

Synthesis and characterization of fluorapatite-titania (FAp-TiO 2) nanocomposite via mechanochemical process

NASA Astrophysics Data System (ADS)

Ebrahimi-Kahrizsangi, Reza; Nasiri-Tabrizi, Bahman; Chami, Akbar

2010-09-01

In this paper, synthesis of bionanocomposite of fluorapatite-titania (FAp-TiO 2) was studied by using one step mechanochemical process. Characterization of the products was accomplished by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques. Based on XRD patterns and FT-IR spectroscopy, correlation between the structural features of the nanostructured FAp-TiO 2 and the process conditions was discussed. Variations in crystallite size, lattice strain, and volume fraction of grain boundary were investigated during milling and the following heat treatment. Crystallization of the nanocomposite occurred after thermal treatment at 650 °C. Morphological features of powders were influenced by the milling time. The resulting FAp-20 wt.%TiO 2 nanocomposite powder exhibited an average particle size of 15 nm after 20 h of milling. The results show that the one step mechanosynthesis technique is an effective route to prepare FAp-based nanocomposites with excellent morphological and structural features.

Polyaniline-Cadmium Ferrite Nanostructured Composite for Room-Temperature Liquefied Petroleum Gas Sensing

NASA Astrophysics Data System (ADS)

Kotresh, S.; Ravikiran, Y. T.; Tiwari, S. K.; Vijaya Kumari, S. C.

2017-08-01

We introduce polyaniline-cadmium ferrite (PANI-CdFe2O4) nanostructured composite as a room-temperature-operable liquefied petroleum gas (LPG) sensor. The structure of PANI and the composite prepared by chemical polymerization was characterized by Fourier-transform infrared (FT-IR) spectroscopy, x-ray diffraction (XRD) analysis, and field-emission scanning electron microscopy. Comparative XRD and FT-IR analysis confirmed CdFe2O4 embedded in PANI matrix with mutual interfacial interaction. The nanostructure of the composite was confirmed by transmission electron microscopy. A simple LPG sensor operable at room temperature, exclusively based on spin-coated PANI-CdFe2O4 nanocomposite, was fabricated with maximum sensing response of 50.83% at 1000 ppm LPG. The response and recovery time of the sensor were 50 s and 110 s, respectively, and it was stable over a period of 1 month with slight degradation of 4%. The sensing mechanism is discussed on the basis of the p- n heterojunction barrier formed at the interface of PANI and CdFe2O4.

Synthesis and characterization of nano TiO2-SiO2: PVA composite - a novel route

NASA Astrophysics Data System (ADS)

Venckatesh, Rajendran; Balachandaran, Kartha; Sivaraj, Rajeshwari

2012-07-01

A novel, simple, less time consuming and cost-effective sol-gel method has been developed to synthesize nano titania-silica with polyvinyl alcohol (PVA) composite relatively at low temperature in acidic pH. Titania sol is prepared by hydrolysis of titanium tetrachloride and was mixed with silicic acid and tetrahydrofuran mixture. The reaction was carried out under vigorous stirring for 6 h and dried at room temperature with the addition of PVA solution. The resulting powders were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared (FT-IR), UV-visible spectroscopy and thermal techniques. The grain size of the particles was calculated by X-ray diffraction; surface morphology and chemical composition were determined from scanning electron microscopy-energy dispersive spectroscopy; metal oxide stretching was confirmed from FT-IR spectroscopy; bandgap was calculated using UV-visible spectroscopy, and thermal stability of the prepared composite was determined by thermogravimetric/differential thermal analysis. Since TiO2 got agglomerated on the surface of SiO2, effective absorptive sites increase which in turn increase the photocatalytic efficiency of the resulting composite.

FT-IR microscopic mappings of early mineralization in chick limb bud mesenchymal cell cultures

NASA Technical Reports Server (NTRS)

Boskey, A. L.; Camacho, N. P.; Mendelsohn, R.; Doty, S. B.; Binderman, I.

1992-01-01

Chick limb bud mesenchymal cells differentiate into chondrocytes and form a cartilaginous matrix in culture. In this study, the mineral formed in different areas within cultures supplemented with 4 mM inorganic phosphate, or 2.5, 5.0, and 10 mM beta-glycerophosphate (beta GP), was characterized by Fourier-transform infrared (FT-IR) microscopy. The relative mineral-to-matrix ratios, and distribution of crystal sizes at specific locations throughout the matrix were measured from day 14 to day 30. The only mineral phase detected was a poorly crystalline apatite. Cultures receiving 4 mM inorganic phosphate had smaller crystals which were less randomly distributed around the cartilage nodules than those in the beta GP-treated cultures. beta GP-induced mineral consisted of larger, more perfect apatite crystals. In cultures receiving 5 or 10 mM beta GP, the relative mineral-to-matrix ratios (calculated from the integrated intensities of the phosphate and amide I bands, respectively) were higher than in the cultures with 4 mM inorganic phosphate or in the in vivo calcified chick cartilage.

Vibrational spectra (FT-IR, Raman and MI-IR) of α- and β-alanine

NASA Astrophysics Data System (ADS)

Rosado, Mário Túlio S.; Duarte, Maria Leonor R. S.; Fausto, Rui

1997-06-01

The vibrational spectra of α- and β-alaine molecules in both their zwitterionic and neutral forms are studied by FT-IR, Raman and MI-IR spectroscopy. Together with results from theoretical SCF-MO ab initio calculations, the spectroscopic data obtained under the various experimental conditions used in this study (crystalline phase; low temperature matrix isolated molecules) enable to undertake a detailed assignment of the vibrational spectra of the studied compounds.

DFT, FT-IR, FT-Raman and vibrational studies of 3-methoxyphenyl boronic acid

NASA Astrophysics Data System (ADS)

Patil, N. R.; Hiremath, Sudhir M.; Hiremath, C. S.

2018-05-01

The aim of this work is to study the possible stable, geometrical molecular structure, experimental and theoretical FT-IR and FT-Raman spectroscopic methods of 3-Methoxyphenyl boronic acid (3MPBA). FT-IR and FT-Raman spectra were recorded in the region of 4000-400 cm-1 and 40000-50 cm-1 respectively. The optimized geometric structure and vibrational wavenumbers of the title compound were searched by B3LYP hybrid density functional theory method with 6-311++G (d, p) basis set. The Selectedexperimentalbandswereassignedandcharacterizedonthebasisofthescaledtheoreticalwavenumbersby their potential energy distribution (PED) of the vibrational modes obtained from VEDA 4 program. Finally, the predicted calculation results were applied to simulated FT-IR and FT-Raman spectra of the title compound, which show agreement with the observed spectra. Whereas, it is observed that, the theoretical frequencies are more than the experimental one for O-H stretching vibration modes of the title molecule.

Vibrational (FT-IR, Raman) and DFT analysis on the structure of labile drugs. The case of crystalline tebipenem and its ester

NASA Astrophysics Data System (ADS)

Paczkowska, Magdalena; Mizera, Mikołaj; Dzitko, Jakub; Lewandowska, Kornelia; Zalewski, Przemysław; Cielecka-Piontek, Judyta

2017-04-01

A tebipenem is active form of the first, oral carbapenem antibiotic - tebipenem pivoxyl. The optimized conformations of tebipenem pivoxyl and tebipenem were determinated by quantum-chemical calculations performed with the use of B3LYP functional and 6-31G(d,p) as a basis set. For the most stable conformations of tebipenem and its ester were established theoretical Raman and FT-IR spectra. The theoretical approach in significant part was support for identification of experimental Raman (400-4000 cm-1) and FT-IR (100-4000 cm-1) of tebipenem and tebipenem pivoxil. The geometric structure of molecules, HOMO and LUMO orbitals and molecular electrostatic potential were also determined. The benefits of applying FT-IR and Raman scattering spectroscopy for characterization of tebipenem and its ester consisted in demonstrating differences in their spectral properties.

FT-IR spectroscopy characterization of schwannoma: a case study

NASA Astrophysics Data System (ADS)

Ferreira, Isabelle; Neto, Lazaro P. M.; das Chagas, Maurilio José; Carvalho, Luís. Felipe C. S.; dos Santos, Laurita; Ribas, Marcelo; Loddi, Vinicius; Martin, Airton A.

2016-03-01

Schwannoma are rare benign neural neoplasia. The clinical diagnosis could be improved if novel optical techniques are performed. Among these techniques, FT-IR is one of the currently techniques which has been applied for samples discrimination using biochemical information with minimum sample preparation. In this work, we report a case of a schwannoma in the cervical region. A histological examination described a benign process. An immunohistochemically examination demonstrated positivity to anti-S100 protein antibody, indicating a diagnosis of schwannoma. The aim of this analysis was to characterize FT-IR spectrum of the neoplastic and normal tissue in the fingerprint (1000-1800 cm-1) and high wavenumber region (2800-3600 cm-1). The IR spectra were collect from tumor tissue and normal nerve samples by a FT-IR spectrophotometer (Spotlight Perkin Elmer 400, USA) with 64 scans, and resolution of 4 cm-1. A total of twenty spectra were recorded (10 from schwannoma and 10 from nerve). Multivariate Analysis was used to classify the data. Through average and standard deviation analysis we observed that the main spectral change occurs at ≍1600 cm-1 (amide I) and ≍1400 cm-1 (amide III) in the fingerprint region, and in CH2/CH3 protein-lipids and OH-water vibrations for the high wavenumber region. In conclusion, FT-IR could be used as a technique for schwannoma analysis helping to establish specific diagnostic.

Distinction of three wood species by Fourier transform infrared spectroscopy and two-dimensional correlation IR spectroscopy

NASA Astrophysics Data System (ADS)

Huang, Anmin; Zhou, Qun; Liu, Junliang; Fei, Benhua; Sun, Suqin

2008-07-01

Dalbergia odorifera T. Chen, Pterocarpus santalinus L.F. and Pterocarpus soyauxii are three kinds of the most valuable wood species, which are hard to distinguish. In this paper, differentiation of D. odorifera, P. santalinus and P. soyauxii was carried out by using Fourier transform infrared spectroscopy (FT-IR), second derivative IR spectra and two-dimensional correlation infrared (2D-IR) spectroscopy. The three woods have their characteristic peaks in conventional IR spectra. For example, D. odorifera has obvious absorption peaks at 1640 and 1612 cm -1; P. santalinus has only one peak at 1614 cm -1; and P. soyauxii has one peak at 1619 cm -1 and one shoulder peak at 1597 cm -1. To enhance spectrum resolution and amplify the differences between the IR spectra of different woods, the second derivative technology was adopted to examine the three wood samples. More differences could be observed in the region of 800-1700 cm -1. Then, the thermal perturbation is applied to distinguish different wood samples in an easier way, because of the spectral resolution being enhanced by the 2D correlation spectroscopy. In the region of 1300-1800 cm -1, D. odorifera has five auto-peaks at 1518, 1575, 1594, 1620 and 1667 cm -1; P. santalinus has four auto-peaks at 1469, 1518, 1627 and 1639 cm -1 and P. soyauxii has only two auto-peaks at 1627 and 1639 cm -1. It is proved that the 2D correlation IR spectroscopy can be a new method to distinguish D. odorifera, P. santalinus and P. soyauxii.

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

Sloan, J.M.; Pergantis, C.G.

Organic and organo-metallic coatings are presently being applied over bare copper as an approach to improve the co-planarity of circuit boards. Conformal organic solderability preservative coatings (OSP) are environmentally and economically advantageous over the more commonly used lead based coatings. Problems arise in assessing the solderability of the bare copper and the integrity of the organic coating. Specular reflectance Fourier transform infrared spectroscopy (FT-IR) was utilized to monitor and evaluate the formation of Cu oxides occurring on copper substrates used in the manufacturing of electronic circuit boards. Previous studies reported the utility of this technique. By measuring the oxide andmore » protective coating characteristics of these surfaces, their solderability performance can rapidly be evaluated in a manufacturing environment. OSP coated test specimens were subjected to hot-dry and hot-wet environmental conditions using MIL-STD-202F and MIL-STD-883E as guides. The resultant FT-IR spectra provided clear evidence for the formation of various Cu oxides at the Cu/OSP interface over exposure time, for the samples subjected to the hot-dry environment. IR spectral bands consistent with O-Cu-O and Cu{sub 2}O{sub 2} formation appear, while very minimal deterioration to the OSP coating was observed. The appearance of the Cu oxide layers grew steadily with increased environmental exposure. Specimens subjected to the hot-wet conditions showed no significant signs of deterioration. The IR data can be directly correlated to solderability performance as evaluated by wet balance testing.« less

Synthesis and characterization of some metal oxide nanocrystals by microwave irradiation

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

Rashad, M.; Gaber, A.; Abdelrahim, M. A.

2013-12-16

Copper oxide and cobalt oxide (CuO, Co3O4) nanocrystals (NCs) have been successfully prepared in a short time using microwave irradiation. The resulted powders of nanocrystals (NCs) were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Thermogravimetric analysis (TGA) measurements are also studied. Fourier-transform infrared (FT-IR) and UV–visible absorption spectroscopy of both kind of nanoparticels are illustrated. Optical absorption analysis indicated the direct band gap for both kinds of nanocrystals.

Properties of Unrelaxed InAs1-XSbX Alloys Grown on Compositionally Graded Buffers

DTIC Science & Technology

2011-10-07

beam epitaxy (MBE) as an alternative to HgCdTe for the fabrication of infrared (IR) photodetectors. These photodetector structures require the...FTIR) spectrometer equipped with a liquid-nitrogen cooled HgCdTe detector with a cut-off wavelength of 12 lm. The PL was excited by a 970 nm laser...characterized by surface roughness up to 10 nm for InAs0.56Sb0.44 samples. The PL and absorption spectra were measured with a Fourier-transform infrared

Sol-gel synthesis and characterization of SiO{sub 2}/PEG hybrid materials containing quercetin as implants with antioxidant properties

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

Catauro, Michelina; Bollino, Flavia; Gloria, Antonio

2016-05-18

In the present work, Silica/Polyethylene glycol (PEG) hybrid nanocomposites containing an antioxidant agent, the quercetin, were synthesized via sol-gel to be used as implants with antioxidant properties. Fourier transform infrared (FT-IR) analysis proved that a modification of both polymer and quercetin occurs due to synthesis process. Scanning electron microscope (SEM) showed that the proposed materials were hybrid nanocomposites. The bioactivity was ascertained by soaking the samples in a simulated body fluid (SBF).

Electrical conductivity and morphology of electrochemical synthesized polyaniline/CuO nano composites

NASA Astrophysics Data System (ADS)

Ashokkumar, S. P.; Yesappa, L.; Vijeth, H.; Niranjana, M.; Devendrappa, H.

2018-05-01

Polyaniline (PANI) and Polyaniline/CuO nanocomposite have been synthesized by using electrochemical deposition method. The composite was characterized using Fourier transform infra-red spectroscopy (FT-IR) to confirm the chemical interaction changes, micro structural morphology was done by Field Emission Scanning Electronic Microscopy (FESEM) and High Resolution Transmission Electron Microscopy (HRTEM). The dielectric constant and AC conductivity are found to increases with increase in temperature range (303 to 393K), these results shows enhancement in electrical conductivity due to effect of nanocomposite.

An automated baseline correction protocol for infrared spectra of atmospheric aerosols collected on polytetrafluoroethylene (Teflon) filters

NASA Astrophysics Data System (ADS)

Kuzmiakova, Adele; Dillner, Ann M.; Takahama, Satoshi

2016-06-01

A growing body of research on statistical applications for characterization of atmospheric aerosol Fourier transform infrared (FT-IR) samples collected on polytetrafluoroethylene (PTFE) filters (e.g., Russell et al., 2011; Ruthenburg et al., 2014) and a rising interest in analyzing FT-IR samples collected by air quality monitoring networks call for an automated PTFE baseline correction solution. The existing polynomial technique (Takahama et al., 2013) is not scalable to a project with a large number of aerosol samples because it contains many parameters and requires expert intervention. Therefore, the question of how to develop an automated method for baseline correcting hundreds to thousands of ambient aerosol spectra given the variability in both environmental mixture composition and PTFE baselines remains. This study approaches the question by detailing the statistical protocol, which allows for the precise definition of analyte and background subregions, applies nonparametric smoothing splines to reproduce sample-specific PTFE variations, and integrates performance metrics from atmospheric aerosol and blank samples alike in the smoothing parameter selection. Referencing 794 atmospheric aerosol samples from seven Interagency Monitoring of PROtected Visual Environment (IMPROVE) sites collected during 2011, we start by identifying key FT-IR signal characteristics, such as non-negative absorbance or analyte segment transformation, to capture sample-specific transitions between background and analyte. While referring to qualitative properties of PTFE background, the goal of smoothing splines interpolation is to learn the baseline structure in the background region to predict the baseline structure in the analyte region. We then validate the model by comparing smoothing splines baseline-corrected spectra with uncorrected and polynomial baseline (PB)-corrected equivalents via three statistical applications: (1) clustering analysis, (2) functional group quantification, and (3) thermal optical reflectance (TOR) organic carbon (OC) and elemental carbon (EC) predictions. The discrepancy rate for a four-cluster solution is 10 %. For all functional groups but carboxylic COH the discrepancy is ≤ 10 %. Performance metrics obtained from TOR OC and EC predictions (R2 ≥ 0.94 %, bias ≤ 0.01 µg m-3, and error ≤ 0.04 µg m-3) are on a par with those obtained from uncorrected and PB-corrected spectra. The proposed protocol leads to visually and analytically similar estimates as those generated by the polynomial method. More importantly, the automated solution allows us and future users to evaluate its analytical reproducibility while minimizing reducible user bias. We anticipate the protocol will enable FT-IR researchers and data analysts to quickly and reliably analyze a large amount of data and connect them to a variety of available statistical learning methods to be applied to analyte absorbances isolated in atmospheric aerosol samples.

Quantification of brain lipids by FTIR spectroscopy and partial least squares regression

NASA Astrophysics Data System (ADS)

Dreissig, Isabell; Machill, Susanne; Salzer, Reiner; Krafft, Christoph

2009-01-01

Brain tissue is characterized by high lipid content. Its content decreases and the lipid composition changes during transformation from normal brain tissue to tumors. Therefore, the analysis of brain lipids might complement the existing diagnostic tools to determine the tumor type and tumor grade. Objective of this work is to extract lipids from gray matter and white matter of porcine brain tissue, record infrared (IR) spectra of these extracts and develop a quantification model for the main lipids based on partial least squares (PLS) regression. IR spectra of the pure lipids cholesterol, cholesterol ester, phosphatidic acid, phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, sphingomyelin, galactocerebroside and sulfatide were used as references. Two lipid mixtures were prepared for training and validation of the quantification model. The composition of lipid extracts that were predicted by the PLS regression of IR spectra was compared with lipid quantification by thin layer chromatography.

Infrared Spectroscopy of Anhydrous Interplanetary Dust Particles

NASA Technical Reports Server (NTRS)

Keller, L. P.; Flynn, G. J.

2003-01-01

Infrared (IR) spectroscopy is the primary means of mineralogical analysis of materials outside our solar system. The identity and properties of circumstellar grains are inferred from spectral comparisons between astronomical observations and laboratory data from natural and synthetic materials. These comparisons have been facilitated by the Infrared Space Observatory (ISO), which obtained IR spectra from numerous astrophysical objects over a wide spectral range (out to 50/cm) where crystalline silicates and other phases have distinct features. The anhydrous interplanetary dust particles (IDPs) are particularly important comparison materials because some IDPs contain carbonaceous material with non-solar D/H and N-15/N-14 ratios and amorphous and crystalline silicates with non-solar 0- isotopic ratios, demonstrating that these IDPs contain preserved interstellar material. Here, we report on micro- Fourier transform (FT) IR spectrometry of IDPs, focusing on the inorganic components of primitive IDPs (FTIR spectra from the organic/carbonacecous materials in IDPs are described elsewhere).

Fourier transform infrared evanescent wave (FTIR-FEW) spectroscopy of tissue

NASA Astrophysics Data System (ADS)

Bruch, Reinhard F.; Sukuta, Sydney; Afanasyeva, Natalia I.; Kolyakov, Sergei F.; Butvina, Leonid N.

1997-05-01

A new Fourier transform infrared fiberoptic evanescent wave (FTIR-FEW) spectroscopy method has been developed for tissue diagnostics in the middle infrared (MIR) wavelength range (3 to 20 micrometers). Specific novel fiberoptical chemical and biological sensors have been studied and used for spectroscopic diagnostic purposes. These nontoxic and nonhygroscopic fiber sensors are characterized by (1) low optical losses (0.05 to 0.2 dB/m at about 10 micrometer) and (2) high flexibility. Our new fiber optical devices can be utilized with standard commercially available Fourier transform spectrometers including attenuated total reflection (ATR) techniques. They are in particular ideally suited for noninvasive, fast, direct, sensitive investigations of in vivo and ex vivo medical diagnostics applications. Here we present data on IR spectra of skin tissue in vivo for various cases of melanoma and nevus in the range of 1480 - 1800 cm-1. The interpretation of the spectra of healthy and different stages of tumor and cancer skin tissue clearly indicates that this technique can be used for precancer and cancer diagnostics. This technique can be designed for real-time and on-line computer modeling and analysis of tissue changes.

Discrimination of edible oils and fats by combination of multivariate pattern recognition and FT-IR spectroscopy: a comparative study between different modeling methods.

PubMed

Javidnia, Katayoun; Parish, Maryam; Karimi, Sadegh; Hemmateenejad, Bahram

2013-03-01

By using FT-IR spectroscopy, many researchers from different disciplines enrich the experimental complexity of their research for obtaining more precise information. Moreover chemometrics techniques have boosted the use of IR instruments. In the present study we aimed to emphasize on the power of FT-IR spectroscopy for discrimination between different oil samples (especially fat from vegetable oils). Also our data were used to compare the performance of different classification methods. FT-IR transmittance spectra of oil samples (Corn, Colona, Sunflower, Soya, Olive, and Butter) were measured in the wave-number interval of 450-4000 cm(-1). Classification analysis was performed utilizing PLS-DA, interval PLS-DA, extended canonical variate analysis (ECVA) and interval ECVA methods. The effect of data preprocessing by extended multiplicative signal correction was investigated. Whilst all employed method could distinguish butter from vegetable oils, iECVA resulted in the best performances for calibration and external test set with 100% sensitivity and specificity. Copyright © 2012 Elsevier B.V. All rights reserved.

Fast IR laser mapping ellipsometry for the study of functional organic thin films.

PubMed

Furchner, Andreas; Sun, Guoguang; Ketelsen, Helge; Rappich, Jörg; Hinrichs, Karsten

2015-03-21

Fast infrared mapping with sub-millimeter lateral resolution as well as time-resolved infrared studies of kinetic processes of functional organic thin films require a new generation of infrared ellipsometers. We present a novel laboratory-based infrared (IR) laser mapping ellipsometer, in which a laser is coupled to a variable-angle rotating analyzer ellipsometer. Compared to conventional Fourier-transform infrared (FT-IR) ellipsometers, the IR laser ellipsometer provides ten- to hundredfold shorter measurement times down to 80 ms per measured spot, as well as about tenfold increased lateral resolution of 120 μm, thus enabling mapping of small sample areas with thin-film sensitivity. The ellipsometer, equipped with a HeNe laser emitting at about 2949 cm(-1), was applied for the optical characterization of inhomogeneous poly(3-hexylthiophene) [P3HT] and poly(N-isopropylacrylamide) [PNIPAAm] organic thin films used for opto-electronics and bioapplications. With the constant development of tunable IR laser sources, laser-based infrared ellipsometry is a promising technique for fast in-depth mapping characterization of thin films and blends.

[Photodissociation of Acetylene and Acetone using Step-Scan Time-Resolved FTIR Emission Spectroscopy

NASA Technical Reports Server (NTRS)

McLaren, Ian A.; Wrobel, Jacek D.

1997-01-01

The photodissociation of acetylene and acetone was investigated as a function of added quenching gas pressures using step-scan time-resolved FTIR emission spectroscopy. Its main components consist of Bruker IFS88, step-scan Fourier Transform Infrared (FTIR) spectrometer coupled to a flow cell equipped with Welsh collection optics. Vibrationally excited C2H radicals were produced from the photodissociation of acetylene in the unfocused experiments. The infrared (IR) emission from these excited C2H radicals was investigated as a function of added argon pressure. Argon quenching rate constants for all C2H emission bands are of the order of 10(exp -13)cc/molecule.sec. Quenching of these radicals by acetylene is efficient, with a rate constant in the range of 10(exp -11) cc/molecule.sec. The relative intensity of the different C2H emission bands did not change with the increasing argon or acetylene pressure. However, the overall IR emission intensity decreased, for example, by more than 50% when the argon partial pressure was raised from 0.2 to 2 Torr at fixed precursor pressure of 160mTorr. These observations provide evidence for the formation of a metastable C2H2 species, which are collisionally quenched by argon or acetylene. Problems encountered in the course of the experimental work are also described.

Supercritical Fluid Chromatography/Fourier Transform Infrared Spectroscopy Of Food Components

NASA Astrophysics Data System (ADS)

Calvey, Elizabeth M.; Page, Samuel W.; Taylor, Larry T.

1989-12-01

Supercritical fluid (SF) technologies are being investigated extensively for applications in food processing. The number of SF-related patents issued testifies to the level of interest. Among the properties of materials at temperatures and pressures above their critical points (supercritical fluids) is density-dependent solvating power. Supercritical CO2 is of particular interest to the food industry because of its low critical temperature (31.3°C) and low toxicity. Many of the components in food matrices react or degrade at elevated temperatures and may be adversely affected by high temperature extractions. Likewise, these components may not be amenable to GC analyses. Our SF research has been in the development of methods employing supercritical fluid chromatography (SFC) and extraction (SFE) coupled to a Fourier transform infrared (FT-IR) spectrometer to investigate food composition. The effects of processing techniques on the isomeric fatty acid content of edible oils and the analysis of lipid oxidation products using SFC/FT-IR with a flow-cell interface are described.

Numerous applications of fiber optic evanescent wave Fourier transform infrared (FEW-FTIR) spectroscopy for subsurface structural analysis

NASA Astrophysics Data System (ADS)

Afanasyeva, Natalia I.; Welser, Leslie; Bruch, Reinhard F.; Kano, Angelique; Makhine, Volodymyr

1999-10-01

A new infrared (IR) interferometric method has been developed in conjunction with low-loss, flexible optical fibers, sensors, and probes. This combination of fiber optical sensors and Fourier Transform (FT) spectrometers can be applied to many fields, including (1) noninvasive medical diagnostics of cancer and other different diseases in vivo, (2) minimally invasive bulk diagnostics of tissue, (3) remote monitoring of tissue, chemical processes, and environment, (4) surface analysis of polymers and other materials, (5) characterization of the quality of food, pharmacological products, cosmetics, paper, and other wood-related products, as well as (6) agricultural, forensic, geological, mining, and archeological field measurements. In particular, our nondestructive, fast, compact, portable, remote and highly sensitive diagnostics tools are very promising for subsurface analysis at the molecular level without sample preparation. For example, this technique is ideal for different types of soft porous foams, rough polymers, and rock surfaces. Such surfaces, as well as living tissue, are very difficult to investigate by traditional FTIR methods. We present here FEW-FTIR spectra of polymers, banana and grapefruit peels, and living tissues detected directly at surfaces. In addition, results on the vibrational spectral analysis of normal and pathological skin tissue in the region of 850 - 4000 cm-1 are discussed.

Modification of fluorescence and optical properties of Rhodamine B dye doped PVA/Chitosan polymer blend films

NASA Astrophysics Data System (ADS)

Padmakumari, R.; Ravindrachary, V.; Mahantesha, B. K.; Sagar, Rohan N.; Sahanakumari, R.; Bhajantri, R. F.

2018-05-01

Pure and Rhodamine B doped Poly (vinyl alcohol)/Chitosan composite films are prepared using solution casting method. Fourier transforms infrared spectra (FTIR), Ultraviolet-Visible (UV-Vis), fluorescence studies were used to characterize the prepared polymer films. The FT-IR results show that the appearance of new peaks along with shift in peak positions indicates the interaction of Rhodamine B with PVA-CS blend. Optical absorption edge, band gap and activation energy were determined from UV-Visible studies. The optical absorption edge increases, band gap decreases and activation energy increases with dopant concentration respectively. The corresponding emission spectra were studied using fluorescence spectroscopy. From the fluorescence study the quenching phenomena are observed in emission wavelength range of 607nm-613nm upon excitation with absorption maxima 443nm.

Photoacoustic Fourier Transform Infrared (FTIR) Spectroscopy Of Solids

NASA Astrophysics Data System (ADS)

Vidrine, D. Warren

1981-10-01

After discovering the photoacoustic effect, Alexander Graham Bell predicted its use in spectrometers, and that it would find its greatest utility "in the ultra-red." More than ninety years were required to fulfil his first prediction, and the second is still a prophecy. There is no record whether he ever imagined that an invention being developed that same winter by a young protege of his named Albert Michelson would ever be combined with his photoacoustic effect. A century later, the combination was made by Farrow Burnham, and Eyring, using a visible-range interferometer spectrometer of their own design. Soon afterwards, Rockley and myself, working independently, applied the technique to infrared measurements of solid samples. Photoacoustic cells are now commercially available as FT-IR accessories, and the technique is in use in the field.

Fabrication and characterization of nickel oxide nanoparticles/silicon NiO NPS/Si

NASA Astrophysics Data System (ADS)

Shuihab, Aliyah; Khalf, Surour

2018-05-01

In this study, (NiO) thin film which prepared by chemical method and deposited by drop casting technique on glass. The structural, optical and chemical analyses have been investigated. X-ray diffraction (XRD) measurements relieve that the (NiO) thin film was polycrystalline, cubic structure and there is no trace of the other material. UV-Vis measurements reveal that the energy gap of (NiO) thin film was found 1.8 eV. The Fourier Transform Infrared Spectroscopy (FTIR) spectrum of (NiO) thin film shows NiO nanoparticles had its IR peak of Ni-O stretching vibration and shifted to blue direction. Due to their quantum size effect and spherical nanostructures, the FTIR absorption of NiO nanoparticles is blue-shifted compared to that of the bulk form.

Synthesis and Characterization of Novel Fluorine-Containing Water-Based Antirust Coating

NASA Astrophysics Data System (ADS)

Wang, Huiru; Wang, Xin; Zhao, Xiongyan

2018-01-01

A fluorine-containing polyacrylate copolymer emulsion was synthesized by a seed emulsion polymerization method, in which styrene(St) and butyl acrylate (BA) were used as main monomers and dodecafluoroheptyl methacrylate(DFMA) as fluorine-containing monomer. The structure and properties were characterized by Fourier transform infrared spectrum (FT-IR), scanning electron microscopy (SEM), particle size analysis, differential scanning calorimetry (DSC). The FTIR results showed that DFMA was effectively involved in the emulsion copolymerization, and the formed emulsion particles had a narrow particle size distribution. From the results salt spray test presented, it seems when the content of DFMA was 5wt% anti-rust performance of emulsion is relatively better. DSC and TGA also showed that their film exhibited higher thermal stability than that of fluorine-free emulsion.

Crystalline structure analysis of cellulose treated with sodium hydroxide and carbon dioxide by means of X-ray diffraction and FTIR spectroscopy.

PubMed

Oh, Sang Youn; Yoo, Dong Il; Shin, Younsook; Kim, Hwan Chul; Kim, Hak Yong; Chung, Yong Sik; Park, Won Ho; Youk, Ji Ho

2005-10-31

Crystalline structures of cellulose (named as Cell 1), NaOH-treated cellulose (Cell 2), and subsequent CO2-treated cellulose (Cell 2-C) were analyzed by wide-angle X-ray diffraction and FTIR spectroscopy. Transformation from cellulose I to cellulose II was observed by X-ray diffraction for Cell 2 treated with 15-20 wt% NaOH. Subsequent treatment with CO2 also transformed the Cell 2-C treated with 5-10 wt% NaOH. Many of the FTIR bands including 2901, 1431, 1282, 1236, 1202, 1165, 1032, and 897 cm(-1) were shifted to higher wave number (by 2-13 cm(-1)). However, the bands at 3352, 1373, and 983 cm(-1) were shifted to lower wave number (by 3-95 cm(-1)). In contrast to the bands at 1337, 1114, and 1058 cm(-1), the absorbances measured at 1263, 993, 897, and 668 cm(-1) were increased. The FTIR spectra of hydrogen-bonded OH stretching vibrations at around 3352 cm(-1) were resolved into three bands for cellulose I and four bands for cellulose II, assuming that all the vibration modes follow Gaussian distribution. The bands of 1 (3518 cm(-1)), 2 (3349 cm(-1)), and 3 (3195 cm(-1)) were related to the sum of valence vibration of an H-bonded OH group and an intramolecular hydrogen bond of 2-OH ...O-6, intramolecular hydrogen bond of 3-OH...O-5 and the intermolecular hydrogen bond of 6-O...HO-3', respectively. Compared with the bands of cellulose I, a new band of 4 (3115 cm(-1)) related to intermolecular hydrogen bond of 2-OH...O-2' and/or intermolecular hydrogen bond of 6-OH...O-2' in cellulose II appeared. The crystallinity index (CI) was obtained by X-ray diffraction [CI(XD)] and FTIR spectroscopy [CI(IR)]. Including absorbance ratios such as A1431,1419/A897,894 and A1263/A1202,1200, the CI(IR) was evaluated by the absorbance ratios using all the characteristic absorbances of cellulose. The CI(XD) was calculated by the method of Jayme and Knolle. In addition, X-ray diffraction curves, with and without amorphous halo correction, were resolved into portions of cellulose I and cellulose II lattice. From the ratio of the peak area, that is, peak area of cellulose I (or cellulose II)/total peak area, CI(XD) were divided into CI(XD-CI) for cellulose I and CI(XD-CII) for cellulose II. The correlation between CI(XD-CI) (or CI(XD-CII)) and CI(IR) was evaluated, and the bands at 2901 (2802), 1373 (1376), 897 (894), 1263, 668 cm(-1) were good for the internal standard (or denominator) of CI(IR), which increased the correlation coefficient. Both fraction of the absorbances showing peak shift were assigned as the alternate components of CI(IR). The crystallite size was decreased to constant value for Cell 2 treated at >or= 15 wt% NaOH. The crystallite size of Cell 2-C (cellulose II) was smaller than that of Cell 2 (cellulose I) treated at 5-10 wt% NaOH. But the crystallite size of Cell 2-C (cellulose II) was larger than that of Cell 2 (cellulose II) treated at 15-20 wt% NaOH.

In vivo skin leptin modulation after 14 MeV neutron irradiation: a molecular and FT-IR spectroscopic study.

PubMed

Cestelli Guidi, M; Mirri, C; Fratini, E; Licursi, V; Negri, R; Marcelli, A; Amendola, R

2012-09-01

This paper discusses gene expression changes in the skin of mice treated by monoenergetic 14 MeV neutron irradiation and the possibility of monitoring the resultant lipid depletion (cross-validated by functional genomic analysis) as a marker of radiation exposure by high-resolution FT-IR (Fourier transform infrared) imaging spectroscopy. The irradiation was performed at the ENEA Frascati Neutron Generator (FNG), which is specifically dedicated to biological samples. FNG is a linear electrostatic accelerator that produces up to 1.0 × 10(11) 14-MeV neutrons per second via the D-T nuclear reaction. The functional genomic approach was applied to four animals for each experimental condition (unirradiated, 0.2 Gy irradiation, or 1 Gy irradiation) 6 hours or 24 hours after exposure. Coregulation of a subclass of keratin and keratin-associated protein genes that are physically clustered in the mouse genome and functionally related to skin and hair follicle proliferation and differentiation was observed. Most of these genes are transiently upregulated at 6 h after the delivery of the lower dose delivered, and drastically downregulated at 24 h after the delivery of the dose of 1 Gy. In contrast, the gene coding for the leptin protein was consistently upregulated upon irradiation with both doses. Leptin is a key protein that regulates lipid accumulation in tissues, and its absence provokes obesity. The tissue analysis was performed by monitoring the accumulation and the distribution of skin lipids using FT-IR imaging spectroscopy. The overall picture indicates the differential modulation of key genes during epidermis homeostasis that leads to the activation of a self-renewal process at low doses of irradiation.

Thermal and Chemical Characterization of Non-Metallic Materials Using Coupled Thermogravimetric Analysis and Infrared Spectroscopy

NASA Technical Reports Server (NTRS)

Huff, Timothy L.

2002-01-01

Thermogravimetric analysis (TGA) is widely employed in the thermal characterization of non-metallic materials, yielding valuable information on decomposition characteristics of a sample over a wide temperature range. However, a potential wealth of chemical information is lost during the process, with the evolving gases generated during thermal decomposition escaping through the exhaust line. Fourier Transform-Infrared spectroscopy (FT-IR) is a powerful analytical technique for determining many chemical constituents while in any material state, in this application, the gas phase. By linking these two techniques, evolving gases generated during the TGA process are directed into an appropriately equipped infrared spectrometer for chemical speciation. Consequently, both thermal decomposition and chemical characterization of a material may be obtained in a single sample run. In practice, a heated transfer line is employed to connect the two instruments while a purge gas stream directs the evolving gases into the FT-IR. The purge gas can be either high purity air or an inert gas such as nitrogen to allow oxidative and pyrolytic processes to be examined, respectively. The FT-IR data is collected realtime, allowing continuous monitoring of chemical compositional changes over the course of thermal decomposition. Using this coupled technique, an array of diverse materials has been examined, including composites, plastics, rubber, fiberglass epoxy resins, polycarbonates, silicones, lubricants and fluorocarbon materials. The benefit of combining these two methodologies is of particular importance in the aerospace community, where newly developing materials have little available data with which to refer. By providing both thermal and chemical data simultaneously, a more definitive and comprehensive characterization of the material is possible. Additionally, this procedure has been found to be a viable screening technique for certain materials, with the generated data useful in the selection of other appropriate analytical procedures for further material characterization.

Influence of high-energy milling on structure and microstructure of asbestos-cement materials

NASA Astrophysics Data System (ADS)

Iwaszko, Józef; Zawada, Anna; Lubas, Małgorzata

2018-03-01

Asbestos-Containing Waste (ACW) in the form of a fragment from an asbestos-cement board was subjected to high-energy milling in a planetary mill at a constant rotational speed of 650 rpm and for variable milling times: 1, 2, and 3 h. The initial and the milled materials were subjected to infrared spectroscopic examination to identify the asbestos variety and to evaluate changes in the structure caused by high-energy milling. FT-IR (Fourier Transform Infrared Spectroscopy) examinations followed optical microscopy and SEM (Scanning Electron Microscopy) studies as well as X-ray analysis of the phase composition. It was found that the asbestos fibres present in the asbestos-cement board were respirable fibres with pathogenic properties. Identifying asbestos using the spectroscopic method showed that chrysotile asbestos was present in the as-received ACW while no characteristics of absorption bands from crocidolite or amosite were found. The results of the spectroscopic examinations were confirmed by the X-ray phase analysis. During SEM investigations of the milled ACW, complete loss of the fibrous structure of chrysotile was observed. The FT-IR examinations of the milled material showed that with an increased milling time, the characteristic absorption bands characteristic for chrysotile diminished and already after 2 h of milling their almost complete decay was observed. Thereby, it was confirmed that high-energy milling results in destruction of the crystalline structure of the asbestos phase. The conducted studies have shown that the treatment of asbestos-cement materials using high-energy milling is an effective method for asbestos disposal, capable of competing with other technologies and solutions. Moreover, FT-IR spectroscopy was found to be useful to identify asbestos phases and to assess changes caused by high-energy milling.

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

Zhang Hui; Zou Kang; Guo Shaohuan

A nanostructural drug-inorganic clay composite involving a pharmaceutically active compound captopril (Cpl) intercalated Mg-Al-layered double hydroxides (Cpl-LDHs) with Mg/Al molar ratio of 2.06 has been assembled by coprecipitation method. Powder X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR) and Raman spectra analysis indicate a successful intercalation of Cpl between the layers with a vertical orientation of Cpl disulphide-containing S-S linkage. SEM photo indicates that as-synthesized Cpl-LDHs possess compact and non-porous structure with approximately and linked elliptical shape particles of ca. 50 nm. TG-DTA analyses suggest that the thermal stability of intercalated organic species is largely enhanced due to host-guest interactionmore » involving the hydrogen bond compared to pure form before intercalation. The in vitro release studies show that both the release rate and release percentages markedly decrease with increasing pH from 4.60 to 7.45 due to possible change of release mechanism during the release process. The kinetic simulation for the release data, and XRD and FT-IR analyses for samples recovered from release media indicate that the dissolution mechanism is mainly responsible for the release behaviour of Cpl-LDHs at pH 4.60, while the ion-exchange one is responsible for that at pH 7.45. - Graphical abstract: Based on XRD, FT-IR and Raman spectra analyses, it is suggested that captopril (Cpl) exists as its disulphide metabolites in the interlayer of Mg-Al-LDHs via hydrogen bonding between guest carboxylate function and hydroxyl group of the host layers. A schematic supramolecular structure of Cpl intercalates involving a vertical orientation of Cpl disulphide-containing S-S bond between the layers with carboxylate anions pointing to both hydroxide layers is presented.« less

H3PW12O40 Encapsulation by Nanoporous Metal Organic Framework HKUST-1: Synthesis, Characterization, Activity and Stability.

PubMed

Rafiee, Ezzat; Nobakht, Narges

2016-01-01

Hybrid composite material was obtained through encapsulation of H3PW12O40 (PW) into HKUST-1 (Cu3(BTC)2, BTC = 1,3,5-benzenetricarboxylic acid), in molar composition of 5 Cu(NO3)2 · 3H2O/2.8 BTC/0.3 PW/0.6 CTAB by adding solutions of PW and copper salts to mixture of BTC and surfactant. The catalyst was characterized by various techniques including powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), laser particle size analyzer, Brunauer Emmett-Teller (BET). The acidity of the catalyst was measured by a potentiometric titration with n-butylamine and PW/HKUST-1 presented very strong acidic sites with Ei > 100 mV. This nano catalyst was successfully used for the synthesis of various β-keto enol ethers at 45 °C with 51-98% yield after 5-75 min. The catalyst was easily recycled and reused at least four times without significant loss of its activity (94% yield after forth run). The presence of the PW in PW/HKUST-1 and reused PW/HKUST-1 structure, eliminating any doubt about collapse of the HKUST-1 after catalytic reaction and can be followed by FT-IR, XRD and SEM techniques. Brönsted and Lewis acidity of the PW/HKUST-1 catalyst was distinguished by studying the FT-IR and determined by chemisorption of pyridine. The strength and dispersion of the protons on PW/HKUST-1 was considerably high and active surface protons became more available for reactant.

Structural, spectral and birefringence studies of semiorganic nonlinear optical single crystal: Calcium5-sulfosalicylate

NASA Astrophysics Data System (ADS)

Shalini, D.; Kalainathan, S.; Ambika, V. Revathi; Hema, N.; Jayalakshmi, D.

2017-11-01

Semi-organic nonlinear optical crystal Calcium5-Sulfosalicylate (CA5SS) was grown by slow evaporation solution growth technique. The cell parameters and molecular structure of the grown crystal were studied by single crystal x-ray diffraction analysis. The presence of various functional groups of the grown crystal was confirmed using Fourier transform infrared (FT-IR), Fourier transform Raman (FT-Raman) analysis. UV-Visible spectrum shows that CA5SS crystals have high transmittance in the range of 330-900 nm. The refractive index, birefringence and transient photoluminescence properties of the grown crystal were analyzed. The frequency doubling of the grown crystal (CA5SS) were studied and compared with that of KDP.

Rapid habitability assessment of Mars samples by pyrolysis-FTIR

NASA Astrophysics Data System (ADS)

Gordon, Peter R.; Sephton, Mark A.

2016-02-01

Pyrolysis Fourier transform infrared spectroscopy (pyrolysis FTIR) is a potential sample selection method for Mars Sample Return missions. FTIR spectroscopy can be performed on solid and liquid samples but also on gases following preliminary thermal extraction, pyrolysis or gasification steps. The detection of hydrocarbon and non-hydrocarbon gases can reveal information on sample mineralogy and past habitability of the environment in which the sample was created. The absorption of IR radiation at specific wavenumbers by organic functional groups can indicate the presence and type of any organic matter present. Here we assess the utility of pyrolysis-FTIR to release water, carbon dioxide, sulfur dioxide and organic matter from Mars relevant materials to enable a rapid habitability assessment of target rocks for sample return. For our assessment a range of minerals were analyzed by attenuated total reflectance FTIR. Subsequently, the mineral samples were subjected to single step pyrolysis and multi step pyrolysis and the products characterised by gas phase FTIR. Data from both single step and multi step pyrolysis-FTIR provide the ability to identify minerals that reflect habitable environments through their water and carbon dioxide responses. Multi step pyrolysis-FTIR can be used to gain more detailed information on the sources of the liberated water and carbon dioxide owing to the characteristic decomposition temperatures of different mineral phases. Habitation can be suggested when pyrolysis-FTIR indicates the presence of organic matter within the sample. Pyrolysis-FTIR, therefore, represents an effective method to assess whether Mars Sample Return target rocks represent habitable conditions and potential records of habitation and can play an important role in sample triage operations.

Quantum chemical investigations on the molecular structure, FTIR, UV-Vis and HOMO-LUMO analysis of 15-16-epoxy-7b, 9a dihydroxylabdane 13(16), 14-dien-6-one

NASA Astrophysics Data System (ADS)

Uppal, Anshul; Pathania, Kamni; Khajuria, Yugal

2018-05-01

The structural, spectroscopic (Fourier Transform Infrared (FT-IR), Ultra-Violet Visible (UV-VIS)) and thermodynamic properties of 15, 16-epoxy-7b, 9a dihydroxylabdane-13(16), 14-dien-6-one were studied by using both experimental techniques and theoretical methods. The FTIR spectrum of the title compound was recorded in the spectral range 4000-400 cm-1. The UV-VIS spectrum was measured in the spectral range 190-800 nm. The quantum chemistry calculations have been performed to compute optimized geometry, molecular parameters, vibrational frequencies along with intensities using Hartree Fock (HF) theory and Density Functional Theory (DFT) with 6-31G basis set. The calculated HOMO-LUMO energies show that the charge transfer occurs within the molecule. The temperature dependence of the thermodynamic properties like heat capacity, entropy and enthalpy of the optimized structure were obtained. Finally, a comparison between the experimental data and the calculated results presented a good agreement.

Molecular orientation in aligned electrospun polyimide nanofibers by polarized FT-IR spectroscopy.

PubMed

Yang, Haoqi; Jiang, Shaohua; Fang, Hong; Hu, Xiaowu; Duan, Gaigai; Hou, Haoqing

2018-07-05

Quantitative explanation on the improved mechanical properties of aligned electrospun polyimide (PI) nanofibers as the increased imidization temperatures is highly required. In this work, polarized FT-IR spectroscopy is applied to solve this problem. Based on the polarized FT-IR spectroscopy and the molecular model in the fibers, the length of the repeat unit of PI molecule, the angle between the fiber axis and the symmetric stretching direction of carbonyl group on the imide ring, and the angle between the PI molecular axis and fiber axis are all investigated. The Mark-Howink equation is used to calculate the number-average molar mass of PI molecules. The orientation states of PI molecules in the electrospun nanofibers are studied from the number-average molar mass of PI molecules and the average fiber diameter. Quantitative analysis of the orientation factor of PI molecules in the electrospun nanofibers is performed by polarized FT-IR spectroscopy. Copyright © 2018 Elsevier B.V. All rights reserved.

Characterization of Meldrum's acid derivative 5-(5-Ethyl-1,3,4-thiadiazol-2-ylamino)methylene-2,2-dimethyl-1,3-dioxane-4,6-dione by Raman and FT-IR spectroscopy and DFT calculations

NASA Astrophysics Data System (ADS)

de Toledo, T. A.; da Silva, L. E.; Teixeira, A. M. R.; Freire, P. T. C.; Pizani, P. S.

2015-07-01

In this study, the structural and vibrational properties of Meldrum's acid derivative 5-(5-Ethyl-1,3,4-thiadiazol-2-ylamino)methylene-2,2-dimethyl-1,3-dioxane-4,6-dione, C11H13N3O4S were studied combining experimental techniques such as Raman and FT-IR spectroscopy and density functional theory (DFT) calculations. The Raman and FT-IR spectra were recorded at room conditions in the regions from 80 to 3400 cm-1 and 400 to 4000 cm-1, respectively. Vibrational wavenumbers were predicted using DFT calculations with the hybrid functional B3LYP and basis set 6-31G(d,p). A comparison between experimental and theoretical data is provided for the Raman and FT-IR spectra. The descriptions of the normal modes were carried by means of potential energy distribution (PED).

The characterization of natural gemstones using non-invasive FT-IR spectroscopy: New data on tourmalines.

PubMed

Mercurio, Mariano; Rossi, Manuela; Izzo, Francesco; Cappelletti, Piergiulio; Germinario, Chiara; Grifa, Celestino; Petrelli, Maurizio; Vergara, Alessandro; Langella, Alessio

2018-02-01

Fourteen samples of tourmaline from the Real Museo Mineralogico of Federico II University (Naples) have been characterized through multi-methodological investigations (EMPA-WDS, SEM-EDS, LA-ICP-MS, and FT-IR spectroscopy). The samples show different size, morphology and color, and are often associated with other minerals. Data on major and minor elements allowed to identify and classify tourmalines as follows: elbaites, tsilaisite, schorl, dravites, uvites and rossmanite. Non-invasive, non-destructive FT-IR and in-situ analyses were carried out on the same samples to validate this chemically-based identification and classification. The results of this research show that a complete characterization of this mineral species, usually time-consuming and expensive, can be successfully achieved through non-destructive FT-IR technique, thus representing a reliable tool for a fast classification extremely useful to plan further analytical strategies, as well as to support gemological appraisals. Copyright © 2017 Elsevier B.V. All rights reserved.

Rapid authentication and identification of different types of A. roxburghii by Tri-step FT-IR spectroscopy

NASA Astrophysics Data System (ADS)

Chen, Ying; Huang, Jinfang; Yeap, Zhao Qin; Zhang, Xue; Wu, Shuisheng; Ng, Chiew Hoong; Yam, Mun Fei

2018-06-01

Anoectochilus roxburghii (Wall.) Lindl. (Orchidaceae) is a precious traditional Chinese medicinal herb and has been perennially used to treat various illness. However, there were unethical sellers who adulterated wild A. roxburghii with tissue cultured and cultivated ones. Therefore, there is an urgent need for an effective authentication method to differentiate between these different types of A. roxburghii. In this research, the infrared spectroscopic tri-step identification approach including Fourier transform infrared spectroscopy (FT-IR), Second derivative infrared spectra (SD-IR) and two-dimensional correlation infrared spectra (2D-IR) was used to develop a simple and rapid method to discriminate between wild, cultivated and tissue cultivated A. roxburghii plant. Through this study, all three types of A. roxburghii plant were successfully identified and discriminated through the infrared spectroscopic tri-step identification method. Besides that, all the samples of wild, cultivated and tissue cultivated A. roxburghii plant were analysed with the Soft Independent Modelling of Class Analogy (SIMCA) pattern recognition technique to test and verify the experimental results. The results showed that the three types of A. roxburghii can be discriminated clearly as the recognition rate was 100% for all three types and the rejection rate was more than 60%. 70% of the validated samples were also identified correctly by the SIMCA model. The SIMCA model was also validated by comparing 70 standard herbs to the model. As a result, it was demonstrated that the macroscopic IR fingerprint method and the classification analysis could discriminate not only between the A. roxburghi samples and the standard herbs, it could also distinguish between the three different types of A. roxburghi plant in a direct, rapid and holistic manner.

Rapid authentication and identification of different types of A. roxburghii by Tri-step FT-IR spectroscopy.

PubMed

Chen, Ying; Huang, Jinfang; Yeap, Zhao Qin; Zhang, Xue; Wu, Shuisheng; Ng, Chiew Hoong; Yam, Mun Fei

2018-06-15

Anoectochilus roxburghii (Wall.) Lindl. (Orchidaceae) is a precious traditional Chinese medicinal herb and has been perennially used to treat various illness. However, there were unethical sellers who adulterated wild A. roxburghii with tissue cultured and cultivated ones. Therefore, there is an urgent need for an effective authentication method to differentiate between these different types of A. roxburghii. In this research, the infrared spectroscopic tri-step identification approach including Fourier transform infrared spectroscopy (FT-IR), Second derivative infrared spectra (SD-IR) and two-dimensional correlation infrared spectra (2D-IR) was used to develop a simple and rapid method to discriminate between wild, cultivated and tissue cultivated A. roxburghii plant. Through this study, all three types of A. roxburghii plant were successfully identified and discriminated through the infrared spectroscopic tri-step identification method. Besides that, all the samples of wild, cultivated and tissue cultivated A. roxburghii plant were analysed with the Soft Independent Modelling of Class Analogy (SIMCA) pattern recognition technique to test and verify the experimental results. The results showed that the three types of A. roxburghii can be discriminated clearly as the recognition rate was 100% for all three types and the rejection rate was more than 60%. 70% of the validated samples were also identified correctly by the SIMCA model. The SIMCA model was also validated by comparing 70 standard herbs to the model. As a result, it was demonstrated that the macroscopic IR fingerprint method and the classification analysis could discriminate not only between the A. roxburghi samples and the standard herbs, it could also distinguish between the three different types of A. roxburghi plant in a direct, rapid and holistic manner. Copyright © 2018 Elsevier B.V. All rights reserved.

Forensic Hair Differentiation Using Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Spectroscopy.

PubMed

Manheim, Jeremy; Doty, Kyle C; McLaughlin, Gregory; Lednev, Igor K

2016-07-01

Hair and fibers are common forms of trace evidence found at crime scenes. The current methodology of microscopic examination of potential hair evidence is absent of statistical measures of performance, and examiner results for identification can be subjective. Here, attenuated total reflection (ATR) Fourier transform-infrared (FT-IR) spectroscopy was used to analyze synthetic fibers and natural hairs of human, cat, and dog origin. Chemometric analysis was used to differentiate hair spectra from the three different species, and to predict unknown hairs to their proper species class, with a high degree of certainty. A species-specific partial least squares discriminant analysis (PLSDA) model was constructed to discriminate human hair from cat and dog hairs. This model was successful in distinguishing between the three classes and, more importantly, all human samples were correctly predicted as human. An external validation resulted in zero false positive and false negative assignments for the human class. From a forensic perspective, this technique would be complementary to microscopic hair examination, and in no way replace it. As such, this methodology is able to provide a statistical measure of confidence to the identification of a sample of human, cat, and dog hair, which was called for in the 2009 National Academy of Sciences report. More importantly, this approach is non-destructive, rapid, can provide reliable results, and requires no sample preparation, making it of ample importance to the field of forensic science. © The Author(s) 2016.

Discrimination and prediction of cultivation age and parts of Panax ginseng by Fourier-transform infrared spectroscopy combined with multivariate statistical analysis.

PubMed

Lee, Byeong-Ju; Kim, Hye-Youn; Lim, Sa Rang; Huang, Linfang; Choi, Hyung-Kyoon

2017-01-01

Panax ginseng C.A. Meyer is a herb used for medicinal purposes, and its discrimination according to cultivation age has been an important and practical issue. This study employed Fourier-transform infrared (FT-IR) spectroscopy with multivariate statistical analysis to obtain a prediction model for discriminating cultivation ages (5 and 6 years) and three different parts (rhizome, tap root, and lateral root) of P. ginseng. The optimal partial-least-squares regression (PLSR) models for discriminating ginseng samples were determined by selecting normalization methods, number of partial-least-squares (PLS) components, and variable influence on projection (VIP) cutoff values. The best prediction model for discriminating 5- and 6-year-old ginseng was developed using tap root, vector normalization applied after the second differentiation, one PLS component, and a VIP cutoff of 1.0 (based on the lowest root-mean-square error of prediction value). In addition, for discriminating among the three parts of P. ginseng, optimized PLSR models were established using data sets obtained from vector normalization, two PLS components, and VIP cutoff values of 1.5 (for 5-year-old ginseng) and 1.3 (for 6-year-old ginseng). To our knowledge, this is the first study to provide a novel strategy for rapidly discriminating the cultivation ages and parts of P. ginseng using FT-IR by selected normalization methods, number of PLS components, and VIP cutoff values.

Discrimination and prediction of cultivation age and parts of Panax ginseng by Fourier-transform infrared spectroscopy combined with multivariate statistical analysis

PubMed Central

Lim, Sa Rang; Huang, Linfang

2017-01-01

Panax ginseng C.A. Meyer is a herb used for medicinal purposes, and its discrimination according to cultivation age has been an important and practical issue. This study employed Fourier-transform infrared (FT-IR) spectroscopy with multivariate statistical analysis to obtain a prediction model for discriminating cultivation ages (5 and 6 years) and three different parts (rhizome, tap root, and lateral root) of P. ginseng. The optimal partial-least-squares regression (PLSR) models for discriminating ginseng samples were determined by selecting normalization methods, number of partial-least-squares (PLS) components, and variable influence on projection (VIP) cutoff values. The best prediction model for discriminating 5- and 6-year-old ginseng was developed using tap root, vector normalization applied after the second differentiation, one PLS component, and a VIP cutoff of 1.0 (based on the lowest root-mean-square error of prediction value). In addition, for discriminating among the three parts of P. ginseng, optimized PLSR models were established using data sets obtained from vector normalization, two PLS components, and VIP cutoff values of 1.5 (for 5-year-old ginseng) and 1.3 (for 6-year-old ginseng). To our knowledge, this is the first study to provide a novel strategy for rapidly discriminating the cultivation ages and parts of P. ginseng using FT-IR by selected normalization methods, number of PLS components, and VIP cutoff values. PMID:29049369

Control of composition and crystallinity in hydroxyapatite films deposited by electron cyclotron resonance plasma sputtering

NASA Astrophysics Data System (ADS)

Akazawa, Housei; Ueno, Yuko

2014-01-01

Hydroxyapatite (HAp) films were deposited by electron cyclotron resonance plasma sputtering under a simultaneous flow of H2O vapor gas. Crystallization during sputter-deposition at elevated temperatures and solid-phase crystallization of amorphous films were compared in terms of film properties. When HAp films were deposited with Ar sputtering gas at temperatures above 460 °C, CaO byproducts precipitated with HAp crystallites. Using Xe instead of Ar resolved the compositional problem, yielding a single HAp phase. Preferentially c-axis-oriented HAp films were obtained at substrate temperatures between 460 and 500 °C and H2O pressures higher than 1×10-2 Pa. The absorption signal of the asymmetric stretching mode of the PO43- unit (ν3) in the Fourier-transform infrared absorption (FT-IR) spectra was the narrowest for films as-crystallized during deposition with Xe, but widest for solid-phase crystallized films. While the symmetric stretching mode of PO43- (ν1) is theoretically IR-inactive, this signal emerged in the FT-IR spectra of solid-phase crystallized films, but was absent for as-crystallized films, indicating superior crystallinity for the latter. The Raman scattering signal corresponding to ν1 PO43- sensitively reflected this crystallinity. The surface hardness of as-crystallized films evaluated by a pencil hardness test was higher than that of solid-phase crystallized films.

Nanooxide/Polymer Composites with Silica@PDMS and Ceria-Zirconia-Silica@PDMS: Textural, Morphological, and Hydrophilic/Hydrophobic Features.

PubMed

Sulym, Iryna; Goncharuk, Olena; Sternik, Dariusz; Terpilowski, Konrad; Derylo-Marczewska, Anna; Borysenko, Mykola V; Gun'ko, Vladimir M

2017-12-01

SiO 2 @PDMS and CeO 2 -ZrO 2 -SiO 2 @PDMS nanocomposites were prepared and studied using nitrogen adsorption-desorption, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), measurements of advancing and receding contact angles with water, and microcalorimetry. The pore size distributions indicate that the textural characteristics change after oxide modification by poly(dimethylsiloxane) (PDMS). Composites are characterized by mainly mesoporosity and macroporosity of aggregates of oxide nanoparticles or oxide@PDMS nanoparticles and their agglomerates. The FT-IR spectra show that PDMS molecules cover well the oxide surface, since the intensity of the band of free silanols at 3748 cm -1 decreases with increasing PDMS concentration and it is absent in the IR spectrum at C PDMS  ≥ 20 wt% that occurs due to the hydrogen bonding of the PDMS molecules to the surface hydroxyls. SEM images reveal that the inter-particle voids are gradually filled and aggregates are re-arranged and increase from 20 to 200 nm in size with the increasing polymer concentration. The highest hydrophobicity (contact angle θ = 140° at C PDMS  = 20-40 wt%) is obtained for the CeO 2 -ZrO 2 -SiO 2 @PDMS nanocomposites. The heat of composite immersion in water shows a tendency to decrease with increasing PDMS concentration.

Evaluation of Fungal Deterioration in Liquidambar orientalis Mill. heartwood by FT-IR and light microscopy.

Treesearch

Nural Yilgor; Dilek Dogu; Roderquita Moore; Evren Terzi; S. Nami Kartal

2013-01-01

The chemical and morphological changes in heartwood specimens of Liquidambar orientalis Mill. caused by the white-rot fungus Trametes versicolor and the brown-rot fungi Tyromyces palustris and Gloeophyllum trabeum were studied by wet chemistry, FT-IR, GC-MS analyses, and photo-...

In-situ stressing of rock: Observation of infrared emission prior to failure

NASA Astrophysics Data System (ADS)

Dahlgren, R.; Freund, F. T.; Momayez, M.; Bleier, T. E.; Dunson, C.; Joggerst, P.; Jones, K.; Wang, S.

2009-12-01

Blocks of igneous rocks such as anorthosite and granite subjected at one end to uniaxial stress have been shown to emit a small but distinct excess amount of infrared (IR) light (Freund, F. T., et al, JASTP, 71, 2009). This anomalous IR emission arises from the radiative de-excitation of electron vacancy defects, which, upon stress-activation, flow into the unstressed portion and recombine at the surface. This non-thermal IR emission occurs in the 8 μm to 14 μm wavelength region. Field experiments are performed by slowly stressing large boulders and monitoring the IR emission in situ with a Bruker EM27 Fourier Transform Infrared (FTIR) spectrometer. The boulders are prepared by drilling four blind holes into the rock, 50-100 cm deep, in an array roughly parallel to, and behind, the surface from where the IR emission is monitored. Any debris and water is blown out of the boreholes with compressed air, and the rock is given time to dry and relax from drilling-induced stresses. The holes are then filled with grout that expands upon curing, creating an increasing radial pressure of up to 5 × 103 t/m2. The experiments were carried out with two large granite boulders, one of about 30 t of hard (over 150 MPa) granite at the University of Arizona’s Henry "Hank" Grunstedt San Xavier Mining Laboratory, located in the copper mining district near Tucson, AZ and the other of about 7 t of weathered granite in the Sierra Nevada foothills near Oakhurst, CA. The Bruker EM27 FTIR spectrometer equipped with a 20 cm reflective telescope collects the IR emission from a safe distance at a rate of a full 4-16 µm spectrum every 30 sec. After recording baseline data, the grout was mixed with water and poured into the holes as IR emission was monitored continuously until the experiment was terminated after rock failure. The time of failure is noted whenever the first acoustic or visual cues are sensed from the boulder. The IR data shows that after a period of quiescence, pronounced non-thermal IR emission is observed within minutes of the rock failure.

Verification of Ganoderma (lingzhi) commercial products by Fourier Transform infrared spectroscopy and two-dimensional IR correlation spectroscopy

NASA Astrophysics Data System (ADS)

Choong, Yew-Keong; Sun, Su-Qin; Zhou, Qun; Lan, Jin; Lee, Han-Lim; Chen, Xiang-Dong

2014-07-01

Ganoderma commercial products are typically based on two sources, raw material (powder form and/or spores) and extract (water and/or solvent). This study compared three types of Ganoderma commercial products using 1 Dimensional Fourier Transform infrared and second derivative spectroscopy. The analyzed spectra of Ganoderma raw material products were compared with spectra of cultivated Ganoderma raw material powder from different mushroom farms in Malaysia. The Ganoderma extract product was also compared with three types of cultivated Ganoderma extracts. Other medicinal Ganoderma contents in commercial extract product that included glucan and triterpenoid were analyzed by using FTIR and 2DIR. The results showed that water extract of cultivated Ganoderma possessed comparable spectra with that of Ganoderma product water extract. By comparing the content of Ganoderma commercial products using FTIR and 2DIR, product content profiles could be detected. In addition, the geographical origin of the Ganoderma products could be verified by comparing their spectra with Ganoderma products from known areas. This study demonstrated the possibility of developing verification tool to validate the purity of commercial medicinal herbal and mushroom products.

Long-term changes in the chemical composition of soil organic matter, depending on fertilization and crop rotation

NASA Astrophysics Data System (ADS)

Tammik, Kerttu; Kauer, Karin; Astover, Alar

2017-04-01

The objective of this study was to determine whether it is possible to assess the impact of different management practices (crop rotation, fertilization (organic and mineral fertilizers) on the chemical composition of soil organic matter, using Fourier transform infrared spectroscopy (FTIR). The study is based IOSDV long-term (established in 1989) three field crop rotation (potato-wheat-barely) experiment located in Tartu, Estonia. Soil samples (Stagnic Albeluvisol) were collected from the 0-20 cm depth in the autumn of 2015, air dried, sieved to 2 mm and grinded to obtain homogeneous samples. The content of soil organic matter was measured by the dry combustion method in a varioMax CNS elemental analyser (ELEMENTAR, Germany). The samples were analysed using Thermo-Nicolet iS10 Fourier Transform Infrared Spectrophotometer (FT-IR) and OMNIC software. An intense and sharp peak was recorded in the region of Si-O vibrations of clay minerals and polysaccharides in all samples analysed. The volume of the peak correlated with the quantity of fertilizers administered

Preparation of thermally stable nanocrystalline hydroxyapatite by hydrothermal method.

PubMed

Prakash Parthiban, S; Elayaraja, K; Girija, E K; Yokogawa, Y; Kesavamoorthy, R; Palanichamy, M; Asokan, K; Narayana Kalkura, S

2009-12-01

Thermally stable hydroxyapatite (HAp) was synthesized by hydrothermal method in the presence of malic acid. X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FT-IR), Raman spectroscopy, scanning electron microscopy (SEM), differential thermal analysis (DTA), thermogravimetric analysis (TGA) was done on the synthesized powders. These analyses confirmed the sample to be free from impurities and other phases of calcium phosphates, and were of rhombus morphology along with nanosized particles. IR and Raman analyses indicated the adsorption of malic acid on HAp. Thermal stability of the synthesized HAp was confirmed by DTA and TGA. The synthesized powders were thermally stable upto 1,400 degrees C and showed no phase change. The proposed method might be useful for producing thermally stable HAp which is a necessity for high temperature coating applications.

Micro-attenuated total reflection spectral imaging in archaeology: application to Maya paint and plaster wall decorations.

PubMed

Goodall, Rosemary A; Hall, Jay; Sharer, Robert J; Traxler, Loa; Rintoul, Llew; Fredericks, Peter M

2008-01-01

Fourier transform infrared (FT-IR) attenuated total reflection (ATR) imaging has been successfully used to identify individual mineral components of ancient Maya paint. The high spatial resolution of a micro FT-IR-ATR system in combination with a focal plane array detector has allowed individual particles in the paint to be resolved and identified from their spectra. This system has been used in combination with micro-Raman spectroscopy to characterize the paint, which was found to be a mixture of hematite and silicate particles with minor amounts of calcite, carbon, and magnetite particles in a sub-micrometer hematite and calcite matrix. The underlying stucco was also investigated and found to be a combination of calcite with fine carbon particles, making a dark sub-ground for the paint.

Self-standing paper based anodes prepared from siliconcarbonitride-MoS2 composite for Li-ion battery applications

NASA Astrophysics Data System (ADS)

David, Lamuel; Singh, Gurpreet

2013-03-01

We study synthesis of free-standing polymer derived SiCN/ MoS2 composite paper anode for Li-ion battery application. This was achieved following a two-step approach: First, polysilazane was interfaced with exfoliated MoS2 nanosheets which upon pyrolysis resulted in SiCN/MoS2 composite. Second, dispersion of SiCN/MoS2 in isopropanol was vacuum filtered resulting in formation of a self-standing composite paper. Physical and chemical characterization of the composite was carried out by use of electron microscopy, Fourier transform infrared spectroscopy (FT-IR) and Thermo-gravimetric analysis (TGA). FT-IR data indicated complete conversion of polysilazane precursor to SiCN ceramic, while electron microscopy confirmed layered structure of the paper. Thermo-gravimetric analysis showed enhanced thermodynamic stability of the composite paper up to 800 °C. Electrochemical analysis of SiCN/MoS2 composite paper anodes showed that Li-ion can reversible intercalate in the voltage range of 0-2.5 V with a first cycle discharge capacity of 770 mAh/g at a current density of 100 mA/g.

Characterization of Linum usitatissimum L. oil obtained from different extraction technique and in vitro antioxidant potential of supercritical fluid extract

PubMed Central

Chauhan, Rishika; Chester, Karishma; Khan, Yasmeen; Tamboli, Ennus Tajuddin; Ahmad, Sayeed

2015-01-01

Aim: Present investigation was aimed to characterize the fixed oil of Linum usitatissimum L. using five different extraction methods: Supercritical fluid extraction (SFE), ultrasound-assistance, soxhlet extraction, solvent extraction, and three phase partitioning method. Materials and Methods: The SFE conditions (temperature, pressure, and volume of CO2) were optimized prior for better yield. The extracted oils were analyzed and compared for their physiochemical parameters, high performance thin layer chromatography (HPTLC), gas chromatography-mass spectrometry (GC-MS), and Fourier-transformed infrared spectroscopy (FT-IR) fingerprinting. Antioxidant activity was also determined using 1,1-diphenyl-2-picrylhydrazyl and superoxide scavenging method. Result: The main fatty acids were α-linolenic acid, linoleic acid, palmitic acid, and stearic acid as obtained by GC-MS. HPTLC analysis revealed the presence of similar major components in chromatograms. Similarly, the pattern of peaks, as obtained in FT-IR and GC-MS spectra of same oils by different extraction methods, were superimposable. Conclusion: Analysis reported that the fixed oil of L. usitatissimum L. is a good source of n-3 fatty acid with the significant antioxidant activity of oil obtained from SFE extraction method. PMID:26681884

Characterization of modified PVDF membrane by gamma irradiation for non-potable water reuse.

PubMed

Lim, Seung Joo; Kim, Tak-Hyun; Shin, In Hwan

2015-01-01

Poly(vinylidene fluorine) (PVDF) membranes were grafted by gamma-ray irradiation and were sulfonated by sodium sulfite to modify the surface of the membranes. The characteristics of the modified PVDF membranes were evaluated by the data of Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscope (FE-SEM), the contact angle of the membrane surface and the water permeability. From the results of FT-IR, XPS and FE-SEM, it was shown that the modified membranes were successfully grafted by gamma-ray irradiation and were sulfonated. The content of oxygen and sulfur increased with the monomer concentration, while the content of fluorine sharply decreased. The pore size of the modified membranes decreased after gamma-ray irradiation. The contact angle and the water permeability showed that the hydrophilicity of the modified membranes played a role in determining the membrane performance. The feasibility study of the modified PVDF membranes for using non-potable water reuse were carried out using a laboratory-scale microfiltration system. Grey wastewater was used as the influent in the filtration unit, and permeate quality satisfied non-potable water reuse guidelines in the Republic of Korea.

Preparation and Characterization of Polyurethanes with Cross-Linked Siloxane in the Side Chain by Sol-Gel Reactions

PubMed Central

Zhao, Hui; Hao, Tong-Hui; Hu, Guo-Hua; Shi, Dean; Huang, Da; Jiang, Tao; Zhang, Qun-Chao

2017-01-01

A series of novel polyurethanes containing cross-linked siloxane in the side chain (SPU) were successfully synthesized through a sol-gel process. The SPU was composed of 0%–20% N-(n-butyl)-3-aminopropyltriethoxysilane (HDI-T) modified hexamethylene diisocynate homopolymer. The effects of HDI-T content on both the structure and properties of SPU were investigated by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), mechanical properties tests, gel content test, water contact angle measurement and water absorption test. FT-IR, XPS and XRD results confirmed the successful incorporation of HDI-T onto polyurethanes and the formation of Si–O–Si. The surface roughness and the Si content of SPU enhanced with the increase of HDI-T content. Both crystallization and melting temperature shifted to a lower point after the incorporation of HDI-T. The hydrophobicity, tensile strength, Young’s modulus and pencil hardness overall increased with the increasing of HDI-T content, whereas the thermal stability and the elongation at break of SPU slightly decreased. PMID:28772607

Optical, Structural, and Thermal Properties of Cerium-Doped Zinc Borophosphate Glasses.

PubMed

Choi, Su-Yeon; Ryu, Bong-Ki

2015-11-01

In this study, we verify the relationship between the optical properties and structure of cerium-doped zinc borophosphate glasses that have concurrence of non-bridging oxygen (NBO) and bridging oxygen (BO), Ce3+ and Ce4+, and BO3 structure and BO4 structure. We prepared cerium-doped zinc borophosphate glass with various compositions, given by xCeO2-(100-x)[50ZnO-10B2O3 -40P2O5] (x = 1 mol% to 6 mol%), and analyzed their optical band energy, glass transition temperature, crystallization temperature, density, and molar volume. Some of the techniques used for analysis were Fourier transform infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS). In the investigated glasses, the optical band gap energy decreased from 3.28 eV to 1.73 eV. From these results, we can deduce the changes when transitions occur from BO to NBO, from Ce3+ to Ce4+, and from the BO3 structure to the BO4 structure with increasing CeO2 content using FT-IR and XPS analysis. We also verified the changes in structural and physical properties from quantitative properties such as glass transition temperature, crystallization temperature, density, and molar volume.

A novel route for synthesis of nanocrystalline hydroxyapatite from eggshell waste.

PubMed

Siva Rama Krishna, D; Siddharthan, A; Seshadri, S K; Sampath Kumar, T S

2007-09-01

The eggshell waste has been value engineered to a nanocrystalline hydroxyapatite (HA) by microwave processing. To highlight the advantages of eggshell as calcium precursor in the synthesis of HA (OHA), synthetic calcium hydroxide was also used to form HA (SHA) following similar procedure and were compared with a commercially available pure HA (CHA). All the HAs were characterized by X-ray powder diffraction (XRD) method, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and specific surface area measurements. Nanocrystalline nature of OHA is revealed through characteristic broad peaks in XRD patterns, platelets of length 33-50 nm and width 8-14 nm in TEM micrograph and size calculations from specific surface area measurements. FT-IR spectra showed characteristic bands of HA and additionally peaks of carbonate ions. The cell parameter calculations suggest the formation of carbonated HA of B-type. The OHA exhibits superior sinterability in terms of hardness and density than both SHA and CHA may be due to larger surface area of its spherulite structure. The in vitro dissolution study shows longer stability in phosphate buffer and cell culture test using osteoblast cells establishes biocompatibility of OHA.

Revisiting the formation of cyclic clusters in liquid ethanol

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

Balanay, Mannix P.; Fan, Haiyan, E-mail: haiyan.fan@nu.edu.kz; Kim, Dong Hee

2016-04-21

The liquid phase of ethanol in pure and in non-polar solvents was studied at room temperature using Fourier transform infrared (FT-IR) and {sup 1}H nuclear magnetic resonance (NMR) spectroscopies together with theoretical approach. The FT-IR spectra for pure ethanol and solution in cyclohexane at different dilution stages are consistent with {sup 1}H NMR results. The results from both methods were best explained by the results of the density functional theory based on a multimeric model. It is suggested that cyclic trimers and tetramers are dominated in the solution of cyclohexane/hexane with the concentration greater than 0.5M at room temperature. Inmore » liquid ethanol, while the primary components at room temperature are cyclic trimers and tetramers, there is a certain amount (∼14%) of open hydroxide group representing the existence of chain like structures in the equilibria. The cyclic cluster model in the liquid and concentrated solution phase (>0.5M) can be used to explain the anomalously lower freezing point of ethanol (159 K) than that of water (273 K) at ambient conditions. In addition, {sup 1}H NMR at various dilution stages reveals the dynamics for the formation of cyclic clusters.« less

Spectroscopic analysis of irradiated erythrocytes

NASA Astrophysics Data System (ADS)

Selim, Nabila S.; Desouky, Omar S.; Ismail, Nagla M.; Dakrory, Amira Z.

2011-12-01

The aim of the present work is to study the effect of gamma radiation on the lipid part of the erythrocyte membrane, and to test the efficiency of lipoic acid as a radioprotector. This effect was evaluated using electron paramagnetic resonance (EPR), and Fourier transform infrared (FT-IR) spectroscopy. The results showed an increase in the number of spin density by 14%, 22% and 65% after exposure to 25, 50 and 100 Gy respectively; whereas there was a decline in the obtained density after incubation with lipoic acid by a factor of approximately 32%. The FT-IR spectra of the irradiated erythrocytes samples showed a marked decrease in the intensity of all characteristic peaks, which increased as the irradiation dose increased. The second-derivative of these spectra, allow the conformationally sensitive membrane acyl chain methylene stretching modes to be separated from the protein (mostly hemoglobin) vibrations that dominate the spectra of intact cells. The 2850 cm -1 band showed changes in the band shape and position after exposure to 50 and 100 Gy. Therefore it can be concluded that the band at 2850 cm -1 only is useful in monitoring the radiation effect of the lipids cell membrane intact cells.

Development of solid dispersions of artemisinin for transdermal delivery.

PubMed

Shahzad, Yasser; Sohail, Sadia; Arshad, Muhammad Sohail; Hussain, Talib; Shah, Syed Nisar Hussain

2013-11-30

Solid dispersions of the poorly soluble drug artemisinin were developed using polymer blends of polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG) with the aim of enhancing solubility and in vitro permeation of artemisinin through skin. Formulations were characterised using a combination of molecular dynamics (MD) simulations, differential scanning calorimetry (DSC), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). Solubility of artemisinin was determined in two solvents: de-ionised water and phosphate buffered saline (PBS; pH 7.4), while in vitro drug permeation studies were carried out using rabbit skin as a model membrane. MD simulations revealed miscibility between the drug and polymers. DSC confirmed the molecular dispersion of the drug in the polymer blend. Decrease in crystallinity of artemisinin with respect to polymer content and the absence of specific drug-polymer interactions were confirmed using XRD and FT-IR, respectively. The solubility of artemisinin was dramatically enhanced for the solid dispersions, as was the permeation of artemisinin from saturated solid-dispersion vehicles relative to that from saturated solutions of the pure drug. The study suggests that high energy solid forms of artemisinin could possibly enable transdermal delivery of artemisinin. Copyright © 2013 Elsevier B.V. All rights reserved.

Green synthesis of nitrogen-doped graphitic carbon sheets with use of Prunus persica for supercapacitor applications

NASA Astrophysics Data System (ADS)

Atchudan, Raji; Edison, Thomas Nesakumar Jebakumar Immanuel; Perumal, Suguna; Lee, Yong Rok

2017-01-01

Nitrogen-doped graphitic carbon sheets (N-GCSs) were prepared from the extract of unripe Prunus persica fruit by a direct hydrothermal method. The synthesized N-GCSs were examined by high resolution transmission electron microscopy (HRTEM), nitrogen adsorption-desorption isotherms, X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FT-IR) spectroscopy. HRTEM showed that the synthesized carbon sheets were graphitic with lattice fringes and an inter-layer distance of 0.36 nm. Doping with the nitrogen moiety present over the synthesized GCSs was confirmed by XPS, FT-IR spectroscopy, and energy dispersive X-ray spectroscopy elemental mapping. The fruit extract associated with hydrothermal-carbonization method is economical and eco-friendly with a single step process. The resulting carbon sheets could be modified and are promising candidates for nano-electronic applications, including supercapacitors. The synthesized N-GCSs-2 provided a high specific capacitance of 176 F g-1 at a current density of 0.1 A g-1. This electrode material has excellent cyclic stability, even after 2000 cycles of charge-discharge at a current density of 0.5 A g-1.

Lithium-ion battery electrolyte emissions analyzed by coupled thermogravimetric/Fourier-transform infrared spectroscopy

NASA Astrophysics Data System (ADS)

Bertilsson, Simon; Larsson, Fredrik; Furlani, Maurizio; Albinsson, Ingvar; Mellander, Bengt-Erik

2017-10-01

In the last few years the use of Li-ion batteries has increased rapidly, powering small as well as large applications, from electronic devices to power storage facilities. The Li-ion battery has, however, several safety issues regarding occasional overheating and subsequent thermal runaway. During such episodes, gas emissions from the electrolyte are of special concern because of their toxicity, flammability and the risk for gas explosion. In this work, the emissions from heated typical electrolyte components as well as from commonly used electrolytes are characterized using FT-IR spectroscopy and FT-IR coupled with thermogravimetric (TG) analysis, when heating up to 650 °C. The study includes the solvents EC, PC, DEC, DMC and EA in various single, binary and ternary mixtures with and without the LiPF6 salt, a commercially available electrolyte, (LP71), containing EC, DEC, DMC and LiPF6 as well as extracted electrolyte from a commercial 6.8 Ah Li-ion cell. Upon thermal heating, emissions of organic compounds and of the toxic decomposition products hydrogen fluoride (HF) and phosphoryl fluoride (POF3) were detected. The electrolyte and its components have also been extensively analyzed by means of infrared spectroscopy for identification purposes.

Dissolution enhancement of tadalafil by liquisolid technique.

PubMed

Lu, Mei; Xing, Haonan; Yang, Tianzhi; Yu, Jiankun; Yang, Zhen; Sun, Yanping; Ding, Pingtian

2017-02-01

This study aimed to enhance the dissolution of tadalafil, a poorly water-soluble drug by applying liquisolid technique. The effects of two critical formulation variables, namely drug concentration (17.5% and 35%, w/w) and excipients ratio (10, 15 and 20) on dissolution rates were investigated. Pre-compression tests, including particle size distribution, flowability determination, Fourier transform infrared (FT-IR), differential scanning calorimetry (DSC), X-ray diffractometry (XRD) and scanning electron microscopy (SEM), were carried out to investigate the mechanism of dissolution enhancement. Tadalafil liquisolid tablets were prepared and their quality control tests, dissolution study, contact angle measurement, Raman mapping, and storage stability test were performed. The results suggested that all the liquisolid tablets exhibited significantly higher dissolution rates than the conventional tablets and pure tadalafil. FT-IR spectrum reflected no drug-excipient interactions. DSC and XRD studies indicated reduction in crystallinity of tadalafil, which was further confirmed by SEM and Raman mapping outcomes. The contact angle measurement demonstrated obvious increase in wetting property. Taken together, the reduction of particle size and crystallinity, and the improvement of wettability were the main mechanisms for the enhanced dissolution rate. No significant changes were observed in drug crystallinity and dissolution behavior after storage based on XRD, SEM and dissolution results.

Preparation and characterization of cross-linked poly (vinyl alcohol)-graphene oxide nanocomposites as an interlayer for Schottky barrier diodes

NASA Astrophysics Data System (ADS)

Badrinezhad, Lida; Bilkan, Çigdem; Azizian-Kalandaragh, Yashar; Nematollahzadeh, Ali; Orak, Ikram; Altindal, Şemsettin

2018-01-01

Cross-linked polyvinyl alcohol (PVA) graphene oxide (GO) nanocomposites were prepared by simple solution-mixing route and characterized by Raman, UV-visible and fourier transform infrared (FT-IR) spectroscopy analysis, X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The XRD pattern and SEM analysis showed significant changes in the nanocomposite structures, and the FT-IR spectroscopy results confirmed the chemical interaction between the GO filler and the PVA matrix. After these morphological characterizations, PVA-GO-based diodes were fabricated and their electrical properties were characterized using current-voltage (I-V) and impedance-voltage-frequency (Z-V-f) measurements at room temperature. Semilogarithmic I-V characteristics of diode showed a good rectifier behavior. The values of C and G/ω increased with decreasing frequency due to the surface/interface states (Nss) which depend on the relaxation time and the frequency of the signal. The voltage, dependent profiles of Nss and series resistance (Rs) were obtained from the methods of high-low frequency capacitance and Nicollian and Brews, respectively. The obtained values of Nss and Rs were attributed to the use of cross-linked PVA-GO interlayer at the Au/n-Si interface.

Producing Lignin-Based Polyols through Microwave-Assisted Liquefaction for Rigid Polyurethane Foam Production.

PubMed

Xue, Bai-Liang; Wen, Jia-Long; Sun, Run-Cang

2015-02-10

Lignin-based polyols were synthesized through microwave-assisted liquefaction under different microwave heating times (5-30 min). The liquefaction reactions were carried out using polyethylene glycol (PEG-400)/glycerol as liquefying solvents and 97 wt% sulfur acid as a catalyst at 140 °C. The polyols obtained were analyzed for their yield, composition and structural characteristics using gel permeation chromatography (GPC), Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectra. FT-IR and NMR spectra showed that the liquefying solvents reacted with the phenol hydroxyl groups of the lignin in the liquefied product. With increasing microwave heating time, the viscosity of polyols was slightly increased and their corresponding molecular weight ( M W ) was gradually reduced. The optimal condition at the microwave heating time (5 min) ensured a high liquefaction yield (97.47%) and polyol with a suitable hydroxyl number (8.628 mmol/g). Polyurethane (PU) foams were prepared by polyols and methylene diphenylene diisocyanate (MDI) using the one-shot method. With the isocyanate/hydroxyl group ([NCO]/[OH]) ratio increasing from 0.6 to 1.0, their mechanical properties were gradually increased. This study provided some insight into the microwave-assisted liquefied lignin polyols for the production of rigid PU foam.

Size-dependent photocatalytic activity of La0.8Sr0.2MnO3 nanoparticles prepared by hydrothermal synthesis

NASA Astrophysics Data System (ADS)

Rahmani Afje, F.; Ehsani, M. H.

2018-04-01

Synthesize of La0.8Sr0.2MnO3 (LSMO) manganite were carried out in different particle sizes by hydrothermal method. Structural and optical properties of the prepared specimens were studied by x-ray diffraction (XRD), Fourier transform infra-red (FT-IR) spectroscopy, field emission scanning electron microscopy (FESEM), and UV–vis spectroscopy. The XRD study, coupled with the Rietveld refinement, exhibited rhombohedral structure with R-3C space group. Using the FT-IR and FESEM analyses, the perovskite structure of the samples with Nano-rod-like morphologies were inferred. Furthermore, the average sizes of 48.11, 70.99 and 111.45 nm were obtained for the ones sintered at 800, 900, and 1000 °C temperatures, respectively. The optical research showed that band gap energy is about 2.13 eV, being suitable in visible-light photocatalytic activity for water purification from dyes and toxic organic materials. The photo-degradation efficiency for decolorizing methyl orange solution (10 ppm) for various samples (100 ppm) were systematically probed and a strong relation is concluded between particle size and photocatalytic activity.

FT-IR spectroscopy for rapid differentiation of Aspergillus flavus, Aspergillus fumigatus, Aspergillus parasiticus and characterization of aflatoxigenic isolates collected from agricultural environments.

PubMed

Garon, David; El Kaddoumi, Anne; Carayon, Alexandra; Amiel, Caroline

2010-08-01

In agricultural areas, Aspergillus flavus, Aspergillus fumigatus and Aspergillus parasiticus are commonly identified in various feedstuffs and bioaerosols originated from feed handling. Some isolates belonging to these fungal species could produce mycotoxins and constitute a risk factor for human and animal health. In this study, Fourier-transform infrared spectroscopy was used for a rapid detection and characterization of 99 isolates collected from agricultural areas. The results showed a first cluster corresponding to strains previously attributed to the A. fumigatus group according to current taxonomic concepts, and a second cluster divided in 2 groups around reference strains of A. flavus and A. parasiticus species. The toxigenic capacity of isolates was evaluated by high performance liquid chromatography coupled to mass spectrometry. In the A. flavus group, only 6 strains of A. parasiticus and 4 strains of A. flavus were able to produce aflatoxins on culture media. FT-IR spectroscopy, respectively, allowed the differentiation of non-toxigenic and toxigenic A. flavus and A. parasiticus isolates at 75 and 100%. Discrimination between toxigenic and non-toxigenic A. fumigatus was not possible because all of the isolates produced at least one mycotoxin.

A novel approach for synthesis of zwitterionic polyurethane coating with protein resistance.

PubMed

Wang, Chunhua; Ma, Chunfeng; Mu, Changdao; Lin, Wei

2014-11-04

We have developed a novel approach to introduce zwitterions into polyurethane for the preparation of antibiofouling coating. First, the thiol-ene click reaction between 2-(dimethylamino)ethyl methacrylate (DMAEMA) and 3-mercapto-1,2-propanediol (TPG) is used to synthesize dihydroxy-terminated DMAEMA (DMA(OH)2) under UV catalysis. The product has been proved by gel permeation chromatography (GPC), Fourier transform infrared spectrum (FT-IR), proton nuclear magnetic resonance ((1)H NMR), and high resolution mass spectrometry (HRMS). DMA(OH)2 is then incorporated into polyurethane as side groups by polyaddition with diisocyanate and further reacts with 1,3-propane sultone to obtain the zwitterionic polyurethanes. The presence of sulfobetaine zwitterions side groups has been demonstrated by FT-IR and X-ray photoelectron spectroscopy (XPS). Thermal analysis indicates that the thermal stability is decreased with the increasing content of zwitterionions. The antibiofouling property of polyurethanes has been investigated by the measurement of adsorption of fibrinogen, bovine serum albumin (BSA), and lysozyme on the polyurethanes surface using quartz crystal microbalance with dissipation (QCM-D). The results show that the polyurethane coatings exhibit effective nonspecific protein resistance at higher content of zwitterionic side groups.

Isolation and structural characterization of a novel sibutramine analogue, chlorosipentramine, in a slimming dietary supplement, by using HPLC-PDA, LC-Q-TOF/MS, FT-IR, and NMR.

PubMed

Yun, Jisuk; Shin, Kye Jung; Choi, Jangduck; Jo, Cheon-Ho

2018-05-01

A novel sibutramine analogue was detected in a slimming formula by high performance liquid chromatography with a photo diode detector array (HPLC-PDA). The unknown compound exhibited an ultraviolet (UV) spectrum that was similar to that of chlorosibutramine, despite having a different HPLC retention time. Further analysis of the slimming formula by LC-quadrupole time-of-flight mass spectrometry (LC-Q-TOF/MS) showed that the unknown compound had the formula C 18 H 27 Cl 2 N. To elucidate the structure of this new sibutramine analogue, the target compound in the slimming formula was isolated on a preparative-LC system equipped with a PDA. After analysis by fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy, the unknown compound was identified as a sibutramine analogue in which the iso-butyl group on the side chain is replaced with an iso-pentyl group. This new sibutramine analogue was identified to be 1-(1-(3,4-dichlorophenyl)cyclobutyl)-N,N,4-trimethylpentan-1-amine and has been named as chlorosipentramine. Copyright © 2018 Elsevier B.V. All rights reserved.

Single Cell Synchrotron FT-IR Microspectroscopy Reveals a Link between Neutral Lipid and Storage Carbohydrate Fluxes in S. cerevisiae

PubMed Central

Jamme, Frédéric; Vindigni, Jean-David; Méchin, Valérie; Cherifi, Tamazight; Chardot, Thierry; Froissard, Marine

2013-01-01

In most organisms, storage lipids are packaged into specialized structures called lipid droplets. These contain a core of neutral lipids surrounded by a monolayer of phospholipids, and various proteins which vary depending on the species. Hydrophobic structural proteins stabilize the interface between the lipid core and aqueous cellular environment (perilipin family of proteins, apolipoproteins, oleosins). We developed a genetic approach using heterologous expression in Saccharomyces cerevisiae of the Arabidopsis thaliana lipid droplet oleosin and caleosin proteins AtOle1 and AtClo1. These transformed yeasts overaccumulate lipid droplets, leading to a specific increase in storage lipids. The phenotype of these cells was explored using synchrotron FT-IR microspectroscopy to investigate the dynamics of lipid storage and cellular carbon fluxes reflected as changes in spectral fingerprints. Multivariate statistical analysis of the data showed a clear effect on storage carbohydrates and more specifically, a decrease in glycogen in our modified strains. These observations were confirmed by biochemical quantification of the storage carbohydrates glycogen and trehalose. Our results demonstrate that neutral lipid and storage carbohydrate fluxes are tightly connected and co-regulated. PMID:24040242

Investigation of the interaction between naringin and human serum albumin

NASA Astrophysics Data System (ADS)

Zhang, Yaheng; Li, Ying; Dong, Lijun; Li, Jiazhong; He, Wenying; Chen, Xingguo; Hu, Zhide

2008-03-01

The interaction between naringin and human serum albumin (HSA) has been thoroughly studied by fluorescence quenching technique in combination with UV absorption spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, circular dichroism (CD) spectroscopy and molecular modeling method. Under the simulative physiological conditions, fluorescence data revealed the presence of the binding site on HSA and its binding constants ( K) are 1.62 × 10 4, 1.68 × 10 4, 1.72 × 10 4, and 1.79 × 10 4 M -1 at 289, 296, 303, and 310 K, respectively. The alterations of protein secondary structure in the presence of naringin aqueous solution were qualitative and quantitative calculated by the evidence from CD and FT-IR spectroscopes. In addition, according to the Van't Hoff equation, the thermodynamic functions standard enthalpy (Δ H0) and standard entropy (Δ S0) for the reaction were calculated to be 3.45 kJ mol -1 and 92.52 J mol -1 K -1. These results indicated that naringin binds to HSA mainly by a hydrophobic interaction. Furthermore, the displacement experiments confirmed that naringin could bind to the site I of HSA, which was also in agreement with the result of the molecular modeling study.

Eco-friendly synthesis of cuprous oxide (Cu2O) nanoparticles and improvement of their solar photocatalytic activities

NASA Astrophysics Data System (ADS)

Kerour, A.; Boudjadar, S.; Bourzami, R.; Allouche, B.

2018-07-01

In this work, we have synthesized cuprous oxide (Cu2O) nanoparticles with octahedral and spherical like shapes by an ecofriendly, simple and coast effective method, by using the aqueous extract of Aloe vera and copper sulfate as solvent and precursor respectively. The effect of Aloe vera aqueous extract concentration on the morphological, structural and optical properties of as synthesized nanoparticles was studied by Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform (FT-IR) spectroscopy and UV-visible diffuse reflectance. The SEM images showing octahedral and spherical agglomeration of nanoparticles. The cubic structure of Cu2O was confirmed by XRD analysis, the crystallites size depends to the concentration of Aloe vera aqueous extract with an average size ranged between 24 and 61 nm. The FT-IR vibration measurements valid the presence of pure Cu2O in the samples. The UV-visible spectra show that the prepared cuprous oxide (Cu2O) has a gap energy estimated from 2.5 to 2.62 eV. The photocatalytic activities of the as-prepared material were highly improvement by the fast degradation of methylene blue in aqueous solution at room temperature under solar simulator irradiation.

Synthesis and characterization of silver nanoparticles using crystal compound of sodium para-hydroxybenzoate tetrahydrate isolated from Vitex negundo. L leaves and its apoptotic effect on human colon cancer cell lines.

PubMed

Durai, Prabhu; Chinnasamy, Arulvasu; Gajendran, Babu; Ramar, Manikandan; Pappu, Srinivasan; Kasivelu, Govindaraju; Thirunavukkarasu, Ashokkumar

2014-09-12

Metallic nanoparticles are major concern, particularly silver nanoparticles (AgNPs) are used in various applications. In the present investigation, we report a novel strategy with biological approach for synthesis of AgNPs using sodium para-hydroxybenzoate tetrahydrate (SPHT) isolated from Vitex negundo leaves. The synthesized SPHT-AgNPs were characterized by UV-vis spectroscopy, high resolution transmission electron microscopy (HRTEM) with selected area electron diffraction (SAED) pattern, field emission scanning electron microscopy (FESEM) with energy-dispersive X-ray spectroscopy (EDX), zeta potential and Fourier transform infrared spectroscopy (FT-IR) analysis. The various pH and temperature were evaluated to find their stability effects on SPHT-AgNPs synthesis peak at 430 nm. The size of SPHT-AgNPs were ranging from 26 to 39 nm and were spherical in shape. The hydroxyl and carboxylic functional groups from bio-reducing mediators of SPHT have a stronger ability towards synthesis of AgNPs, which was confirmed using FT-IR spectrum. In addition, anticancer activity were determined by MTT assay, Annexin V-FITC/PI and cell cycle analysis. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Installation of a reactive site for covalent wiring onto an intrinsically conductive poly(ionic liquid)

DOE PAGES

Brombosz, Scott M.; Lee, Sungwon; Firestone, Millicent A.

2014-11-04

We describe post-polymerization radical bromination of a nanostructured poly(ionic liquid) that selectively introduces a reactive bromo-group onto the polyalkylthiophene backbone. Raman and FT-IR spectroscopy proves that the bromine is successfully introduced at the 3-methyl position of the thiophene and that the molecular structure of the polymer remains largely intact with only minimal chain scission detected. FT-IR and Vis-NIR spectroscopy indicates that incorporation of the bromine induces twisting (loss of co-planarity) of the polythiophene backbone. WAXS confirms retention of an ordered lamellar structure with minor lattice spacing contraction. Cyclic voltammetry confirms spectroscopic findings that the bromination reaction yields a stable p-dopedmore » polymer. The installed bromine is susceptible to nucleophilic displacement permitting the covalent attachment of other functional molecules, such as a dialkylphosphonate. Elemental analysis of such a transformation established that 100 % functionalization can be achieved. These results collectively demonstrate that post-modification of a π-conjugated polymer can be used to both tune electronic and photonic properties, as well as install a chemoselective attachment point for the covalent wiring of other molecules.« less

Green synthesis and characterization of graphene nanosheets

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

Tavakoli, Farnosh; Salavati-Niasari, Masoud, E-mail: salavati@kashanu.ac.ir; Department of Inorganic Chemistry, Faculty of Chemistry, University of Kashan, Kashan, P. O. Box. 87317-51167, Islamic Republic of Iran

Highlights: • For the first time, we have synthesized graphene nanosheets in the presence of pomegranate juice. • Here pomegranate juice was used not only as reductant but also as capping agent. • FT-IR, XRD, SEM, EDS and TEM were used to characterize the samples. • According to TEM image, graphene nanosheet is individually exfoliated after stirring for 24 h. • As shown in the TEM image, graphene monolayer is obtained. - Abstract: For the first time, we have successfully synthesized graphene nanosheets in the presence of pomegranate juice. In this approach, pomegranate juice was used not only as reductantmore » but also as capping agent to form graphene nanosheets. At first, the improved Hummer method to oxidize graphite for the synthesis of graphene oxide (GO) was applied, and then the as-produced graphene oxide was reduced by pomegranate juice to form graphene nanosheets. Fourier transformed infrared (FT-IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), high resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM) and raman were used to characterize the samples. The results obtained from the characterization techniques proved high purity of the final products.« less

Development of search prefilters for infrared library searching of clear coat paint smears.

PubMed

Lavine, Barry K; Fasasi, Ayuba; Mirjankar, Nikhil; Sandercock, Mark

2014-02-01

Search prefilters developed from spectral data collected on two 6700 Thermo-Nicolet FTIR spectrometers were able to identify the respective manufacturing plant and the production line of an automotive vehicle from its clear coat paint smear using IR transmission spectra collected on a Bio-Rad 40A or Bio-Rad 60 FTIR spectrometer. All four spectrometers were equipped with DTGS detectors. An approach based on instrumental line functions was used to transfer the classification model between the Thermo-Nicolet and Bio-Rad instruments. In this study, 209 IR spectra of clear coat paint smears comprising the training set were collected using two Thermo-Nicolet 6700 IR spectrometers, whereas the validation set consisted of 242 IR spectra of clear coats obtained using two Bio-Rad FTIR instruments. © 2013 Published by Elsevier B.V.

Application of infrared spectroscopy in the identification of Ewing sarcoma: A preliminary report

NASA Astrophysics Data System (ADS)

Chaber, Radosław; Łach, Kornelia; Szmuc, Kamil; Michalak, Elżbieta; Raciborska, Anna; Mazur, Damian; Machaczka, Maciej; Cebulski, Józef

2017-06-01

Fourier transform infrared (FTIR) spectroscopy is a highly sensitive, non-invasive analytical technique that can provide information about molecular changes in a biological sample. FTIR spectrum is a sum of the frequencies of many biomolecules which reveals a biochemical fingerprint for mineral identification, and can be analyzed for information about the mineral structure of malignant cells. This gives us the potential to differentiate tumor cells from normal cells in the early stage of relapse, before the tumor cells would be detectable in light microscopy. Ewing sarcoma (ES) is the second most common malignant bone tumor found in children and adolescents. ES affects annually almost 3 persons/1,000,000 mostly children and young adults under 20 years of age annually. ES originates from primitive, low-differentiated neuroectodermal cells. The current standard of therapy for ES is the surgical resection of the primary tumor and metastasis in combination with the chemo- and radiotherapy. The aim of this study was to compare the spectra of ES bone samples and the spectra of normal bone tissues, analyzed before and after induction chemotherapy, by means of FTIR spectroscopy. Six patients with ES affecting bones aged 5.5-16.5 years (median age 11.2 years), who were treated between 2011 and 2015, were included to the study. In all analyzed patients, the diagnosis of ES and the assessment of response to the chemotherapy were performed according to the Euro-EWING-2008 protocol. The Fourier transform infrared spectroscope (FT-IR; Vertex 70v from Bruker) was used in this study. Tissue specimens were applied to the attenuated total reflection (ATR) in the infrared (IR) radiation from the mid-infrared range using a single-reflection snap ATR crystal diamond. In the FTIR spectra we observed a shift in the wave number of the phosphate ion (from 3 to 26 [cm-1]) associated with the presence of tumor tissue. After chemotherapy, a change of the FTIR spectrum was associated with the ES's histopathological response. In patients with a high ratio of the necrotic cells in the tumor (>90% of cells) after chemotherapy, we showed a shift of the peak ⧹ absorption bands to the higher wave numbers. In contrast, in patients with a poor chemotherapy response (<30% of necrotic cells in the tumor), we observed a decline in the peak absorption bands to the lower wave numbers. The results showed that analysis of the spectrum changes of tissue specimens in ES can be helpful in the assessment of clinical response to cancer therapy. It seems that FTIR spectroscopy is a valuable tool for his purpose. The issue awaits full elucidation in further studies on larger groups of patients with ES.

Rapid, accurate, and comparative differentiation of clinically and industrially relevant microorganisms via multiple vibrational spectroscopic fingerprinting.

PubMed

Muhamadali, Howbeer; Subaihi, Abdu; Mohammadtaheri, Mahsa; Xu, Yun; Ellis, David I; Ramanathan, Rajesh; Bansal, Vipul; Goodacre, Royston

2016-08-15

Despite the fact that various microorganisms (e.g., bacteria, fungi, viruses, etc.) have been linked with infectious diseases, their crucial role towards sustaining life on Earth is undeniable. The huge biodiversity, combined with the wide range of biochemical capabilities of these organisms, have always been the driving force behind their large number of current, and, as of yet, undiscovered future applications. The presence of such diversity could be said to expedite the need for the development of rapid, accurate and sensitive techniques which allow for the detection, differentiation, identification and classification of such organisms. In this study, we employed Fourier transform infrared (FT-IR), Raman, and surface enhanced Raman scattering (SERS) spectroscopies, as molecular whole-organism fingerprinting techniques, combined with multivariate statistical analysis approaches for the classification of a range of industrial, environmental or clinically relevant bacteria (P. aeruginosa, P. putida, E. coli, E. faecium, S. lividans, B. subtilis, B. cereus) and yeast (S. cerevisiae). Principal components-discriminant function analysis (PC-DFA) scores plots of the spectral data collected from all three techniques allowed for the clear differentiation of all the samples down to sub-species level. The partial least squares-discriminant analysis (PLS-DA) models generated using the SERS spectral data displayed lower accuracy (74.9%) when compared to those obtained from conventional Raman (97.8%) and FT-IR (96.2%) analyses. In addition, whilst background fluorescence was detected in Raman spectra for S. cerevisiae, this fluorescence was quenched when applying SERS to the same species, and conversely SERS appeared to introduce strong fluorescence when analysing P. putida. It is also worth noting that FT-IR analysis provided spectral data of high quality and reproducibility for the whole sample set, suggesting its applicability to a wider range of samples, and perhaps the most suitable for the analysis of mixed cultures in future studies. Furthermore, our results suggest that while each of these spectroscopic approaches may favour different organisms (sample types), when combined, they would provide complementary and more in-depth knowledge (structural and/or metabolic state) of biological systems. To the best of our knowledge, this is the first time that such a comparative and combined spectroscopic study (using FT-IR, Raman and SERS) has been carried out on microbial samples.

Studies on Thorium Adsorption Characteristics upon Activated Titanium Hydroxide Prepared from Rosetta Ilmenite Concentrate

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

Gado, M, E-mail: parq28@yahoo.com; Zaki, S

2016-01-01

The titanium hydroxide prepared from Rosetta ilmenite concentrate has been applied for Th (IV) adsorption from its acid aqueous solutions. The prepared hydroxide is first characterized by both Fourier transform infrared (FT-IR) spectrum and thermogravimetric analysis. The relevant factors affecting the adsorption process have been studied. The obtained equilibrium data fits well with the Langmuir isotherm rather than Freundlich isotherm, while the adsorption kinetic data follow the pseudo-second order model. The different thermodynamic parameters have also been calculated and indicate that the adsorption process is spontaneous.

Synthesis and Characterization of Rhodamine B-ethylenediamine-hyaluronan Acid as Potential Biological Functional Materials

NASA Astrophysics Data System (ADS)

Li, Y. L.; Wang, W. X.; Wang, Y.; Zhang, W. B.; Gong, H. M.; Liu, M. X.

2018-05-01

The purpose of this study is to synthesize and characterize fluorescent polymers, rhodamine B-ethylenediamine-hyaluronan acid (RhB-EA-HA). RhB-EA-HA was successfully synthesized by ester ammonolysis reaction and amidation reaction. Moreover, the structural properties of RhB-EA-HA were characterized by 1H-NMR spectra, UV-vis spectrometry and Fourier transform infrared spectroscopy (FT-IR). RhB-EA-HA can be grafted on the surface of silica nanomaterials, which may be potential biological functional materials for drug delivery system.

A simple method to synthesize polyhedral hexagonal boron nitride nanofibers

NASA Astrophysics Data System (ADS)

Lin, Liang-xu; Zheng, Ying; Li, Zhao-hui; shen, Xiao-nv; Wei, Ke-mei

2007-12-01

Hexagonal boron nitride (h-BN) fibers with polyhedral morphology were synthesized with a simple-operational, large-scale and low-cost method. The sample obtained was studied by X-ray photoelectron spectrometer (XPS), electron energy lose spectroscopy (EELS), X-ray powder diffraction (XRD), Fourier transformation infrared spectroscopy (FT-IR), etc., which matched with h-BN. Environment scanning electron microscopy (ESEM) and transmission electron microscope (TEM) indicated that the BN fibers possess polyhedral morphology. The diameter of the BN fibers is mainly in the range of 100-500 nm.

Solvothermal synthesis of fusiform hexagonal prism SrCO{sub 3} microrods via ethylene glycol solution

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

Shi Liange; Du Fanglin

2007-08-07

Fusiform hexagonal prism SrCO{sub 3} microrods were prepared by a simple solvothermal route at 120 deg. C, and characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and Fourier transform infrared (FT-IR) spectroscopy. By controlling the content of ethylene glycol (EG), it was found that ethylene glycol (EG) played an important role in the formation of such SrCO{sub 3} microrods. Finally, effects of other solvents on the products, including 1,2-propanediol and glycerin, were also investigated.

Structure and thermal decomposition of sulfated β-cyclodextrin intercalated in a layered double hydroxide

NASA Astrophysics Data System (ADS)

Wang, Ji; Wei, Min; Rao, Guoying; Evans, David G.; Duan, Xue

2004-01-01

The sodium salt of hexasulfated β-cyclodextrin has been synthesized and intercalated into a magnesium-aluminum layered double hydroxide by ion exchange. The structure, composition and thermal decomposition behavior of the intercalated material have been studied by variable temperature X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), inductively coupled plasma emission spectroscopy (ICP), and thermal analysis (TG-DTA) and a model for the structure has been proposed. The thermal stability of the intercalated sulfated β-cyclodextrin is significantly enhanced compared with the pure form before intercalation.

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

Catauro, Michelina; Bollino, Flavia; Gloria, Antonio

The objective of the present study was to synthesize and to characterize Silica/polyethylene glycol (SiO{sub 2}/PEG) organic-inorganic hybrid materials containing a high polymer amount (60 and 70 wt%) for biomedical applications. Scanning electron microscopy (SEM) showed that the samples are homogeneous on the nanometer scale, confirming that they are nanocomposites. Fourier transform infrared spectroscopy (FT-IR) proved that the materials are class I hybrids because the two phases (SiO{sub 2} and PEG) interact by hydrogen bonds. To evaluate the possibility of using them in the biomedical field, the bioactivity and biocompatibility of the synthesized hybrids have been ascertained. The formation ofmore » a hydroxyapatite layer was observed on the hybrid surface by SEM/EDX and FTIR after soaking in simulated body fluid (SBF). Moreover, their biocompatibility was assessed by performing WST-8 cytotoxicity assay in vitro.« less

Influence of Brij58 on the Characteristic and Performance of PES Membrane for Water Treatment Process

NASA Astrophysics Data System (ADS)

Mukramah; Syawaliah; Mulyati, S.; Arahman, N.

2017-03-01

This study proposes a modification of polyether sulfone (PES) membrane by blending the polymer with a hydrophilic additive of Brij-58. Flat-sheet PES membrane was prepared through a non-solvent induced phase separation (NIPS) method using dimethylformamide (DMF) as a solvent. PES membrane was modified by adding Brij-58 into dope solution at a different concentration, i.e 1, 3, 5, 7, and 10 wt %. The fabricated membranes were characterized by means of Scanning Electron Microscopy (SEM) and Fourier Transform Infra-Red (FTIR) spectroscopy. Filtration performance of membrane was analyzed by using a dead-end module. It is found that the addition of a small amount of Brij into polymer solution brought about the increase of water flux. FT-IR investigation showed that the additive exist on the surface of a blended membrane.

Synthesis and effect of modification on methacylate - acrylate microspheres for Trametes versicolor laccase enzyme immobilization

NASA Astrophysics Data System (ADS)

Mazlan, Siti Zulaikha; Hanifah, Sharina Abu

2014-09-01

Immobilization of laccase on the modified copolymer methacrylate-acrylate microspheres was studied. A poly (glycidyl methacrylate-co-n-butyl acrylate) microsphere consists of epoxy groups were synthesized using suspension photocuring technique. The epoxy group in poly (GMA-nBA) microspheres were converted into amino groups with aldehyde group. Laccase immobilization is based on having the amino groups on the enzyme surface and aldehyde group on the microspheres via covalent binding. Fourier transform infrared spectroscopy (FT-IR) analysis proved the successful surface modification on microspheres. The FTIR spectrum shows the characteristic peaks at 1646 cm-1 assigned to the conformation of the polymerization that took place between monomer GMA and nBA respectively. In addition, after modification, FTIR peaks that assigned to the epoxy ring (844 cm-1 and 904 cm-1) were decreased. The results obtained from FTIR method signify good agreement with the epoxy content method. Hence, the activity of the laccase-immobilized microspheres increased upon increasing the epoxy content. Furthermore, poly (GMA-nBA) exhibited uniform microspheres with below 2 μm surface. Immobilized enzyme showed a broader pH profile and higher temperature compared native enzyme.

FT-IR remote sensing of atmospheric species: Application to global change and air pollution

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

Vazquez, G.J.

1995-12-31

In this contribution, the author describes two applications of Fourier Transform Infrared Spectroscopy to the monitoring of atmospheric compounds. Firstly, the author reports FTIR solar spectroscopy measurements carried out at ground level at NCAR and on airplanes employing a spectrometer of 0.06 cm{sup -1} resolution. Sample atmospheric spectra and fitting examples are presented for key species relevant to stratospheric chemistry and global change: ozone (O{sub 3}), a chlorofluorocarbon (CF{sub 2}Cl{sub 2}), a greenhouse gas (N{sub 2}O), HCl, NO and HNO{sub 3}. Secondly, the author briefly describes urban air pollution measurements at an intersection with heavy traffic in Tucson, AZ. Twomore » FTIR spectrometers of 1 cm{sup -1} resolution were employed to carry out long-path open-path measurements of the CO/CO{sub 2} ratio and SF{sub 6}. Two FEAT and two LPUV instruments were employed for ancillary measurements of CO, CO{sub 2}, NO, and aromatic hydrocarbons. Measurements of CO at two heights and a comparison of CO/CO{sub 2} ratios obtained by FEAT exhaust emission and FTIR ambient air measurements are reported.« less

Novel method for early investigation of bioactivity in different borate bio-glasses

NASA Astrophysics Data System (ADS)

Abdelghany, A. M.

Some ternary borate glasses were prepared and corrosion behavior of such ternary borate glasses after immersion in aqueous dilute phosphate solution was studied using different immersion times. Fourier transform infrared (FTIR) absorption spectral measurements were done before and after immersion in the mentioned solution for extended times up to 2 days to justify the appearance of the characteristic FTIR bands due to calcium phosphate (hydroxyapatite (HA)) which is considered as the potential indication of bioactivity. Experimental IR data confirm the beginning of the appearance of FTIR bands at about 580 and 620 cm-1 after 3 days and the complete resolution with its characteristic split form after 1 week and more. Deconvolution analysis technique (DAT) of the FTIR spectrum was employed to investigate the bioactivity of such ternary borate system after a short period of immersion. The corrosion behavior of such glasses is explained in relation to a suggested hydrolysis followed by direct dissolution mechanism. The ease of dissolution of all the borate glasses constituents explains the formation of calcium phosphate and conversion to crystalline hydroxyapatite within the borate glass matrix. X-ray diffraction may be used to retrace the structural changes and degree of crystallinity of the prepared glasses.

Exploiting external reflection FTIR spectroscopy for the in-situ identification of pigments and binders in illuminated manuscripts. Brochantite and posnjakite as a case study

NASA Astrophysics Data System (ADS)

Zaffino, Chiara; Guglielmi, Vittoria; Faraone, Silvio; Vinaccia, Alessandro; Bruni, Silvia

2015-02-01

In the present work, the use of portable instrumentation allowing in-situ reflection FTIR analyses is exploited to identify the coloring matters of northern-Italian illuminations dating to the XVI century. In order to build a database of spectra, reference paint samples were prepared spreading the pigments on parchment with two different binders, i.e. gum arabic and egg white, used in antiquity. Pigments for the database were chosen considering their use in the Middle Ages and in the Renaissance and their response in the mid- and near-IR region. The reflection FTIR spectra obtained resulted to be dominated by the specular reflection component, allowing the use of the Kramers-Kronig transform to convert them to the more conventional absorbance FTIR spectra. Several pigments could thus be identified in ancient illuminations, even if some green details showed a spectral pattern different with respect to the most common commercial green pigments of the database. Therefore, in addition, basic copper sulfates brochantite and posnjakite were synthesized and characterized. In three green details, posnjakite was identified, both as a pure compound and together with malachite.

Exploiting external reflection FTIR spectroscopy for the in-situ identification of pigments and binders in illuminated manuscripts. Brochantite and posnjakite as a case study.

PubMed

Zaffino, Chiara; Guglielmi, Vittoria; Faraone, Silvio; Vinaccia, Alessandro; Bruni, Silvia

2015-02-05

In the present work, the use of portable instrumentation allowing in-situ reflection FTIR analyses is exploited to identify the coloring matters of northern-Italian illuminations dating to the XVI century. In order to build a database of spectra, reference paint samples were prepared spreading the pigments on parchment with two different binders, i.e. gum arabic and egg white, used in antiquity. Pigments for the database were chosen considering their use in the Middle Ages and in the Renaissance and their response in the mid- and near-IR region. The reflection FTIR spectra obtained resulted to be dominated by the specular reflection component, allowing the use of the Kramers-Kronig transform to convert them to the more conventional absorbance FTIR spectra. Several pigments could thus be identified in ancient illuminations, even if some green details showed a spectral pattern different with respect to the most common commercial green pigments of the database. Therefore, in addition, basic copper sulfates brochantite and posnjakite were synthesized and characterized. In three green details, posnjakite was identified, both as a pure compound and together with malachite. Copyright © 2014 Elsevier B.V. All rights reserved.

Attenuated total reflectance FT-IR imaging and quantitative energy dispersive-electron probe X-ray microanalysis techniques for single particle analysis of atmospheric aerosol particles.

PubMed

Ryu, JiYeon; Ro, Chul-Un

2009-08-15

This work demonstrates the practical applicability of the combined use of attenuated total reflectance (ATR) FT-IR imaging and low-Z particle electron probe X-ray microanalysis (EPMA) techniques for the characterization of individual aerosol particles. These two single particle analytical techniques provide complementary information on the physicochemical characteristics of the same individual particles, that is, the low-Z particle EPMA for the information on the morphology and elemental concentration and the ATR-FT-IR imaging on the functional group, molecular species, and crystal structure. It was confirmed that the ATR-FT-IR imaging technique can provide sufficient FT-IR absorption signals to perform molecular speciation of individual particles of micrometer size when applied to artificially generated aerosol particles such as ascorbic acid and NaNO(3) aerosols. An exemplar indoor atmospheric aerosol sample was investigated to demonstrate the practical feasibility of the combined application of ATR-FT-IR imaging and low-Z particle EPMA techniques for the characterization of individual airborne particles.

Characterization and identification of microorganisms by FT-IR microspectrometry

NASA Astrophysics Data System (ADS)

Ngo-Thi, N. A.; Kirschner, C.; Naumann, D.

2003-12-01

We report on a novel FT-IR approach for microbial characterization/identification based on a light microscope coupled to an infrared spectrometer which offers the possibility to acquire IR-spectra of microcolonies containing only few hundred cells. Microcolony samples suitable for FT-IR microspectroscopic measurements were obtained by a replica technique with a stamping device that transfers spatially accurate cells of microcolonies growing on solid culture plates to a special, IR-transparent or reflecting stamping plate. High quality spectra could be recorded either by applying the transmission/absorbance or the reflectance/absorbance mode of the infrared microscope. Signal to noise ratios higher than 1000 were obtained for microcolonies as small as 40 μm in diameter. Reproducibility levels were established that allowed species and strain identification. The differentiation and classification capacity of the FT-IR microscopic technique was tested for different selected microorganisms. Cluster and factor analysis methods were used to evaluate the complex spectral data. Excellent discrimination between bacteria and yeasts, and at the same time Gram-negative and Gram-positive bacterial strains was obtained. Twenty-two selected strains of different species within the genus Staphylococcus were repetitively measured and could be grouped into correct species cluster. Moreover, the results indicated that the method allows also identifications at the subspecies level. Additionally, the new approach allowed spectral mapping analysis of single colonies which provided spatially resolved characterization of growth heterogeneity within complex microbial populations such as colonies.

Characterization of Organosolv Lignins using Thermal and FT-IR Spectroscopic Analysis

Treesearch

Rhea J. Sammons; David P. Harper; Nicole Labbe; Joseph J. Bozell; Thomas Elder; Timothy G. Rials

2013-01-01

A group of biomass-derived lignins isolated using organosolv fractionation was characterized by FT-IR spectral and thermal property analysis coupled with multivariate analysis. The principal component analysis indicated that there were significant variations between the hardwood, softwood, and grass lignins due to the differences in syringyl and guaiacyl units as well...

Pharmacokinetics Evaluation of Carbon Nanotubes Using FTIR Analysis and Histological Analysis.

PubMed

Gherman, Claudia; Tudor, Matea Cristian; Constantin, Bele; Flaviu, Tabaran; Stefan, Razvan; Maria, Bindea; Chira, Sergiu; Braicu, Cornelia; Pop, Laura; Petric, Roxana Cojocneanu; Berindan-Neagoe, Ioana

2015-04-01

Carbon nanotubes (CNTs) are biologically non-toxic and long-circulating nanostructures that have special physical properties. This study was focused on developing alternative methods that track carbon nanotubes, like FR-IR to classical tissue histological procedure. FT-IR absorption spectra were used to confirm the carboxylation of carbon nanotubes and to evaluate the presence of carbon nanotubes from bulk spleen samples and histologically prepared samples (control spleen and spleen with SWCNT-COOH). FT-IR spectrum of spleen sample from animals injected with CNTs shows major spectral differences consisting in infrared bands located at ~1173 cm(-1), ~ 1410 cm(-1); ~1658 cm(-1), ~1737 cm(-1) and around 1720 cm(-1) respectively. In terms of localization of carbon nanotubes, selective accumulation of marginal zone macrophages and splenic red pulp is observed for all treated groups, indicating the presence of carbon nanotubes even at 3, 4 and 7 days after treatment. In summary, we believe that histological evaluation and FT-IR can provide more characteristic information about the pharmacokinetcis and the clearance of carbon nanotubes.

Analysis of clay smoking pipes from archeological sites in the region of the Guanabara Bay (Rio de Janeiro, Brazil) by FT-IR

NASA Astrophysics Data System (ADS)

Freitas, Renato P.; Ribeiro, Iohanna M.; Calza, Cristiane; Oliveira, Ana L.; Silva, Mariane L.; Felix, Valter S.; Ferreira, Douglas S.; Coelho, Felipe A.; Gaspar, Maria D.; Pimenta, André R.; Medeiros, Elanio A.; Lopes, Ricardo T.

2016-06-01

In this study, twenty samples of clay smoking pipes excavated in an 18 km2 area between the Macacu and Caceribu rivers, in the municipality of Itaboraí, Rio de Janeiro, Brazil were analyzed by FT-IR technique. The samples, excavated in different archeological sites of the region, are dated between the seventeenth and the nineteenth centuries and are part of the material culture left by Africans and African descendants that lived in the complex. FT-IR analyses and complementary SEM-EDS studies showed that the clay paste used in the manufacture of smoking pipes, mostly handcrafted, is composed of quartz, feldspar, phyllosilicates and iron oxides. Multivariate statistical tests (PCA) were applied to FT-IR data to assess the interactions between the archeological sites. The results indicated that one archeological site - Macacu IV - is greatly related to the other sites. The results obtained have helped archeologists and anthropologists in better understanding the manufacturing process employed in ancient ceramic artifacts produced during the period of colonial Brazil.

Analysis of clay smoking pipes from archeological sites in the region of the Guanabara Bay (Rio de Janeiro, Brazil) by FT-IR.

PubMed

Freitas, Renato P; Ribeiro, Iohanna M; Calza, Cristiane; Oliveira, Ana L; Silva, Mariane L; Felix, Valter S; Ferreira, Douglas S; Coelho, Felipe A; Gaspar, Maria D; Pimenta, André R; Medeiros, Elanio A; Lopes, Ricardo T

2016-06-15

In this study, twenty samples of clay smoking pipes excavated in an 18km(2) area between the Macacu and Caceribu rivers, in the municipality of Itaboraí, Rio de Janeiro, Brazil were analyzed by FT-IR technique. The samples, excavated in different archeological sites of the region, are dated between the seventeenth and the nineteenth centuries and are part of the material culture left by Africans and African descendants that lived in the complex. FT-IR analyses and complementary SEM-EDS studies showed that the clay paste used in the manufacture of smoking pipes, mostly handcrafted, is composed of quartz, feldspar, phyllosilicates and iron oxides. Multivariate statistical tests (PCA) were applied to FT-IR data to assess the interactions between the archeological sites. The results indicated that one archeological site - Macacu IV - is greatly related to the other sites. The results obtained have helped archeologists and anthropologists in better understanding the manufacturing process employed in ancient ceramic artifacts produced during the period of colonial Brazil. Copyright © 2016 Elsevier B.V. All rights reserved.

Synthesis, spectroscopic, thermal and structural properties of [M(3-aminopyridine)2Ni(μ-CN)2(CN)2]n (M(II) = Co and Cu) heteropolynuclear cyano-bridged complexes

NASA Astrophysics Data System (ADS)

Kartal, Zeki

2016-01-01

Two novel cyano-bridged heteropolynuclear complexes, [Co(3-aminopyridine)2Ni(μ-CN)2(CN)2]n and [Cu(3-aminopyridine)2Ni(μ-CN)2(CN)2]n have been synthesized and characterized by elemental, thermal, FT-IR and FT-Raman spectroscopies. The structures of complexes have been determined by X-ray powder diffraction. The FT-IR and FT-Raman spectra of complexes have been recorded in the region of 3500-400 cm-1 and 3500-100 cm-1, respectively. General information was acquired about structural properties of these complexes from FT-IR and FT-Raman spectra by considering changes at characteristic peaks of the cyano group and 3AP. The splitting of the ν(Ctbnd N) stretching bands in the FT-IR spectra for complexes indicates the presence of terminal and bridging cyanides. The thermal behaviors of these complexes have been also investigated in the range of 25-950 °C using TG and DTG methods. Magnetic susceptibility measurements were made at room temperature using Gouy-balance.

Speciation of individual mineral particles of micrometer size by the combined use of attenuated total reflectance-Fourier transform-infrared imaging and quantitative energy-dispersive electron probe X-ray microanalysis techniques.

PubMed

Jung, Hae-Jin; Malek, Md Abdul; Ryu, JiYeon; Kim, BoWha; Song, Young-Chul; Kim, HyeKyeong; Ro, Chul-Un

2010-07-15

Our previous work demonstrated for the first time the potential of the combined use of two techniques, attenuated total reflectance FT-IR (ATR-FT-IR) imaging and a quantitative energy-dispersive electron probe X-ray microanalysis, low-Z particle EPMA, for the characterization of individual aerosol particles. In this work, the speciation of mineral particles was performed on a single particle level for 24 mineral samples, including kaolinite, montmorillonite, vermiculite, talc, quartz, feldspar, calcite, gypsum, and apatite, by the combined use of ATR-FT-IR imaging and low-Z particle EPMA techniques. These two single particle analytical techniques provide complementary information, the ATR-FT-IR imaging on mineral types and low-Z particle EPMA on the morphology and elemental concentrations, on the same individual particles. This work demonstrates that the combined use of the two single particle analytical techniques can powerfully characterize externally heterogeneous mineral particle samples in detail and has great potential for the characterization of airborne mineral dust particles.

Experimental (13C NMR, 1H NMR, FT-IR, single-crystal X-ray diffraction) and DFT studies on 3,4-bis(isoproylamino)cyclobut-3-ene-1,2-dione.

PubMed

Süleymanoğlu, Nevin; Ustabaş, Reşat; Alpaslan, Yelda Bingöl; Eyduran, Fatih; Ozyürek, Cengiz; Iskeleli, Nazan Ocak

2011-12-01

In this work, 3,4-bis(isoproylamino)cyclobut-3-ene-1,2-dione C(10)H(16)N(2)O(2) (I), was synthesized and characterized by (13)C NMR, (1)H NMR, FT-IR, UV-vis spectroscopy and single-crystal X-ray diffraction. DFT method with 6-31G(d,p) basis set has been used to calculate the optimized geometrical parameters, atomic charges, vibrational frequencies and chemical shift values. The calculated vibrational frequencies and chemical shift values are compared with experimental FT-IR and NMR spectra. The results of the calculation shows good agreement between experimental and calculated values of the compound I. The existence of N-H⋯O type intermolecular ve C-H⋯O type intramolecular hydrogen bonds can be deduced from differences between experimental and calculated results of FT-IR and NMR. In addition, the molecular electrostatic potential map and frontier molecular orbitals and electronic absorption spectra were performed at B3LYP/6-31G(d,p) level of theory. HOMO-LUMO electronic transition of 4.90 eV are derived from the contribution of the bands π→π* and n→π* The spectral results obtained from FT-IR, NMR and X-ray of I revealed that the compound I is in predominantly enamine tautomeric form, which was supported by DFT calculations. Copyright © 2011 Elsevier B.V. All rights reserved.

Advanced sampling techniques for hand-held FT-IR instrumentation

NASA Astrophysics Data System (ADS)

Arnó, Josep; Frunzi, Michael; Weber, Chris; Levy, Dustin

2013-05-01

FT-IR spectroscopy is the technology of choice to identify solid and liquid phase unknown samples. The challenging ConOps in emergency response and military field applications require a significant redesign of the stationary FT-IR bench-top instruments typically used in laboratories. Specifically, field portable units require high levels of resistance against mechanical shock and chemical attack, ease of use in restrictive gear, extreme reliability, quick and easy interpretation of results, and reduced size. In the last 20 years, FT-IR instruments have been re-engineered to fit in small suitcases for field portable use and recently further miniaturized for handheld operation. This article introduces the HazMatID™ Elite, a FT-IR instrument designed to balance the portability advantages of a handheld device with the performance challenges associated with miniaturization. In this paper, special focus will be given to the HazMatID Elite's sampling interfaces optimized to collect and interrogate different types of samples: accumulated material using the on-board ATR press, dispersed powders using the ClearSampler™ tool, and the touch-to-sample sensor for direct liquid sampling. The application of the novel sample swipe accessory (ClearSampler) to collect material from surfaces will be discussed in some detail. The accessory was tested and evaluated for the detection of explosive residues before and after detonation. Experimental results derived from these investigations will be described in an effort to outline the advantages of this technology over existing sampling methods.

Size controlled biogenic silver nanoparticles as antibacterial agent against isolates from HIV infected patients

NASA Astrophysics Data System (ADS)

Suganya, K. S. Uma; Govindaraju, K.; Kumar, V. Ganesh; Dhas, T. Stalin; Karthick, V.; Singaravelu, G.; Elanchezhiyan, M.

2015-06-01

Silver nanoparticles (AgNPs) are synthesized using biological sources due to its high specificity in biomedical applications. Herein, we report the size and shape controlled synthesis of AgNPs using the aqueous extract of blue green alga, Spirulina platensis. Size, shape and elemental composition of AgNPs were characterized using UV-vis spectroscopy, Fluorescence spectroscopy, FT-IR (Fourier Transform-Infrared Spectroscopy), FT-RS (Fourier Transform-Raman Spectroscopy), SEM-EDAX (Scanning Electron Microscopy-Energy Dispersive X-ray analysis) and HR-TEM (High Resolution Transmission Electron Microscopy). AgNPs were stable, well defined and monodispersed (spherical) with an average size of 6 nm. The synthesized AgNPs were tested for its antibacterial potency against isolates obtained from HIV patients.

Process control using fiber optics and Fourier transform infrared spectroscopy

NASA Astrophysics Data System (ADS)

Kemsley, E. K.; Wilson, Reginald H.

1992-03-01

A process control system has been constructed using optical fibers interfaced to a Fourier transform infrared (FT-IR) spectrometer, to achieve remote spectroscopic analysis of food samples during processing. The multichannel interface accommodates six fibers, allowing the sequential observation of up to six samples. Novel fiber-optic sampling cells have been constructed, including transmission and attenuated total reflectance (ATR) designs. Different fiber types have been evaluated; in particular, plastic clad silica (PCS) and zirconium fluoride fibers. Processes investigated have included the dilution of fruit juice concentrate, and the addition of alcohol to fruit syrup. Suitable algorithms have been written which use the results of spectroscopic measurements to control and monitor the course of each process, by actuating devices such as valves and switches.