Статті в журналах: "FTIR Spectra"

1

Cao, Zhen, Yongying Liu, and Jiancheng Zhao. "Efficient Discrimination of Some Moss Species by Fourier Transform Infrared Spectroscopy and Chemometrics." Journal of Spectroscopy 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/191796.

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Fourier transform infrared spectroscopy (FTIR) technique was used to classify 16 species from three moss families (Mielichhoferiaceae, Bryaceae, and Mniaceae). The FTIR spectra ranging from 4000 cm−1to 400 cm−1of the 16 species were obtained. To group the spectra according to their spectral similarity in a dendrogram, cluster analysis and principal component analysis (PCA) were performed. Cluster analysis combined with PCA was used to give a rough result of classification among the moss samples. However, some species belonging to the same genus exhibited very similar chemical components and similar FTIR spectra. Fourier self-deconvolution (FSD) was used to enhance the differences of the spectra. Discrete wavelet transform (DWT) was used to decompose the FTIR spectra ofMnium laevinerveandM. spinosum. Three scales were selected as the feature extracting space in the DWT domain. Results showed that FTIR spectroscopy combined with DWT was suitable for distinguishing different species of the same genus.

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2

Tsutsumi, Tamao, Alok Shah, Lisa M. T. Lam, Sanmarie Schlebusch, Annika Krueger, Ian Frazer, Phil Hugenholtz, et al. "2125. Staphylococcus Species Identification by Fourier Transform Infrared (FTIR) Spectroscopic Techniques: A Cross-Lab Study." Open Forum Infectious Diseases 6, Supplement_2 (October 2019): S720. http://dx.doi.org/10.1093/ofid/ofz360.1805.

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Abstract Background Staphylococcus aureus is well known to be associated with atopic dermatitis. Recent studies also report S. aureus presence in lesional skin of squamous cell carcinoma (SCC) and its precursor lesion, actinic keratosis (AK). Therefore, it is of potential clinical interest to monitor skin S. aureus colonization on AK lesions. Fourier transform infrared (FTIR) spectroscopy is a cost-effective, nondestructive, and reagent-free technique for rapid microbial identification. It is based on the use of spectral databases developed with well-characterized strains in conjunction with the application of multivariate statistical analysis to elaborate classification models. In the present cross-lab study, spectral databases containing FTIR spectra of over 1000 staphylococcal isolates obtained from reference and clinical microbiology laboratories across Canada were employed in the FTIR spectroscopic identification of Staphylococcus spp. isolated from AK, SCC and perilesional skin of patients at the Princess Alexandra Hospital Dermatology Clinic in Brisbane, Australia. Methods FTIR spectra of 51 staphylococcal isolates from AK, SCC and perilesional skin were acquired by both attenuated total reflectance (ATR)-FTIR and transflection-FTIR spectroscopy. All isolates had been previously characterized by 16S rRNA sequencing. ATR- and transflection-FTIR spectra were recorded in triplicate from isolated colonies taken from the same agar plate. Identification of the bacteria was based on the similarities of their spectra with those in ATR- and transflection-FTIR spectral databases originating from the Canadian lab. Results Among the 51 staphylococcal isolates included in this study, identification of S. aureus (n = 24) with 100% specificity and 100% sensitivity was achieved by both ATR- and transflection-FTIR spectroscopy. Overall, FTIR-based species identification was in 90.2% concordance with 16S rRNA sequencing. Conclusion This cross-lab study demonstrates the applicability of Canadian isolate-based ATR- and transflection-FTIR spectral databases for the identification of clinical staphylococcal isolates obtained in Australia. The results support the potential utility of FTIR spectroscopic techniques to monitor skin S. aureus colonization on AK lesions. Disclosures All authors: No reported disclosures.

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3

Greve, Tanja M., Kristine B. Andersen, and Ole F. Nielsen. "ATR-FTIR, FT-NIR and near-FT-Raman spectroscopic studies of molecular composition in human skinin vivoand pig ear skinin vitro." Spectroscopy 22, no. 6 (2008): 437–57. http://dx.doi.org/10.1155/2008/969217.

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ATR-FTIR, FT-NIR and near-FT-Raman spectroscopy were used to characterize the molecular composition of human skinin vivoand pig ear skinin vitro. Due to different measurement depths the spectroscopic techniques reveal the characteristics of different layers of the skin. Tape stripping was used with the ATR-FTIR technique. Spectral differences concerning lipid content and conformation, protein secondary structure or content of water were found with respect to both gender and species (i.e. human versus pig ear) at all measured skin depths. New assignments of so far unassigned lipid and protein peaks in the FT-NIR and ATR-FTIR spectra of skin were made. PCA and PLS models were used to investigate the division of the recorded spectra into groups. With respect to classification of male and female subjects, the PLS discriminant analysis provided a classification accuracy of 64–93% based on the ATR-FTIR spectra and 83–89% based on the Raman spectra. With respect to classification of human skinin vivoand pig ear skinin vitro, the PLS discriminant analysis provided a classification accuracy of 75–100% based on the Raman spectra and 100% based on the ATR-FTIR spectra.

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4

Pouchaname, V., R. Madivanane, and A. Tinabaye. "FTIR, FTR Spectral Analysis and DFT Calculations of 1, 8-Dimethyl Naphthalene." Advanced Materials Research 584 (October 2012): 371–75. http://dx.doi.org/10.4028/www.scientific.net/amr.584.371.

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ABSTRACT. Solid phase FTIR and FT-Raman spectra of 1, 8-dimethylnaphthalene have been recorded in the region 3700-50 cm-1. The spectra were interpreted with aid of normal coordinate analysis based on DFT using standard B3LYP/6-31G basis sets. After scaling there is good agreement between observed and calculated frequencies. Comparison of the simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes.

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KIRKWOOD, JONAH, ANDREW GHETLER, JACQUELINE SEDMAN, DANIEL LECLAIR, FRANCO PAGOTTO, JOHN W. AUSTIN, and ASHRAF A. ISMAIL. "Differentiation of Group I and Group II Strains of Clostridium botulinum by Focal Plane Array Fourier Transform Infrared Spectroscopy." Journal of Food Protection 69, no. 10 (October 1, 2006): 2377–83. http://dx.doi.org/10.4315/0362-028x-69.10.2377.

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A method was developed for whole-organism fingerprinting of Clostridium botulinum isolates by focal plane array Fourier transform infrared (FPA-FTIR) spectroscopy. A database of 150,000 infrared spectra of 44 strains of C. botulinum was acquired using a FPA-FTIR imaging spectrometer equipped with a 16 × 16 array detector to evaluate the ability of FTIR spectroscopy to differentiate the 44 strains. The database contained strains from C. botulinum groups I and II producing botulinum neurotoxin of serotypes A, B, E, and F. All strains were grown on each of three agar media (brain heart infusion, McClung Toabe agar base, and universal) prior to spectral acquisition. Given the dependence of the infrared spectra of microorganisms on the composition of the growth medium, the spectra were initially separated into three subsets corresponding to the three growth media employed. However, the replicate spectra of all strains, regardless of growth medium, were properly clustered by hierarchical cluster analysis based on differences in their infrared spectral profiles in three narrow spectral regions (1,428 to 1,412, 1,296 to 1,284, and 1,112 to 1,100 cm−1). The dendrogram generated from the FTIR data revealed complete separation between group I and group II strains. The spectral differences between group I and group II strains allowed accurate classification of C. botulinum strains at the group level in two blind validation studies (n = 40). These results demonstrate that FPA-FTIR spectroscopy has the potential for rapid discrimination of group I and group II C. botulinum strains in less than 3 min per sample.

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6

Lasalvia, Maria, Vito Capozzi, and Giuseppe Perna. "Discrimination of Different Breast Cell Lines on Glass Substrate by Means of Fourier Transform Infrared Spectroscopy." Sensors 21, no. 21 (October 21, 2021): 6992. http://dx.doi.org/10.3390/s21216992.

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Fourier transform infrared (FTIR) micro-spectroscopy has been attracting the interest of many cytologists and histopathologists for several years. This is related to the possibility of FTIR translation in the clinical diagnostic field. In fact, FTIR spectra are able to detect changes in biochemical cellular components occurring when the cells pass to a pathological state. Recently, this interest has increased because it has been shown that FTIR spectra carried out just in the high wavenumber spectral range (2500–4000 cm−1), where information mainly relating to lipids and proteins can be obtained, are able to discriminate cell lines related to different tissues. This possibility allows to perform IR absorption measurements of cellular samples deposited onto microscopy glass slides (widely used in the medical environment) which are transparent to IR radiation only for wavenumber values larger than 2000 cm−1. For these reasons, we show that FTIR spectra in the 2800–3000 cm−1 spectral range can discriminate three different cell lines from breast tissue: a non-malignant cell line (MCF10A), a non-metastatic adenocarcinoma cell line (MCF7) and a metastatic adenocarcinoma cell line (MDA). All the cells were grown onto glass slides. The spectra were discriminated by means of a principal component analysis, according to the PC1 component, whose values have the opposite sign in the pairwise score plots. This result supports the wide studies that are being carried out to promote the translation of the FTIR technique in medical practice, as a complementary diagnostic tool.

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7

Riyanta, A. B., S. Riyanto, E. Lukitaningsih, and Abdul Rohman. "The employment of Fourier Transform Infrared Spectroscopy (FTIR) and chemometrics for analysis of candlenut oil in binary mixture with grape seed oil." Food Research 4, no. 1 (September 11, 2019): 184–90. http://dx.doi.org/10.26656/fr.2017.4(1).279.

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Candlenut oil (CDO) is the target of adulteration with other plant oils to get economical profits, therefore, reliable analytical techniques should be developed. Based on the principal component analysis (PCA), grape seed oil (GSO) has the close similarity with CDO. Therefore, this study was intended to make modelling in the authentication analysis of CDO from GSO using Fourier transformed infrared (FTIR) spectroscopy in combination with chemometrics of partial least square calibration (PLSR) and discriminant analysis (DA). FTIR spectra of CDO, GSO and its binary mixtures were subjected to FTIR spectral measurement at wavenumbers of 4000-650 cm-1 , and its absorbances were used for modelling of PLSR and DA. FTIR spectra were also subjected to pre-processing including Savitzy-Golay derivatization. The optimization results showed that FTIR spectra using second derivative at the combined wavenumbers of 3000-2800 and 1600-650 cm-1 offered the optimum models. The coefficient determination (R2 ) for the relationship between actual values and FTIR predicted values was 0.9996 and 0.9975 in calibration and internal validation (prediction) models, respectively. The errors in calibration and validation were relatively low, i.e. 0.84% and 2.19 %vol/vol, respectively. Using the same FTIR spectra, DA could discriminate pure CDO and that mixed with GSO at concentration range of 1-50%vol/vol. The combination of FTIR spectroscopy and chemometrics offered effective tools for the quantification and discrimination of CDO mixed with GSO with the main advantage of its simplicity and rapidity.

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8

Ilchenko, Oleksii O., Andrii M. Kutsyk, and Vyacheslav V. Obukhovsky. "Study of Complexation in Acetone-Chloroform Mixtures by Infrared Spectroscopy." Journal of Atomic and Molecular Physics 2014 (February 24, 2014): 1–6. http://dx.doi.org/10.1155/2014/106178.

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FTIR spectra of acetone-chloroform system with various component ratios were investigated within the spectral range 3950–4550 cm−1. Methods of multivariate curve resolution were applied to decompose the FTIR spectra into specific components of different composition. A method of decomposition based on structural model of solution which contains acetone, chloroform, and complex acetone/chloroform (1 : 1) was proposed. Results of both approaches are in good agreement within the range of measuring error.

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9

Gopinath, D., and S. Gunasekaran. "The FTIR Spectra of Raw Magnesite and Sintered Magnesite." International Journal of Trend in Scientific Research and Development Volume-2, Issue-4 (June 30, 2018): 1072–76. http://dx.doi.org/10.31142/ijtsrd14224.

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10

Huleihel, Mahmoud, Marina Talyshinsky, and Vitaly Erukhimovitch. "FTIR microscopy as a method for detection of retrovirally transformed cells." Spectroscopy 15, no. 2 (2001): 57–64. http://dx.doi.org/10.1155/2001/256362.

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Fourier transform infrared (FTIR) spectroscopy is a unique technique that has potential for the optical diagnosis of cellular variations based on the characteristic molecular vibrational spectra of the cells. In the present study, a refinement of this technique − FTIR microscopy − was used in a mouse model to investigate spectral differences between primary cells and malignant cells transformed by murine sarcoma virus (MuSV). The advantage of FTIR microscopy is that it facilitates inspection of a restricted region of cell growth on a slide. A significant decrease in the intensities of the spectra was seen in malignant cells transformed by MuSV compared to primary normal cells. Also, there was a significant shift in the PO2−symmetric stretching mode from 1082 cm−1for normal cells to 1086 cm−1for malignant cells. Detectable and consistent differences between normal primary and malignant cells were evident in the shapes and positions of a number of peaks in the FTIR spectra. Our results indicated that FTIR microscopy has potential as a diagnostic method for the detection of malignant cells.

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11

Irnawati, R. N. Putri, L. A. Lestari, and A. Rohman. "Quantitative analysis and discrimination of lard in chicken fat using FTIR spectroscopy and chemometrics for halal authentication." Food Research 6, no. 4 (July 26, 2022): 211–17. http://dx.doi.org/10.26656/fr.2017.6(4).459.

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Lard (LD) has a similarity with chicken fat (CF) in terms of physicochemical characteristics especially fatty acid composition and FTIR spectra, therefore, analysis of lard in a binary mixture with CF is challenging. This study aimed to employ FTIR spectra in normal and derivative modes in combination with multivariate calibrations for quantitative analysis of LD and CF in the binary mixture and to discriminate pure LD and LD in the mixture with CF using discriminant analysis (DA). LD and CF were prepared randomly at a certain concentration to be used as calibration and validation sets, respectively. All mixtures were scanned using an FTIR spectrophotometer at 4000-650 cm -1 in absorbance mode. Some wavenumbers, FTIR spectral modes and multivariate calibrations were optimized to provide high accuracy and precision as indicated by the high value of coefficient determination (R2 ) and low values of errors in calibration and validation. The results revealed that FTIR spectra using normal spectra at combined wavenumbers of 3100-2750 and 1500-660 cm-1 with R2 for the relationship between actual and FTIR predicted values of > 0.99 in calibration and validation with an error in calibration of 0.008% and error validation of 0.032%. DA could discriminate LD and LD in the mixture with CF with an accuracy level of 100%. FTIR spectroscopy in combination with chemometrics offered a reliable method for quantitative analysis and discrimination of LD in a binary mixture with CF.

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12

Prabowo, Sulistyo, Muflihah ., and Abdul Rohman. "MONITORING OXIDATIVE LEVELS OF FRYING OILS USING FTIR SPECTROSCOPY AND MULTIVARIATE CALIBRATION." International Journal of Applied Pharmaceutics 10, no. 6 (November 22, 2018): 82. http://dx.doi.org/10.22159/ijap.2018v10i6.29716.

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Objective: To develop a rapid reliable technique based on Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectroscopy in combination with multivariate calibrations for prediction of frying oil quality, namely acid value (AV), iodine value (IV) and peroxide value (PV).Methods: FTIR spectra were directly obtained and subjected to optimization and spectral treatments including a selection of wavenumbers region and spectral derivatization. The condition selected was based on its capability to provide the highest coefficient of determination (R2) and the lowest root mean square error of calibration (RMSEC) and root mean square error of prediction (RMSEP) for the relationship between actual values of AV, IV, and PV as determined using standard titrimetric methods and predicted values as determined by FTIR spectroscopy aided with multivariate calibrations.Results: Using optimized condition, FTIR spectroscopy combined with multivariate calibrations could be successfully used for prediction of AV, and PV. Acid value (AV) could be determined using the first derivative spectra at wavenumbers of 1524-658 cm-1. The R2of 0.973 (in calibration model) and 0.932 (in prediction model) with low RMSEC and RMSEP values was obtained. Iodine value (IV) was best predicted using principle component regression (PCR) with normal FTIR spectra at the combined wavenumbers region of 3076-2783 and 1811-656 cm-1. PCR using normal spectra at combined wavenumbers region of 3076-2783and 1811-656 cm-1 was also selected for prediction of PV. Conclusion: FTIR spectroscopy in combination with multivariate calibration has been successfully used for prediction of acid value, iodine value and peroxide value in frying oils. The developed method could be an alternative technique for analysis of these values to perform quality assurance of frying oils.

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13

TAKANAKA, Tohru. "FTIR spectra of langmuir-blodgett films." Journal of the Spectroscopical Society of Japan 35, no. 4 (1986): 323–25. http://dx.doi.org/10.5111/bunkou.35.323.

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14

Quickenden, T. I., and M. J. Comarmond. "FTIR Spectra of Thionine‐Modified Electrodes." Journal of The Electrochemical Society 135, no. 4 (April 1, 1988): 918–20. http://dx.doi.org/10.1149/1.2095833.

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15

Ramis, Gianguido, and Guido Busca. "FTIR spectra of adsorbed n-butylamine." Journal of Molecular Structure 193 (February 1989): 93–100. http://dx.doi.org/10.1016/0022-2860(89)80124-3.

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16

Friesen, W. I., and K. H. Michaelian. "Fourier deconvolution of photoacoustic FTIR spectra." Infrared Physics 26, no. 4 (July 1986): 235–42. http://dx.doi.org/10.1016/0020-0891(86)90075-8.

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17

Missailidis, S., and R. E. Hester. "FTIR spectra of deoxyoligonucleotide-nogalamycin complexes." Biospectroscopy 1, no. 2 (1995): 91–99. http://dx.doi.org/10.1002/bspy.350010202.

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18

Dziuba, B. "Identification of Propionibacteria to the species level using Fourier transform infrared spectroscopy and artificial neural networks." Polish Journal of Veterinary Sciences 16, no. 2 (June 1, 2013): 351–57. http://dx.doi.org/10.2478/pjvs-2013-0047.

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Abstract Fourier transform infrared spectroscopy (FTIR) and artificial neural networks (ANN’s) were used to identify species of Propionibacteria strains. The aim of the study was to improve the methodology to identify species of Propionibacteria strains, in which the differentiation index D, calculated based on Pearson’s correlation and cluster analyses were used to describe the correlation between the Fourier transform infrared spectra and bacteria as molecular systems brought unsatisfactory results. More advanced statistical methods of identification of the FTIR spectra with application of artificial neural networks (ANN’s) were used. In this experiment, the FTIR spectra of Propionibacteria strains stored in the library were used to develop artificial neural networks for their identification. Several multilayer perceptrons (MLP) and probabilistic neural networks (PNN) were tested. The practical value of selected artificial neural networks was assessed based on identification results of spectra of 9 reference strains and 28 isolates. To verify results of isolates identification, the PCR based method with the pairs of species-specific primers was used. The use of artificial neural networks in FTIR spectral analyses as the most advanced chemometric method supported correct identification of 93% bacteria of the genus Propionibacterium to the species level.

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Tkachenko, Yana, and Przemysław Niedzielski. "FTIR as a Method for Qualitative Assessment of Solid Samples in Geochemical Research: A Review." Molecules 27, no. 24 (December 13, 2022): 8846. http://dx.doi.org/10.3390/molecules27248846.

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This study aims to collect information about soil investigation by FTIR. As we know, the FTIR technique is most often used in organic and bioorganic chemistry, while in geochemistry FTIR spectroscopy is not used very often. Therefore, there is a problem with the identification and interpretation of the IR spectra of minerals contained in sediments and soils. The reason for this is a deficiency of data about characteristic wavenumbers for minerals. Therefore, this study reviews and sums up, in one place, published articles that are connected to an investigation of minerals from 2002 to 2021 (based on the Scopus database). Additionally, the present review highlights various analytical techniques (ATR-FTIR, DRIFT, 2D-IR, and SR-FTIR) and discusses some of them for geochemical study. Additionally, the study describes helpful tools in the data pre-processing of IR spectra (normalization, baseline correction, and spectral derivatives).

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Osman, Salma O. M., Abu Sefyan I. Saad, Shota Tadano, Yoshiki Takeda, Yuji Yamasaki, Izzat S. A. Tahir, Hisashi Tsujimoto, and Kinya Akashi. "Probing Differential Metabolome Responses among Wheat Genotypes to Heat Stress Using Fourier Transform Infrared-Based Chemical Fingerprinting." Agriculture 12, no. 6 (May 25, 2022): 753. http://dx.doi.org/10.3390/agriculture12060753.

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Heat stress is one of the major environmental constraints for wheat production; thus, a comprehensive understanding of the metabolomic responses of wheat is required for breeding heat-tolerant varieties. In this study, the metabolome responses of heat-tolerant genotypes Imam and Norin 61, and susceptible genotype Chinese Spring were comparatively analyzed using Fourier transform infrared (FTIR) spectroscopy in combination with chemometric data mining techniques. Principal component analysis of the FTIR data suggested a spectral feature partially overlapping between the three genotypes. FTIR spectral biomarker assay showed similar heat responses between the genotypes for markers Fm482 and Fm1502, whereas genotype-dependent variations were observed for other markers. The markers Fm1251 and Fm1729 showed contrasting behaviors between heat-tolerant and susceptible genotypes, suggesting that these markers may potentially serve as a tool for distinguishing heat-tolerant genotypes. Linear discriminant analysis (LDA) of the spectra demonstrated a clear separation between the three genotypes in terms of the heat stress effect. Analysis of LDA coefficients identified several spectral regions that were potentially responsible for the discrimination of FTIR spectra between different genotypes and environments. These results suggest that a combination of FTIR and chemometrics can be a useful technique for characterizing the metabolic behavior of diverse wheat genotypes under heat stress.

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Araújo, Rúben, Luís Ramalhete, Edna Ribeiro, and Cecília Calado. "Plasma versus Serum Analysis by FTIR Spectroscopy to Capture the Human Physiological State." BioTech 11, no. 4 (December 9, 2022): 56. http://dx.doi.org/10.3390/biotech11040056.

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Fourier Transform InfraRed spectroscopy of serum and plasma has been highly explored for medical diagnosis, due to its general simplicity, and high sensitivity and specificity. To evaluate the plasma and serum molecular fingerprint, as obtained by FTIR spectroscopy, to acquire the system metabolic state, serum and plasma spectra were compared to characterize the metabolic state of 30 human volunteers, between 90 days consumption of green tea extract rich in Epigallocatechin-3-gallate (EGCG). Both plasma and serum spectra enabled the high impact of EGCG consumption on the biofluid spectra to be observed, as analyzed by the spectra principal component analysis, hierarchical-cluster analysis, and univariate data analysis. Plasma spectra resulted in the prediction of EGCG consumption with a slightly higher specificity, accuracy, and precision, also pointing to a higher number of significant spectral bands that were different between the 90 days period. Despite this, the lipid regions of the serum spectra were more affected by EGCG consumption than the corresponding plasma spectra. Therefore, in general, if no specific compound analysis is highlighted, plasma is in general the advised biofluid to capture by FTIR spectroscopy the general metabolic state. If the lipid content of the biofluid is relevant, serum spectra could present some advantages over plasma spectra.

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Pilling, Michael J., Paul Bassan, and Peter Gardner. "Comparison of transmission and transflectance mode FTIR imaging of biological tissue." Analyst 140, no. 7 (2015): 2383–92. http://dx.doi.org/10.1039/c4an01975j.

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Lin, Cheng-Hsien, Richard H. Grant, Albert J. Heber, and Cliff T. Johnston. "Application of open-path Fourier transform infrared spectroscopy (OP-FTIR) to measure greenhouse gas concentrations from agricultural fields." Atmospheric Measurement Techniques 12, no. 6 (June 27, 2019): 3403–15. http://dx.doi.org/10.5194/amt-12-3403-2019.

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Abstract. Open-path Fourier transform infrared spectroscopy (OP-FTIR) has often been used to measure hazardous or trace gases from hot point sources (e.g. volcano, industrial, or agricultural facilities) but seldom used to measure greenhouse gases (GHGs) from field-scale sources (e.g. agricultural soils). Closed-path mid-IR laser-based N2O, nondispersive-IR CO2 analysers, and OP-FTIR were used to measure concentrations of N2O and CO2 at a maize cropping system during 9–19 June 2014. To measure N2O and CO2 concentrations accurately, we developed a quantitative method of N2O∕CO2 analysis that minimized interferences from diurnal changes of humidity and temperature. Two chemometric multivariate models, classical least squares (CLS) and partial least squares (PLS), were developed. This study evaluated various methods to generate the single-beam background spectra and different spectral regions for determining N2O and CO2 concentrations from OP-FTIR spectra. A standard extractive method was used to measure the actual path-averaged concentrations along an OP-FTIR optical path in situ, as a benchmark to assess the feasibilities of these quantitative methods. Within an absolute humidity range of 5000–20 000 ppmv and a temperature range of 10–35 ∘C, we found that the CLS model underestimated N2O concentrations (bias =-4.9±3.1 %) calculated from OP-FTIR spectra, and the PLS model improved the accuracy of calculated N2O concentrations (bias =1.4±2.3 %). The bias of calculated CO2 concentrations was -1.0±2.8 % using the CLS model. These methods suggested that environmental variables potentially lead to biases in N2O and CO2 estimations from OP-FTIR spectra and may help OP-FTIR users avoid dependency on extractive methods of calibrations.

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Ibrahim, Amr, Adriana Predoi-Cross, and Chad Povey. "Handling techniques for channel spectra in synchrotron-based Fourier transform spectra." Canadian Journal of Physics 91, no. 11 (November 2013): 910–23. http://dx.doi.org/10.1139/cjp-2013-0050.

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Recently, the high radiance of synchrotron sources has been used to enhance FTIR spectrometer performance. However, excessive channel spectra when synchrotron sources are used degrade the quality of retrieved spectral parameters. We have investigated seven different techniques for handling channel spectra. These techniques were used to reduce channel spectra for a test group of seven samples of CO2 mixed with air recorded using the synchrotron source at the Canadian Light Source. The increases in signal to noise ratio (SNR) of spectra handled with each technique were calculated. SNR results showed that transmission spectra, produced using synthetic background spectra with simulated channel spectra, achieved the highest SNR improvement. However, when the spectra groups were fitted using a nonlinear least square fit algorithm, the technique using channel spectra fitting produced the smallest fitting residual. Moreover, the retrieved intensities and air broadening coefficients of 21 spectral lines showed that the spectral fitting technique produced the most accurate values as compared to the HITRAN 2008 database (Rothman et al. J. Quant. Spectrosc. Radiat. Transfer, 110, 533 (2009)). Although the spectral fitting technique was accurate in retrieving spectral line parameters, applying the technique at wider spectral ranges reduced this accuracy.

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Lam, Lisa M. T., Ashraf Ismail, Jacqueline Sedman, and Émilie Vallières. "2167. Evaluation of Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy for Rapid and Reagent-Free Identification of Burkholderia spp." Open Forum Infectious Diseases 6, Supplement_2 (October 2019): S735. http://dx.doi.org/10.1093/ofid/ofz360.1847.

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Abstract Background Burkholderia cepacia complex including B. gladioli are opportunistic pathogenic bacteria affecting the immunocompromised population. For prognosis and appropriate treatment, rapid and accurate species identification is particularly important for those diagnosed with cystic fibrosis (CF). Conventional biochemical identification techniques are insensitive and problematic for identifying Burkholderia spp., leading to common misidentification or inconclusive results. Recent studies have successfully employed attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy for rapid, reagent-free and cost-effective microbial identification. In the present study, identification of Burkholderia spp. by this technique is investigated. Methods A total of 59 isolates belonging to 7 species of Burkholderia were included in this study; all these isolates had been well-characterized by VITEK 2, 16S rRNA sequencing, random amplification of polymorphic DNA (recA typing) and/or matrix-assisted laser desorption/ionization time of flight mass spectrometry. ATR-FTIR spectra were acquired directly from colonies on 5% blood agar plates. Results A spectral database containing ATR-FTIR spectra of over 4300 bacterial isolates, encompassing over 70 genera and 190 species, was updated to include spectra of 39 isolates collected in this study and employed in the identification of the other isolates (n = 20). All isolates were correctly identified as Burkholderia by a multitier search approach. For Burkholderia species identification, spectra belonging to 39 isolates representative of all 7 species were used to construct a spectral database employed to identify the other 20 isolates [B. anthina (n = 2), B. gladioli (n = 8), B. multivorans (n = 7), and B. vietnamiensis (n = 3)]. Compared with VITEK 2 (30% correct species identification), ATR-FTIR spectroscopy correctly identified all but one isolate, resulting in overall correct species identification of 95%. Prospectively (10 months), 5 of 1100 isolates collected were identified as Burkholderia spp. by ATR-FTIR spectroscopy in concordance with VITEK 2. Conclusion ATR-FTIR spectroscopy can provide the means of rapid Burkholderia spp. identification for appropriate treatment of those diagnosed with CF. Disclosures All authors: No reported disclosures.

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Vazquez-Zapien, Gustavo Jesus, Monica Maribel Mata-Miranda, Virginia Sanchez-Monroy, Raul Jacobo Delgado-Macuil, David Guillermo Perez-Ishiwara, and Marlon Rojas-Lopez. "FTIR Spectroscopic and Molecular Analysis during Differentiation of Pluripotent Stem Cells to Pancreatic Cells." Stem Cells International 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/6709714.

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Some of the greatest challenges in stem cells (SCs) biology and regenerative medicine are differentiation control of SCs and ensuring the purity of differentiated cells. In this work, we differentiated mouse pluripotent stem cells (mPSCs) toward pancreatic cells characterizing this differentiation process by molecular and spectroscopic technics. Both mPSCs and Differentiated Pancreatic Cells (DPCs) were subjected to a genetic, phenotypic, and biochemical analysis by real-time quantitative PCR (RT-qPCR), immunocytochemistry, and Fourier Transform Infrared (FTIR) spectroscopy. Cultured mPCSs expressed pluripotent genes and proteins (NanogandSOX2). DPCs expressed endodermal genes (SOX17andPdx1) at day 11, an inductor gene of embryonic pancreas development (Pdx1) at day 17 and pancreas genes and proteins (InsulinandGlucagon) at day 21 of differentiation. Likewise, FTIR spectra of mPSCs and DPCs at different maturation stages (11, 17, and 21 days) were obtained and showed absorption bands related with different types of biomolecules. These FTIR spectra exhibited significant spectral changes agreeing with the differentiation process, particularly in proteins and nucleic acids bands. In conclusion, the obtained DPCs passed through the chronological stages of embryonic pancreas development and FTIR spectra provide a new biophysical parameter based on molecular markers indicating the differentiation process of mPSCs to specialized cells.

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Sarvjeet Dubey, Raghvendra, and Sigamani Saravanan. "OPTICAL STUDY OF SOL-GEL SPIN-COATING TiO2/Si3N4 MULTILAYERS ON GLASS SUBSTRATES." RASAYAN Journal of Chemistry 15, no. 04 (2022): 2304–9. http://dx.doi.org/10.31788/rjc.2022.1547077.

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In this work, we have adopted a sol-gel spin-coating technique and prepared alternative TiO2/Si3N4 multilayers on glass substrates. These alternating layers of TiO2/Si3N4 thin film samples were calcinated at two different temperatures and studied for their optical performance. The optical properties of fabricated thin films were investigated by UV-Visible spectrophotometer, X-ray diffractometer (XRD), Fourier transform infrared (FTIR), and Raman spectroscopy. UV-visible spectra showed broader and higher optical reflectance in the visible spectral region. FTIR transmission spectra show Ti-O-Ti and Si-N stretching modes at around 600 and 881 cm-1. XRD pattern confirmed the presence of anatase-TiO2 and α-Si3N4 phases. Finally, Raman spectra revealed the presence of anatase-TiO2 and N-Si vibration modes.

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Rahman, Ubaid ur, Amna Sahar, Imran Pasha, Sajjad ur Rahman, and Anum Ishaq. "Assessing the capability of Fourier transform infrared spectroscopy in tandem with chemometric analysis for predicting poultry meat spoilage." PeerJ 6 (August 6, 2018): e5376. http://dx.doi.org/10.7717/peerj.5376.

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Background Use of traditional methods for determining meat spoilage is quite laborious and time consuming. Therefore, alternative approaches are needed that can predict the spoilage of meat in a rapid, non-invasive and more elaborative way. In this regard, the spectroscopic techniques have shown their potential for predicting the microbial spoilage of meat-based products. Consequently, the present work was aimed to demonstrate the competence of Fourier transform infrared spectroscopy (FTIR) to detect spoilage in chicken fillets stored under aerobic refrigerated conditions. Methods This study was conducted under controlled randomized design (CRD). Chicken samples were stored for 8 days at 4 + 0.5 °C and FTIR spectra were collected at regular intervals (after every 2 days) directly from the sample surface using attenuated total reflectance during the study period. Additionally, total plate count (TPC), Entetobacteriaceae count, pH, CTn (Color transmittance number) color analysis, TVBN (total volatile basic nitrogen) contents, and shear force values were also measured through traditional approaches. FTIR spectral data were interpreted through principal component analysis (PCA) and partial least square (PLS) regression and compared with results of traditional methods for precise estimation of spoilage. Results Results of TPC (3.04–8.20 CFU/cm2), Entetobacteriaceae counts (2.39–6.33 CFU/cm2), pH (4.65–7.05), color (57.00–142.00 CTn), TVBN values (6.72–33.60 mg/100 g) and shear force values (8.99–39.23) were measured through traditional methods and compared with FTIR spectral data. Analysis of variance (ANOVA) was applied on data obtained through microbial and quality analyses and results revealed significant changes (P < 0.05) in the values of microbial load and quality parameters of chicken fillets during the storage. FTIR spectra were collected and PCA was applied to illuminate the wavenumbers potentially correlated to the spoilage of meat. PLS regression analysis permitted the estimates of microbial spoilage and quality parameters from the spectra with a fit of R2 = 0.66 for TPC, R2 = 0.52 for Entetobacteriaceae numbers and R2 = 0.56 for TVBN analysis of stored broiler meat. Discussion PLS regression was applied for quantitative interpretation of spectra, which allowed estimates of microbial loads on chicken surfaces during the storage period. The results suggest that FTIR spectra retain information regarding the spoilage of poultry meat. Conclusion The present work concluded that FTIR spectroscopy coupled with multivariate analysis can be successfully used for quantitative determination of poultry meat spoilage.

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Perna, Giuseppe, Vito Capozzi, and Maria Lasalvia. "Classification of Healthy and Cancer Colon Cells Grown on Glass Coverslip by Means of Fourier Transform Infrared Spectroscopy and Multivariate Methods." Photonics 10, no. 4 (April 21, 2023): 481. http://dx.doi.org/10.3390/photonics10040481.

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For several years, Fourier transform infrared (FTIR) microspectroscopy has been proving to be very promising for use in cytological diagnostics because of its capability of providing rapid and label-free biochemical information about cell samples. The adoption of FTIR as a clinical tool has been slowed because of the poor compatibility with cells deposited on glass slides, commonly used in clinical practice, because of the absorption of IR radiation by glassy materials in the 1000–1800 cm−1 spectral range. However, the possibility of also obtaining diagnostic information from the IR absorption spectra in the 2700–3700 cm−1 range (including few peaks related to vibrational modes in cell lipids and proteins) has recently emerged. In this work, we investigate the use of the FTIR technique in the 2700–3700 cm−1 range for diagnostic purposes about human colon cells grown on glass coverslips. In fact, using the principal components analysis (PCA) technique, we are able to discriminate FTIR spectra of healthy cells from those of cancerous ones, mainly due to the larger relative lipid content in the former compared to the latter. In addition, principal component analysis-linear discriminate analysis (PCA-LDA) and partial least square-discriminant analysis (PLS-DA) were used to build classification models for unknown FTIR spectra with optimal accuracy. These results support the promotion of the translation of the FTIR technique as a complementary diagnostic tool in cytological routine practice.

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Magazù, S., E. Calabrò, and M. T. Caccamo. "Experimental Study of Thermal Restraint in Bio-Protectant Disaccharides by FTIR Spectroscopy." Open Biotechnology Journal 12, no. 1 (July 31, 2018): 123–33. http://dx.doi.org/10.2174/1874070701812010123.

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Background: In the present paper, InfraRed (IR) spectra on water mixtures of two homologous disaccharides, i.e. sucrose and trehalose, as a function of temperature have been collected. Methods: In particular, IR spectra were registered, in the spectral range from 4000 cm-1 to 400 cm-1, to investigate the thermal response of the water mixtures of two homologous disaccharides, through positive thermal scans, i.e. by increasing the temperature from the value of 25°C to the value of 50°C. The OH-stretching region has been analyzed by means of two simple and straightforward procedures, i.e. by evaluating the shift of the intramolecular OH stretching center frequency and the Spectral Distance (SD). Result and Conclusion: Both the analyses indicate that trehalose water mixture have a higher thermal response than that of the sucrose-water mixture.

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Chen, Cong Jin, Jian Ju Luo, Xiu Ping Huang, and Shu Kai Zhao. "Analysis on Cellulose Crystalline and FTIR Spectra of Artocarpus heterophyllus Lam Wood and Its Main Chemical Compositions." Advanced Materials Research 236-238 (May 2011): 369–75. http://dx.doi.org/10.4028/www.scientific.net/amr.236-238.369.

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Cellulose crystalline and FTIR spectra ofArtocarpus heterophyllusLam wood and its main chemical compositions were analyzed.The result showed that the FTIR spectra of original wood samples fromArtocarpus heterophyllusLam wood present the same basic structure of all wood samples, the FTIR spectra of extracted wood samples were compared with the original wood sample, some of their absorption peaks of the band shifted to long or short wave, the wood and the solvent had little chemical reaction in the extracting process. FTIR spectra crystalline index of nitric acid-ethanol cellulose fromArtocarpus heterophyllusLam wood is NO′KI10.984, O′KI21.59, X-ray diffraction crystalline index of nitric acid-ethanol cellulose fromArtocarpus heterophyllusLam wood is 0.794.

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Amarie, Sergiu, Paul Zaslansky, Yusuke Kajihara, Erika Griesshaber, Wolfgang W. Schmahl, and Fritz Keilmann. "Nano-FTIR chemical mapping of minerals in biological materials." Beilstein Journal of Nanotechnology 3 (April 5, 2012): 312–23. http://dx.doi.org/10.3762/bjnano.3.35.

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Methods for imaging of nanocomposites based on X-ray, electron, tunneling or force microscopy provide information about the shapes of nanoparticles; however, all of these methods fail on chemical recognition. Neither do they allow local identification of mineral type. We demonstrate that infrared near-field microscopy solves these requirements at 20 nm spatial resolution, highlighting, in its first application to natural nanostructures, the mineral particles in shell and bone. "Nano-FTIR" spectral images result from Fourier-transform infrared (FTIR) spectroscopy combined with scattering scanning near-field optical microscopy (s-SNOM). On polished sections of Mytilus edulis shells we observe a reproducible vibrational (phonon) resonance within all biocalcite microcrystals, and distinctly different spectra on bioaragonite. Surprisingly, we discover sparse, previously unknown, 20 nm thin nanoparticles with distinctly different spectra that are characteristic of crystalline phosphate. Multicomponent phosphate bands are observed on human tooth sections. These spectra vary characteristically near tubuli in dentin, proving a chemical or structural variation of the apatite nanocrystals. The infrared band strength correlates with the mineral density determined by electron microscopy. Since nano-FTIR sensitively responds to structural disorder it is well suited for the study of biomineral formation and aging. Generally, nano-FTIR is suitable for the analysis and identification of composite materials in any discipline, from testing during nanofabrication to even the clinical investigation of osteopathies.

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Wilcox, C. F., and S. H. Bauer. "The FTIR spectra of CH3CH2Br and CD3CH2Br." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 52, no. 2 (February 1996): 207–12. http://dx.doi.org/10.1016/0584-8539(95)01546-9.

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Werheit, H., and U. Kuhlmann. "FTIR and FT Raman Spectra of B6O." Journal of Solid State Chemistry 133, no. 1 (October 1997): 260–63. http://dx.doi.org/10.1006/jssc.1997.7452.

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Tandel, Vanish H., I. B. Patel, S. A. Suthar, and A. M. Shah. "Influence studies of doping on FTIR Spectra and Thermogravimetric Analysis of Barium Nitrate Crystals." Material Science Research India 15, no. 1 (February 5, 2018): 83–90. http://dx.doi.org/10.13005/msri/150110.

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Pure and Magnesium Nitrate hexahydrate (MgN) doped Barium Nitrate (BaN) crystals were grown by slow evaporation technique. FTIR spectral studies have been carried to identify the presence various functional groups. An FTIR spectrum of grown crystals confirms the presence of ionic bonds in the structure of pure and doped BaN crystals. The influence of MgN doping on FTIR spectra was absorbing frequencies by pure and doped BaN crystals were studied. Thermogravimetric of pure and doped BaN crystals were analysed to characterise thermal stability. Thermal parameters are evaluated using thermogram. The results are presented and discussed in this paper.

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Ju, Wei, Changhua Lu, Chun Liu, Weiwei Jiang, Yujun Zhang, and Feng Hong. "Rapid Identification of Atmospheric Gaseous Pollutants Using Fourier-Transform Infrared Spectroscopy Combined with Independent Component Analysis." Journal of Spectroscopy 2020 (January 22, 2020): 1–14. http://dx.doi.org/10.1155/2020/8920732.

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Fourier-transform infrared (FTIR) spectroscopy is a rapid and nondestructive technology for monitoring atmospheric quality. The identification of each component from the FTIR spectra is a prerequisite for the accurate quantitative analysis of gaseous pollutants. Due to the overlap of different gas absorption peaks and the interference of water vapor in the actual measurement, the existing identification methods of gas spectra have drawbacks of low identification rate and the inability to carry out real-time online analysis in atmospheric quality monitoring. In this work, independent component analysis (ICA) is applied to the spectral separation of heavily overlapped spectra of gaseous pollutants. The proposed method is validated by the analysis of mixture spectra obtained in laboratory and actual atmospheric spectra collected from stationary source. The average time consumption of separation process is less than 0.2 seconds, and the identification rate of experimental gases is up to 100%, as shown by the results of peak searching and the analysis of the correction coefficient between the separated spectra and the standard spectra database. The identification results of actual atmospheric spectra demonstrated that the proposed method can effectively identify the gaseous pollutants whose concentration changes in the measured spectra, and it is a promising qualitative spectral analysis tool that can shorten the identification time, as well as increase the identification rate. Therefore, this method can be a useful alternative to traditional qualitative identification methods for real-time online atmospheric pollutant detection.

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Pereira, Thiago Martini, Maria Lucia Zaidan Dagli, Grégory Mennecier, and Denise Maria Zezell. "Influence of Fixation Products Used in the Histological Processing in the FTIR Spectra of Lung Cells." Spectroscopy: An International Journal 27 (2012): 399–402. http://dx.doi.org/10.1155/2012/649094.

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The aim of the present study is to evaluate the differences on FTIR spectra of the normal lung cell (noncancerous mice lung epithelial cell line e10) due to different fixation protocols for histological processing. The results shown that formalin and methacarn (normally used in fixation) did cause many changes on the FTIR spectra of mice lung cells e10, mainly in the organic compounds (800–1800 cm−1) in lipids, DNA, and proteins, and the alcohol 70% fixation protocol caused almost no changes on the FTIR spectra compared to unfixed cells spectra (in PBS). It can be concluded that histological processing with alcohol 70% fixation protocol can be used in the FTIR study of mice lung cell line e10.

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Chaber, Radosław, Christopher Arthur, Kornelia Łach, Anna Raciborska, Elżbieta Michalak, Katarzyna Bilska, Katarzyna Drabko, Joanna Depciuch, Ewa Kaznowska, and Józef Cebulski. "Predicting Ewing Sarcoma Treatment Outcome Using Infrared Spectroscopy and Machine Learning." Molecules 24, no. 6 (March 19, 2019): 1075. http://dx.doi.org/10.3390/molecules24061075.

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Background: Improved outcome prediction is vital for the delivery of risk-adjusted, appropriate and effective care to paediatric patients with Ewing sarcoma—the second most common paediatric malignant bone tumour. Fourier transform infrared (FTIR) spectroscopy of tissues allows the bulk biochemical content of a biological sample to be probed and makes possible the study and diagnosis of disease. Methods: In this retrospective study, FTIR spectra of sections of biopsy-obtained bone tissue were recorded. Twenty-seven patients (between 5 and 20 years of age) with newly diagnosed Ewing sarcoma of bone were included in this study. The prognostic value of FTIR spectra obtained from Ewing sarcoma (ES) tumours before and after neoadjuvant chemotherapy were analysed in combination with various data-reduction and machine learning approaches. Results: Random forest and linear discriminant analysis supervised learning models were able to correctly predict patient mortality in 92% of cases using leave-one-out cross-validation. The best performing model for predicting patient relapse was a linear Support Vector Machine trained on the observed spectral changes as a result of chemotherapy treatment, which achieved 92% accuracy. Conclusion: FTIR spectra of tumour biopsy samples may predict treatment outcome in paediatric Ewing sarcoma patients with greater than 92% accuracy.

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Younis, Uzma, Ashfaq Ahmad Rahi, Subhan Danish, Muhammad Arif Ali, Niaz Ahmed, Rahul Datta, Shah Fahad, et al. "Fourier Transform Infrared Spectroscopy vibrational bands study of Spinacia oleracea and Trigonella corniculata under biochar amendment in naturally contaminated soil." PLOS ONE 16, no. 6 (June 30, 2021): e0253390. http://dx.doi.org/10.1371/journal.pone.0253390.

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Fourier transform infrared spectroscopy (FTIR) spectroscopy detects functional groups such as vibrational bands like N-H, O-H, C-H, C = O (ester, amine, ketone, aldehyde), C = C, C = N (vibrational modes of a tetrapyrrole ring) and simply C = N. The FTIR of these bands is fundamental to the investigation of the effect of biochar (BC) treatment on structural changes in the chlorophyll molecules of both plants that were tested. For this, dried leaf of Spinacia oleracia (spinach) and Trigonella corniculata (fenugreek) were selected for FTIR spectral study of chlorophyll associated functional groups. The study’s primary goal was to investigate the silent features of infrared (IR) spectra of dried leave samples. The data obtained from the current study also shows that leaf chlorophyll can mask or suppress other molecules’ FITR bands, including proteins. In addition, the C = O bands with Mg and the C9 ketonic group of chlorophyll are observed as peaks at1600 (0%BC), 1650 (3%BC) and 1640, or near to1700 (5%BC) in spinach samples. In fenugreek, additional effects are observed in the FTIR spectra of chlorophyll at the major groups of C = C, C = O and C9 of the ketonic groups, and the vibrational bands are more evident at C-H and N-H of the tetrapyrrole ring. It is concluded that C-N bands are more visible in 5% BC treated spinach and fenugreek than in all other treatments. These types of spectra are useful in detecting changes or visibility of functional groups, which are very helpful in supporting biochemical data such as an increase in protein can be detected by more visibility of C-N bands in FTIR spectra.

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Buoso, Maria Crista, Mario De Poli, Peter Matthaes, Luca Silvestrin, and Demetre Zafiropoulos. "Nondestructive wood discrimination: FTIR – Fourier Transform Infrared Spectroscopy in the characterization of different wood species used for artistic objects." International Journal of Modern Physics: Conference Series 44 (January 2016): 1660212. http://dx.doi.org/10.1142/s201019451660212x.

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Wooden artifacts represent a significant component of past cultures. Successful conservation of wooden artifacts depends on the knowledge of wood structure and types. It is critical that conservators know the category of wood that they are treating in order to successfully conserve it. Recently, vibrational spectroscopy has been successfully applied to determine the chemical structure of wood and to characterize wood types. FTIR (Fourier Transform Infrared) is a useful nondestructive or micro-destructive analytical technique providing information about chemical bonding and molecular structure. Its application in the discrimination between softwoods (conifers) and hardwoods (broad-leafs) has already been reported. The aim of the present study was to investigate the potential of FTIR as a tool for the discrimination between different wood types belonging to the same genus. Three different hardwood species, namely poplar (Populus spp), lime (Tilia spp) and birch (Betula spp), were investigated by means of FTIR spectroscopy. The woods were first inspected using a light microscope to certify the wood essence types through micrographic and morphoanatomical features. The FTIR spectra in the 4000 cm[Formula: see text] to 450 cm[Formula: see text] region were recorded using a Perkin-Elmer Spectrum 100 spectrometer. To enhance the qualitative interpretation of the IR spectra, second derivatives of all spectra were calculated using the Spectrum software to separate superimposed bands and to extract fine spectral details. To obtain a comprehensive characterization, the essences under investigation were also analyzed by means of Raman Spectroscopy. Clear differences were found in the spectra of the three samples confirming FTIR to be a powerful tool for wood type discrimination.

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Cięszczyk, Sławomir. "A Multi-Band Integrated Virtual Calibration-Inversion Method for Open Path FTIR Spectrometry." Metrology and Measurement Systems 20, no. 2 (June 1, 2013): 287–98. http://dx.doi.org/10.2478/mms-2013-0025.

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Abstract This paper addresses problems arising from in situ measurement of gas content and temperature. Such measurements can be considered indirect. Transmittance or natural radiation of a gas is measured directly. The latter method (spectral radiation measurement) is often called spectral remote sensing. Its primary uses are in astronomy and in the measurement of atmospheric composition. In industrial processes, in situ spectroscopic measurements in the plant are often made with an open path Fourier Transform Infrared (FTIR) spectrometer. The main difficulty in this approach is related to the calibration process, which often cannot be carried out in the manner used in the laboratory. Spectral information can be obtained from open path spectroscopic measurements using mathematical modeling, and by solving the inverse problem. Determination of gas content based on spectral measurements requires comparison of the measured and modeled spectra. This paper proposes a method for the simultaneous use of multiple lines to determine the gas content. The integrated absorptions of many spectral lines permits calculation of the average band absorption. An inverse model based on neural networks is used to determine gas content based on mid-infrared spectra at variable temperatures.

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Jain, Vishal, Hitesh Parmar, and Ketan Dodiya. "FTIR Spectra of Magnetic Charge Transfer Complexes of TEMPO Free Radical." International Journal of Trend in Scientific Research and Development 1, no. 2 (February 27, 2017): 8–13. http://dx.doi.org/10.31142/ijtsrd62.

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Makhnii, T., O. Ilchenko, A. Reynt, Y. Pilgun, A. Kutsyk, D. Krasnenkov, M. Ivasyuk, and V. Kukharskyy. "Age-Related Changes in FTIR and Raman Spectra of Human Blood." Ukrainian Journal of Physics 61, no. 10 (October 2016): 853–62. http://dx.doi.org/10.15407/ujpe61.10.0853.

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Karbovnyk, Ivan, P. Savchyn, Andrzej Huczko, Maruangela Cestelli Guidi, Chiara Mirri, and A. I. Popov. "FTIR Studies of Silicon Carbide 1D-Nanostructures." Materials Science Forum 821-823 (June 2015): 261–64. http://dx.doi.org/10.4028/www.scientific.net/msf.821-823.261.

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Stable 1D silicon carbide nanostructures (nanowires) have been obtained via combustion synthesis route. Infrared absorption and reflection spectra for as-obtained and purified SiC nanowires were compared with the spectra of commercially available SiC nanomaterials. Principal vibrational modes have been identified. Reflectivity spectrum has been reconstructed by modeling of the dielectric function

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Wang, Rong, Aparna Naidu, and Yong Wang. "Oral Cancer Discrimination and Novel Oral Epithelial Dysplasia Stratification Using FTIR Imaging and Machine Learning." Diagnostics 11, no. 11 (November 17, 2021): 2133. http://dx.doi.org/10.3390/diagnostics11112133.

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The Fourier transform infrared (FTIR) imaging technique was used in a transmission model for the evaluation of twelve oral hyperkeratosis (HK), eleven oral epithelial dysplasia (OED), and eleven oral squamous cell carcinoma (OSCC) biopsy samples in the fingerprint region of 1800–950 cm−1. A series of 100 µm × 100 µm FTIR imaging areas were defined in each sample section in reference to the hematoxylin and eosin staining image of an adjacent section of the same sample. After outlier removal, signal preprocessing, and cluster analysis, a representative spectrum was generated for only the epithelial tissue in each area. Two representative spectra were selected from each sample to reflect intra-sample heterogeneity, which resulted in a total of 68 representative spectra from 34 samples for further analysis. Exploratory analyses using Principal component analysis and hierarchical cluster analysis showed good separation between the HK and OSCC spectra and overlaps of OED spectra with either HK or OSCC spectra. Three machine learning discriminant models based on partial least squares discriminant analysis (PLSDA), support vector machines discriminant analysis (SVMDA), and extreme gradient boosting discriminant analysis (XGBDA) were trained using 46 representative spectra from 12 HK and 11 OSCC samples. The PLSDA model achieved 100% sensitivity and 100% specificity, while both SVM and XGBDA models generated 95% sensitivity and 96% specificity, respectively. The PLSDA discriminant model was further used to classify the 11 OED samples into HK-grade (6), OSCC-grade (4), or borderline case (1) based on their FTIR spectral similarity to either HK or OSCC cases, providing a potential risk stratification strategy for the precancerous OED samples. The results of the current study support the application of the FTIR-machine learning technique in early oral cancer detection.

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Rohman, A., Dwi Larasati Setyaningrum, and Sugeng Riyanto. "FTIR Spectroscopy Combined with Partial Least Square for Analysis of Red Fruit Oil in Ternary Mixture System." International Journal of Spectroscopy 2014 (May 21, 2014): 1–5. http://dx.doi.org/10.1155/2014/785914.

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FTIR spectroscopy is a promising method for quantification of edible oils. Three edible oils, namely, red fruit oil (RFO), corn oil (CO), and soybean oil (SO), in ternary mixture system were quantitatively analyzed using FTIR spectroscopy in combination with partial least square (PLS). FTIR spectra of edible oils in ternary mixture were subjected to several treatments including normal spectra and their derivative. Using PLS calibration, the first derivative FTIR spectra can be exploited for determination of RFO; meanwhile, the second derivative spectra were preferred for determination of CO and SO. The R2 values obtained for the relationship between actual and FTIR predicted values of RFO, CO, and SO were 0.9863, 0.9276, and 0.9693, respectively. The root mean square error of calibration (RMSEC) values obtained were 1.59, 1.72, and 1.60% (v/v) for RFO, CO, and SO, respectively. The result showed that FTIR spectroscopy offers accurate and reliable technique for quantitative analysis of RFO, CO, and SO simultaneously in ternary mixture systems. Besides, the developed method can be extended for analysis of CO and SO as adulterants in RFO.

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Huleihel, Mahmoud, Mark Karpasas, Marina Talyshansky, Yelena Souprun, Yelena Doubijanski, and Vitaly Erukhimovitch. "MALDI–TOF and FTIR microscopy analysis of blood serum from diarrhea patients." Spectroscopy 19, no. 2 (2005): 101–8. http://dx.doi.org/10.1155/2005/989054.

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Mass‒spectroscopic and vibrational spectroscopic methods were applied for the analysis of human blood samples from healthy subjects and patients in order to detect spectral peaks which might serve as biomarkers for monitoring and identification of specific diseases. In the present study samples of serum were obtained from healthy and patient persons suffering from diarrhea and analyzed by matrix-assisted laser desorption/ionization time-of-flight (MALDI–TOF) and microscopic Fourier transform infrared spectroscopy (FTIR). The results obtained by both spectroscopic techniques show similar and consistent spectral peaks in all the examined sera obtained from healthy persons. In all tested patient samples two unique interesting peaks appeared atm/z11,553 and 11,710 in MALDI-TOF spectra and a peak at area 1600 cm−1was significantly reduced in all of the tested patient samples in FTIR spectra. These parameters might be used as a basis for developing a spectral method for the detection and identification of specific human diseases and probably other disorders. It seems that a combination of these two techniques may provide much more reliable results for the detection and identification of various abnormalities.

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48

TAMILSELVI, D., N. VELMANI, and K. RATHIDEVI. "EFFECT OF Ni-DOPING ON THE STRUCTURAL AND OPTICAL PROPERTIES OF ZnO NANOPARTICLES PREPARED BY CHEMICAL PRECIPITATION METHOD." Journal of Ovonic Research 16, no. 2 (March 2020): 123–30. http://dx.doi.org/10.15251/jor.2020.162.123.

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Undoped ZnO nano particles and Ni doped ZnO nanoparticles prepared by chemical precipitation method and assessed for their structural, morphological and optical properties. The prepared undoped and Ni doped ZnO nanoparticles were characterized by using X-ray diffraction (XRD), Fourier transform infrared spectral (FTIR), UV-Visible spectrophotometer, Scanning electron microscopy (SEM) and Energy Dispersive X-ray analysis (EDAX), Photoluminescence spectra (PL). XRD pattern shows the purity of prepared undoped and Ni doped ZnO nanoparticles size. Scanning electron microscopy (SEM) observations revealed remarkable change in morphology of the prepared samples. The presence of functional groups and chemical bonding was confirmed by FTIR and UV analysis. The defect states were revealed from the UV and visible emissions of the photoluminescence spectra.

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49

TAMILSELVI, D., N. VELMANI, and K. RATHIDEVI. "EFFECT OF Ni-DOPING ON THE STRUCTURAL AND OPTICAL PROPERTIES OF ZnO NANOPARTICLES PREPARED BY CHEMICAL PRECIPITATION METHOD." Journal of Ovonic Research 16, no. 2 (March 2020): 123–30. http://dx.doi.org/10.15251/jor.2020.161.123.

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Анотація:

Undoped ZnO nano particles and Ni doped ZnO nanoparticles prepared by chemical precipitation method and assessed for their structural, morphological and optical properties. The prepared undoped and Ni doped ZnO nanoparticles were characterized by using X-ray diffraction (XRD), Fourier transform infrared spectral (FTIR), UV-Visible spectrophotometer, Scanning electron microscopy (SEM) and Energy Dispersive X-ray analysis (EDAX), Photoluminescence spectra (PL). XRD pattern shows the purity of prepared undoped and Ni doped ZnO nanoparticles size. Scanning electron microscopy (SEM) observations revealed remarkable change in morphology of the prepared samples. The presence of functional groups and chemical bonding was confirmed by FTIR and UV analysis. The defect states were revealed from the UV and visible emissions of the photoluminescence spectra.

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50

Pijanka, Jacek K., Nicholas Stone, Gianfelice Cinque, Ying Yang, Achim Kohler, Katia Wehbe, Mark Frogley, et al. "FTIR microspectroscopy of stained cells and tissues. Application in cancer diagnosis." Spectroscopy 24, no. 1-2 (2010): 73–78. http://dx.doi.org/10.1155/2010/587947.

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It is widely accepted that FTIR spectroscopy has a huge potential in cancer diagnosis. However further work is required to bring this technique into pathology departments. One of the areas where big efforts will be required is the development of cell spectra databases to be used in the diagnosis of cancer. Presently, unstained cytology and tissue samples are studied with FTIR spectroscopy. However, it is not always possible to identify in unstained samples the types of cells present. In order to achieve this, samples need staining after FTIR spectra have been obtained. We have recently shown it is possible to obtain FTIR spectra of stained cells using a synchrotron source (10.1038/labinvest.2010.8). This allows recording FTIR spectra from cells already characterized by pathologists. In order to further this work, we have now obtained FTIR spectra from stained (Papanicolau or Haematoxylin & Eosin) single cells using a benchtop spectrometer. This would be the logical step towards a clinical application in cancer diagnosis. The data here presented show that staining caused a decreased intensity of the peaks at 2920 cm−1and 2850 cm−1, and the appearance of stronger peaks at 1374 cm−1and 1040 cm−1. The clinical applications are discussed.

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