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The title molecule, N-(4-Nitrobenzoyl)-S-(2-hydroxyethyl)-carbamodithioate, (C10H10N2O4S2), was synthesized and its structure verified by single crystal X-ray diffraction and FT-IR, 1H-NMR, 13C-NMR...

Palm sugar which is also named brown sugar is powdered sugar produced from palm extract. Due to the high price of palm sugar, its contamination of materials that are cheap or low quality is inevitable. Usually, adulteration detection is done by conventional methods such as HPLC, TLC, or NMR which are time-consuming and require high-priced equipment, thus impractical for routine and large sample analysis. The aim of this research was to detect adulteration in palm sugar using Fourier Transform Infrared (FT-IR) spectroscopy. The samples used in this study were palm sugar as the main ingredient and coconut sugar as the adulterant. Two chemometric methods namely principal component analysis (PCA) and partial least squares regression (PLSR) were used for analysis. The absorbance data were taken at wavenumber 4000-650 cm-1 . Several concentrations of coconut sugar as an adulterant ranging from 0 to 100% were added to palm sugar. A total of 110 spectra of both pure and adulterated palm sugar samples were divided into two groups, i.e. 73 samples for developing calibration model and 37 samples for developing prediction model. The spectral obtained were pre-processed and analyzed using The Unscrambler X version 10.4. a total of six pre-processing methods were used, i.e., Normalization, Standard Normal Variate (SNV), Multiplicative Scatter Correction (MSC), and Baseline. Results showed that PCA was able to classify palm sugar based on adulterant concentrations. PLSR calibration model with a coefficient of determination (Rc2 ) of 0.94 and root mean square error of calibration (RMSEC) of 8% was obtained by applying the MSC method. The model was able to predict coconut sugar adulteration in palm sugar with Rp2 of 0.89 and root mean square error of prediction (RMSEP) of 10.68%. The results confirmed the potential of FT-IR spectroscopy for detecting adulteration in palm sugar.

Authenticity and adulteration detection are primary concerns of various stakeholders, such as researchers, consumers, manufacturers, traders, and regulatory agencies. Traditional approaches for authenticity and adulteration detection in edible oils are time-consuming, complicated, laborious, and expensive; they require technical skills when interpreting the data. Over the last several years, much effort has been spent in academia and industry on developing vibrational spectroscopic techniques for quality, authenticity, and adulteration detection in edible oils. Among them, Fourier transforms infrared (FT-IR) spectroscopy has gained enormous attention as a green analytical technique for the rapid monitoring quality of edible oils at all stages of production and for detecting and quantifying adulteration and authenticity in edible oils. The technique has several benefits such as rapid, precise, inexpensive, and multi-analytical; hence, several parameters can be predicted simultaneously from the same spectrum. Associated with chemometrics, the technique has been successfully implemented for the rapid detection of adulteration and authenticity in edible oils. After presenting the fundamentals, the latest research outcomes in the last 10 years on quality, authenticity, and adulteration detection in edible oils using FT-IR spectroscopy will be highlighted and described in this review. Additionally, opportunities, challenges, and future trends of FT-IR spectroscopy will also be discussed.

The lime juice is one of the products that has always fallen victim to fraud by manufacturers for reducing the cost of products. The aim of this research was to determine fraud in distributed lime juice products from different factories in Iran. In this study, 101 samples were collected from markets and also prepared manually and finally derived into 5 classes as follows: two natural classes (Citrus limetta, Citrus aurantifolia), including 17 samples, and three reconstructed classes, including 84 samples (made from Spanish concentrate, Chinese concentrate, and concentrate containing adulteration compounds). The lime juice samples were freeze‐dried and analyzed using FT‐IR spectroscopy. At first, principal component analysis (PCA) was applied for clustering, but the samples were not thoroughly clustered with respect to their original groups in score plots. To enhance the classification rates, different chemometric algorithms including variable importance in projection (VIP), partial least square‐discriminant analysis (PLS‐DA), and counter propagation artificial neural networks (CPANN) were used. The best discriminatory wavenumbers related to each class were selected using the VIP‐PLS‐DA algorithm. Then, the CPANN algorithm was used as a nonlinear mapping tool for classification of the samples based on their original groups. The lime juice samples were correctly designated to their original groups in CPANN maps and the overall accuracy of the model reached up to 0.96 and 0.87 for the training and validation procedures. This level of accuracy indicated the FT‐IR spectroscopy coupled with VIP‐PLS‐DA and CPANN methods can be used successfully for detection of authenticity of lime juice samples., In this work, the authenticity of commercial lime juice was detected and quantified using FT‐IR spectroscopy coupled with the VIP variable selection and CPANN models. The main advantage of the present contribution is the diversity of the calibrating samples which include broad ranges of natural, synthetic, and adulterated lime juice samples. Therefore, applicability domain of the developed discriminative model in this work would be broad and wide which is a needed property in fraud detection in lime juice industry.

BACKGROUND The botanical origin of honey attracts both commercial and research interest. Consumers' preferences and medicinal uses of particular honey types drive the demand for the determination of their authenticity with regard to their botanical origin. This study presents the discrimination of thyme, multi-floral. and honeydew honeys by Fourier-transform infrared (FTIR) and ultraviolet (UV) absorption spectroscopy combined with multivariate statistical analysis. UV absorption spectroscopy was applied without any dilution of the sample using a custom-made cuvette. FTIR and UV absorption spectroscopic data were processed by means of the orthogonal partial least squares discriminant analysis. RESULTS The optimal classification of floral and honeydew honeys was accomplished with UV spectroscopy with a successful estimation of 92.65% for floral honey and 91.30% for honeydew honey. The discrimination of thyme versus the multi-floral honey was best achieved with FTIR, with a correct classification of 95.56% and 100% for multi-floral and thyme honey respectively. Furthermore, our findings revealed the region of 2400-4000 cm-1 of the FTIR spectra as the most significant for this discrimination. CONCLUSION This work demonstrates that optical spectroscopic techniques in combination with multivariate statistical analysis can be a rapid, low-cost, easy-to-use approach for the determination of the botanical origin of honey without sample pretreatment. © 2021 Society of Chemical Industry.

The formation of Ho(III)-containing polyoxotungstates in acidified to different acidity Z = ν(H+)/ν(WO42–) = 0.80, 1.17, 1.29, and 1.50 solutions of the Na2WO4 – HNO3 – Ho(NO3)3 – H2O system was studied. The conditions for the synthesis of Na9[Но(W5O18)2]·23H2O from the aqueous solution of sodium tungstate acidified to Z=0.80 and with acetone admixture were elaborated. The FT–IR spectroscopy was used to determine the belonging of anion [Ho(W5O18)2]9– in the synthesized compound to the Peacock–Weakley type of structure. By the method of scanning electron microscopy salt is proved to be single-phase, and its grain size is in the range 200-400 nm. The technique developed in this work for the preparation of sodium decatungstoholmiate(ІІІ) is new and differs in that it allows one to synthesize a normal salt, which can be used for the synthesis of other normal salts of sodium heteropoly decatungstolanthanidates(ІІІ). As a result of attempts to synthesize salts by the interaction of holmium(III) nitrate with aqueous solutions of sodium tungstate acidified to Z = 1.17 and 1.29, X-ray amorphous solids were obtained, which most likely are mixtures of paratungstate B and holmium heptatungstate. Using the methods of chemical analysis and FTIR spectroscopy, the conditions for the formation of a sodium-holmium double salt with lacunar undecatungstate anion, derived from Keggin structure Na2Ho2[Нo2(H2O)10W22O72(OH)2]·46H2O are established. Procedure for the synthesis of holmium(III) paratungstate B Ho10[W12O40(OH)2]3·54H2O by the exchange reaction of holmium(ІІІ) nitrate with sodium paratungstate B was elaborated, and by the method of scanning electron microscopy it is proved to be single–phase. It was found that the grain size of the sample is in the range 200–450 nm. The absence of sodium(I) ions in the composition of the synthesized salt was proved by atomic absorption spectroscopy and EDX. Microphotographs of the salt powders Na9[Но(W5O18)2]·23H2O and Ho10[W12O40(OH)2]3·54H2O in the characteristic X–ray radiation show no zones with different surface morphologies, and show uniform distribution of Na, Ho, W, O is observed without segregation, which confirms the single–phase nature of the products.

An effective and easy to implement ligand exchange strategy is paramount to the design of stable and multifunctional gold and other inorganic nanocolloids. This is also crucial for their use in bio...

The present study has been carried out to investigate the mechanisms of sol–gel reactions using TEOS as precursor in the presence of acid or base catalyst. The gels were prepared by hydrolysis of TEOS using hydrochloride acid or ammonium hydroxide catalyst. The obtained gels were also characterized by FTIR spectroscopy. The results of FTIR spectroscopy indicated the existence of silanol and siloxane bonds; due to the formation of hydrolyzed species as reactive intermediate compounds in initial stage converted by condensation reactions to gels as ultimate products. Accordingly, appropriate mechanisms have been proposed for sol – gel reaction using TEOS as precursor in the presence of acid or base catalyst. These mechanisms involve three-steps SN2 mechanisms for base catalyzed hydrolysis reaction of TEOS and SN1 mechanisms for acid catalyzed hydrolysis reaction of TEOS. Three mechanisms have been also proposed for condensation reaction as second stage in sol-gel process. These mechanisms include alcoxolation, oxolation and oltaion.

Identification and determination of diethylene glycol (DEG) in glycerin-based products was successfully achieved using FT-IR spectroscopy. Studied samples included 0.5% to 20% by mass DEGspiked into cough syrup, two paracetamol syrup formulations, and two food supplements. The characteristic DEGwavenumbers at 881 cm -1 and 1083 cm -1 were used for its quantitative determination in the studied samples. A very good accuracy in determining the DEG fraction was achieved with a mean error% of ±2.02% to ±7.69% upon using the corrected absorbance at 881 cm -1 . The corrected absorbance at 1083 cm -1 band was used in the case of paracetamol formulations and resulted in a mean error% ranging from ±2.50% to ±10.28%. The values of limit of detection of the current method ranged from 0.051% to 0.068% DEG for all studied samples.

The quality of wheat flour (WF) is among the highest of cereal flours and therefore, it is one of the most expensive flours for manufacturing food products. In developing countries, adulteration of WF by mixing up with lower price cereal flours is often seen. Hence, the classification and determination of the adulteration quantity in WF is of great interest. The aim of this research was to evaluate the feasibility of FT-IR spectroscopy and multivariate data analysis methods for the detection of adulteration of WF with the most likely adulterant barley flour (BF). For this purpose, 20 pure cereal flours and 120 flour blends were analyzed using FT-IR spectroscopy with chemometrics. The spectra were collected in the region of 4000-450 cm-1 and up to 15 wavenumber regions corresponding to peaks of flour constituents were selected. The classification limit value of soft independent modeling of class analogies for detection of BF added to WF was better than 1 Additionally, 98.25% of the flours were correctly classified by linear discriminant analysis. Partial least squares regression was adopted to construct a model to quantify the adulteration level. The root mean square error of calibration for sample calibration associated forecast parameters was 0.34-1.34% and the root mean square error of cross validation was 0.36-1.50 Thus, the BF adulterant could be detected down to approximately 0.30%.

K15NaSn5F36 crystallizes in the hexagonal crystal system with space group P63/m and lattice parameters of a = 1060.3(2) and c = 2011.9(4) pm. The unit-cell volume amounts to 1.9588(7) nm3. Its fundamental building blocks are quasi-isolated [SnF6]2− and [NaF6]5− octahedra, which are imbedded into a matrix of potassium cations. Within the structure, these units form a layer-like arrangement consisting either of mixed [SnF6]2−/[NaF6]5− or pure [SnF6]2− layers. The structural model was further confirmed by BLBS and CHARDI calculations.

Monitoring of water oxidation by the established Co cubane catalyst Co4O4(OAc)4(py)4 (abbrev. Co4O4, OAc = acetate, py = pyridine) by time-resolved rapid-scan ATR FT-IR spectroscopy revealed the O–...

The recognition of microplastics (MPs) in environmental samples via FT-IR is challenging due to a plethora of factors can lead to significant variances in measured spectra. Conventional library search approaches compare the observed spectrum with spectra in reference libraries, which will lead to errors due the variance in spectra. Motivated to tackle this challenge, this study explores the feasibility of leveraging deep learning for automatic MP recognition via FT-IR spectroscopy. More specifically, a deep convolution neural network (CNN) architecture, referred to here as PlasticNet, is introduced for the purpose of automatic MP recognition. PlasticNet was trained on a large corpus of FT-IR spectra of different plastic types in order to learn discriminative spectral features characterizing each plastic type. Experimental results showed that PlasticNet was capable of recognizing between MPs in an effective way and at a faster speed compared with libary search.

A series of optical properties of some natural dyes are reported and discussed. The studied bio-dyes were extracted from different spices and showed interesting photosensitive properties. Thin film...

The potassium oxidofluoridostannate(IV) fluoride K5Sn2OF11 was synthesized via a solid-state route at T = 300°C in arc-weldeded copper ampoules. It crystallizes in the orthorhombic system in the acentric space group Ama2 (no. 40) with a unit cell volume of V = 2.5727(4) nm3. The cell parameters are a = 1758.3(2), b = 2452.3(2) and c = 596.7(1) pm. As a main structural motif, K5Sn2OF11 exhibits two different kinds of dinuclear [Sn2OF11]5‒ units, which are embedded into a matrix consisting of potassium cations and fluoride anions. The substance was characterized by single-crystal and powder X-ray diffraction, as well as by FT-IR spectroscopy.

WOS: 000472522700005, In this study, (+/-)-1,2-Dehydroaspidospermidine was analyzed by elemental analysis, H-1 and C-13 NMR, and FT-IR spectra. Also, because the starting geometry is essential to evaluate the structural, electronic, and spectral properties of this compound, we used the potential energy surface (PES) scan by the B3LYP/6-31G(d,p) hybrid functional to determine the stable structures of the (+/-)-1,2-Dehydroaspidospermidine. Thus, three stable conformations of the compound were used in all of the electronic and spectroscopic simulations performed by the M06-2X, G96LYP, and B3LYP functionals at the 6-311++G(d,p) basis set in a vacuum and chloroform. After the observed and simulated FT-IR and NMR data were compared, the second order perturbative theory in the NBO (Natural Bond Orbital) basis was used to interpret the critical donor-acceptor interactions; the dominant contribution to the lowering of the second order energy for all conformers was the pi -> pi* and sigma -> pi* interactions. Also, we used both NLO (Non Linear Optic) and FMO (Frontier Molecular Orbital) analyses to investigate the non-linear optical property and the biochemical reactivity of the compound. The results of this work demonstrated that the compound has an available non-linear optical property (beta=6.62 x 10(-30) esu) that can be used in optoelectronic technology, and, besides, it has biological activity because of its strong intramolecular interactions., Scientific and Technological Research Council of Turkey (TUBITAK) [112T503]; Sivas Cumhuriyet University, Scientific Research Projects Department [CUBAP: EGT-072], This work was supported by the Scientific and Technological Research Council of Turkey (TUBITAK, Project No.112T503); Sivas Cumhuriyet University, Scientific Research Projects Department (Grant number: CUBAP: EGT-072) for financial support. All calculations have been carried out at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure).

In previous studies of marine debris or microplastics ( O antisymmetric in plane stretching band only existed in natural fibers even after the weathering and digestion treatments. The mixture of semi-synthetic and natural fibers from the real field samples was also easily distinguished using the characteristic band at 1105 cm−1. Our results suggest that the characteristic band at 1105 cm−1 could be an ideal reference to distinguish natural and semi-synthetic fibers in field microplastic investigations. We also proposed a practical method to enhance the library of polymer spectra and improve the accuracy of semi-synthetic microplastic identification.

Aims: To detect the adulterant in edible oil rapidly. Study Design: Authenticity and adulteration detection in edible oils are the increasing challenges for researchers, consumers, industries and regulatory agencies. Traditional approaches may not be the most effective option to combat against adulteration in edible oils as that’s are complex, laborious, expensive, require a high degree of technical knowledge when interpreting data and produce hazardous chemical. Consequently, a cost effective, rapid and reliable method is required. Place and Duration of the Study: The experiment was conducted jointly in the laboratory of the Department of Food Technology and Rural Industries, Bangladesh Agricultural University, Mymensingh and the Institute of Food Science and Technology, BCSIR, Dhaka. Methods: In this study, Fourier Transform Infrared spectroscopy coupled with multivariate analysis was used for adulteration detection in sunflower and rice bran oil. Sunflower oil was adulterated with soybean oil in the range of 10-50% (v/v) and rice bran oil was adulterated with palm oil in the range of 4-40% (v/v) at approximately 10% and 5% increments respectively. FTIR spectra were recorded in the wavenumber range of 4000-650cm-1. Results: FTIR spectra data in the whole spectral range and reduced spectral range were used to develop a partial least square regression (PLSR) model to predict the level of adulteration in sunflower and palm oils. Good prediction model was obtained for all PLSR models with a coefficient of determination (R2) of >= 0.985 and root mean square errors of calibration (RMSEC) in the range of 0-1.7325%. Conclusion: The result suggested that FTIR spectroscopy associated with multivariate analysis has the great potential for a rapid and non-destructive detection of adulteration in edible oils laborious conventional analytical techniques.

This paper, reports for the first time the green synthesis of the polymorphs I and II of new pharmaceutical co-crystals lamivudine:theophylline in solid-phase, through the mixture between lamivudine and theophylline (both active pharmaceutical ingredients-APIs) in the proportion of 1:1 by neat grinding and liquid assisted grinding (10 μL ethanol). Fourier transform-infrared (FT-IR) spectroscopy and multivariate curve resolution with alternating least-squares (MCR-ALS) were employed as non-invasive analytical methodology for the at-line green synthesis monitoring of the novels lamivudine:theophylline co-crystals. By MCR-ALS it was possible to identify each component present in a complex matrix, with strong spectral overlapping, containing lamivudine, theophylline, and the novel lamivudine:theophylline co-crystal with high confidence based on the comparison of the pure and recovered spectral and concentration profiles. This model allowed to identify the end of the reaction and understand the mechanism involved in the synthesis through the identification of the intermediates present in the synthesis process. Also, MCR-ALS model estimated the concentration of co-crystal polymorph I with a root mean square error of prediction (RMSEP) and the percentage relative error of prediction (REP%) equal to 3.323 (w/w) and 9.9%, respectively. These were good results since the spectral profile of cocrystal and the physical mixture of its APIs present strong spectral overlapping in their spectral domain. Therefore, the quantification of the co-crystal between its APIs (lamivudine and theophylline) certified that the co-crystal as final product was obtained, collaborating with the results obtained by differential scanning calorimetry (DSC) and X-ray powder diffraction (XRPD).

The impact of asphalt cement ageing on pavement durability is a well-known phenomenon for pavement engineers, yet due to complexity in the chemical structure of asphalt cement, not understood thoro...

In this paper, we investigated the influence of steam treatment on structural group composition of resins and asphaltenes of heavy oil. The object of investigation was oil-saturated rocks from Riph...

Background: Paris polyphylla var. Yunnanensis (PPY) is used in the clinical treatment of tumors, hemorrhages, and anthelmintic. Objective: The aim of this study is to determine total flavonoids of PPY in the Yunnan and Guizhou Provinces, China. Methods: In this study, total flavonoids were determined by UV spectrophotometry at first. Then, Fourier transform mid-infrared (FT-IR) based on various pretreatments include standard normal variate (SNV), first derivative (FD), second derivative (SD), Savitzky-Golay (SG), and orthogonal signal correction (OSC) were investigated. In addition, several relevant variables were screened by competitive adaptive reweighted sampling (CARS). The contentof total flavonoids and selected variables of FT-IRwere used to establish a partial least squares regression for PPY in different regions. Results: The results indicated that CARS was an effective method for decreasing the variable of thedatabase and improving the prediction of the model.FT-IR with pretreatment SNV + OSC + FD + SG had thebest performance, with R2 > 0.9 and residual predictive deviation = 3.3515, which could be used forthe predictive model of total flavonoids. Conclusions: Those results would provide a fast and robust strategy for the determination of total flavonoids of PPY in different geographical origin. Highlights: Various pretreatments, including SNV, FD, SD, SG, and OSC, were compared; several relevant variables were selected by CARS; and the content of total flavonoids and selected variable were used to establish a partial leastsquares regression for PPY in different regions.

Samples of needles from European spruce Picea abies and Scots pine Pinus sylvestris L. that were collected in Tver in zones with different anthropogenic impacts were investigated. The chemical compositions of conifer needles in different years of life were determined. IR and UV absorption spectra were used to compare pollutant accumulations in needles of different conifer species at collection points with similar anthropogenic impacts. The dependence of the qualitative chemical composition of the needles on the type of pollutant (depending on the collection point) was determined.

Wine aging in wooden barrels can alter a wine's sensory features through the extraction of wood phenols such as lignins, volatile phenols and hydrolysable tannins. Among the hydrolysable tannins, ellagitannins have been found not only to modify a wine's sensory character but also to generate new products with compounds already present in wines. For this reason, their quantification is of high importance. However, ellagitannin analysis requires the use of sophisticated equipment and many preparative steps, making their quantification in wines cost effective and laborious. In this study, the feasibility of FT-IR spectroscopy coupled with chemometrics for the quantification of ellagitannin concentration in wines was examined for the first time. Partial Least Squares regression was used to construct calibration models, using the fingerprint region of the spectrum, 1821-950 cm−1 (first derivative in range). The correlation coefficient (R2) was found 0.93, the Root-Mean-Square Error of Calibration RMSEC was 1.17 and the Root-Mean-Square Error of Prediction, RMSEP was 1.57. The results indicate that FT-IR could be used for a quick, non destructive and economical estimation of a wine's total ellagitannin content.

This study deals with the influence of electron beam irradiation (EBI) on the wettability of Norway spruce surface samples. To evaluate this possible effect in detail, the changes in chemistry and ...

Since Cannabis species include psychoactive varieties containing high levels of Δ9-tetrahydrocannabinol (THC), psychotropic properties could be wrongly attributed to hemp-seed oil obtained from Cannabis sativa. Hemp oil does not exert any psychotic effect; on the contrary, it may provide significant health benefits, because it has an optimum proportion of ω-6 to ω-3 fatty acids (3:1). Six samples of cold pressed hemp-seed oils were studied by nuclear magnetic resonance (NMR) and Fourier-transformed infrared spectroscopy (FT-IR). These methods were applied to evaluate the ratio of ω-6 to ω-3 fatty acids and to control the quality of hemp oils. FT-IR method allowed us to distinguish three oils with the highest level of γ-linolenic acid. Additionally, NMR spectroscopy was applied to determine the ω-6 to ω-3 ratio. The outcomes of the NMR experiment are in agreement with GC outcomes measures. The results indicate that NMR and FT-IR may be used in routine evaluation of hemp-seed oil quality as a fast and reliable method of verification of ω-6 to ω-3 ratio and origin of the oil.

Wood has been extensively used as a material for different applications over the years, therefore the understanding of different degradation processes in various environments is of great importance. In this study, the infrared spectroscopy, X-ray diffraction and chemometric methods were used to evaluate and compare the structure of archaeological and artificially degraded oak wood. The results clearly show that modifications in the structure of archaeological wood are related to the position of the material in the log (sapwood and heartwood), thus the extent of wood degradation. To identify the possible factors influencing these effects, the control wood samples were exposed to artificial white rot biodegradation with Coriolus (Trametes) versicolor and to alkali treatment (with NaOH solution). Due to the structural similarities between biodegraded wood and control or archaeological samples, this type of decay is likely to occur during natural ageing along with degradation produced by other environmental factors. Further, no real similarity was identified between the alkali treated wood and archaeological samples, indicating that such degradation does not affect wood under natural conditions.

The interactions of HSA with DA have received great attention nowadays due to its significant effect in the biomedical field and overall health. The main aim of this work is to examine the interaction between DA and HSA at physiological conditions. Upon addition of DA to HSA, the fluorescence emission was quenched with quenching constant Kq = 1.32 × 109 L⋅mol−1⋅s−1 and the binding constant of DA with HSA is found to be K = 4.4 × 102 mainly indicating dynamic quenching. The HSA conformation was altered upon binding of DA to HSA with an increase in α-helix and a decrease in β-sheets suggesting unfolding of HSA secondary structure due to weak intermolecular interaction with HSA. In view of the evidence presented, it is important to understand the details of the interactions of HSA with DA which will be crucial in the design of new DA-inspired drugs and help revealing vital details to better understand the HSA’s role as a transporter for many drugs.

Autistic Spectrum Disorder (ASD), considered a neurological development disorder, is characterized by different degrees of deficit in communication, social interaction, and learning, accompanied by repetitive and stereotyped patterns of behavior. The diagnosis of ASD is extremely complex due to the unknown etiopathogenesis and the diversity of symptoms presented by the individuals. This study aimed to evaluate the effectiveness of Fourier Transform Infrared Spectroscopy (FT-IR) as a tool for the diagnosis of ASD in saliva. Saliva samples from 14 volunteers, 7 with ASD (G-A) and 7 Neurotypical (G-N) were analyzed. The collected samples were centrifuged, 20 µL of supernatant was deposited on calcium fluoride (CaF2) windows and dehydrated for 10 min. The FT-IR spectra were obtained by a spectrophotometer coupled to a microscope, in the spectral range of 4000 cm-1 - 900 cm-1 , with 32 scans, and spectral resolution of 4 cm-1 . A total of 112 spectra were collected, and their averages were submitted to Cluster analysis by the second derivative, aiming to group the results by similarity. FT-IR Spectroscopy was able to separate approximately 86% of the samples in the corrected group. The results showed an increase in bands related to proteins and hormones. Individuals diagnosed with ASD often have increased levels of stress, difficulty in interpersonal relationships, and reduced salivary flow compared to neurotypical individuals. ASD patients present a higher concentration of proteins and cortisol release in the saliva. FT-IR spectroscopy is a promising tool to differentiate saliva samples from ASD patients from neurotypical individuals.

Fourier Transform-Infrared (FT-IR) absorption spectroscopy has been used to investigate pathophysiological changes caused by sepsis. Sepsis has been defined as a potentially fatal organic dysfunction caused by a dysregulated host response to infection and can lead a patient to risk of death. This study used samples consisting of the blood plasma of mice which were induced to sepsis state, compared to a healthy group using FT-IR associated with attenuated total reflectance (ATR) spectroscopy. For statistical analysis, principal components analysis (PCA) and linear discriminant analysis (LDA) were applied, independently, to the second derivative spectra of both the fingerprint (900−1800 cm−1) and the high wavenumber (2800−3100 cm−1) regions. The technique efficiently differentiated the blood plasma of the two groups, sepsis and healthy mice, the analysis indicating that fatty acids and lipids in the blood samples could be an important biomarker of sepsis.

International audience; The translation terminator Sup35p assembles into self-replicating fibrillar aggregates that are responsible for the [PSI þ ] prion state. The Q/N-rich N-terminal domain together with the highly charged middle-domain (NM domain) drive the assembly of Sup35p into amyloid fibrils in vitro. NM domains are highly divergent among yeasts. The ability to convert to a prion form is however conserved among Sup35 orthologs. In particular, the Yarrowia lipolytica Sup35p stands out with an exceptionally high prion conversion rate. In the present work, we show that different Yarrowia lipolytica strains contain one of two Sup35p orthologs that differ by the number of repeats within their NM domain. The Y. lipolytica Sup35 proteins are able to assemble into amyloid fibrils. Contrary to S. cerevisiae Sup35p, fibrils made of full-length or NM domains of Y. lipolytica Sup35 proteins did not bind Thioflavin-T, a well-known marker of amyloid aggregates.

Infrared spectroscopy has a variety of uses in the paper industry, including competitive analysis, quantification of individual components, and identification of contaminants in both the manufacturing process and the product. This chapter reviews instrumentation and techniques that can be used to study paper or paper-related samples. It addresses data interpretation and some paper-related FT-IR applications. When selecting an instrument for testing or purchase the user should consider function, simplicity, reliability, and availability. There is a wide variety of sampling equipment offered for use in commercial FT-IR spectrometers. Neat film sampling is generally a quick and effective way to obtain spectra of liquid samples or extractions of solid samples. There are two sample-related problems which may arise with liquid samples. First, the sample may be too concentrated or too strong an absorber. Second, the sample may be too dilute or too weak an absorber.

Secoiridoids could be used as a potential new drug for the treatment of hepatic disease. The content of secoiridoids of G. rigescens varied in different geographical origins and parts. In this study, a total of 783 samples collected from different parts of G. rigescens in Yunnan, Sichuan, and Guizhou Provinces. The content of secoiridoids including gentiopicroside, swertiamarin, and sweroside were determined by using HPLC and analyzed by one-way analysis of variance. Two selected variables including direct selected and variable importance in projection combined with partial least squares regression have been used to establish a method for the determination of secoiridoids using FT-IR spectroscopy. In addition, different pretreatments including multiplicative scatter correction (MSC), standard normal variate (SNV), first derivative and second derivative (SD), and orthogonal signal correction (OSC) were compared. The results indicated that the sample (root, stem, and leaf) with total secoiridoids, gentiopicroside, swertiamarin, and sweroside from west Yunnan had higher content than samples from the other regions. The sample from Baoshan had more total secoiridoids than other samples for the whole medicinal plant. The best performance using FT-IR for the total secoiridoid was with the direct selected variable method involving pretreatment of MSC+OSC+SD in the root and stem, while in leaf, of the best method involved using original data with MSC+OSC+SD. This method could be used to determine the bioactive compounds quickly for herbal medicines.

An exclusive trace of CH4 direct carboxylation with CO2 by a stepwise technology was investigated using in-situ FT-IR spectroscopy. The results showed that CH4 was dissociated to atomic hydrogen and M-CHx species on catalyst surface when it was first introduced in the system, then CO2 was inserted into the intermediate to direct carboxylate. Finally, the subsequent adsorption of CH4 provided active hydrogen for the species of previous surface reaction, thus leading to the formation of the product. It was also found that the first introduction of CO2 on the surface of the &ldquo, clean&rdquo, catalyst might likely react with surface H species, which had an irreversible effect on the catalytic activity of CH4.

Identification of extracellular vesicle (EV) subpopulations remains an open challenge. To date, the common strategy is based on searching and probing set of molecular components and physical properties intended to be univocally characteristics of the target subpopulation. Pitfalls include the risk to opt for an unsuitable marker set – which may either not represent the subpopulation or also cover other unintended subpopulations – and the need to use different characterization techniques and equipment. This approach focused on specific markers may result inadequate to routinely deal with EV subpopulations that have an intrinsic high level of heterogeneity. In this paper, we show that Fourier-transform Infrared (FT-IR) spectroscopy can provide a collective fingerprint of EV subpopulations in one single experiment. FT-IR measurements were performed on large (LEVs, ~600 nm), medium (MEVs, ~200 nm) and small (SEVs ~60 nm) EVs enriched from two different cell lines medium: murine prostate cancer (TRAMP-C2) and skin melanoma (B16). Spectral regions between 3100–2800 cm−1 and 1880–900 cm−1, corresponding to functional groups mainly ascribed to lipid and protein contributions, were acquired and processed by Principal Component Analysis (PCA). LEVs, MEVs and SEVs were separately grouped for both the considered cell lines. Moreover, subpopulations of the same size but from different sources were assigned (with different degrees of accuracy) to two different groups. These findings demonstrate that FT-IR has the potential to quickly fingerprint EV subpopulations as a whole, suggesting an appealing complement/alternative for their characterization and grading, extendable to healthy and pathological EVs and fully artificial nanovesicles.

This paper constitutes an attempt at using FT-IR spectroscopy for the dating of historical and artistic artefacts made of poplar wood. It was decided to do the tests only on poplar (Populus spp.) to reduce a part of the typical wood variability, while poplar was chosen because it is widely present in Italian heritage, such as panel paintings, statues and furniture, and these objects cannot be dated by dendrochronology; also because 14C methodology has major limitations. Poplar artefacts from the fourteenth to the nineteenth century were selected, dated by means of documents, by attributions, or stylistically. In addition, recent poplar samples were selected as a reference. Wood flour were taken from the selected samples, discarding the surface layers that could have been influenced by oxidation phenomena. Before taking measurements with FT-IR, the wood meal was dried and the chemical extractives were removed. The results show the presence of a time-related trend, but the time factor is certainly not the only one that causes the variations within the spectra. After a discussion, it is therefore considered that the results do not allow at the current state to definitely produce a reliable reference for dating poplar wood artefacts through this methodology.