scholarly journals Effects of Fatty Acids, Fatty Amines and Propylene Glycol on Rat Stratum Corneum Lipids and Proteins in Vitro Measured by Fourier Transform Infrared/Attenuated Total Reflection(FT-IR/ATR) Spectroscopy.

1992 ◽  
Vol 40 (7) ◽  
pp. 1887-1892 ◽  
Author(s):  
Yoshikazu TAKEUCHI ◽  
Hidehito YASUKAWA ◽  
Yumiko YAMAOKA ◽  
Yuichi KATO ◽  
Yasuko MORIMOTO ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fourier Transform ◽  
Stratum Corneum ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Fatty Amines ◽  
Stratum Corneum Lipids ◽  
Ft Ir ◽  
Atr Spectroscopy

Discrimination of Soil-Borne Fungi Using Fourier Transform Infrared Attenuated Total Reflection Spectroscopy

2008 ◽  
Vol 62 (3) ◽  
pp. 302-305 ◽  
Author(s):  
Raphael Linker ◽  
Leah Tsror(LAHKIM)
Keyword(s):  
Fourier Transform ◽  
Success Rate ◽  
Fourier Transform Infrared ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Economic Damage ◽  
Genus Level ◽  
Ft Ir ◽  
Atr Spectroscopy ◽  
Soil Borne Fungi

Fourier transform infrared (FT-IR) attenuated total reflection (ATR) spectroscopy was used to discriminate five commonly encountered soil-borne fungi that cause severe economic damage to agriculture: Colletotrichum, Fusarium, Pythium, Rhizoctonia, and Verticillium. Contrary to previous studies related to microorganism discrimination using FT-IR-ATR spectroscopy, the pathogen samples were not dried on the ATR crystal, which is a time-consuming operation. Rather, after removing some pathogen filaments from the solution using tweezers, these were placed directly on a flat ATR crystal and pressure was applied using a pressure clamp. Following water subtraction, baseline correction, and normalization of the spectra, principal component analysis was used as a data-reduction step and canonical variate analysis was used for discrimination. Discrimination was performed at the genus level and at the strain level for Colletotrichum. For discrimination between the five fungi at the genus level, the success rate for the validation samples ranged from 75% to 89%. For discrimination between the two Colletotrichum strains, the success rate was 78%. Comparison with spectra of similar fungi dried on the ATR crystal showed that both types of spectra were very similar, indicating that drying the samples on the ATR crystal is not required and can be replaced by mathematical post-processing of the spectra. For routine analyses that involve rapid screening of very large amounts of samples, this approach allows for increasing significantly the number of samples that can be analyzed daily.

Comparative Investigation of Secondary Cell Wall Development in Cotton Fiber Near Isogenic Lines Using Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR FT-IR)

2019 ◽  
Vol 73 (3) ◽  
pp. 329-336 ◽  
Author(s):  
Yongliang Liu ◽  
Hee-Jin Kim
Keyword(s):  
Cell Wall ◽  
Fourier Transform ◽  
Secondary Cell Wall ◽  
Fiber Strength ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Near Isogenic Lines ◽  
Significant Difference ◽  
Ft Ir ◽  
Fiber Maturity

In this investigation, we applied previously proposed simple algorithms to analyze the attenuated total reflection Fourier transform infrared (ATR FT-IR) spectra of cotton fibers during secondary cell wall (SCW) biosynthesis. The infrared crystallinity ( CIIR) and maturity ( MIR) indices were compared from developmental fibers representing two pairs of upland cotton near isogenic lines (NILs). One pair of NILs consisted of Texas Marker-1 (TM-1) and an immature fiber ( im) mutant that differ in fiber maturity. The other pair of NILs included MD52ne and MD90ne that show variations in fiber strength. The observations revealed significant difference in the MIR values between developmental TM-1 and im NILs grown at a field in crop year 2015, and also a significant difference in the CIIR values between these NILs grown at the same field in crop year 2011. These different patterns of CIIR and MIR values during fiber development for the two different crop years indicated the impact of genetics and crop year on the development of fiber maturity and crystallinity of the TM-1 and im fibers. Furthermore, the tendency of linking CIIR with MIR values suggested that the im fibers have more CIIR development than the TM-1 fibers when the fibers have the similar MIR values. In contrast, the NIL pair having variations in fiber strength showed insignificant differences in the patterns of CIIR and MIR as well as the relationship between CIIR and MIR values. The results suggested that CIIR and MIR indices from ATR FT-IR measurement could be used to facilitate the understanding of how fiber genetics and crop year affect fiber maturity and crystallinity during SCW biosynthesis.

Chemometric Approach to a Rapid Attenuated Total Reflection Fourier Transform Infrared Analysis of Complex Heroin-Based Mixtures

2020 ◽  
pp. 000370282096971
Author(s):  
Nataša Radosavljević Stevanović ◽  
Milena Jovanović ◽  
Federico Marini ◽  
Slavica Ražić
Keyword(s):  
Principal Component Analysis ◽  
Fourier Transform ◽  
Principal Component ◽  
Fourier Transform Infrared ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Illegal Market ◽  
Ft Ir

Heroin is one of the most frequently seized drugs in Southeastern Europe. Due to the position in the Balkan route, the Republic of Serbia keeps important role in suppression of the trafficking of heroin for domestic and foreign illegal market. This research is aimed to provide a good scientific approach in the field of seized heroin analysis. Two different forms of heroin are present in the illegal market, mostly in mixtures with typical “cutting” agents: caffeine, paracetamol, and sugars. It was observed that the quantity of pure heroin in seized samples slightly increases from year to year. The aim of this study was to produce a reliable and fast procedure for classification of illicit heroin samples and determination of the concentration range of heroin in the samples. For that purpose, the attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR) technique was used and combined with such chemometric methods as principal component analysis, cluster analysis, and partial least squares. Principal component analysis (PCA) as an unsupervised model was used for exploratory purposes to identify trends, similarities, and differences between samples by reducing the dimensionality of the data. The cluster classification of examined samples turned out to be extremely useful to evaluate the possibilities of the ATR FT-IR technique to classify the samples appropriately into the patterns, the constituted clusters. Additionally, partial least square was the suitable method for the purpose of determination of the heroin hydrochloride concentration range in examined samples. It is proved that the joined application of spectroscopy and chemometrics can be extremely convenient and useful for forensic and drugs control laboratories.

scholarly journals The structural stability of protein antigens adsorbed by aluminium hydroxide in comparison to the antigens in solutions

2007 ◽  
Vol 21 (5-6) ◽  
pp. 257-268 ◽  
Author(s):  
Yiwu Zheng ◽  
Xuxin Lai ◽  
Henrik Ipsen ◽  
Jørgen Nedergaard Larsen ◽  
Henning Løwenstein ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Structural Stability ◽  
Aluminium Hydroxide ◽  
Storage Temperature ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Protein Antigens ◽  
Adsorbed Protein ◽  
Vaccine Immunogenicity ◽  
Atr Spectroscopy

It is believed that antigens should be adsorbed onto adjuvants in vaccines. The adsorption-modified structure of antigens is important to understand the mechanism of adjuvants and vaccine immunogenicity. The structural stability of antigens is of major importance. The changes in structure can be induced by degradation and/or increase of storage temperature. In this study the structural stability of two model antigens, bovine serum albumin (BSA) andβ-lactoglobulin (BLG) were compared when they were adsorbed onto aluminium hydroxide and when they were in solutions using Fourier transform infrared – attenuated total reflection (FTIR-ATR) spectroscopy. The structural stability of these two proteins was studied at different temperature and during storages. The present results showed that the structure of antigens can be stabilized by adsorption onto aluminium hydroxide. Non-adsorbed protein antigens present in vaccines may facilitate the degradation of the vaccine.

Novel Attenuated Total Reflection Fourier Transform Infrared Microscopy Using a Gem Quality Diamond as an Internal Reflection Element

2005 ◽  
Vol 59 (10) ◽  
pp. 1236-1241 ◽  
Author(s):  
Sanong Ekgasit ◽  
Pimthong Thongnopkun
Keyword(s):  
Fourier Transform ◽  
Total Internal Reflection ◽  
Fourier Transform Infrared ◽  
Normal Incidence ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Internal Reflection ◽  
The Novel ◽  
Infrared Microscope ◽  
Ft Ir

A novel technique for attenuated total reflection Fourier transform infrared (ATR FT-IR) spectral acquisition by an infrared microscope with a gem-quality faceted diamond as an internal reflection element (IRE) is introduced. Unlike conventional IREs, the novel diamond IRE has a sharp tip configuration instead of a flat tip configuration. Light at normal incidence was coupled into the diamond while the transflected radiation from the diamond was collected through the table facet by the built-in 15× Cassegrainian objective. The number of reflections in the novel diamond IRE equals two. The evanescent field generated under total internal reflection at the pavilion facet was exploited for ATR spectral acquisition of materials attached to the IRE. The observed ATR spectra were compared to those obtained via a traditional zinc selenide IRE.

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