In situ attenuated total reflectance FT-IR analysis of an enzyme-modified mid-infrared fiber surface using crystalline bacterial surface proteins

The use of a mid-infrared transmitting fiber to carry the infrared beam of an FT-IR spectrometer outside of the optical bench is reported. In addition it is demonstrated that it is possible to analyze samples using the fiber as an internal reflection element. The fiber is covered with a protective coating which can be removed for a short region, to allow contact with the sample over a controlled length. Two examples of the use of an optical fiber for remote sampling are discussed. The first shows that a spectrum of a liquid sample (2-butanone) can be easily measured, and the second shows how a fiber can be used to monitor the progress of curing reactions in thermoset composite materials. The spectrum of a resin was recorded before the cure by embedding the optical fiber in the graphite fiber/polyimide matrix resin prepreg, and then the progress of the cure was monitored during the curing process. This type of remote sampling shows tremendous potential for opening totally new areas of usage for FT-IR spectrometry, including the studies of hazardous materials, enclosed reactions, and processes that do not allow samples to be taken inside the spectrometer.

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Observations of surface-mediated reduction of Pu(VI) to Pu(IV) on hematite nanoparticles by ATR FT-IR

Radiochimica Acta ◽

10.1515/ract-2014-2372 ◽

2015 ◽

Vol 103 (8) ◽

Cited By ~ 9

Author(s):

Hilary P. Emerson ◽

Brian A. Powell

Keyword(s):

Fourier Transform ◽

Infrared Spectroscopy ◽

Attenuated Total Reflectance ◽

Mineral Surfaces ◽

Hematite Nanoparticles ◽

Total Reflectance ◽

Ft Ir ◽

First Time ◽

Mediated Reduction

AbstractPrevious studies have shown that mineral surfaces may facilitate the reduction of plutonium though the mechanisms of the reduction are still unknown. The objective of this study is to use batch sorption and attenuated total reflectance Fourier transform infrared spectroscopy experiments to observe the surface-mediated reduction of plutonium on hematite nanoparticles. These techniques allow for in situ measurement of reduction of plutonium with time and may lead to a better understanding of the mechanisms of surface mediated reduction of plutonium. For the first time, ATR FT-IR peaks for Pu(VI) sorbed to hematite are measured at ∼ 916 cm

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Chemometric analysis of attenuated total reflectance infrared spectra ofProteus mirabilisstrains with defined structures of LPS

Innate Immunity ◽

10.1177/1753425916647470 ◽

2016 ◽

Vol 22 (5) ◽

pp. 325-335 ◽

Cited By ~ 4

Author(s):

Paulina Zarnowiec ◽

Andrzej Mizera ◽

Magdalena Chrapek ◽

Mariusz Urbaniak ◽

Wieslaw Kaca

Keyword(s):

Ir Spectroscopy ◽

Infrared Region ◽

Attenuated Total Reflectance ◽

Mid Infrared ◽

Total Reflectance ◽

Typing Methods ◽

Ft Ir ◽

Tract Infections ◽

Ft Ir Spectroscopy

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

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A New Internal Reflection Element Design for High Optical Throughput in FT-IR

Applied Spectroscopy ◽

10.1366/0003702864508485 ◽

1986 ◽

Vol 40 (5) ◽

pp. 632-635 ◽

Cited By ~ 6

Author(s):

Robert G. Messerschmidt

Keyword(s):

Internal Reflection ◽

Attenuated Total Reflectance ◽

Angle Of Incidence ◽

Simple Design ◽

Total Reflectance ◽

Ft Ir ◽

Ir Analysis

A novel geometry for internal reflection elements is described. These elements have been found most useful in the FT-IR analysis of samples by attenuated total reflectance (ATR). Both single and multiple internal reflection elements are described. These elements provide three basic benefits. First, the geometry is such that an element may be exchanged for another of differing angle of incidence without the need for optical realignment of the sampling accessory. Second, for a given element thickness and width, the design allows a larger aperture over the conventional designs (parallelograms and trapezoids) for angles of incidence greater than 45 degrees, resulting in better sensitivity. Third, the elements are of a simple design, and are easy to fabricate.

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Control of Lignin Solubility and Particle Formation Modulates Its Antioxidant Efficiency in Lipid Medium: An In Situ Attenuated Total Reflectance FT-IR Study

Energy & Fuels ◽

10.1021/ef500368x ◽

2014 ◽

Vol 28 (7) ◽

pp. 4539-4544 ◽

Cited By ~ 2

Author(s):

Søren Barsberg ◽

Lisbeth G. Thygesen ◽

Anand R. Sanadi

Keyword(s):

Particle Formation ◽

Attenuated Total Reflectance ◽

Antioxidant Efficiency ◽

Total Reflectance ◽

Ft Ir ◽

Ir Study

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Polylactic Acid/Cellulose Fibres Based Composites for Food Packaging Applications

Materiale Plastice ◽

10.37358/mp.17.4.4923 ◽

2017 ◽

Vol 54 (4) ◽

pp. 673-677 ◽

Cited By ~ 4

Author(s):

Elisabeta Elena Popa ◽

Maria Rapa ◽

Ovidiu Popa ◽

Gabriel Mustatea ◽

Vlad Ioan Popa ◽

...

Keyword(s):

Chemical Structure ◽

Food Packaging ◽

Attenuated Total Reflectance ◽

Scanning Calorimetry ◽

Melt Mixing ◽

Cellulose Fibres ◽

Total Reflectance ◽

Ft Ir ◽

Ir Analysis ◽

And Migration

PLA-based composites containing CF in the range 0 to 10 wt. % were prepared by melt mixing technique. The prepared composites were investigated in terms of processability, chemical structure (by Attenuated total reflectance - Fourier Transform Infrared - ATR-FT-IR analysis), thermal (Differential Scanning Calorimetry - DSC), optical properties (using UV-Vis spectrometry), barrier and migration in distilled water. Also, the behaviour of PLA based composites at sterilization was performed by examination the changes in their chemical structure. This study shows the feasibility of improving of PLA properties by using cellulose fibres, designed for flexible food packaging.

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In Situ Monitoring of Nitrate Content in Leafy Vegetables Using Mid-Infrared Attenuated Total Reflectance Spectroscopy coupled with Intelligent Algorithm

10.21203/rs.3.rs-20060/v1 ◽

2020 ◽

Author(s):

Fei Ma ◽

changwen Du ◽

Shuailin Zhen ◽

Yaxiao Du

Keyword(s):

Chinese Cabbage ◽

Leafy Vegetables ◽

In Situ Monitoring ◽

World Health ◽

Attenuated Total Reflectance ◽

Nitrate Content ◽

Intelligent Algorithm ◽

Mid Infrared ◽

Total Reflectance

Abstract Background: Vegetables are one of the most important nitrate sources of human diary diet. Establishing fast and accurate in situ nitrate monitoring approaches that could be used in the plant growth process and vegetable markets is essential.Results: Incorporating the unique feature of N-O asymmetric stretch absorption in the mid-infrared region (1500-1200 cm-1), portable Fourier-transform infrared attenuated total reflectance (FTIR-ATR) spectroscopic instruments, along with the Euclidean distance-modified intelligent algorithm extreme learning machine (ED-ELM) model, were employed to evaluate the nitrate contents in leafy vegetables. A total of 1224 samples of four popular vegetables (Chinese cabbage, swamp cabbage, celery, and lettuce) were analyzed. The results indicated that the nitrate contents (mean values: Chinese cabbage: 7550 mg/kg; swamp cabbage: 4219 mg/kg; celery: 4164 mg/kg; lettuce: 4322 mg/kg) highly exceeded the World Health Organization (WHO))-specified maximum tolerance limits. The ED-ELM model showed a better performance with the root-mean-square-error of 799.7 mg/kg, the determination coefficients of 0.93, the ratio of performance to deviation of 2.22, the optimized calibration dataset number of 100, and the number of hidden neurons of 30.Conclusion: The results confirmed that FTIR-ATR, along with the suitable model algorithms, could be used as a potential rapid and accurate method to monitor the nitrate contents in the fields of agriculture and food safety.

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