FT-IR microspectroscopy

FT-IR microspectroscopy is a new nondestructive, fast and rehable technique for solid-phase reaction monitoring. It is the most powerful of the currently available IR methods as it usually requires only a single bead for analysis, thus it is referred to as single bead FT-IR [166]. (See also Chapter 12 for further details). The high sensitivity of the FT-IR microscope is achieved thanks to the use of an expensive liquid nitrogen-cooled mercury cadmium telluride (MCT) detector. Despite the high cost of the instrument, this technique should become more widely used in the future as it represents the most convenient real-time reaction monitoring tool in SPOS [166, 167]. 

Mouille, G., Robin S., Lecomte, M., Pagant S., and Hofte, H., 2003, Classification and identification of Arabidopsis cell wall mutants using Fourier-Transform InfraRed (FT-IR) microspectroscopy, Plant J. 35 393-404. 

Yan B, Gstach H, An indazole synthesis on solid phase support monitored by single bead FT-IR microspectroscopy, 37(46) 8325—8328, 1996. 

Another objective of this chapter is to introduce the use of Fourier transform infrared (FT-IR) microspectroscopy for the analysis of pigments and to provide some background about the technique. 

Samples that were organic in nature were subjected to the microchemical tests described by Hofenk-de Graaff (24) and subsequently analyzed by FT-IR microspectroscopy. 

Lasch, P., Haensch, W., Naumann, D. and Diem, M. (2004) Imaging of colorectal adenocarcinoma using FT-IR microspectroscopy and cluster analysis. Biochim. Biophys. Acta, 1688,176-86. 

LeVine, S.M. and Wetzel, D.L. (1998) Chemical analysis of multiple sclerosis Lesions by FT-IR microspectroscopy. Free Radio. Biol Med., 25, 33 1. 

D. (2005) FT-IR-microspectroscopy of prion-infected nervous tissue. Biochim. Biophys. Acta, 1758, 948-59. 

Dukor, R.K., liebman, M.N. and Johnson, B.L (1998) A new, non-destructive method for analysis of clinical samples with FT-IR microspectroscopy. Breast cancer tissue as an example. Cdl. Mol. Biol, 44, 211-17. 

Tfalyli, A., Piot, 0., Durlach, A., Bernard, P. and Manfait, M. (2005) Discriminating nevus and melanoma on paraffin-embedded skin biopsies using FT-IR microspectroscopy. Biochim. Eiophys. 

The spatial resolution of FT-IR microspectroscopy, without sacrificing spectral quality and resolution, makes imaging possible. Shortly after the introduction of the first research-quality IR microscope by Messerschmidt and Sting in 1986, Wetzel, Messerschmidt and Fulcher reported spectra obtained from wheat kernel transverse sections in situ, and compared them with flour milling fractions [7]. This was achieved with an accessory IR-PLAN microscope optically interfaced to a Nicolet interferometer bench. Subsequently, at the Agriculture Canada laboratory the same model IR-PLAN was interfaced to a Bomen Michelson IR 100 spectrometer such that, over the period of a year, transverse sections of wheat kernels, vanilla beans, peppercorns and soybeans were manually line-mapped to reveal any differences in microchemical structural characteristics between their different botanical parts [8]. 

In the field of animal science, FT-IR microspectroscopy has been used to Unk animal feed performance (ruminant digestion) to locaUzed chemical distributions within specific corn, barley and canola varieties [43, 44]. A potential solution for remediating chemicals encountered environmentaUy in contaminated soil is to grow plants capable of mining such chemicals. As an example, sunflower stalks grown hydroponically were imaged by IMS to first locate, and then determine the relative uptake of, these materials [45]. The same group also reported selected... 

In situ FT-IR microspectroscopy and mapping of normal brain tissue. Spectroscopy, 8 (4), 40-5. 

Wetzel, D.L and Williams, G.P. (1998) Localized (5 mm) probing and detailed mapping of hair with synchrotron powered FT-IR microspectroscopy, in Proceedings, nth International Conference on Fourier Transform Spectroscopy, Athens, Georgia, August 1997 (eds J.A. deHaseth and R.A. Dluhy), American Institute of Physics, Woodbury, New York. 

Yu, P., Christensen, C.R., Christensen, D.A. and McKinnon, J.J. (2005) Ultrastructural-chemical makeup of yellow- and brown-seeded Brassica canola within cellular dimensions, explored with synchrotron reflection FT-IR microspectroscopy. Can. J. Plant ScL,... 

Wetzel, D.L. and LeVine, S.M. (1998) Fourier transform infrared (FT-IR) microspectroscopy a new molecular dimension for tissue or cellular imaging dimension for tissue or cellular imaging and in situ chemical analysis. Cell. Mol Biol, 44 (1), 1-280. 

Additional techniques such as FT-IR microspectroscopy, IR and Raman spectroscopy, NMR, and energy dispersive x-ray, in conjunction with scanning electron microscopy, inductively coupled plasma, etc., may also be utilized to provide additional pieces of information toward the comprehensive analysis of materials and the identification of unknowns. Although HSM may not be a technique that all laboratories require, it is clear that the technique can provide valuable information for the visual confirmation of thermal transitions. 

TP Abbott, PC Felker, and R Kleiman. FT-IR Microspectroscopy Sample Preparation and Analysis of Biopolymers. App/. Spectrosc. 47 180-189, 1993. 

Y Kataoka and M Kiguchi. Depth Profiling of Photo-Induced Degradation in Wood by FT-IR Microspectroscopy. J. Wood Sci. 47 325-327, 2001. 

Variable-temperature studies may also be performed with FT-IR microspectroscopy. Through the use of an environmentally controlled chamber, small... 

Xuguang, S. (2005). The investi tion of chemical structure of coal macerals via transmitted-light FT-IR microspectroscopy. SpectrodiimActa, Vol.62, pp. 557-564. 

Special issue on FT-IR microspectroscopy, Cell Mol. Biol. 44 (February 1998). 

Panayiotou H and Kokot S (1999) Matching and discrimination of single human - scalp hairs by FT-IR microspectroscopy and chemometrics. Analytica Chimica Acta 392 223-235. 

Robotham, C. Izzia, F. FT-IR Microspectroscopy in Forensic and Crime Lab Analysis. Application Note 51517, Thenno Fisher Scientific, Inc. Madison, WI, 2008. 

I. Mitri, E Kenig, S Coceano, G Bedolla, D.E., Tormen, M Grenci, G., Vaccari, L. (2015) Time-Resolved FT-IR Microspectroscopy of Protein Aggregation Induced by Heat-Shock in Live Cells. Anal. Chem. 87 3670-3677. 

The first question can almost always be answered by PLM, and often more specifically by FT-IR microspectroscopy, regardless of how httle fiber is available. The other four may often be more difficult. 

Uses of FT-IR microspectroscopy include general characterization of particulate matter, dichroic measurements with polarized light, polymer characterization. semiconductor measurements, the identification of contaminants, as well as forensic, biological, and pharmaceutical applications [157]-11.59). 

This technique has been used for the identification of undispersed particles in plastic applications. It is particularly useful for resolving customer complaints as well as process development problems. As a general rule particles 20 microns or larger can be analyzed by FT-IR spectroscopy. The approach is to focus the IR beam onto the particle of interest using the microscope, and then scan the FT-IR spectra several times (100 scans), either in transmission or reflectance mode. The sample is then moved slightly to another position and the microscope is focused on a portion of the sample without a defect. The FT-IR spectrum of this part of the sample is recorded in exactly the same way as that of the defective part. The spectrum of the non-defective part is then subtracted from spectrum of the defective part of the sample. The difference spectrum is then used to identify the spot or particle in the defective part. Optical microscopy is often used together with FT-IR microspectroscopy to aid in selecting the area of interest to be analyzed. 

R. Manoharan, J. J. Baraga, R. P. Rava, R. R. Dasari, M. Fitzmaurice and M. Feld, Biochemical analysis and mapping of atherosclerotic human artery using FT-IR microspectroscopy. Atherosclerosis, 1993, 103, 181-193. 

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