Polysaccharides Fourier-transform infrared spectroscopy

Structural study of polysaccharides and other carbohydrates in solution or in the amorphous state has been significantly enhanced through the application of Fourier-transform, infrared spectroscopy. Among the advantages of this method may be mentioned the high quality of the spectra, and the in-house ability to interact with the computer, so that the digitized spectra may be stored and manipulated in such a way that additional information is obtained. The application of F.t.-i.r. spectroscopy in the field of carbohydrate chemistry and biochemistry is still in its infancy,182 but... 

After their isolation by chromatographic techniques (anion-exchange chromatography, size exclusion, etc.), different analytical methodologies have been used to identify and quantify the polysaccharides in wine the most commonly used being the traditional methylation analysis followed by GC-MS (Doco and Bril-louet 1993). Polysaccharides have also been determined after solvolysis with anhydrous methanol containing HCl by GC-MS of their per-G-trimethylsilylated methyl glycosides (Vidal et al. 2003). Other techniques such as Fourier transform infrared spectroscopy (FTIR) have been more recently proposed (Coimbra et al. 2002,2005 Boulet et al. 2007). 

Boulet, J.C., Williams, P., Doco, T. (2001). A Fourier transform infrared spectroscopy study of wine polysaccharide. Carbohydr. Polym., 69, 79-85. 

A recent publication [41] related to this process describes that 1° O—H bond are cleaved to generate the free radical sites. Fourier-transform infrared spectroscopy (FTIR) confirmed that free radicals are formed on polysaccharide backbone by cleavage of 1°—OH bond, indicating that free radicals are generated by means of microwave effect and not due to thermal decomposition. 

MA Coimbra, F Goncalves, AS Barros, I Delgadillo. Fourier transform infrared spectroscopy and chemometric analysis of white wine polysaccharide extracts. J Agric Food Chem 50 3405-3411, 2002. 

Fourier transform infrared (FTIR) spectroscopy is an important analysis technique for determining the composition, chemical structure, and branching in some pol5miers. FTIR spectroscopy is used to investigate the molecular vibrations and polar bonds between different atoms. Structures of polysaccharides, such as monosaccharide types, glucosidic bonds, and functional groups, can be analyzed using FTIR spectroscopy. 

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