Raman spectroscopy as a discovery tool in carbohydrate chemistry

Raman spectra of nine anomerically stable monosaccharides have been obtaine d in aqueous solution in the 700-1700 cm(-1) spectral range. Good-quality s pectra are obtained of solutions with concentrations as low as 10 mM and vo lumes as small as 15 mu L. Interestingly, the Raman spectra appear to be ex quisitely sensitive to the configuration of the carbon centers; unique spec tra are obtained of all nine monosaccharides. The unique Raman spectral fin gerprint observed for each monosaccharide, and for each anomer of each mono saccharide, suggests that Raman spectroscopy may be a useful technique for the identification and characterization of biologically relevant oligosacch arides. To test this idea, Raman spectra of three unknown disaccharides wer e obtained in a single-blind study. Identification of the individual monosa ccharide components and their anomeric configuration was completely success ful. All of these results suggest that development of Raman spectroscopy as a fast, sensitive discovery tool in glycobiology and carbohydrate chemistr y is straightforward.