SURFACE-ENHANCED RAMAN-SCATTERING SPECTRO SCOPY OF SIALOSIDES AND THEIR DERIVATIVES

The spectra of the surface-enhanced Raman scattering (SERS) of some gl ycosides of N-acetylneuraminic acid and their derivatives, including a lpha-benzyl glycoside, beta-benzyl glycoside, alpha-methyl glycoside, methyl ester of alpha-benzyl glycoside, alpha-benzyl glycoside of N-tr ifluoroacetylneuraminic acid, and alpha-benzyl glycoside of 4-epi-N-ac etylneuraminic acid, were analyzed. The assignment of the bands appear ing in the SERS spectra was made. It was shown that for adsorption on the SERS-active surface, carboxylic, N-acetyl, and hy droxyl groups of the glycerol residue of sialic acid are important. A correlation betw een the intensity of the SERS spectra of sialosides and their binding together with hemagglutinin of the influenza virus was found. It was p roposed that the conformations of sialosides in the complex with hemag glutinin and upon the adsorption at the SERS-active surface are simila r, which explains this correlation. Surface characteristics that deter mine a given type of the sialoside adsorption were considered.