Common conditions for high-performance liquid chromatographic microdetermination of aldoses, hexosamines, and sialic acids in glycoproteins.

All aldoses known to be present in animal and plant glycoproteins were separated in partition mode on a column of a highly crosslinked cation-exchange resin (Shodex DC-613, H+ form) and sensitively monitored by photometric detection after postcolumn labeling with 2-cyanoacetamide. Linearity for the sample amount ranging from 0.1 to 80 nmol was observed with high reproducibility. Hexosamines could be determined as their N-acetyl derivatives under the identical conditions with approximately one order of magnitude higher range of linearity. Sialic acid could be estimated as N-acylhexosamines produced by the action of N-acetylneuraminate pyruvate-lyase. The usefulness of these common conditions was demonstrated by analyzing component monosaccharides of some glycoprotein preparations.