High-performance liquid chromatography of sialic acid-containing oligosaccharides and acidic monosaccharides.

Many sialic acid-containing oligosaccharides and five acidic monosaccharides have been separated by high-performance anion-exchange chromatography using a Dionex AS6 ion-exchange column eluted with aqueous 50 mM NaOH plus 50-175 mM sodium acetate. Using a pulsed amperometric detector, as little as 50 pmol oligosaccharide can be detected. Many factors, such as the presence of fucosyl groups or sialyl groups, glycosidic linkage positions, and branching structure, can have a tremendous influence on overall acidity of the oligosaccharide, which can lead to excellent separations and make this method an important addition to existing alternatives for the separation of sialic acid-containing oligosaccharides.