The authors investigated the usefulness of preferential partial acetolysis of the a1? linkages in establishing homogeneity and branching of the oligosaccharide. The Et ester of p-aminobenzoic acid has been used to derivatize the reducing termini of intact carbohydrates. The HPLC is effective to separate the trace products of acetolysis. After determing the mol. wts. using neg. ion LSIMS, the branching can be characterized easily. using pos. ion LSIMS. The a1? linkages of isomaltooctaose have been determine satisfactorily using the advanced acetolysis. The branching of a high mannose oligosaccharide isolated from IgM was determine at micromole level.

Key words: BENZAMINE P, HIGH SPEED LIQUID CHROMATOGRAPHY, ETHYL ESTER, BENZENECARBOXYLIC ACID P, ION CHROMATOGRAPHY, OLIGOSACCHARIDE