ABSTRACT
I. INTRODUCTION The emergence of glycoproteins as pharmaceutical products made it neces sary to develop fast, high resolution, and reproducible methods for the analysis of complex carbohydrates [1,2]. Due to the increasing evidence that carbohydrate moieties of glycoproteins are important as recognition factors in receptor-ligand or cell-cell interactions, in immunogenicity mod ulation, in the folding/unfolding process of protein molecules, and in the regulation of protein bioactivity, understanding the role of glycoproteins in the function of normal and abnormal cells is increasingly important [3]. Even small changes in the oligosaccharide structures and/or site occupancy can significantly influence the biological activity of glycoproteins. The wide variety of similar structures of oligosaccharides in glycoproteins have made it difficult to obtain all the necessary information to address the foregoing problems. With the advent of high performance capillary gel electrophore sis (HPCGE) in conjunction with the ultrasensitive detection capability of the laser-induced fluorescence (LIF) systems, faster and higher resolution separations enable the tentative identification of small quantities of closely related complex oligosaccharides [4-8]. Using this novel methodology, indi vidual oligosaccharides can be quantified to obtain molar ratios, and to detect changes in the extent and nature of glycosylation [9,10].
