Analysis of oligosaccharide negative charge by anion-exchange chromatography.

This unit presents the analysis of negative charge on labeled N- or O-linked oligosaccharides. These protocols may be used in the initial screening of oligosaccharides to detect negative charge, for analytical or preparative separation of oligosaccharides based on their negative charge, or to analyze the type of negative charge found on the oligosaccharides. The basic Protocol describes the use of anion-exchange (QAE-Sephadex) chromatography with stepwise elution for estimating the number of negative charges on an oligosaccharide sample derived from glycosidase treatment of a glycoprotein. In an Alternate Protocol, gradient elution is used for the preparative separation of oligosaccharides based on negative charge. A Support Protocol describes a method for measuring loss of or change in negative charge after treatment of the oligosaccharide sample with mild acid and/or phosphatases.