SEPARATION OF GLYCOSAMINOGLYCAN-DERIVED OLIGOSACCHARIDES BY CAPILLARYELECTROPHORESIS USING REVERSE POLARITY

A comparative study on compositional analysis of two sets of eight uns aturated disaccharide standards derived from heparin/heparan sulfate a nd chondroitin/dermatan sulfate was carried out using capillary electr ophoresis performed in both normal and reverse polarity modes. While t hese heparin/heparan sulfate disaccharides (S. A. Ampofo, H. M. Wang, and R. J. Linhardt (1991) Anal. Biochem. 199, 249-255) and chondroitin /dermatan sulfate disaccharides (A. Al-Hakim and R. J. Linhardt (1991) Anal. Biochem. 195, 68-73) have previously been fractionated using no rmal polarity capillary electrophoresis, multiple buffer systems and c onditions were required to separate certain disaccharide isomers and t hese separations often resulted in poor peak symmetry and significant tailing. This paper demonstrates that reverse polarity capillary elect rophoresis completely resolves disaccharide mixtures into all componen ts using a single buffer, 20 mM phosphoric acid-sodium phosphate at pH 3.48. This improved resolution is due primarily to an increase in the sharpness of peaks and improved peak symmetry. Separation of heparin- derived oligosaccharides, ranging from disaccharide to hexasaccharide, had also previously been reported using normal polarity capillary ele ctrophoresis (U. R. Desai, H. M. Wang, S. A. Ampofo, and R. J. Linhard t (1993) Anal. Biochem. 213, 120-127). This paper now demonstrates the separation of 13 heparin-derived oligosaccharides of sizes ranging fr om disaccharide to tetradecasaccharide using both reverse and normal p olarities. An enzymatic digestion of bovine lung heparin containing ma ny of these larger oligosaccharides was also compared in both normal a nd reverse polarity modes. Mixtures containing oligosaccharides primar ily differing in size (number of saccharide units) were better resolve d using normal polarity. (C) 1994 Academic Press,Inc.