Separation of complex oligosaccharide mixtures by capillary electrophoresis in the open-tubular format.

The fluorescent derivatives of complex oligosaccharide mixtures from different origins are separated in open capillaries. The number of negatively charged sulfonate groups in the tag molecule strongly affects separation efficiency and selectivity. Coating of the capillary surface with linear polyacrylamide has been essential to ensure fast and stable migration velocities. Efficiencies in excess of 1 million plates/m have been achieved, facilitating resolution of branched oligosaccharides. The effects of field strength and buffer composition on the apparent electrophoretic mobility of dextran and dextrin oligomers are discussed, with relation to borate complexation. Preliminary examples of applications to monitoring the action of hydrolytic and synthesizing enzymes are also described.