Linear, neutral polysaccharides as chiral selectors in enantioresolution of basic drug racemates by capillary electrophoresis

A comparison of the enantiorecognition ability of linear, neutral polysaccharides was performed on a series of basic drug racemates in acidic running buffer (pH 3.0). Dextrin 20, Dextran 70 and Pullulan were chosen as chiral selectors for their different characteristics. Dextrin 20, high-dextrose equivalent maltodextrin, showed good enantioresolution for a limited number of racemic drugs. In contrast, Dextran 70, a low-equivalent dextrose polysaccharide, exhibited poorer enantioresolution but had wider applicability allowing nine basic racemates to be resolved; in particular, at high concentrations enantioseparation of amphetamine and congeners was achieved in relatively short time. The results obtained appear to support different mechanisms of enantiorecognition for the polysaccharides studied.