Enantioselective Separation of Basic Drugs by CE with Polygalacturonic Acid as a Novel Chiral Selector

Polygalacturonic acid, a linear high molecular weight homopolysaccharide was investigated as a chiral selector in capillary zone electrophoresis for the separation of enantiomers of basic drugs. The choices of running buffer pH and concentration of chiral selector were found to be important for the improvement of enantioselectivity. The effects of background electrolyte concentration and the capillary temperature on the separation were also examined. Enantioseparations were carried out in the acidic conditions using 1.5% polygalacturonic acid (w/v) in a 40 mM phosphate buffer under an applied voltage of 15 kV. The optimization of these separations was dependent on the nature of the analytes and could be achieved by the proper choice of experimental conditions. A brief mechanism of enantiorecognition by polygalacturonic acid was also given.