Chiral separations using heparin and dextran sulfate in capillary zone electrophoresis

The utility of heparin and dextran sulfate as chiral mobile phase additives for the enantioresolution of chloroquine and chlorpheniramine in capillary zone electrophoresis was explored. Factors shown to affect the resolution of these analytes include pH, concentration of the buffer, concentration of the chiral additive and the molecular weight of the additive. In the presence of 2% heparin, optimized baseline resolution for chloroquine required 10 mM phosphate buffer, pH 6.0 while chlorpheniramine required pH 5.0. Similar conditions were required when using dextran sulfate although the best resolution for chlorpheniramine required 50 mM phosphate buffer.