CAPILLARY ZONE ELECTROPHORETIC SEPARATION OF BETA-BLOCKERS USING CITRATE BUFFER AT LOW PH

Ten beta-blockers were simultaneously separated by capillary zone elec trophoresis using citrate buffer as a background electrolyte at low pH . The effects of buffer concentration and buffer pH on the migration b ehavior and separation of beta-blockers were systematically investigat ed. The results indicate that the resolution of co-migrating analytes improves with increasing buffer concentration at a low pH and that the optimum pH of the buffer decreases with increasing buffer concentrati on. Complete separation of the beta-blockers tested was achieved withi n a relatively short time with an appropriate concentration of citrate buffer in the range 160-400 mM and a proper pH in the range 3.0-1.8 u sing a 43 cm x 50 mu m I.D. fused-silica capillary at 15 kV.