OPTIMIZATION OF THE SEPARATION OF BETA-AGONISTS BY CAPILLARY ELECTROPHORESIS ON UNTREATED AND C-18 BONDED SILICA CAPILLARIES

The conditions of the separation of ten beta-agonists by capillary zon e electrophoresis were studied. Several buffers were tested at differe nt ionic Strengths and different pH values. The experiments were carri ed out on two different supports, i.e. an untreated fused-silica capil lary and a C-18 covalently bonded silica capillary. The results showed that the optimum pH value was the same for the two capillaries. Separ ation efficiencies were slightly better for the fused-silica capillary whereas better selectivity and repeatability were obtained with the C -18 bonded capillary, under optimal conditions.