Determination of the beta-blocker atenolol in plasma by capillary zone electrophoresis

A capillary zone electrophoretic method was optimised for the determination of the P-blocker atenolol in plasma. Separation was performed in an uncoat ed silica capillary of 58.5 cm (effective length 50 cm) X 75 mum I,D,, and detection was at 194 nm. The effects of the buffer (concentration and pH), the injection time, the voltage applied and the plasma clean-up procedure w ere studied. The determination of atenolol was achieved in less than 3 min, using an electrolyte of 50 mM H3BO3-50 mM Na2B4O7 (50:50, v/v) pH 9, injec ted hydrodynamically for 4 s at 50 mbar and applying a voltage of +25 kV. T his method was applied to the determination of atenolol in plasma of nine h ypertensive patients (male and female, aged from 39 to 73 years). Atenolol concentrations found vary from 30 to 585 ng/ml. (C) 2001 Elsevier Science B .V. All rights reserved.