Separation and determination of clenbuterol, cimaterol and salbutamol by capillary electrophoresis with amperometric detection

Capillary electrophoresis with amperometric detection was applied to determine some beta(2)-agonists, such as clenbuterol, cimaterol and salbutamol in this paper. The working electrode used was a 0.3 mm diameter carbon disk electrode. In this work, the pH 6.0 - 6.4 borax-potassium dihydrogen phosphate was used as running buffer (150 mmol/L), 10 kV as the separation voltage and 1.05 V (vs. Ag/AgCl, 3 mol/L KCl) as the detection potential. Under the optimum conditions, the analytes were baseline separated within 16 min. Linear range for cimaterol, clenbuterol and salbutamol was 1.0-2000, 2.0-2000 and 1.0-2000 ng/mL, respectively. The detection limits (define as 3 sigma/k) were 0.5, 1.0 and 0.4 ng/mL for cimaterol, clenbuterol and salbutamol, respectively. The developed method has been applied to determine these three analytes in feed and urine by standard addition. The mean recoveries for these three analytes ranged from 89.0% to 102.0%.