Separation and determination of beta-agonists in serum by capillary zone electrophoresis with amperometric detection

A simple, reliable and reproducible method, based on capillary zone electro phoresis with amperometric detection, for separation and determination of b eta -agonists, namely adrenaline, salbutamol and salmeterol in serum was de scribed in this paper. A carbon-disk electrode was used as working electrod e. The optimal conditions of separation and detection were pH 6.6 phosphate buffer solution (0.06 mol/l), 12 kV for the separation voltage and 0.85 V (versus Ag/AgCl) for the detection potential. The linear ranges were from 1 .0 x 10(-7) to 1.0 x 10(-5) mol/l for adrenaline, 3.0 x 10(-7) to 5.0 x 10( -5) mol/l for salbutamol, and 5.0 x 10(-7) to 8.0 x 10(-5) mol/l for salmet erol with the correlation coefficient of 0.998, 0.998 and 0.992, respective ly. The detection limits for adrenaline, salbutamol, and salmeterol were 5. 0 x 10(-8), 2.0 x 10(-7) and 2.0 x 10(-7) mol/l (based on the signal to noi se ratio of 3). The method built in this paper was directly applied to the determination of beta -agonists in the spiked serum without any other sampl e pre-treatment except filtration, and the assay results were satisfactory. (C) 2001 Elsevier Science B.V. All rights reserved.