Separation and Determination of β 2-Agonists in Swine Feed Using Field-Amplified On-Line Sample Stacking Method by Capillary Zone Electrophoresis

Abstract

A rapid, simple, and reliable capillary zone electrophoresis method was developed for the separation and determination of β2-agonists under the optimum buffer solution consisting of 50 mM H3BO3-Na2B4O7 and 30 mM NaCl (pH 7.40). The field amplified sample stacking (FASS) technique was applied to the on-line concentration of β2-agonists cimaterol, clenbuterol, and salbutamol. The data presented in this work indicate that the sensitivity could be improved significantly by using a short water plug in FASS. Under the optimum conditions, cimaterol, clenbuterol, and salbutamol were separated completely and determined with the correlation coefficient of 0.9996 ∼ 0.9999. The relative standard deviations (RSD) were less than 2.85% (run to run) and 3.10% (day to day) for peak area. The detection ranges (S/N = 3) were located from 0.01 to 1 µg/mL for each β2-agonists. With this stacking measure, cimaterol, clenbuterol, and salbutamol in spiked swine feed were successfully determined with the recovery more than 95%.