Determination of beta-agonists in pig feed, pig urine and pig liver using capillary electrophoresis with electrochemical detection.

The fast separation capability of a capillary electrophoresis with electrochemical detection (CE-ED) system was demonstrated by determining five beta-agonists including clenbuterol, metoprolol, ractopamine, isoxsuprine and salbutamol in several real samples. Factors influencing the separation and detection were examined and optimized. Under the optimum conditions, the five beta-agonists could be well separated within 15min at a separation voltage of 14kV in a 100mmoL H(3)BO(3)-Na(2)B(4)O(7) running buffer (pH 9.0). This method was successfully used in the analysis of clenbuterol, metoprolol, ractopamine, isoxsuprine and salbutamol in pig feed, pig urine and pig liver, providing a useful method for monitoring the illegal use of beta-agonists from growth promotion in food-producing animals. Copyright 2010 Elsevier Ltd. All rights reserved.