Analysis of 11 β-Agonist Residues in Liver, Kidney and Meat by Gas Chromatography-Mass Spectrometry

The method for the determination of β-agonist residues in liver, kidney and meat by gas chromatography-mass spectrometry (GC/MS) has been developed. The sample was extracted in acetate buffer of pH5.2 and the extraction was hydrolyzed by β-glucuronidase/arylsulfatase, then the protein was precipitated with perchloricacid. The supernatant was passed through a SCX cation-exchange column and derivatized with N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). With metoprolol as internal standard, eleven β-agonists were determined at one time. The experimental results from of spiked liver, kidney and meat sample inditated that the average recoveries ranged from 71% to 94%, the variation coefficient was 4.6%-18.7%, the limits of detection (LODs) were 0.002-0.005 mg/kg.