Simultaneous detection of residues of beta-adrenergic receptor blockers and sedatives in animal tissues by high-performance liquid chromatography/tandem mass spectrometry

A method using high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) was developed to screen and confirm residues of multi-class veterinary drugs in animal tissues (porcine kidney, liver, muscle; bovine muscle). Thirty target drugs (19 beta-blockers, 11 sedatives) were determined simultaneously in a single run. Homogenized tissue samples were extracted with acetonitrile and purified using a NH2 solid-phase extraction cartridge. An Acquity UPLC (TM) BEH C18 column was used to separate the analytes. followed by tandem mass spectrometry using an electrospray ionization source in positive mode. Recovery studies were done at three fortification levels. Overall average recoveries in pig muscle, kidney, and liver fortified at three levels from 76.4% to 118.6% based on matrix-fortified calibration with coefficients of variation from 2.2% to 19.9% (n = 6). The limit of quantification of these compounds in different matrices was 0.5-2.0 mu g/kg. This method was successfully applied in screening and confirming target drugs in >200 samples. (C) 2009 Elsevier B.V. All rights reserved.