Multi-Residue Determination Of Veterinary Drugs In Porcine Muscle By Quechers And Liquid Chromatography-Tandem Mass Spectrometry

A liquid chromatography-tandem mass spectrometric method with modified QuEChERS procedure for sample preparation was developed for the simultaneous determination of 7 classes of 35 veterinary drugs including sulfonamides, sulfonamide potentiators, beta-agonists, tetracyclines, amnatadine and sex hormones in porcine muscle. The drugs were extracted with 0.1 mol/L Na(2)EDTA (ethylene diamine tetraacetic acid)-Mcllvaine buffer solution and acetonitrile containing 2.5% (v/v) acetic acid, and then the extracts were purified using dispersive-solid phase extraction with NH2 sorbent, and finally analyzed by liquid chromatography-tandem mass spectrometry in multiple reaction monitoring mode via positive electrospray ionization. The correlation coefficients of the standard calibration curves for the 35 veterinary drugs were all above 0.996. The blank samples were spiked at three levels, and the average recoveries ranged from 71.8% to 113.5% with the relative standard deviations from 0.6% to 9.8% (n=6). The limits of detection and the limits of quantification were 0.01-1.01 mu g/kg and 0.04-3.37 mu g/kg respectively. The method developed is easy to operate, sensitive, with good purification effect and suitable for the determination of residues in porcine muscle.