Determination Of 35 Kinds Of 7 Categories Of Veterinary Drugs Residues In Pork By QuEChERS-UPLC-MS

Objective:To establish the UPLC-MS detection method of 35 kinds of 7 categories of veterinary drugs residues in pork,and provide technical support for the screening and monitoring of multi veterinary drug residues in pork.Methods:The pork samples were extracted with Na2EDTA-Mcllvaine(pH4.0)and 2.5%acetic acid acetonitrile,and then were purified and concentrated by QuEChERS method for using the dehydrating agent of NaCl and anhydrous Na2S04 and the adsorbent of-NH2,followed by ultra performance liquid chromatography-mass spectrometry analysis.The compounds were separated by using the mobile phase of 0.1%formic acid solution-0.1%formic acid in acetonitrile,and were detected in electrospray ionization in positive ion mode with the method of multiple reaction monitoring(MRM),The analyzer confirmed and quantified by Matrix spiked blank curve external standard method.Results:The linear ranges of the 35 kinds of veterinary drugs are 0.5?50ng/ml and the correlation coefficients were greater than 0.995,The average recovery rate of 4 different concentrations were 60?110%,Relative deviation(RSD)were less than 10%,The detection limit(LOD,S/N=3:1)were 0.02?1.2?g/kg,The quantitative limit(LOQ,S/N=10:1)were 0.07?4.0?g/kg.Conclusion:The method is simple,rapid,reliable,sensitive and efficient,and can be used for the detection and monitoring of multi drug residues in pork.