ABSTRACT
A multi-residue analysis method was developed for the determination of 38 kinds of pesticides in nuts (almonds, peanuts, cashew nuts and walnuts) by QuEChERS-ultra-high performance liquid chromatography-tandem mass spectrometry.The pesticide residues were extracted with acetonitrile.The extract was cleaned up with PSA, C18 and Oasis PRiME HLB, and then analyzed by UPLC-MS/MS with multiple reaction monitoring (MRM) mode.External standard method was employed to quantify.The limits of detection (LODs, S/N=3) of this method were between 0.01 and 10 μg/kg, and the limits of quantitation (LOQs, S/N=10) were between 0.05-20 μg/kg.All of the tested pesticides showed good linear relationship (r>0.991).The practical samples were determined at three spiked levels and the average recoveries were between 51.0% and 126.0%.The RSDs were less than 20%.This method was simple, sensitive and accurate, and could be used for the routine analysis of pesticide residues in nuts.