A multi-residue method for the determination of 124 pesticides in rice by modified QuEChERS extraction and gas chromatography-tandem mass spectrometry

A modified QuEChERS method for simultaneous determination of 124 pesticide residues in rice was established and validated. The rice samples were initially extracted with acetonitrile (MeCN), and the targeted pesticides were purified following the dispersive solid phase extraction (d-SPE) cleanup method and detected by gas chromatography-tandem mass spectrometry (GC-MS/MS). The efficiency of citrate-buffered and unbuffered method in liquid extraction procedure was compared; the amount of primary secondary amine (PSA) was optimised. In the method validation, correlation coefficients (r(2)) were higher than 0.990 with the linear ranging from 10 to 200 mu g kg(-1). At the fortification levels of 20-200 mu g kg(-1), average recoveries ranged from 70% to 122.7% with the RSD <20%. (C) 2012 Elsevier Ltd. All rights reserved.