title: [Determination of 107 pesticide residues in vegetables using off-line dispersive solid-phase extraction and gas chromatography-tandem mass spectrometry].
abstract: A screening method was developed for the determination of 107 pesticide residues in vegetables using off-line dispersive solid-phase extraction (DSPE) and gas chromatography-tandem mass spectrometry (GC-MS/MS). The pesticides interested were extracted from the samples with acetonitrile (saturated by n-hexane) containing 1% acetic acid and simultaneously separated by liquid-liquid partitioning with adding anhydrous magnesium sulfate plus sodium acetate following by a simple cleanup step known as dispersive solid-phase extraction. The extracts were determined by GC-MS/MS using external standard method. The method was reliable and stable that the recoveries of almost all pesticides were in the range from 60% to 130% at the spiked level of 10 microg/kg into four vegetable matrixes (garlic, green bean, radish 8 and spinach) and the relative standard deviations (RSDs) were all not more than 15.3%. The linearity of the method was good between 0.05 mg/L and 1 mg/L, and all limits of quantification (LOQs) less than 10 microg/kg. The method is selective with no interference, especially in the complicated garlic matrix.
authors: Food Laboratory of Jiangsu Entry-Exit Inspection and Quarantine Bureau, Nanjing, China. swj9722418@yahoo.com.cn
authors: Weijian
authors: W
authors: Shen
authors: Keyao
authors: K
authors: Yu
authors: Qianwen
authors: Q
authors: Gui
authors: Yuan
authors: Y
authors: Jiang
authors: Zengyun
authors: Z
authors: Zhao
authors: Chongyu
authors: C
authors: Shen
authors: Bin
authors: B
authors: Wu
authors: Xiaogang
authors: X
authors: Chu