A novel method was developed for the rapid determination of 22 representative pesticide residues in vegetables and fruits based on accelerated solvent extraction (ASE) coupled with online gel permeation chromatography-gas chromatography-mass spectrometry ( GPC-GC-MS). The sample was extracted by accelerated solvent extraction with dichloromethane-ace-tone (1:1 , v/v) and purified with a carbon/NH;column, evaporated to dryness by nitrogen, then dissolved in cyclohexane-acetone (7:3, v/v), and finally identified and quantified by GPC-GC-MS system in selected ion monitoring (SIM) mode. The results showed that the linearities of the 22 pesticides were good in their linear ranges. The limits of detection (S/N = 3 ) were 0. 3 - 1. 8μg/kg. The limits of quantification (S/N =10) ranged from 1 -6 jig/kg. The recoveries for all at three spiked levels in Chinese cabbages and apples ranged from 70. 5% to 107. 5% with the relative standard deviations (RSDs) of 2.1% - 8.7%. The proposed method is accurate, sensitive and highly efficient in the extraction, and can be used for the quick determination of the pesticide multiresidues in vegetables and fruits.%建立了加速溶剂萃取-在线凝胶渗透色谱-气相色谱-质谱联用(GPC-GC-MS)快速测定蔬菜、水果中代表性农药残留的检测方法.样品经二氯甲烷-丙酮(1∶1,v/v)加速溶剂提取,活性炭柱-氨基柱串联净化,氮吹至干,残留物用环己烷-丙酮(7∶3,v/v)溶解后经GPC-GC-MS系统以选择离子监测(SIM)模式测定.结果表明,22种农药在各自的线性范围内线性关系良好(相关系数不低于0.998 1),检出限(以信噪比(S/N)为3计算)为0.3～1.8μg/kg,定量限(S/N=10)为1～6μg/kg.在2种基质(大白菜、苹果)中3个添加水平下的回收率为70.5％ ～107.5％,相对标准偏差为2.1％ ～8.7％.该方法提取效率高,定性定量准确、灵敏,可实现对蔬菜、水果中多农药残留的快速检测.
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