加速溶剂萃取-在线凝胶渗透色谱-气相色谱-质谱联用法快速测定蔬菜和水果中多农药残留

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0.9981),检出限(以信噪比(S/N)为3计算)为0.3～1.8 μg/kg,定量限（S/N=10）为1~6 μg/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。

Rapid determination of pesticide multiresidues in vegetables and fruits by accelerated solvent extraction coupled with online gel permeation chromatography-gas chromatography-mass spectrometry

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-acetone(1∶1,v/v) and purified with a carbon/NH2 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 0.3-1.8 μg/kg.The limits of quantification(S/N=10) ranged from 1-6 μg/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.