QuEChERS-气相色谱-三重四级杆质谱法检测石榴中的19种含磷农药残留

Determination of 19 organophosphorus pesticide residues in pomegranates using QuEChERS coupled with gas chromatography-triple quadrupole mass spectrometry

采用Qu ECh ERS前处理方法联合气相色谱串联三重四级杆质谱法(gas chromatography-triple quadrupole mass spectrometry,GC-MS/MS),建立了同时测定石榴中19种有机磷农药残留的分析方法。使用优化后的Qu ECh ERS方法对石榴进行前处理,选用乙酸乙酯为提取剂、N-丙基乙二胺(primary secondary amine sorbent,PSA)为净化剂,经Rtx-5MS色谱柱分离后在多反应监测模式(multiple reaction monitoring mode,MRM)下进行测定。结果表明:该方法在0. 01～1. 0 mg/L的线性范围内线性关系良好,相关系数(r)均大于0. 99,最低检出限(S/N=3)为0. 9～3. 7μg/kg,定量限(S/N=10)为3～12. 2μg/kg,加标回收率为73. 5%～120. 9%,相对标准偏差(RSD)为1. 1%～15. 7%。利用该方法对市售石榴进行有机磷农药进行检测,其中检出微量的久效磷和乐果2种农药。该方法快速、准确、灵敏度高,适用于石榴中有机磷农药的多残留检测。

QuEChERS and gas chromatography-triple quadrupole mass spectrometry were adopted as an efficient method to detect and analyze nineteen organophosphorus pesticide residues in pomegranates.The sample was prepared by optimized QuEChERS,extracted with ethyl acetate and purified by primary secondary amine sorbent(PSA)adsorbent.The nineteen organophosphorus pesticide residues were separated by an Rtx-5MS column,and determined using MS/MS in multiple reactions monitoring mode.All correlation coefficients of calibration curves were over 0.99 in the linear concentration range 0.01-1.0 mg/L.The detection limit(S/N=3)was 0.9-3.7μg/kg,and the quantitation limit(S/N=10)was 3-12.2μg/kg.The recovery rate was 73.5%-120.9%with relative standard deviations(RSDs)between 1.1%and 15.7%.Two kinds of pesticides,monocrotophos and dimethoate,were detected from pomegranates available from the market by this method.This method proved to be rapid,accurate,and with high sensitivity.It can be applied for simultaneous determination of organophosphorus pesticide residues in pomegranates.