气相色谱-质谱法检测干辣椒中常用有机磷和拟除虫菊酯类农药的残留

摘要

目的：建立凝胶色谱技术(GPC)净化和气相色谱质谱法同时测定干辣椒中常用有机磷和拟除虫菊酯类农药的测定方法。方法样品采用乙腈-水提取，经凝胶色谱仪净化去除大分子色素及杂质，再经过石墨化炭黑-氨基SPE柱净化，以气相色谱-质谱联用仪(EI源)检测，内标法定量。结果在添加水平为0.05~0.5 mg/kg下的平均回收率为71.6%~116.4%，相对标准偏差在2.3%~10.8%之间，样品最低检出限为0.01~0.05 mg/kg。结论此方法净化效果显著，测定结果准确，实验周期短，基本实现全自动化，节省大量时间与试剂，适用于大批量辣椒的农药残留检测。%Objective A novel method was established to detect organophosphorus and pyrethroid pesticide residues in dry chillies by gel permeation chromatography (GPC) and gas chromatography mass spectrometry simultaneously.Methods The sample was extracted by acetonitrile-water, purified by GPC (dislodging macromolecular pigment as well as impurities) and an SPE graphitized carbon black-amino column, and simultaneously detected by gas chromatography-mass spectrometry (GC-MS) with internal standard method for quantification.Result The average recovery was 71.6%~116.4% at spiked level of 0.05~0.5 mg/kg and the relative standard deviation was 2.3%~10.8%. Limit of minimum detection was 0.01~0.05 mg/kg.Conclusion Compared with reported methods, this method had advantages of remarkable purification, accurate determination, short running time by full automation and fewer use of reagent. It was a powerful complement for the detection of pesticide residues for large quantities of pepper.