增强型去除脂质技术结合气相色谱-三重四极杆串联质谱法检测水产饲料中45种除草剂和杀虫剂农药残留

Simultaneous determination of 45 herbicides and insecticides in aquatic feeds by enhanced matrix removal-lipid coupled with gas chromatography-triple quadrupole-tandem mass spectrometry

本实验旨在建立增强型脂质去除(EMR-lipid)技术结合气相色谱-三重四极杆串联质谱(GC-MS/MS)同时检测饲料中的45种除草剂和杀虫剂农药残留的测定方法,优化了仪器参数、提取试剂、样品净化方式、增强型脂质去除吸附剂活化用水的体积和N-丙基乙二胺(PSA)吸附剂添加量和样品的基质效应等,实验选用低流失的DB-5MS气相色谱柱,超高惰性的453A1925-UI石英棉衬管,采用1%的乙酸乙腈超声提取、EMR-lipid和PSA混合吸附剂净化,EMR-lipid吸附剂活化用水的体积为5 mL,PSA吸附剂的用量为0.12 g,用气相色谱串联质谱,多反应监测(MRM)模式检测,基质匹配外标法定量。结果表明:在该实验条件下,45种农药在10~500μg/L内均呈现出良好的线性关系,相关系数为0.9911~0.9999,方法的检出限为0.5~3.3μg/kg,定量限为1.7~10.1μg/kg,除了杀扑磷回收率为58.01%~59.27%外,其他项目的回收率为68.34%~114.7%,方法精密度(RSD)为0.7%~11.0%(n=6),该方法的净化效果及检出限等指标均优于现行的饲料检测标准,将该方法用于分析市场上30份饲料样品中45种农药的残留污染情况,结果显示,有3份样品中3种农药被检出,分别是毒死蜱8.3μg/kg、阿特拉津10.1μg/kg、氟乐灵20.1μg/kg,该方法样品操作简单、灵敏度高、重复性好、环境友好,可用于饲料中多种农药残留的快速定量检测。

The aim of this experiment was to establish a method for simultaneous determination of 45pesticide residues,which include herbicides and insecticides,in aquatic feed using gas chromatography-triple quadrupole mass spectrometry(GC-MS/MS) coupled with enhanced matrix removal-lipid.Optimized instrumental parameters,extraction reagents,purification method,volume of activated water for enhanced matrix removal-lipid(EMR-Lipid),addition of primary secondary amine(PSA),and matrix effect of sample.The optimal pretreatment process was finally determined as follows:The DB-5MS gas chromatographic column with low loss and the 453A1925-UI quartz liner with ultra-high inertia were selected.The sample was extracted with 1% acetate acetonitrile,cleaned-up by dispersive solid-phase extraction using EMR-lipid dispersant sorbent and PSA sorbent,the optimal volume of activated water was 5 mL,the amount of PSA adsorbent was 0.12 g,detected by gas chromatography-triple quadrupole mass spectrometry,multiple reaction monitoring(MRM)mode,the matrix matching calibration and external standard method were used for quantitation.The results showed that the 45 pesticide residues had good linear relationships in the range of 10to 500 μg/L,with correlation coefficients between 0.9911 and 0.9999,The detection limit(LODs) of the method were 0.5 ~ 3.3 μg/kg,and the limit of quantitation(LOQs) were 1.7 ~ 10.1 μg/kg,the recovery was between 68.34% and 114.7% except methidathion with recovery between 58.01% and 59.27%,the relative standard deviations(RSDs,n=6) was 0.7% ~ 11.0%.The purification effect and detection limit of method were superior to current standard for feed detection.30 samples of various feed matrices were analyzed sold on market,the result suggested that 3 target pesticides were positive in 3 samples,the positive pesticide were chlorpyrifos,atrazine and trifluralin with content of 8.3,10.1,20.1 μg/kg separately.The method was simple operation,high sensitivity,good repeatability and environment-friendly,and could be used for simultaneous rapid quantitative detection of 45 herbicides and insecticides residues in feed.