QuEChERS/气相色谱-串联质谱法测定乳制品中232种农药残留

Determination of 232 Pesticide Residues in Dairy Products by Gas Chromatography-Tandem Mass Spectrometry

建立了气相色谱-串联质谱(GC-MS/MS)同时测定6种乳制品中232种农药残留的检测方法。样品经1%乙酸乙腈提取后,加入无水醋酸钠和无水硫酸镁液液分离,然后加入无水MgSO4、C18和N-丙基乙二胺(PSA)进行分散固相净化,上清液经氮吹浓缩复溶后,结合气相色谱-串联质谱测定,用多反应离子监测(T-MRM)模式进行检测,基质匹配内标法定量。结果显示:232种农药线性关系良好,相关系数均大于0.99,方法的定量下限为0.0004~0.05 mg/kg,在0.01、0.02、0.10 mg/kg加标水平下的平均回收率为65.2%~110%,相对标准偏差(RSD)为3.6%~13%。该方法样品处理简单快速,相比其他多残留分析方法净化效果好,灵敏度和选择性高,适用于日常检测工作。

A gas chromatography-tandem spectrometric(GC-MS/MS)method was developed for the rapid determination of 232 pesticide residues in six kinds of dairy products.The samples were extracted with acetonitrile containing 1%acetic acid,then separated by liquid-liquid extraction with anhydrous sodium acetate and anhydrous magnesium sulfate,and followed by dispersive solid phase purification using anhydrous magnesium sulfate,C18 and PSA.The supernatant was concentrated under nitrogen,redissolved,then analyzed by GC-MS/MS under multiple reaction mode(T-MRM),and finally quantified by matrix matched internal standard method.Results showed that there existed good linear relationships for 232 pesticides with correlation coefficients more than 0.99.The limits of quantitation(LOQ)were in the range of 0.0004-0.05 mg/kg.The spiked recoveries at three levels of 0.01,0.02 and 0.10 mg/kg in milk were in the range of 65.2%-110%,with relative standard deviations(RSDs)of 3.6%-13%.This method is sensitive,reliable and accurate,and could be applied to the determination of 232 kinds of pesticide residues in dairy products,as well as the multipesticide residues in the routine analysis.