液相色谱-串联质谱法测定果蔬中的氟虫腈及其代谢物

Determination of Fipronil and Its Methabolites in Fruits and Vegetables by Liquid Chromatography-tandem Mass Spectrometry

建立液相色谱-串联质谱(LC-MS/MS)测定7种果蔬(番茄、黄瓜、韭菜、马铃薯、西瓜、苹果和橙子)中氟虫腈及其代谢物的分析方法。样品经组织捣碎、乙腈提取,经氨基柱和二氯甲烷+甲醇(95︰5)净化洗脱处理,2 mL甲醇定容,采用Phenomenex H18色谱柱分离。结果表明,氟虫腈及其代谢产物添加浓度为0.01 mg/kg和0.02 mg/kg,平均回收率为80.67%~117.67%,相对标准偏差(δ_(RSD),n=6)为0.30%~8.78%;试验方法检出限为0.01 mg/kg,相关系数均大于0.9995。试验方法操作简便快捷,安全性高,通过一种检测方法可同时测定果蔬中氟虫腈及其代谢物残留量,准确度和灵敏度高,定量下限低于或等于国家农药残留限量标准。

A method for the fipronil and its metabolites detection of 7 fruits and vegetables(tomato,cucumber,leek,potato,watermelon,apple and orange)by liquid chromatography-tandem mass spectrometry was established.The samples were mashed,and then extracted with acetonitrile.The extraction was purified by the amino column and dichloromethane+methanol(95︰5).After constant volume with 2 mL methanol,the target analytes were separated on a Phenomenex H18 column.The results showed that the method recovery rates of fipronil and its metabolites were both 80.67%-117.67%,and the precisionδ_(RSD)was 0.30%-8.43%at the levels of 0.01 mg/kg and 0.02 mg/kg.The detection limit of the experimental method was 0.01 mg/kg,and the correlation coefficient was greater than 0.9995.The method is simple,fast,and safe.It could be used to simultaneously determine the residues of fipronil and its metabolites in fruits and vegetables with only one detection method.The accuracy and sensitivity were high,and the lower limit of quantification was less than or equal to national pesticide residue limit standards.