气质联用法测定叶菜类蔬菜中的氟虫腈及其代谢物残留量

Determination of Fipronil and Its Metabolites Pesticide Residues in Leaf Vegetables by GC-MS

[目的]建立叶菜类蔬菜中氟虫腈及其代谢物残留量的气相色谱-质谱联用法。[方法]样品经乙腈萃取,N-丙基乙二胺键合硅胶固相萃取柱净化,采用气相色谱-质谱仪进行确认和定量。[结果]氟虫腈及其代谢物在0.005~0.500μg/mL范围内呈良好线性关系(R^2>0.999),方法检出限为0.5μg/kg,定量限为2μg/kg;氟虫腈及其代谢物的回收率为81.06%~107.1%,精密度为4.66%~18.90%。通过对100批次5种常见市售叶菜类蔬菜的筛查,阳性主要为小白菜。[结论]该方法灵敏度高,定性及定量准确,适用于叶菜类蔬菜中氟虫腈及其代谢物残留量的测定。

[Objective]The study established determination method of fipronil and its metabolite residues in leafy vegetables by GC-MS.[Method]The sample was extracted by acetonitrile,purified with N-propyl ethylenediamine bonded silica SPE column(PSA),confirmed and quantified by GC-MS.[Result]The fipronil and its metabolite showed good linear relationship(R^2>0.999)in the concentration range of 0.005-0.500μg/mL.The method detection limit(MDL)was 0.5μg/kg,the limit of quantification(LOQ)was 2μg/kg;the recovery rate of fipronil and its metabolites were 81.06%-107.1%,the precision were 4.66%-18.90%.Through the detection of 100 batches leafy vegetables,the positive samples were Pakchoi.[Conclusion]The method has the advantages of high sentisivity,quantitative and qualitative accuracy,and it is suitable for the detection of fipronil and its metabolite residues in leafy vegetables.