LC-MS/MS测定牛奶中氟虫腈及代谢物残留量

建立了液相色谱-串联质谱(L C-MS/MS)法测定牛奶中氟虫腈及其代谢物残留量的方法.根据基质及目标物特点选择乙腈进行提取,通过比较Cleanert PEP Plus固相萃取柱,Florisil固相萃取柱、Waters Oasis PRiME HLB净化柱,氨基石墨复合柱净化效果及实验效率,选择Cleanert PE...

Determination of Fipronil and Its Metabolites Residues in Milk by Liquid Chromatography-Tandem Mass Spectrometry

A liquid chromatography-tandem mass spectrometry(LC-MS/MS)was established for the determination of fipronil and its metabolites in milk.The samples were extracted with acetonitrile,extract liquor was cleaned up by Cleanert PEP Plus(60 mg/3 mL),comparing with Florisil-solid phase extraction column,Waters Oasis PRiME HLB-solid phase extraction column and GCB-NH2-solid phase extraction column.The separation was performed on an Agilent Eclipse plus-C18 column with the flow phases of 10 mmol/L ammonium acetate aqueous solution containing 0.1%formic acid and acetonitrile containing 0.1%formic acid.The identification and quantitation of fipronil and its metabolites were performed by MS/MS in negative electrospray ionization(ESI-)and multiple reaction monitoring(MRM)mode.The quantitative analysis was carried out by external standard method.A good linear relationship,with the correlation coefficient(R²)greater than 0.99,was found in the mass concentration range of 1~50μg/kg.The limit of detection and limit of quantitation were 0.6μg/kg and 1μg/kg respectively.The recoveries of fipronil and its metabolites in blank milk matrixes spiked with three levels from 82.5%to 97.4%,and the relative standard deviations were between 4.0%and 10.5%.The method is simple,rapid,sensitive,accurate and suitable for the determining of fipronil and its metabolites.