低温液液萃取/超高效液相色谱-串联质谱法快速测定鲜枣中氟虫腈及代谢物

Determination of Fipronil and Its Metabolites in Fresh Jujube by Low Temperature Liquid-Liquid Extraction / Ultra High Liquid Chromatography-Tandem Mass Spectrometry

采用低温液液萃取技术,对鲜枣中的氟虫腈及其代谢物残留进行提取和净化,并利用超高效液相色谱-串联质谱法（UPLC-MS/MS）进行定性和定量分析。鲜枣样品以乙腈作为提取溶剂,-25℃低温液液萃取后,直接进样分析,采用负离子多反应监测（MRM）模式,外标法定量。结果表明,在优化条件下,氟虫腈及其代谢物在0.02～10μg/L范围内线性关系良好,相关系数（r2）大于0.999,检出限为0.005～0.02μg/kg,在不同加标浓度下的平均回收率为78.5%～95.8%,相对标准偏差（RSD）为3.4%～6.9%。该方法快速、简便、灵敏,适用于鲜枣中氟虫腈及其代谢物的快速测定。

An analytical method for the qualitative and quantitative analyses of fipronil and its metabolites residues in fresh jujube was developed by using low temperature liquid-liquid extraction and ultra high liquid chromatography-tandem mass spectrometry（ UPLC-MS / MS）. The fresh jujube sample was extracted with acetonitrile,followed by liquid-liquid extraction at-25 ℃. The analysis of fipronil and its metabolites was performed under negative ion mode and multiple reaction monitoring（ MRM）,quantified by the external standard method. Under the optimized conditions,the fipronil and its metabolites showed good linearities in the range of 0. 02-10 μg / L,with correlation coefficients（ r2） higher than 0. 999. The limits of detection of the method were in the range of 0. 005-0. 02 μg / kg. The average recoveries of fipronil and its metabolites in fresh jujube matrices were in the range of 78. 5%-95. 8% with relative standard deviations of 3. 4%-6. 9%. The method is simple and highly sensitive,and is suitable for the rapid determination of fipronil and its metabolites in fresh jujube.