液相色谱串联质谱法测定牛组织中氨丙啉残留量

Determination of Amprolium Residues in Bovine Tissues by Liquid Chromatography with Tandem Mass Spectrometry

建立了牛组织中氨丙啉残留量的液相色谱串联质谱测定方法。样品经磷酸盐缓冲液提取后用HLB小柱净化,甲醇洗脱,洗脱液氮吹后用0.1%甲酸-甲醇（90∶10,V/V）溶解,进行LC-MS/MS分析。采用XBridgeTMC18色谱柱分离,用0.1%甲酸-甲醇（90∶10,V/V）作为流动相等度洗脱,电喷雾正离子（ESI＋）模式电离,多反应监测（MRM）模式检测,外标法定量。氨丙啉浓度在5~2000 mg/L范围内具有良好的线性关系,线性相关系数大于0.999;方法检出限为3.50 mg/kg;定量限为11.7 mg/kg。3种组织（牛肉、牛肝和牛肾）添加浓度为25,250,500和750 mg/kg时,平均回收率在81.6%~92.8%之间,批内和批间相对标准偏差均小于15%。

A method was developed for determining residual amprolium in bovine tissues by liquid chromatography with tandem mass spectrometry.The samples were extracted with phosphate buffer solution.Then the extract was directly purified through HLB cartridge after centrifugation.The elution was dried under nitrogen and residues were dissolved in 0.1% formic acid solution/ methanol（9∶1,V/V）.The samples were analyzed by LC-MS/MS on a XBridge TM C18 column with a mixture of 0.1% formic acid solution and methanol（90∶ 10,V/V） as the mobile phase.The samples were quantified with the external standard calibration curve method.Good linearity was obtained for amprolium at the concentration of 5-2000 mg/L with the linear relative coefficient more than 0.999.The recoveries in three kinds of bovine tissues were 81.6%-92.8% at the fortified levels of 25-750 mg/kg with the limit of detection of 3.50 mg/kg and the limit of quantitation of 11.7 mg/kg.The relative standard deviations were less than 15.0%.