液相色谱-串联质谱法检测畜禽产品中维吉尼亚霉素M1和S1残留

建立了畜禽产品中维吉尼亚霉素M1和S1药物残留检测的液相色谱-串联质谱分析方法。样品以甲醇-乙腈溶液(1:1, v/v)提取,上清液经0.01 mol/L磷酸二氢铵溶液稀释后,Oasis HLB固相萃取小柱净化,Luna C18色谱柱分离,以乙腈和含0.1%(体积分数)甲酸的5 mmol/L乙酸铵水溶液作为流动相进行梯度洗脱,电喷雾正离子模式电离(ESI+),多反应监测(MRM)模式检测,外标法定量。该方法对两物质线性范围均为0.15～10.0 μg/L,相关系数r2均大于0.999;定量下限均为0.25 μg/kg。在不同基质中,0.25、0.50、2.5 μg/kg3个添加水平的平均回收率范围为71.2%～98.4%,精密度范围为3.6%～15.4%。该方法具有快速简便、灵敏度高、准确性强等特点,适用于畜禽产品中维吉尼亚霉素的检测。

Determination of virginiamycin M1 and S1 residues in livestock and poultry products by liquid chromatography-tandem mass spectrometry

A liquid chromatography-tandem mass spectrometry method was established for the determination of virginiamycin M1 and S1 residues in livestock and poultry products. The sample was extracted by methanol-acetonitrile solution (1:1, v/v). The supernatant was diluted with 0.01 mol/L ammonium dihydrogen phosphate solution, then purified and concentrated on an Oasis HLB cartridge. The separation of virginiamycin M1 and S1 was performed on a Luna C18 column with the mobile phases acetonitrile and 5 mmol/L ammonium acetate aqueous solution (containing 0.1% (v/v) formic acid) in a gradient elution mode. The identification and quantification of the drugs were carried out by positive electrospray ionization (ESI + ) in the multiple reaction monitoring (MRM) mode using external standard method. The calibration curves showed good linearity in the range of 0.15-10.0 microg/L with correlation coefficients (r2) above 0. 999. The limits of quantities (LOQs) were both 0.25 microg/kg. The average recoveries of the two drugs spiked at 0.25, 0.5 and 2.5 microg/kg levels in different matrices were between 71.2% and 98.4%, and the relative standard deviations (RSDs) were between 3.6% and 15.4%. The method is simple, rapid, sensitive and accurate. It is suitable for the confirmation and quantification of virginiamycin M1 and S1 residues in livestock and poultry products.