超高效液相色谱-串联质谱法测定鸡肉和牛肉中五种常用抗球虫药

建立了鸡肉和牛肉中五种常用抗球虫药物残留检测的超高效液相色谱-串联质谱方法（UPLC—MS／MS）。样品用乙腈提取，吹干后用50％甲醇溶解，正己烷去脂后，供液相色谱-串联质谱法分析。液相色谱条件为：色谱柱为WatersBEHC18柱（50mm×2．1mm，1．7μm）；流动相为乙腈-20mmol／L乙酸铵水溶液，梯度洗脱；柱温30℃；流速0．3mL／min；进样量10μL。质谱条件为：电喷雾离子源（ESI’），多反应监测（MRM）方式采集。结果表明：在10～500μg／L的系列浓度范围内，五种抗球虫药物的相关系数R2〉0．990；方法检测限为5μg／kg，定量限为10μg/kg；从100、200、500μg／kg三个添加浓度检测结果可以看出，方法的平均回收率为75．4％～109％，批内、批间RSD均〈15％。本方法简便快捷、定性准确，可以满足兽药残留分析的求。

Determination of five Coccidiostats in Chicken and Beef by UPLC-MS/MS

A UPLC - MS/MS method was established for the determination of five coccidiostats in chicken and beef tissues. The samples were extracted by acetonitril, dissolved by 50% methanol after evaporation, degreasing by hexane and determined on UPLC - MS/MS. UPLC condition： the chromatography column was Waters BEH C18 column of 50 mm × 2. 1 mm, 1.7μm; mobile phase was acetonitril and water（containing 20 mmoL/L ammonium acetate） ;column temperature was 30 ℃ ;flow rate was 0.3 mL/min;injection volume was 10 μL. Mass spectrometry condition： ESI＋ and MRM mode. The calibration curves were good linear between the peak areas and concentrations from 10 -500 μg/L,the correlation coefficient R2 〉0. 990. The detection limit of the method was 5 p,g/kg, and the limit of quantification was 10 μg/kg. The average recoveries from spiked chicken and beef at the three concentrations of 100,200 and 500μg/kg ranged from 75.4% - 109% （ n = 6） , and intra - and inter - batch variation coefficients were less than 15%. The method was simple and rapid, and it was satisfied to detect veterinary drug residues in animal derived food.