分散固相萃取-液相色谱-串联质谱法测定常见动物源性食品中42种兽药残留

采用分散固相萃取结合液相色谱-串联质谱，选择4种代表性动物源性食品作为基质，建立了13类42种兽药残留的分析方法。样品经水分散后，以5%（v/v）甲酸乙腈提取，提取液经盐析后取乙腈层，用分散固相萃取净化包净化。目标物用C₁₈色谱柱（100 mm×2.1 mm，2 μ m）分离，以甲醇和0.1%（v/v）甲酸水溶液为流动相进行梯度洗脱，利用电喷雾离子源多反应监测模式进行检测。42种兽药在各自的浓度范围内线性关系良好，相关系数均大于0.995；大多数化合物在4种样品基质中的3个添加水平下的平均回收率为65.8%~135.5%，相对标准偏差为0.5%~14.2%（n=6）；检出限（LOD，S/N=3）和定量限（LOD，S/N=10）分别为0.01~1.68 μ g/kg和0.01~5.62 μ g/kg。该方法简便、快速、灵敏，适用于动物源性食品中42种兽药残留的定量、定性分析。

Determination of 42 veterinary drug residues in common animal derived food by dispersive solid phase extraction coupled with liquid chromatography-tandem mass spectrometry

A liquid chromatography-tandem mass spectrometry method, coupled with a dispersive solid phase extraction (DSPE) procedure for sample preparation, was developed to determine 13 classes of 42 veterinary drugs in four representative animal-derived foods. The analytes were dispersed with water, extracted with acetonitrile containing 5% (v/v) formic acid, salted out by salts, and purified by DSPE. The analytes were separated on a C18 column (100 mm×2.1 mm, 2 μ m) with gradient elution using the mobile phase containing methanol and 0.1% (v/v) formic acid aqueous solution. Electrospray ionization-mass spectrometry was performed in multiple reaction monitoring mode for analysis of the 42 compounds. The correlation coefficients of the standard calibration curves for the 42 veterinary drugs were all above 0.995. Most recoveries at three spiked levels in the four representative matrixes ranged from 65.8% to 135.5%, with relative standard deviations of 0.5%-14.2% (n=6). The limits of detection (LODs, S/N=3) and the limits of quantification (LOQs, S/N=10) were 0.01-1.68 μ g/kg and 0.01-5.62 μ g/kg, respectively. The method is simple, rapid, sensitive, and suitable for the simultaneous determination of the 42 veterinary drugs in animal-derived food.