提出了固相萃取一步式净化-超高效液相色谱-串联质谱法(UHPLC-MS/MS)同时测定畜禽肉中磺胺类、喹诺酮类、大环内酯类和苯并咪唑类等46种兽药残留量的方法。样品通过乙腈振荡提取后,由正己烷重复脱脂,采用SHIMSEN Qvet-NM固相萃取柱一步式净化。净化后的样品经ZORBAX Eclipse Plus C₁₈色谱柱分离,以不同体积比的0.1%(体积分数)甲酸溶液-乙腈混合液为流动相进行梯度洗脱,串联质谱多反应监测模式分析,内标法定量。结果表明:46种兽药的质量浓度在一定范围内与目标物、内标峰面积的比值呈线性关系,磺胺类与喹诺酮类的检出限(3S/N)为0.1 μg·kg^-1,大环内酯类和苯并咪唑类的检出限(3S/N)为0.5 μg·kg^-1,远低于欧盟规定的肉制品中兽药残留限量(禁用的兽药除外)。按照标准加入法进行回收试验,回收率为72.9%~110%,测定值的相对标准偏差(n=6)均小于15%。

A method for simultaneous determination of residues of 46 veterinary drugs in livestock and poultry meat, including sulfonamides, quinolones, macrolides and benzimidazoles, was proposed by ultra-high performance liquid chromatography-tandem mass spectrometry with one-step purification of solid phase extraction. The sample was extracted with acetonitrile by oscillation, and then repeatedly degreased by n-hexane. The obtained solution was purified by one-step purification with SHIMSEN Qvet-NM solid phase extraction column. The purified sample was separated by ZORBAX Eclipse Plus C₁₈ column, using the mixture of 0.1%(volume fraction) formic acid solution and acetonitrile at different volume ratios as the mobile phase for gradient elution. Multiple reaction monitoring mode of tandem mass spectrometry was adopted, with internal standard method for quantitative analysis. As shown by the results, linear relationships between values of mass concentration and peak area ratio of target to internal standard were found in definite ranges, with detection limits (3S/N) of 0.1 μg·kg^-1 for sulfonamides and quinolones and detection limits (3S/N) of 0.5 μg·kg^-1 for macrolides and benzimidazoles. The detection limits were far lower than the limits of veterinary drug residues in meat products set by the European Union (except for prohibited veterinary drugs). Test for recovery was made by standard addition method, giving results in the range of 72.9%-110%, with RSDs (n=6) of the determined values less than 15%.