液相色谱-串联质谱-同位素稀释法同时测定猪肉中54种药物残留

建立了应用固相萃取技术和液相色谱-串联质谱法（HPLC-MS/MS）对猪肉中磺胺类、硝基咪唑类、喹诺酮类、大环内酯类、林可酰胺类和吡喹酮共54种药物残留同时测定的方法。样品经乙腈提取，C₁₈固相萃取柱净化，液相色谱-串联质谱法检测（正离子方式，多反应监测模式），同位素内标稀释法进行定量。方法的定量限：磺胺类和硝基咪唑类药物为1.0 μg/kg，喹诺酮类和林可酰胺类药物为2.0 μg/kg，大环内酯类药物为3.0 μg/kg，吡喹酮为0.3 μg/kg；线性良好，相关系数大于0.991；总体回收率为20.9%~121%；相对标准偏差为2.0%~19.8%。

Simultaneous Determination of 54 Drugs Residues in Pork by High Performance Liquid Chromatography-Tandem Mass Spectrometry and Isotopes Dilution Technique

A simultaneous method for the determination of 54 drugs residues(sulfonamides,nitroimidazoles,quinolones,macrolide antibiotics,lincosamides and praziquantel) in pork was developed and validated by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) following solid phase extraction(SPE).The extracts were dissolved and distilled with acetonitrile.After that the supernatant solution was extracted with n-hexane to remove the fat,and then cleaned up with SPE C18 cartridges.The quantitative detection was performed on LC-MS/MS by multiple reaction monitoring(MRM) mode under positive electrospray ionization(ESI+).The one precursor/two product ion transitions were used for each compound.Isotopes dilution internal standard method was used to determine the residue contents in pork.The limits of quantification(LOQs) are 1.0 μg/kg(sulfonamides and nitroimidazoles),2.0 μg/kg(quinolones and lincosamides),3.0 μg/kg(macrolide antibiotics) and 0.3 μg/kg(praziquantel),respectively.Validation parameters are determined as follow correlation coefficients,which are more than 0.991,and the recovery for each analyte ranges of 20.9%—121% with relative standard deviations(RSDs) between 2.0% and 19.8%.