液相色谱-串联质谱法测定猪肉中23种磺胺及其增效剂残留

Liquid chromatography combined with tandem-mass spectrometry for multiresidue determination of sulfonamides and the potentiator in meat

目的:建立猪肉中磺胺及其增效剂多残留检测的液相色谱-串联质谱法(LC-MS/MS),包括磺胺二甲异嘧啶、磺胺吡啶、磺胺甲基嘧啶、磺胺甲基异噁唑、磺胺二甲异噁唑、磺胺嘧啶、磺胺甲噻二唑、磺胺氯哒嗪、磺胺甲氧哒嗪、磺胺间二甲氧嘧啶、磺胺-6-甲氧嘧啶、磺胺噻唑、磺胺邻二甲氧嘧啶、磺胺喹噁啉、磺胺、磺胺脒、磺胺噁唑、磺胺甲氧嘧啶、磺胺二甲嘧啶、磺胺醋酰、磺胺苯吡唑、磺胺硝苯、磺胺苯酰和甲氧苄氨嘧啶。方法:猪肉样品中加入乙腈沉淀蛋白,经正己烷脱脂后,采用液相色谱-三重四极杆串联质谱检测,使用电喷雾离子化源(ESI),在正离子条件下以多反应监测(MRM)方式进行扫描。采用13C6-磺胺甲噁唑为内标定量分析。结果:该法线性范围为1.0～100μg·kg-1(磺胺和磺胺硝苯均从5.0μg·kg-1起),以加标样品计算,在各浓度水平下,除磺胺外,各被测物的方法回收率均为80%～120%,各被测物的最低定量浓度为0.2～5.0μg·kg-1。结论:该法灵敏、快速、准确,可用于猪肉中磺胺类物质及其增效剂的多残留检测。

Objective：A specific and sensitive liquid chromatography tandem mass spectrometry（LC-MS/MS）method was developed for the multiresidue determination of sulfisomidine, sulfapyridine, sulfamerazine, sulfamethoxazole, sulfisoxazole, sulfadiazine, sulfamethizole, sulfachlorpyridazine, sulfamethoxypyridazine, sulfadimethoxine, sulfamonomethoxine, sulfathiazole, sulfadoxine, sulfaquinoxaline, sulfanilamide, sulfaguanidine, sulfamoxole, sulfameter,sulfadimidine,sulfacetamide, sulfaphenazole, sulfanitran, sulfabenzamide and a potentiator, trimethoprim,in meat.Method：Samples were prepared by protein precipitation with acetonitrile and defatting with n-hexane.The analytes were detected with API 4000 triple quadrupole tandem mass spectrometer equipped with ESI source in the positive ion mode.Quantitation was performed using multiple reaction monitoring（MRM）of the transitions with 13C6-sulfamethoxazole as the internal standard.Results：The linear regressions were fitted over the concentration ranges of 1.0-100 μg · kg-1 in meat for the analytes（except sulfanilamide and sulfanitran, which ranged from 5.0 μg·kg-1）.The method recovery of the analytes（except sulfanilamid）evaluated by determining the spiked samples at all levels were within 80%-120%, respectively.The lower limits of quantification（LOQ）were from 0.2 to 5.0 μg·kg-1.Conclusion： The LC-MS/MS method is sensitive, rapid and accurate enough to determine both sulfonamides and the potentiator residues in meat, simultaneously.