内标液相色谱-串联质谱法测定蜂蜜中氯霉素、甲砜霉素和氟苯尼考残留

目的建立液相色谱-串联质谱法测定蜂蜜中氯霉素、甲砜霉素和氟苯尼考的分析方法。方法以氯霉素-D5为内标,样品用乙酸乙酯提取,提取液在45℃氮气吹至近干,残渣用2mL水溶解,溶解液过Oasis HLB柱净化,洗脱液在45℃氮气吹干, 50%甲醇水溶液定容,后经正己烷脱色脱脂、PSA粉末吸附净化,高速离心过膜后用串联四极杆检测。样液经过Agilent Eclipse XDB-C₁₈色谱柱分离,甲醇-水流动相梯度洗脱,多反应监测扫描模式检测。采用内标法定量。结果氯霉素在0.1~4.0μg/kg、甲砜霉素和氟苯尼考在0~40.0μg/kg呈良好的线性关系,相关系数大于0.999,回收率为93.7%~109.7%,RSD为0.7%~11.4%,检出限为0.03~0.09μg/kg,定量限为0.1~0.3μg/kg。结论该方法准确、检出限低、重现性好,适用于蜂蜜中氯霉素、甲砜霉素和氟苯尼考残留的检测。

Determination of chloramphenicol, sulfoxycin and fluorphenicol residues in honey by liquid chromatography-tandem mass spectrometry with interior label

Objective To establish a method for determination of chloramphenicol,sulfoxycin and fluorophenicol in honey by liquid chromatography-tandem mass spectrometry(LC-MS/MS).Methods Chloramphenicol-D5 was used as the internal standard.The honey sample was extracted with ethyl acetate,the extract was blown to near dry at 45℃with nitrogen,and the residue was dissolved with 2 mL water.The solution was purified by OASIS HLB column,the eluent was dried at 45℃with nitrogen,and the volume was fixed with 50%methanol solution.The eluent was decolorized and degreased with N-hexane,and purified with PSA powder adsorption.The sample was separated by Agilent Eclipse XDB-C18 chromatographic column,and eluted by methanol-water mobile phase gradient.The eluent was detected by MRM scanning mode of ESI ion source.Chloramphenicol was quantified by internal standard method.Results Chloramphenicol showed a good linear relationship between 0.1?4.0 g/kg,as well assulfoxycin and flufenicol ranged from 1.0 g/kg to 40.0 g/kg.The correlation coefficient was greater than 0.999,recoveries were 93.7%?109.7%,RSDs were 0.7%?11.4%,the limits of detection were 0.03?0.09μg/kg,and the limits of quantitative were 0.1?0.3μg/kg.Conclusion This method is accurate,has low limit of detection and good reproducibility,and is suitable for the determination of chloramphenicol,sulfoxamicol and florfenicol residues in honey.