内标高效液相色谱-质谱/质谱法同时测定蜂蜜中甲硝唑和氯霉素残留量

Simultaneous Determination of Metronidazole and Chloramphenicol Residues in Honey by Internal StandardHigh Performance Liquid Chromatography-Mass Spectrometry/Mass Spectrometry

建立了高效液相色谱-质谱/质谱法同时检测蜂蜜中甲硝唑和氯霉素残留量的方法。样品加入混合内标后,加入水溶解,用乙酸乙酯作为提取液,固相萃取柱净化进行对比,使用C_(18)色谱柱(100 mm×2.1 mm,2.6μm)分离。甲硝唑采用正离子扫描模式,氯霉素采用负离子模式,应用多反应监测模式,内标法定量。结果显示,氯霉素浓度在0.5~20.0 ng·mL^(-1),甲硝唑浓度在1~100 ng·mL^(-1)时,线性关系均良好,相关系数r均大于0.99。方法一处理下,氯霉素的平均回收率在93.5%~111.0%,甲硝唑的平均回收率在97.0%~100.0%,RSD均小于10%。氯霉素和甲硝唑的检出限均为0.10μg·kg^(-1),定量限分别为0.36μg·kg^(-1)、0.50μg·kg^(-1)。通过内标法定量,达到消除基质效应的效果,能满足蜂蜜中甲硝唑和氯霉素残留量的监测要求。

A method was established for simultaneous determination of metronidazole and chloramphenicol residues in honey by high performance liquid chromatography-mass spectrometry/mass spectrometry.After adding mixed internal standard,the samples were dissolved in water,extracted with ethyl acetate,purified by solid phase extraction column for comparison,and separated by C_(18) chromatographic column(100 mm×2.1 mm,2.6 μm).Metronidazole was determined in positive ion scanning mode and chloramphenicol was determined in negative ion mode by multi-reaction monitoring mode and quantitative by internal standard method.The results showed that the concentration range of chloramphenicol was 0.5 ~ 20.0 ng·mL~(-1),and the concentration range of metronidazole was 1 ~ 100 ng·mL~(-1),and the linear relationship was good,and the correlation coefficient r was more than 0.99.Under method one processing,the average recoveries of chloramphenicol and metronidazole were 93.5% ~ 111.0% and 97.0% ~ 100.0% respectively,with RSD less than 10% with the two pre-treatment modes.For chloramphenicol and metronidazole,the limits of detection were 0.10 μg·kg~(-1),and the limits of quantitative were 0.36 μg·kg~(-1) and 0.50 μg·kg~(-1),respectively.Through internal standard method,the matrix effect could be eliminated,and the monitoring requirements for metronidazole and chloramphenicol residues in honey can be met.