气相色谱-串联质谱法测定淡水鱼中氯霉素残留量

Determination of chloramphenicol residues in freshwater fish by GC-MS/MS

目的建立气相色谱-串联质谱法(GC-MS/MS)测定淡水鱼中氯霉素残留量的方法。方法称取混匀后的样品,加入内标D5-氯霉素,用乙酸乙酯提取,正己烷脱脂,硅胶固相萃取柱净化,N,O双三甲基硅烷三氟乙酰胺-1%三甲基氯硅烷(BSTFA-1%TMCS)硅烷化衍生,采用GC-MS/MS分析,选择反应监测(SRM)方式测定。结果氯霉素浓度为0.20μg/L^20μg/L,相关系数为0.999 6,相对标准偏差为1.58%~3.30%(n=7),加标回收率为80.0%~107.2%(n=3),方法检出限为0.015μg/kg。结论方法稳定、灵敏度高,选择性好,适用于氯霉素残留量的分析。

Objective To develop a method for determination of chloramphenicol residues in freshwater fish by gas chromatography / tandem mass spectrometry（ GC-MS / MS）. Methods After added with internal reference of D5-chloramphenicol,the homogenized fish samples were extracted with ethyl acetate. Then the extractions were defatted with hexane. Further cleanup of the extractions was performed on a silica solid phase extraction column. The purified chloramphenicol in the extraction were derived with N,O-bis（ trimethylsilyl） trifluoroacet-amide（ BSTFA）-trimethylchlorosilane（1% TMCS）. Chloramphenicol content in the extractions was measured by GC-MS / MS in selected-reaction monitoring（ SRM） mode. Results The correlation coefficient was 0. 999 6 under the chloramphenicol concentration in the range of 0. 20 μg / L-20 μg / L. The relative standard deviation was in the range of 1. 58%-3. 30%（ n = 7）,and the rates of recovery ranged from 80. 0% to 107. 2%（ n = 3）. The detection limit of this method reached to 0. 015 μg / kg. Conclusion This method is stable,sensitive and selective,so that it is suitable for the determination of chloramphenicol residue quantity.