虾仁中氯霉素的同位素稀释技术GC/ITMS-MS测定方法的建立

Analysis of chloramphenicol in shrimps by gas chromatography tandem mass spectrometry

目的用氯霉素氘代同位素作为内标,建立虾仁中氯霉素的GC/ITMS-MS检测方法.方法样品中加入同位素内标,用乙酸乙酯提取,正己烷脱脂肪,经SPE C18柱净化,Sylon BFT(BSTFA-TMCS)衍生后进样,采用GC/MS-MS,多级反应离子监测(MRM)检测.结果方法的线性范围为10～500pg,r=0.9958,测定限为0.3ng/g;0.3,0.5和1.0ng/g加标水平的平均回收率分别为104%,111%和95%,相对标准偏差小于20%.结论该方法灵敏度高,准确,可靠,满足虾仁中氯霉素的痕量检测需要.

Objective A sensitive method based on isotope dilution gas chromatography tandem mass spectrometry is described for the determination of the antibiotic chloramphenicol （Cap） in shrimp tissue. Methods Homogenized shrimp samples spiked with an isotopically labeled internal standard （d5-Cap） were extracted with ethyl acetate extraction, defatted with hexane, followed by a clean-up step on a SPE C18 cartridge, and then the elute was evaporated and derivatized with Sylon BFT { N, O-bis （trimethylsily） trifluoroacetamide [ BSTFA]-trimethylchlorosilane [ TMCS 1 , 99 ＋ 1 } Analyzes were determined by GC/MS-MS in MRM mode. Results Internal calibration curves obtained for Cap/ds-Cap in the 5 to 500 pg range were linear with correlation coefficients of 0.9958. Limit of quantitation （LOQ） was 0.3ng/g. Shrimp tissues were fortified with Cap at 0.3, 0.5, 1.0ng/g level, average recoveries were 104% , 111% and 95 % , respectively. Conclusion The proposed method allows the detection, quantitation and confirmation of Cap in shrimps with high accuracy and sensitivity.