牛奶中氯霉素残留的气相色谱测定法研究

Study on Determination of Chloramphenicol Residue in Milk by GC

研究了牛奶中氯霉素残留的气相色谱法测定方法.用乙酸乙酯提取,蒸干,4%氯化钠溶液溶解残渣,正己烷脱脂后过C18固相萃取柱净化,甲醇洗脱,硅烷化试剂50 ℃衍生30 min后测定.该方法在添加浓度为0.1～1.0 ng/ mL时,氯霉素回收率为71.2%～87.8%,批间变异系数为14.3%～19.7%,检测限为0.04 μg/L ,定量限为0.1 μg/L ,达到了欧盟的规定要求,适合牛奶中氯霉素残留分析.

A gas chromatographic （GC） method was developed for determination of chloramphenicol （CAP） residue in milk. Samples were extracted with ethyl acetate, the extracts were defatted with hexane and subjected to a SPE column activated by methanol and water in succession. Chloramphenicol was eluted with methanol from the SPE column. The eluate was dried by N2 and the residue reacted with BSTFA ＋ TCMS at 50℃ for 30 min. Then, the derivatives were analyzed by GC. The recoveries were 52.4 % - 108.1% when the chloramphenicol concentration were 0.1 - 1.0 ng/mL. The inter-batch RSD were from 14.31% to 19.76%. The detection limit was 0.1 μg,/L. The RSD and detection limit satisfied the requirements of European Union Standard.