快速测定婴幼儿乳粉中的氯霉素残留

Rapid Determination of Residual Chloramphenicol in Infant Milk Powder by LC-MS-MS

建立一种高效液相色谱-串联质谱法快速测定婴幼儿乳粉中氯霉素残留的方法。样品以D5-氯霉素为内标,碱化后,经乙酸乙酯提取、低温离心、氮吹浓缩,流动相复溶,采用高效液相色谱-串联质谱法测定。结果表明:在0.1～5μg/L范围内氯霉素呈良好的线性关系,高、中、低浓度回收率为80%～110%,精密度小于15%,定量限为0.1μg/kg。本方法快速、简便,适于乳粉中氯霉素残留的快速测定。

A high performance liquid chromatography tandem mass spectrometric （HPLC-MS-MS） method was developed for rapid determination of chloramphenicol residue in infant milk powder. DS-Chloramphenicol was used as internal standard. Samples were alkalified, extracted with ethyl acetate and centrifuged at a low temperature. Afterwards, the supernatant was concentrated by nitrogen gas blowing and dissolved again in HPLC mobile phase before HPLC-MS- MS analysis. An excellent linear relationship between peak area and chloramphenicol concentration was obtained over the concentration range of 0.1 to 5 μg/L. Average recoveries of chloramphenicol in a blank matrix across three spike levels ranged from 80% to 110%, and inter-batch and intra-batch precision （RSD） was less than 15%. The limit of quantification of this method was 0.1 μg/kg. This method was rapid, simple and suitable for rapid determination of chloramphenicol residue in infant milk powder.