同位素稀释法测定乳制品中的残留氯霉素  

Determination of residual chloramphenicol in milk and dairy products by isotope dilution

作　　者：唐吉旺 周丛 林源 肖泳 钟文涛 吴海智 

机构地区：[1]湖南省产品商品质量监督检验研究院,湖南长沙410007

出　　处：《化学研究》2014年第1期86-89,共4页Chemical Research

摘　　要：建立了同位素稀释高效液相色谱串联质谱测定乳制品中氯霉素残留的方法；往待测样品中加入同位素内标氯霉素-Ds，用乙腈进行提取，取部分提取液加水稀释，并于4℃放置1h后冷冻、离心分离，取上清液进行负离子选择反应监测模式下的液相色谱-质谱技术检测；并确定了优化检测条件．结果表明，在优化的检测条件下，该方法在0．1～10μg／L氯霉素浓度范围内有良好的线性关系，相关系数为0．9998，检出限（S／N=3）为0．1μg／kg．其在不同添加水平（0．02、2、10μg／L）下对液体乳和奶粉两种样品的平均回收率分别为95．0％～102．5％和90．0％～101．0％，相对标准偏差分别为1．86％～5．35％和2．16％～5．64％．该方法操作简便快速、灵敏度高、重现性好、便于大批量的样品分析，符合法规残留限量监测要求，为监测乳制品质量安全提供了-种较好的检测手段．An isotope dilution high-performance liquid chromatography-tandem mass spectrometry （HPLC-MS/MS） method was developed to determine residual chloramphenicol （denoted as CAP） in milk and dairy products. Chloramphenicol-D5 as an isotope internal standard was added in to-be-tested samples which were extracted with acetonitrile. A part of the extracted solution was diluted with water and stored at 4 ℃ for 1 h, followed by freezing and separating via centrifugation. Resultant supernatant was finally analyzed by HPLC-MS/MS in the negative ionization mode and identified in selected reaction monitoring mode; and the optimal monito- ring condition was established. Results indicate that under the optimized monitoring condition, the established method exhibits a good linearity in CAP concentration range of 0.1-10μg/L. The correlation coefficient is 0.999 8, and the limit of detection （S/N = 3） is 0.1 μg/kg. Moreover, the average recoveries of CAP spiked in liquid milk and powdered milk at different addition levels of 0.02, 2.0, 10.0 μg/L are 95.0%--102.5% and 90.0%-101.0%, and the relative standard deviations are 1.86%--5.35% and 2.16%--5.64%, respectively. In one word, the present method is convenient, rapid, sensitive, repeatable and suitable for monitoring a large amount of samples, meeting the regulation requirement of residues limits and providing a good means for monitoring quality security of milk and dairy products.

关 键 词：同位素稀释 高效液相色谱一串联质谱 乳制品 氯霉素 测定 

分 类 号：O657.63[理学—分析化学]