高效液相色谱-高分辨质谱法测定奶粉及保健品食品中的左旋肉碱  

Determination of L-carnitine in milk powder and healthy food by high performance liquid chromatography coupled with high resolution mass spectrometry

作　　者：王艳 刘芸 姜珊 丁涛 林宏 王栩璐 陆曦 邓晓军 伊雄海 黄艳玲 WANG Yan;LIU Yun;JIANG Shan;DING Tao;LIN Hong;WANG Xu-Lu;LU Xi;DENG Xiao-Jun;YI Xiong-Hai;HUANG Yan-Ling(Jiangsu Zhongce Testing Service Co.,Ltd,Nanjing 210001,China;Nanjing Customs Animal,Plant and Food Inspection Center,Nanjing 210001,China;Shanghai Customs Animal,Plant and Food Inspection and Quarantine Technology Center,Shanghai 200135,China;Soutueast University Chengxian College,Nanjing 210088,China)

机构地区：[1]江苏中测检测服务有限公司,南京210001 [2]南京海关动植物与食品检测中心,南京210001 [3]上海海关动植物与食品检验检疫技术中心,上海200135 [4]东南大学成贤学院,南京210088

出　　处：《食品安全质量检测学报》2020年第17期5920-5926,共7页Journal of Food Safety and Quality

基　　金：长三角区域进口食品、农产品及化妆品智慧监管关键技术研究及示范应用项目(19395810100)。

摘　　要：目的建立高效液相色谱-高分辨质谱法测定奶粉及保健食品中左旋肉碱的含量。方法奶粉及保健食品样品经适量40℃水溶解后,加乙酸锌沉淀蛋白,待样品冷却至室温后用水定容至50mL,并超声提取30 min。在4℃条件下,待测溶液经8000 r/min的速度离心3 min,取上清液过0.45μm水相滤膜。经质谱正离子模式测定,同位素内标法定量。结果左旋肉碱0.1~4.0μg/mL范围内呈良好线性关系,相关系数为1.0000,方法检出限为0.1μg/kg,定量限为0.2μg/kg。加标回收率为98%~110%,相对标准偏差为0.2%~0.5%。对奶粉质控样品进行测定,结果与证书结果一致。结论该法前处理简单、测定快速、准确度高,灵敏度好,适用于奶粉及保健食品中左旋肉碱的快速分析检测。Objective To establish a method for determination of L-carnitine in milk powder and healthy food by high performance liquid chromatography coupled with high resolution mass spectrometry.Methods The milk powder samples and healthy food samples were dissolved by appropriate amount of water at 40℃,precipitated with zinc acetate,and diluted to 50 mL when the samples were cooled to the room temperature,and conducted for 30 min by ultrasonic extraction.The solution was centrifuged at 8000 r/min for 3 min at 4℃,and the supernatant was filtered through a 0.45μm aqueous phase membrane,measured by mass spectrometry in positive ion mode,and quantified by isotope internal standard method.Results L-carnitine showed a good linear relationship in the range of 0.1–4.0μg/mL,the correlation coefficient was 1.0000,the limit of detection the method was 0.1μg/kg,and the limit of quantification was 0.2μg/kg.The standard recoveries were 98%–110%,and the relative standard deviations were 0.2%–0.5%.The quality control sample of milk powder was determined and the result was consistent with the certificate.Concusion The method has simple pretreatment,rapid determination,high accuracy and good sensitivity,and it is suitable for the rapid analysis and detection of L-carnitine in milk powder and health food.

关 键 词：高效液相色谱-高分辨质谱法 左旋肉碱 同位素内标法 奶粉及保健食品 

分 类 号：O657.63[理学—分析化学] TS252.51[理学—化学] TS218[轻工技术与工程—农产品加工及贮藏工程]