微波消解-ICP-MS法测定奶粉中总碘和钾、钙、钠元素  

Determination of Total Iodine, Potassium, Calcium and Sodium in Milk Powdered by ICP-MS with Microwave Digestion

作　　者：丁玉龙[1] 周峰 宋瑞[1] 于学雷 王莹[1] 葛淑丽[1] DING Yulong;ZHOU Feng;SONG Rui;YU Xuelei;WANG Ying;GE Shuli(Shanghai Quality Supervision and Inspection Technology Research Institute,Shanghai 200233;Perkin Elmer(Shanghai)Co.,Ltd.,Shanghai 200233)

机构地区：[1]上海市质量监督检验技术研究院,上海200233 [2]美国铂金艾尔默公司(上海),上海200233

出　　处：《食品工业》2021年第3期309-313,共5页The Food Industry

基　　金：上海市市场监管局课题(2018-43)。

摘　　要：为建立婴幼儿配方奶粉中总碘、钾、钙、钠元素含量的微波消解-电感耦合等离子体质谱测试方法,以硝酸为消解介质,铑和钪作内标,优化仪器检测的条件,消除干扰,并进行方法检出限、精密度和方法准确性等试验。结果显示,碘、钾、钙、钠元素检出限分别为5.94μg/kg, 2.47 mg/kg, 3.64 mg/kg和2.78 mg/kg。线性范围:碘, 0~25μg/L;钾、钙、钠, 0~100 mg/L。相关系数r优于0.999。相对标准偏差δRSD均在5.0%以下,加标回收率在95.1%~108%之间,奶粉标准物质的测定结果与标实值一致。结果表明,所建立的方法灵敏度高、简便、快速、准确,适用于奶粉样品中总碘、钾、钙、钠含量的测定。A method for the determination of total iodine, potassium, calcium and sodium by microwave digested-inductively coupled plasma mass spectrometry(ICP-MS) in milk powdered using nitric acid as the digestion medium and Rh, Sc as the internal standard was developed. The experimental condition was optimized, and the interference was eliminated. Some experiments including detection limit, precision and accuracy were performed. The results showed that the detection limit of I, K, Ca and Na was 5.94 μg/kg, 2.47 mg/kg, 3.64 mg/kg and 2.78 mg/kg, while the linear range of I was 0-25 μg/L, the linear ranges of K, Ca, and Na were 0-100 mg/L, and the linear coefficient(r) was better than 0.999. The precision of the method (δRSD) was less than 5.0%. The determined iodine contents were in good agreement with the certified values. The recoveries of real samples were from 95.1% to 108%. The experiments showed that this method is sensitive, simple and rapid, and it was accurate for the determination of iodine, potassium, calcium and sodium contents in infant formula.

关 键 词：婴幼儿配方奶粉 碘 微波消解 电感耦合等离子体质谱法 

分 类 号：TS252.51[轻工技术与工程—农产品加工及贮藏工程] O657.63[轻工技术与工程—食品科学与工程]