微波消解ICP-MS测定粮食、蔬菜中8种元素

目的建立电感耦合等离子体质谱(ICP-MS)测定粮食、蔬菜中8种元素的方法。方法样品在硝酸介质中经微波消解,消解液用ICP-MS同时测定粮食、蔬菜中Al、As、Cd、Cu、Pb、Zn、Fe和Ca等8种元素的含量。结果用ICP-MS法测定了国家标准参考物质贻贝(GBW08571)和小麦粉(GBW08503B),其测定值在标准参考值范围内,方法的准确度在79.4%~111.5%,相对标准偏差为1.1%~6.6%。样品加标回收率为93.5%~110%。分析中采用了内标校正和稀释样品的方法,有效地校正了基体干扰。结论微波消解ICP-MS方法简便、快速、准确、可靠,适于食品中多元素同时测定。

Determination of eight elements in grain and vegetable by microwave digestion-ICP-MS

Objective To set up a method for simultaneous determination of eight elements in grain and vegetable by microwave digestion-inductively coupled plasma-mass spectrometry(ICP-MS).Methods Food samples were digested in a microwave digestion system with nitric acid solution, and contents of Al, As, Cd, Cu, Pb, Zn, Fe and Ca in the digestion solutions were determined simultaneously by ICP-MS.Results The national standard reference materials such as mussel(GBW08571)and wheat powder(GBW08503B)were applied in the process of sample analysis, and the determination values of the standard reference materials were within the certified values. The accuracy of the method was 79.4%-111.5%, and the RSD was less 1.1%-6.6%. The recoveries of the spiked samples were 93.5%-110%. In order to reduce the matrix interference, the calibration of internal standard and the sample dilution were introduced for ICP-MS.Conclusion This method has simple operation, rapid analysis, high accuracy, and reliable, and can be applied in simultaneous determination of multiple elements in food samples.