开放式微波消化-ICP-MS法快速测定食品中多种微量元素

Determination of Multi-Elements in Food by ICP-MS with Open Vessel Microwave Digestion

开放式微波消解系统消化食品样品 ,以 45Sc、89Y、1 1 5In、2 0 9Bi作内标元素抑制分析信号的动态漂移 ,加入 1 %异丙醇消除 C元素对 As、Se等元素的干扰 ,建立食品中多种元素同时测定的ICP- MS方法。对 4类食品 (奶粉、鹅肝酱、水果片、燕麦片 )中的 1 2种元素 (Al、Cr、Ni、Ge、As、Se、Ag、Cd、Sn、Sb、Pb、Hg)进行了直接测定 ,绝大部分回收率在 85 %— 1 1 0 %之间 ;线性相关系数均大于 0 .999;精密度 (RSD)值 <1 0 %。对国家标准物质 (SRM)进行了分析 ,测得值与标准参考值相吻合。该法灵敏度、精密度和准确度都能满足有关标准的要求 ,具有多元素同时分析、样品前处理简单、干扰少、测定快速准确 ,省事省力等优点。

The samples were digested by open vessel microwave sample preparation system.Four internal standard elements of 45Sc- 89Y- 115In- 209Bi were selected to compensate the drift of analytical signals.1% Isopropanol were added to samples to overcome the interferences from residual carbon. The method was applied to the analysis of four foods with recoveries from 85% to 110%, linearity correlation r>0.999, and precision RSD<10%. 12 elements in five SRM were also determined in good agreement with certified values.The method has the advantages of excellent sensitivity, precision, accuracy, simplicity of sample pretreatment, and less interference, which can meet demands of concerning standards for food and water quality analysis.