建立了电感耦合等离子体质谱(ICP-MS)法测定食品级磷酸盐中Mg, Ti, V, Cr, Fe, Co, Ni, Cu, Zn, As, Cd, Pb等12种杂质元素的分析方法。 样品经硝酸消解后直接进行分析, 应用碰撞/反应池(ORS)技术有效地消除了多原子离子对待测元素的干扰, 选用Sc, Y, In, Bi等元素为内标混合液校正基体干扰和漂移。 研究结果表明, 该方法对12种待测元素的检出限在0.004～0.362 μg·L-1之间。 本法简便, 快速, 能满足食品级磷酸盐中多种杂质元素同时测定的分析需求。

An octopole reaction system (ORS) inductively coupled plasma mass spectrometry (ICP-MS) was developed for the determination of Mg, Ti, V, Cr, Fe, Co, Ni, Cu, Zn, As, Cd and Pb in edible phosphate. The sample was digested by HNO3 followed by dilution with ultrapure water, then the above 12 impurity elements in the solution were analyzed directly by ICP-MS. The use of ORS can eliminate the interference of polyatomic ions dramatically. Sc, Y, In and Bi were used to correct the matrix interference and drift. The detection limits of the 12 elements are in the range of 0.004～0.362 μg·L-1. This method is rapid, simple and applicable for the analysis of trace elements in edible phosphate.