电感耦合等离子体质谱法测定保健食品(杞髓冲剂)中4种矿物元素的不确定度评定

目的评定电感耦合等离子体质谱法(ICP-MS)测定保健食品中锰、铁、锌、硒矿物元素的不确定度。方法根据JJF1059.1-2012《测量不确定度评定与表示》,分析测量不确定度分量的主要来源,对各不确定度分量进行评定和计算。结果在P=95%,k=2时,保健食品中锰、铁、锌、硒的含量分别为(23.8±1.8)、(102.0±8.4)、(21.0±1.8)和(0.0936±0.0092) mg/kg。通过对不确定度的来源分析及各分量的量化评定,标准曲线拟合引入的不确定度最大,其次是回收率、定容体积引入的不确定度分量。结论该研究可为实验室评定保健食品中锰、铁、锌、硒的测定结果质量提供参考。

Uncertainty evaluation for the determination of four mineral elements in health food (Qisui granule) by inductively coupled plasma mass spectrometry

Objective To evaluate the uncertainty of determination of manganese, iron, zinc and selenium in health food by inductively coupled plasma mass spectrometry (ICP-MS). Methods Based on the method of JJF1059.1-2012 National Technical Specification for Metrology-Evaluation and Expression of Uncertainty in Measurement, we evaluated the influences of key factors on the quantitative results. The composite and extended uncertainty were calculated. Results When P=95%, k=2, the concentration of manganese in health food was (23.8±1.8) mg/kg, iron was (102.0±8.4) mg/kg, zinc was (21.0±1.8) mg/kg, selenium was (0.0936±0.0092) mg/kg. Through the source analysis of uncertainty and quantitative evaluation of each component, the uncertainty introduced by standard curve fitting is higher than others. The second uncertainty was introduced by the recovery rate and constant volume. Conclusion The results provide a reference for the laboratory to evaluate the quality of determination results of manganese, iron, zinc and selenium in health food.