电感耦合等离子体质谱法测定糖果中铅含量的不确定度评定

Uncertainty evaluation of determination of lead in candy by inductively coupled plasma-mass spectrometry

中文关键词:  电感耦合等离子体质谱法  糖果  铅  不确定度  标准曲线  测量重复性

英文关键词:inductively coupled plasma-mass spectrometry  candy  lead  uncertainty  standard curve  measurement repeatability

中文摘要:

      目的 评定电感耦合等离子体质谱法(inductively coupled plasma-mass spectrometry, ICP-MS)测定糖果中铅含量的不确定度。方法 按照CNAS-GL006-2019《化学分析中不确定度的评估指南》及JJF 1059.1-2012《测量不确定度评定与表示》的要求和方法, 全面系统地分析整个实验过程中的不确定度因素, 计算各个不确定度分量及扩展不确定度。结果 糖果中铅含量为0.077 mg/kg, 置信概率为95%时, 测定结果中合成不确定度为0.0054 mg/kg, 扩展不确定度为0.011 mg/kg (k=2)。结论 标准曲线的拟合及测量重复性是糖果中铅含量测量不确定度的主要来源。

英文摘要:

      Objective To evaluate the uncertainty of determination of lead in candy by inductively coupled plasma-mass spectrometry(ICP-MS). Methods According to CNAS-GL006-2019 Guidance on quantifying uncertainty in chemical analysis and JJF 1059.1-2012 Evaluation and expression of uncertainty in measurement, the factors of the uncertainty in the process of the whole experiment was systematically analyzed, the results of the uncertainty and the expanded uncertainty were calculated. Results When the lead content in candy was 0.077 mg/kg and the confidence probability was 95%, the combined standard uncertainty was 0.0054 mg/kg, and the expanded uncertainty was 0.011 mg/kg (k=2). Conclusion The fitting linear regression equation for standard curve and measurement repeatability are predominant sources of uncertainty of measurement results for lead in candy.