高效液相色谱法测定婴幼儿配方乳粉中维生素A含量的不确定度评定

Evaluation of Uncertainty in the Determination of Vitamin A in Infant Formula Powder by High-Performance Liquid Chromatography

依据《测量不确定度评定与表示》(JJF 1059.1—2012),结合高效液相色谱法测定婴幼儿配方乳粉中维生素A含量的结果计算公式,建立不确定度的数学模型,对测量过程中的各个不确定度分量进行来源归类、分量计算和合成计算。当取样量为5.0000g时,样品中维生素A的扩展不确定度为16μgRE/100g,测定含量为(369±16)μgRE/100 g。结果显示,标准物质配制成标准工作溶液对维生素A测定结果的不确定度贡献最大,测量结果重复性引入的不确定度次之。

According to JJF 1059.1—2012,combined with the results obtained from high-performance liquid chromatography for determining the vitamin A content in infant formula powder,a mathematical model for uncertainty was established.The various components of uncertainty in the measurement process were classified,quantified,and synthesized.When the sampling volume was 5.0000 g,the expanded uncertainty of vitamin A content in the sample was 16μgRE/100 g,with a measured value of(369±16)μgRE/100 g.The results indicated that the preparation of the standard working solution from the standard substance contributed the most to the uncertainty of the vitamin A determination,followed by the uncertainty introduced by the repeatability of the measurement results.