Abstract: The uncertainty in the determination of nicotinamide in milk powder by ultra-high performance liquid chromatography was evaluated. According to the technical normal “Evaluation and Expression of Uncertainty in Measurement” (JJF 1059.1-2012), a mathematical model was established, and the source of each uncertainty component in the mathematical model was analyzed and calculated. The results showed that the uncertainty in nicotinamide determination mainly came from the dilution of the standard solution. In addition, the average content of nicotinamide in milk powder was 5 007 μg/100 g with an expanded uncertainty of about 197 μg/100 g (k = 2).

Key words: ultra-high performance liquid chromatography; milk powder; nicotinamide; uncertainty evaluation

摘要： 评定超高效液相色谱法测定乳粉中烟酰胺含量的不确定度。参照JJF 1059.1—2012《测量不确定度评定与表示》标准建立数学模型, 对数学模型中各不确定度分量的来源进行分析并计算。结果表明, 标准溶液的稀释定容过程是烟酰胺含量测定结果不确定度的主要来源, 当烟酰胺含量的平均测定结果为5 007 μg/100 g时, 其扩展不确定度约为197 μg/100 g（k=2）。

关键词: 超高效液相色谱法；乳粉；烟酰胺；不确定度评定