高效液相色谱法测定乳粉中维生素K1含量不确定度评定

Evaluation of the measurement uncertainty of vitamin K1 content in milk power by high performance liquid chromatography

中文关键词:  测量不确定度  扩展不确定度  维生素K1  高效液相色谱仪

英文关键词:measurement uncertainty  expanded uncertainty  vitamin K1  high performance liquid chromatography

中文摘要:

      目的 评定高效液相色谱法(high performance liquid chromatography, HPLC)测定奶粉中维生素K1的测量结果的不确定度。方法 分析与量化高效液相色谱法测定奶粉中维生素K1的实验过程, 对标准物质、样品前处理、测量重复性及分析仪器等方面进行不确定度分析, 建立数学模型, 通过检测奶粉样品来计算测定结果的扩展不确定度。结果 HPLC测定奶粉中得到维生素K1含量的测定结果的扩展不确定度为1.68 μg/100 g, 奶粉中维生素K1含量的测定结果为(65.5±1.68) μg/100 g。结论 在维生素K1含量测定过程中, 最小二乘法拟合曲线产生的不确定度在该法中影响最大, 即标准溶液曲线所涉及到的浓度值是影响测量不确定度的主要因素, 故在样品测定时应对其加以控制, 提高检测结果的可靠性, 增强测量结果之间的可比性。

英文摘要:

      Objective To evaluate the measurement uncertainty of vitamin K1 content in milk power by high performance liquid chromatography (HPLC). Methods The process of determination of vitamin K1 in milk powder by high performance liquid chromatography was analyzed and quantified. Uncertainty analysis of reference materials, sample preparation, measurement repeatability, and analytical instruments were conducted. A mathematical model was established and the extended uncertainty of the measurement result was calculated by detecting the milk powder sample. Results The expanded uncertainty of vitamin K1 content was 1.68 μg/100 g. The content of vitamin K1 in milk power was (65.5±1.68) μg/100 g. Conclusions In the process of measuring vitamin K1 content, the uncertainty caused by the least squares fitting curve has the greatest influence in the method. That is, the concentration value involved in the standard solution curve is the main factor affecting the measurement uncertainty. Therefore, it should be controlled during sample measurement to improve the reliability of the test results and enhance the comparability between the measurement results.