高效液相色谱法测定八宝粥罐头中乙二胺四乙酸二钠的不确定度分析

目的评定高效液相色谱法测定八宝粥罐头中乙二胺四乙酸二钠含量的不确定度。方法结合CNAS-GL06-2006《化学分析中不确定度的评估指南》和JJF 1059.1-2012《测量不确定度评定与表示》中规定的基本程序,分析了测量不确定性的来源,计算了测量结果的相对扩展不确定度。结果八宝粥罐头中乙二胺四乙酸二钠的含量为0.1172 g/kg,相对扩展不确定度为5.0%,测定结果可表示为X=(0.1172±0.0059)g/kg,k=2。在影响检测结果的6个不确定度分量中,标准工作溶液曲线拟合求浓度和样品前处理过程引入的不确定度是对结果影响较大的2个不确定度分量。结论可通过减少这些不确定度分量提高测量结果的质量,对实际工作中提高测量结果的准确性有一定的指导意义。

Uncertainty evaluation of the determination of EDTA-2Na in canned eight-ingredient porridge by high performance liquid chromatography

Objective To evaluate the uncertainty of determination of EDTA-2Na in canned eight-ingredient porridge by high performance liquid chromatography. Methods According to the uncertainty assessment described in CNAS-GL06-2006 Guidance on evaluation the uncertainty in chemical analysis and JJF 1059.1-2012 Evaluation and expression of uncertainty in measurement, the components of uncertainty in the measuring process were studied and analyzed, and the related expanded uncertainty was calculated and evaluated. Results The results of method showed the content of EDTA-2Na in canned eight-ingredient porridge was 0.1172 g/kg, the related expanded uncertainty was 5.0%, and the determination result was X=(0.1172±0.0059) g/kg, k=2. Among the 6 factors of uncertainty, the content of targeted ions from liners fitting and sample preparation were the main factors which influenced the results mostly. Conclusion Through reducing the amounts of these factors, the quality of the determination results can be increased. This evaluation methods is important to enhance the scientifically of measurement actually.