柱前衍生-液相色谱法测定食品中牛磺酸含量的不确定度评定

Evaluation of Uncertainty for the Taurine Content in Foods by High-Performance Liquid Chromatography with Pre-Column Derivatization

通过柱前衍生-高效液相色谱法测定奶粉中营养素牛磺酸的含量,根据实验过程和实验结果,评定牛磺酸检测结果的不确定度。通过定量方法建立数学模型,根据数学模型和实验步骤,分析整个实验过程的不确定度来源,计算合成相对不确定度和扩展相对不确定度。结果表明,标准溶液配制过程和重复性测量过程的不确定度贡献较大。在实际工作中,可以通过优化标准溶液的配制过程、减少重复测定误差来减小不确定度,提高检测结果的准确性。经过计算,当样品中牛磺酸的含量为39.4 mg/100 g时,其扩展不确定度为2.1 mg/100 g(k=2)。

The taurine content in milk powder was determined by high performance liquid chromatography(HPLC)with pre-column derivatization. The uncertainty of the determination results was evaluated according to the experimental process and experimental results. The mathematical model was established by quantitative method. The source of uncertainty was analyzed according to the mathematical model and experimental steps, and the synthetic uncertainty and extended uncertainty were calculated. The results showed that the preparation of standard solution and the repeatability measurement contributed greatly to the uncertainty of the determination results. In practical work, the uncertainty can be reduced and the accuracy of the test results can be improved by optimizing the preparation process of the standard solution and reducing the repeated measurement error. After calculation, when the taurine content in the sample was 39.4 mg/100 g, the extended uncertainty was 2.1 mg/100 g(k=2).