HPLC测定茶叶中茶氨酸含量的不确定度评定

Uncertainty Evaluation of the Measurement of Theanine Content in Tea by HPLC

按照GB/T 23193-2017的规定,用高效液相色谱法对蒙顶甘露茶叶中茶氨酸含量进行检测,对茶氨酸含量的不确定度进行分析和评定,建立数学模型,分析样品的不确定度来源,推导出计算方法和步骤,建立了该试验方法的评定方式,找出不确定度的主要分量,以便在检测工作中予以改进。通过评定得出分析仪器带来的不确定度最大,标准曲线拟合和加标回收率带来的不确定度次之,故在测定时应加以控制。

According to the provisions of GB/T 23193-2017,theanine content of Mengding Ganlu tea were measured by high performance liquid chromatography in the current study,and a mathematical model had been established to analyze and evaluate the uncertainty evaluation of theanine content. To improve the future measurement work,by analyzing the source of the uncertainty of the sample and deducing the calculation method and steps,the evaluation method of the measurement was established,and the main component of the uncertainty was found. The evaluation results found that the uncertainty caused by the analytical instrument was the largest,followed by the standard curve fitting and the recovery rate of standard addition,which indicates that these main factors should be controlled during the measurement.