电位滴定法测定甘氨酸含量的不确定度评定

Evaluation of Measurement Uncertainty for Determination of Glycine by Potentiometric Titration

目的:评定《欧洲药典》中电位滴定法测定甘氨酸含量的不确定度,探讨影响甘氨酸含量测定的不确定度分量。方法:建立甘氨酸含量测定的数学模型。对甘氨酸含量测定的过程进行分析,分析各个过程引入的不确定度分量,并将各不确定度分量进行量化。最终合成得到甘氨酸含量测定的不确定度,并给出标准不确定度。结果:电位滴定法测定甘氨酸含量为99.43%,其标准不确定度为0.35%,扩展不确定度为0.70%,测量结果表示为(99.43±0.70)%。结论:建立了《欧洲药典》品种甘氨酸含量测量的不确定度评定方法,分析产生不确定度的主要来源,为有效控制甘氨酸含量的测定方法的准确性提供可靠的理论依据,并为参加欧洲药品质量管理局(EDQM)能力验证的实验室评定不确定度提供参考。

Objective:To establish uncertainty evaluation for the determination of glycine by potentiometric titration,and to discuss the uncertainty component that affects the determination of glycine content.Methods:The measurement model of glycine content determination was established.The process of glycine content determination was analyzed,the uncertainty component introduced by each process was analyzed,and the uncertainty component was quantifide.Finally the uncertainty of glycine content determination was synthesized,and the standard uncertainty was given.Results:The content of glycine was 99.43%,and standard uncertainty was 0.35%,and the determination result was(99.43±0.35)%.Conclusion:The method of the uncertainty evaluation for the determination of glycine is established.The main sources of uncertainty are analyzed,which provide the reliable theoretical basis for effectively controlling of this method.It also provides a reference for the evaluation uncertainty of laboratories participating in EDQM proficiency testing.