肌酐纯度标准物质的定值方法及其不确定度评定研究

通过定性及定量分析,研究了肌酐纯度标准物质的定值方法,并进行了定值分析的不确定度评定。首先使用三重四极杆质谱仪及核磁共振谱仪(氢谱)对肌酐样品进行定性分析,然后采用质量平衡法(包括液相色谱法、水分、灰分、挥发性物质和无机元素分析)与定量核磁共振法共同对肌酐纯度标准物质进行准确定值,最后对定值结果进行不确定度评定。肌酐的定值结果为99.7%,扩展不确定度为0.4%。该研究对于实际检测中肌酐的准确测定及临床上相关疾病的正确诊断治疗具有重要意义,且经过定值的肌酐纯品还可做定量核磁共振法的定量内标使用。定量分析后的肌酐经过均匀性检验和稳定性考察后可申报为国家标准物质。

Research on a Certified Reference Material for Purity of Creatinine and Its Uncertainty Evaluation

A determination method for purity of creatinine was developed through qualitative analysis,quantitative analysis and uncertainty evaluation.The chemical composition of creatinine sample was determined by liquid chromatography-tandem mass spectrometry(LC-MS/MS) and nuclear magnetic resonance spectrometry(NMR) at first,and then the certified value was studied by mass balance method(including analysis of liquid chromatography,water content,ash content,volatile material and inorganic elements) and quantitative nuclear magnetic resonance(qNMR) method as well.The certified value of creatinine was 99.7%,with the expanded uncertainty of 0.4%.The research is important for correct diagnosis and treatment since it could assure the accuracy of determination of creatinine in Lab.The certified value of creatinine was so far as to use as the internal standard for qNMR.A certified reference material(CRM) for purity of creatinine was developed after homogeneity and stability study.