血清尿酸紫外分光光度参考方法的建立及性能评价

目的以尿酸酶紫外光度法为基础,建立血清中尿酸测定的参考方法并评价其性能.方法 用新鲜患者血清样本、迈瑞常规复合校准品等对方法的精密度进行评估;用有证参考物质SRM909bⅠ和Ⅱ、IFCC参考实验室质评样本Rela A/B对方法的准确度进行初步评价,同时测定新鲜人血清并与同位素稀释质谱法进行方法学对比,验证方法准确度.结果 方法对新鲜患者血清、厂家复合校准品等不同类型样本批内不精密度CVintra小于1%,总不精密度CVt小于2%;有证参考物质SRM909bⅠ/Ⅱ测定结果均在参考值范围内,对UA参考实验室能力验证样本Rela A/B测定结果与中心值结果相对偏差小于0.5%;血清样本测定结果与同位素稀释液相质谱法可比,线性回归斜率1.005,相关系数0.999,医学决定水平处引入的相对误差小于3.25%.结论 血清尿酸紫外分光光度法已基本建立,精密度和准确度符合要求,测量结果和同位素稀释液相色谱/质谱法可比,可为常规系统尿酸溯源体系的建立和性能评估提供便捷有效的方法.

Development and evaluation of reference method for the detection of serum uric acid based on ultraviolet colorimetric method

Objective To develop a reference method for the detection of serum uric acid based on enzymic ultraviolet colorimetric and evaluate its performance.Methods Method precision was evaluated with fresh patient serum, Multi Serum Calibrator and other materials. Method accuracy was investigated with SRM909b level I, level II from the National Institute of Standards (NIST) and EQA sample Rela A/B for reference laboratory, and the method was compared with ID-LC/MS/MS for further validation.Results CVintra of method precision was less than 1% and CVt was less than 2% for different type of samples. Method accuracy was proved to good for the detection of SRM909b,Rela A/B, and the results fell in the range of target value, with relative bias less than 0.5%, compared with the result of reference laboratory for the detection of Rela samples. The method comparison with ID-LC/MS/MS showed fine correlation (r>0.99,slope=1.005) and the estimated error for medicine decide level (MDL) by this enzymic colorimetric method was less than 1%.Conclusion The reference method was established basically. Analytic characteristics such as precision and accuracy were conformed to meet the requirements. The established enzymic ultraviolet colorimetric reference methods could be used as a convenient and effective method for the establishment of traceability and performance evaluation for the determination of uric acid in routine system.