5水平冰冻混合人血清尿酸候选二级标准物质的研制

Preparation of five frozen pooled human serum samples as secondary reference materials for uric acid

目的研制5水平尿酸(UA)冰冻混合人血清候选二级标准物质,为UA常规检测方法的准确度验证提供稳定和互通性良好的真实值控制品。方法收集无肉眼可见脂血、溶血和黄疸的5个UA浓度混合血清,过滤并分装后,-70℃保存。参照《标准物质/标准样品定值的一般原则和统计方法》(简称ISO Guide 35)用常规方法进行均匀性和稳定性研究。3家UA候选参考实验室对血清物质进行定值,定值结果用“靶值±总不确定度(uCRM)”表示。参照美国国家临床实验室标准委员会EP14-A2文件要求评价互通性。结果血清物质均匀性良好(P>0.05),瓶间变异均<1%。室温和4℃UA浓度的稳定性能满足日常使用需要,-20℃至少可稳定115 d,-70℃至少可稳定15个月。5水平物质的定值结果分别为(70.00±3.12)、(281.67±4.69)、(383.00±6.46)、(431.00±9.95)和(520.00±12.10)μmol/L。冰冻混合血清物质在15套UA常规检测系统中的互通性良好。结论研制的5水平冰冻混合人血清UA候选二级标准物质均匀性、稳定性、互通性良好,定值准确。

Objective To prepare five frozen pooled human serum samples as secondary reference materials for uric acid(UA),which were used to validate trueness of routine methods. Methods Five UA concentrations of fasting fresh serum samples without lipemia,hemolysisorcholoplania were collected selectively,mixed and centrifuged. The supernatants were filtrated,allotted,sealed and stored at-70 ℃. The homogeneity and stability of the five frozen pooled serum samples were evaluated according to Reference Materials-General and Statistical Principles for Certification(ISO Guide 35 for short). The materials were assigned values by three candidate reference laboratories. The fixed values of the five serum samples presented as target value ± total uncertainty(uCRM). Commutability of the five serum samples was assessed according to the National Committee for Clinical Laboratory Standards EP14-A2. Results The five frozen pooled serum samples were homogeneous(P>0.05),and the variation between bottles was less than 1%. The stability of UA concentration at room temperature and 4 ℃ could meet the needs of daily use. The samples were stable for at least 115 days at –20 ℃ and 15 months at –70 ℃. The fixed valuesof the five frozen pooled serum samples for UA were(70.00±3.12),(281.67±4.69),(383.00±6.46),(431.00±9.95) and(520.00±12.10) μmol/L. The five frozen pooled serum samples had good commutability among 15 routine analytical systems. Conclusion The fivefrozen pooled serum samples are homogeneous,stable,commutable and well assigned,which can be recommended as secondary reference materials for UA.