C反应蛋白正确度验证物质均匀性和稳定性及其互换性

The preparation and evaluation of CRP trueness verificator: homogeneity, stability and commutability

目的制备C反应蛋白(CRP)正确度验证物质并对其均匀性、稳定性及互换性进行评价。方法将临床验后样本混匀、过滤和无菌分装后制备了高、低两个浓度的CRP冰冻混合人血清正确度验证物质,利用中国合格评定国家认可委员会(CNAS)的相关文件CNAS-GL29∶2010《标准物质_标准样品定值的一般原则和统计方法》对其均匀性和稳定性进行评价;在10个临床常用的CRP检测系统中,将制备的正确度验证物质,利用45份不同CRP浓度患者血清盘,采用美国临床实验室标准协会(CLSI)EP30A中的Deming回归对其互换性进行评价。同时用同样的方法对CRP国际标准物质ERM-DA 474/IFCC稀释系列进行互换性评价。结果共制备CRP两个浓度水平正确度验证物质,高、低两个浓度水平分别为754和743支,每支1 ml。制备物均匀性良好[F<F0.05(14,30)];在常温及2~8 ℃条件下的7 d短期稳定性和-80 ℃条件下44个月的长期稳定性检验中,线性方程的斜率|b1|均小于t0.95,n-2·s(b1),斜率与0差异无统计学意义,稳定性良好。制备的两个浓度的CRP正确度验证物质、ERM-DA474/IFCC稀释系列与患者血清在10系统间具有良好的互换性。结论该CRP正确度验证物质具有良好的均匀性、稳定性和互换性。CRP国际标准物质ERM-DA474/IFCC稀释系列互换性良,为该正确度验证物质的定值及应用提供了实验支持。

Objective To prepare the trueness verification materials of C-reactive protein (CRP) and evaluate its homogeneity,stability and commutability.Methods The high and low CRP concentrations trueness verification materials were from patient leftover sera which were pooled,mixed thoroughly,filtered and aliquoted.The homogeneity,stability and commutability of these materials were evaluated according to CNAS(China National Accreditation Service for Conformity Assessment,CNAS)-GL29∶2010 "Reference materials -General and statistical principles for certification (ISO Guide35∶2006)" and the Clinical and Laboratory Standards Institute (CLSI) EP30A.The trueness verification materials were used to evaluate the commutability in 10 clinical CRP detection systems,using forty-five patients′ leftover sera with different CRP concentration evaluated by Deming regression in EP30A of CLSI.Meanwhile,the commutability of dilution series of ERM DA-474/IFCC were evaluated using the same method.Result sA total of two CRP concentration level trueness verification materials were prepared,with high and low concentration levels of 754 and 743 vials,1 ml each,respectively.The preparation showed good homogeneity (F<F0.05(14,30);On the condition of room temperature,2-8 ℃ and -80 ℃,these materials were stable for 7 days and 44 months respectively,the slope of the linear equation of | b1 | less than t0.95,n-2·s(b1),there was no statistically significant difference between the slope and zero,the stability is satisfied.The materials and the dilution series of ERM-DA 474/IFCC also showed good commutability among patient sera in 10 systems.Conclusion sThe trueness verification materials of C-reactive protein (CRP) showed good homogeneity,stability and commutability.The dilution series ERM DA-474/IFCC also have good commutability.These provided experimental support for the value transfer and application of the trueness verification materials.