总蛋白改良参考方法的建立及其用于临床检测结果的溯源性研究

摘要

目的：建立测量总蛋白（TP）参考方法，评价不同实验室 TP测定结果的溯源性。方法参照美国疾病控制与预防中心推荐的参考方法及相关文件，建立37℃温浴10 min的总蛋白参考方法。根据美国临床实验室标准化协会系列文件对方法的精密度、正确度、线性范围等性能进行评价。应用该参考方法对新鲜血清进行赋值作为校准品校准广州21家实验室，比较校准前、后赋值血清校准品、血清样本测定结果间的偏移，进行检验结果的可比性评价。结果改良参考方法的精密度评价样本浓度为55．48、88．68 g／L的 CV分别为0．56％、1．23％，标准参考物质909C与靶值的偏移为1．76％，分析测量范围上限128．69 g／L。与参考方法测量结果比较，赋值血清校准品校准前平均偏移为6．38％，校准后降为1．86％，样本血清1、2校准前偏移分别为6．04％和8．71％，校准后降为－1．61％、－0．13％。结论改良的双缩脲法测量T P方法性能好，应用参考方法对新鲜血清进行赋值能够实现不同检测系统结果的溯源性。%Objective To establish a reference method for detecting the serum total protein (TP) and to evalu‐ate the traceability of the TP detection results by different laboratories .Methods The improved reference method of 10 min warm bath at 37 ℃ for detecting TP was established in accordance with the reference method recommended by the US Centers for Disease Control and Prevention and the related documents .The performance of accuracy ,preci‐sion ,linear range was evaluated according to the American Association of Clinical Laboratory Standardization .This reference method was used to conduct the value assignment on fresh as serum calibrator for adjusting 21 laboratories in Guangzhou .The bias of detection results in the assignment serum calibrators and serum samples were compared between before and after calibration .The feasibility evaluation of detection results was performed .Results In the precision evaluation by the improved reference method ,the coefficients of variation(CV) for two different concentra‐tions of 55 .48 and 88 .68 g/L were 0 .56% and 1 .23% respectively ,the shift of standard reference substance 909C and the target value was 1 .76% ,the upper limit of analytical detection range was 128 .69 g/L .Compared with the de‐tection results by the reference method ,the average shift of the assignment serum calibrator before calibration was 6 .38% ,which after calibration was decreased to 1 .86% ,the shifts of sample serum 1 and 2 before calibration were 6 .04% and 8 .71% respectively ,which after calibration were decreased to -1 .61% and -0 .13% respectively .Con‐clusion The improved biuret method has good performance for detecting TP .Using the reference method for conduc‐ting the value assignment on fresh serum can realize the traceability of results by different detection systems .