改良双缩脲法测定血清总蛋白

Measurement of serum total protein by improving biuret method

目的研究建立改良双缩脲试剂二点速率法测定血清总蛋白的方法,以消除标本溶血、黄疸、脂浊、含葡聚糖的干扰。方法进行方法参数选择试验、方法学评价试验和方法间比较试验。结果改良试剂反应液吸收峰530～560nm,最大峰值540nm。在反应进行的初期,吸光度变化率与蛋白质浓度成正比,可用速率法测定,线性范围142g/L。高、低值血清的批内、批间、日间和总CV均<5%。回收率为98.6%～100%,平均99.3%。检测限0.4g/L。血红蛋白9.5g/L以下、胆红素370μmol/L以下、三酰甘油200.0mmol/L以下、葡聚糖30g/L以下无显著性干扰。改良法与Doumas法测定外观正常标本结果高度相关,回归方程:y=2.7147+0.9658x,r=0.9633,P=0.000。配对t检验:t=0.907,P=0.370。测定高脂、黄疸、含葡聚糖标本两种方法间有非常显著性差异。结论采用改良法单试剂二点速率法测定血清总蛋白,能有效消除溶血、黄疸、高脂和葡聚糖的干扰。

Objective To investigate a new methed of measuring serum total protein by improving biuret reagent through two point velocity method in order to dissolve the sample′s interference of hemolysis, icterus, lipid,polymeric glucose.Methods Many experiments were done, which included method parameter choice experiment, methodology evaluation experiment and comparison experiment between methods.Results The absorption peak was between 530 and 560 nm, and the maximum absorption was 540nm. In the first stage of the reaction, the absorption variational rate was directly proportional to the concentration of the protein, which could be measured by velocity method. The linear scope was 142g/L. The serums CV of high and low value were all less than 5%, include inside and between the group , daytime and total CV.The recovery rate was 98.6%-100% , average 99.3%. The measure limit was 0.4g/L. The interference was not significant when Hb was lower than 9.5g/L,bil lower than 370μmol/L,TG lower than 200.0mmol/L and polymeric glucose lower than 30g/L.While measuring normal sample, improving method and Doumas method were highly correlation. Regress equation: y =2.714 7+0.965 8x,r=0.963 3,P=0.000.Partnership t examination:t=0.907,P= 0.370.While measuring samples of lipid, icterus and polymeric glucose, there was a significant reference between the two methods.Conclusion It could dissolve effectively the sample′s interference of hemolysis, icterus, lipid, polymeric glucose while adopting improving single reagent through two point velocity method.