Abstract:

Objective To develop the national standard materials of total bilirubin in frozen human serum,and to evaluate the accuracy and promote the standardization of total bilirubin assay. Methods Serum samples without hemolysis,jaundice and lipemia were collected. After multiple filtration sterilization,serum pools were packed in ampoules in 2-level candidate materials（Ⅰ and Ⅱ） and stored in -70 ℃. Homogeneity for candidate material was evaluated by single factor analysis of variance. The stability for candidate material was evaluated by linear regression analysis. The value for candidate material was assigned by reference method,and the uncertainty was calculated. The commutability was evaluated as well. Results The F values of homogeneity for candidate material level Ⅰ and level Ⅱ were 0.801 1 and 1.234 1,respectively. They were all <F_0.05. The stabilities of candidate material level Ⅰ and level Ⅱ can be last at least 30 and 5 d at -20 ℃,respectively. The assigned values of candidate material level Ⅰ and level Ⅱ were（7.01±0.28）μmol/L（k=2） and（27.10±0.54）μmol/L（k=2）,respectively. The values for candidate material level Ⅰ and level Ⅱ were all within 95% confidence intervals. Conclusions The homogeneity and commutability of candidate material are good. The stability of candidate material meets the requirement,and their values are assigned accurately and reliably. They can be used as national standard.

Key words: Total bilirubin, Frozen human serum, National standard