A candidate reference method for determination of bilirubin in serum. Test for transferability

Abstract

Each of 10 laboratories, using portions of a single crystalline bilirubin preparation, prepared bilirubin standards in solutions of bovine serum albumin. The standards were prepared on two days. The standards and two control sera were analyzed by a modified Jendrassik-Grof method, in duplicate, on the same day the standards were prepared. The mean molar absorptivity of the alkaline azobilirubin at 598 nm was 75 080 L mol-1cm-1 with a standard deviation of 760. Mean values for the two controls were 41.4 and 113.5 mg/L, with standard deviations of 0.9 and 1.4 mg/L, respectively.