A Specific Method for Quantitative Determination of Unconjugated Bilirubin and Mesobilirurin

Abstract

Principles for quantitative determination of unconjugated bilirubin are reviewed. A method is developed, based upon chloroform extraction in the cold at pH 8 after addition of ascorbic acid and salicylic acid. Carotenoids, if present, may be removed by preceding extraction with petroleum ether. The procedure may be used for determination of mesobilirubin in mixtures with bilirubin. The reproducibility, recovery of added bilirubin and mesobilirubin, and the specificity are investigated. The method is suitable for determination of unconjugated serum bilirubin concentrations as low as 1 μM (0.06 ing/100 ml).