1973 Volume 85 Issue 5-6 Pages 161-164
Direct bilirubins in vivo was fractionated into bilirubin diglucuronide, bilirubin phosphate and bilirubin sulfate. Influence of pH concentration on the absorptions maximum of each azo-pigment was studied. The schift of absorptions maximum was the same in the former two direct bilirubins and the latter moved as nearly as the indirect bilirubin-azo pigment yielded after an addition of methanol. These results was supposed to the difference was based on the structual difference of bilirubin due to the conjugation type of bilirubin.