Determination of bilirubin glucuronide and assay of glucuronyltransferase with bilirubin as acceptor

1. Conjugated bilirubin is conveniently determined by coupling with the diazonium salt of ethyl anthranilate. 2. This method has been used in the development of assays for UDP-glucuronyltransferase (EC 2.4.1.17), with bilirubin as substrate, in rat liver homogenates, microsomal preparations and partly purified fractions. 3. Chromatographic analysis suggests that bilirubin monoglucuronide is the product of the enzyme systems studied.