A simple colorimetric method for the estimation of plasma biliverdin.

A new colorimetric method for the assay of biliverdin in biological fluids is described. The method, based upon the reaction of biliverdin with barbituric acid, offers improved sensitivity and selectivity when compared to direct spectrophotometric measurements. Using this method biliverdinaemia was observed in two patients with obstructive jaundice of malignant origin.