A simplified procedure for eliminating the negative interference of bilirubin in the Jaffé reaction for creatinine

Abstract

The negative interference by bilirubin in the measurement of creatinine by the Jaffé procedure is well documented. We describe a procedure for the elimination of interfering bilirubin by oxidation to biliverdin through the addition of potassium ferricyanide before the alkaline picrate reagent. We detected no negative interference with the addition of as much as 600 μmol/L bilirubin. The procedure shows good agreement with a recently described blank rate method for analyzing icteric samples.