Studies on the Use of the van den Bergh Reagent for Determination of Serum Bilirubin

Abstract

Abstract 1. By increasing the concentration of hydrochloric acid, sulfanilic acid, and sodium nitrite in the van den Bergh reagent used for determining total serum bilirubin it is possible to increase the absorbance of azobilirubin and to accelerate its reaction time to less than 10 minutes. A modified reagent is proposed for the Malloy and Evelyn procedure. 2. The effects of temperature, urea, and protein on the coupling of serum bilirubin are discussed. 3. Hemolysis seriously affects the coupling of bilirubin. The decrease in azobilirubin production appears to vary directly with the amount of hemolysis. When the amount of hemolysis is constant, the decrease in azobilirubin production appears to vary inversely with the bilirubin concentration. The interfering effect of hemoglobin is unexplained.