Effects of bilirubin on detection of hydrogen peroxide by use of peroxidase

Bilitubin interferes with the quantitation of hydrogen peroxide in reagent systems in which peroxidase is used. Difference spectra suggest that this interference is a combination of chemical and spectral effects. The data presented are most consistent with the following interpretation: (a) bilirubin destroys part of the reactive intermediate formed in the peroxidase reaction and thus decreases the amount of chromophore formed and (b) the spectra for bilirubin and the chromaphore overlap, which also affects the results. The relevance of these results to reagent design and laboratory quality control are discussed.