A demonstration that O2- is a crucial intermediate in the high quantum yield luminescence of luminol

The chemiluminescence of luminol, due to its reaction with alkaline H2O2, is inhibited by superoxide dismutase or by hydroxyl radical scavengers. Hematin markedly enhances this H2O2-induced luminescence of luminol and lessens, but does not eliminate, the sensitivity towards these inhibitors. Reaction mechanisms are proposed to account for these results. Since luminol luminescence depends upon a reaction between the luminol radical and O2-, and since the luminol radical can reduce dioxygen to O2-, superoxide dismutase-inhibitable luminol luminescence cannot be reliably used as a detector of O2- production.