SINGLET MOLECULAR-OXYGEN IN THE HABER-WEISS REACTION

Characteristic chemiluminescence emission of singlet ((1) Delta(g)) mo lecular oxygen at 1268 nm is reported from a Haber-Weiss reaction. The reaction consists of mixing aqueous hydrogen peroxide with a solution of potassium superoxide, solubilized by 18-crown-6 ether in carbon te trachloride or in dry acetonitrile at room temperature. Since the disc overy of the enzyme superoxide dismutase by J. M. McCord and I. Fridov ich [(1968) J. Biol. Chem. 243, 5733-5760], the identity of the reacti ve oxidant in superoxide-generating systems in biology has remained a chemical mystery. The results presented here suggest strongly that the reactive species is singlet oxygen generated via the Haber-Weiss reac tion and not, as usually assumed, the hydroxyl radical, (OH)-O-., gene rated by the same reaction.