title: Spin-trapping of superoxide ion by a water-soluble, nitroso-aromatic spin-trap.
abstract: Spin-trapping of superoxide ion, O2-, which is produced from two different sources (OH(-)-DMSO and xanthine-xanthine oxidase systems), was investigated by use of a water-soluble, notroso-aromatic spin trap, sodium 3,5-dibromo-4-nitrosobenzene-sulfonate (DBNBS). It was found that O2- from all sources was easily trapped by DBNBS to yield the stable O2- adduct showing the ESR spectrum consisting of a triplet of a triplet [aN (1) = 12.63 G and aH (2) = 0.71 G]. Hydroperoxy radical (HO2.), which can be generated from the oxidation of hydrogen peroxide with Ce4+ ion, was not trapped by DBNBS. These results indicate that the trapped radical is O2-, but not HO2..
mesh_terms: D001557:Benzenesulfonates; D055598:Chemical Phenomena; D002621:Chemistry; D004121:Dimethyl Sulfoxide; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D006878:Hydroxides; D017665:Hydroxyl Radical; D007700:Kinetics; D009603:Nitroso Compounds; D012996:Solutions; D013113:Spin Labels; D013481:Superoxides; D014867:Water; D019820:Xanthine; D014969:Xanthine Oxidase; D014970:Xanthines
chemical_list: D001557:Benzenesulfonates; D005609:Free Radicals; D006878:Hydroxides; D009603:Nitroso Compounds; D012996:Solutions; D013113:Spin Labels; D014970:Xanthines; D014867:Water; D013481:Superoxides; D019820:Xanthine; D017665:Hydroxyl Radical; C048757:3,5-dibromo-4-nitrosobenzenesulfonate; D014969:Xanthine Oxidase; D004121:Dimethyl Sulfoxide