Possible Interaction: Hydrogen Peroxide and Cobaltous Cation

“Treatment of … DNA with Co(II ) at … M hydrogen peroxide resulted in a dose-dependent increase in 8-OHdG, which culminated at 25 µ M Co(II) (62.6 modified/…) and declined at higher Co(II) concentrations [9.6 modified/10 5 dG at 250 µ M Co(II)].”

“Regarding direct genotoxic mechanisms, Co(II ) induces the formation of reactive oxygen species when combined with hydrogen peroxide in cell-free systems.”

“DNA damage in chromatin caused by Ni(II) and Co(II ) ions in the presence of H2O2 may contribute to the established genotoxicity and carcinogenicity of these metal ions.”

“This method is based on the inhibition effect of atrazine (the oxidation of sulfanilic acid (SA) by hydrogen peroxide in the alkaline medium in the presence of the Co2+ ion).”

“Furthermore, Co2+ was found to be an uncompetitive inhibitor of H2O2.”

“ Co(II ) induced strong DNA cleavage in the presence of hydrogen peroxide even without alkali treatment.”

“ESR studies using 2,2,6,6-tetramethyl-4-piperidone as a singlet oxygen trap suggest that Co(II ) reacts with hydrogen peroxide to produce singlet oxygen or its equivalent.”

“The results suggest that Co(II) ion binds to DNA and subsequently reacts with hydrogen peroxide to produce singlet oxygen and hydroxyl radicals and that singlet oxygen plays a more important role in the DNA damage than hydroxyl free radicals.”