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. 1994 Sep;102(Suppl 3):11–15. doi: 10.1289/ehp.94102s311

Oxidizing intermediates generated in the Fenton reagent: kinetic arguments against the intermediacy of the hydroxyl radical.

D A Wink 1, C B Wink 1, R W Nims 1, P C Ford 1
PMCID: PMC1567375  PMID: 7843082

Abstract

It has long been recognized that the aqueous mixture of hydrogen peroxide and ferrous ion, known as the Fenton reagent, generates powerful oxidants. Furthermore, the chemical intermediates and reaction pathways of the type generated by this reagent have been implicated in oxidative damage in biological systems. Although the subject continues to be debated, the hydroxyl radical (.OH) is generally invoked as the predominant oxidizing intermediate formed by the Fenton reagent. However, recent results from this laboratory have demonstrated that the principal pathway for the Fenton-mediated oxidation of N-nitrosodimethylamine does not involve .OH, but instead must involve the intermediacy of another strongly oxidizing species. This conclusion was based on stopped-flow spectrophotometric observation of a transient, A, believed to be an iron(II) nitrosyl adduct, which was formed at a rate five-fold faster than that predicted for formation of .OH. Subsequent experiments have shown that methanol and other organic compounds can quench the formation of A. This quenching procedure provides a unique spectrophotometric probe with which to examine the relative reactivities of putative Fenton-type oxidizing intermediates toward organic substrates. Presented here are the results of several such quenching studies, plus an overview of our mechanistic investigations of the Fenton reaction.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Ames B. N., Cathcart R., Schwiers E., Hochstein P. Uric acid provides an antioxidant defense in humans against oxidant- and radical-caused aging and cancer: a hypothesis. Proc Natl Acad Sci U S A. 1981 Nov;78(11):6858–6862. doi: 10.1073/pnas.78.11.6858. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Halliwell B., Gutteridge J. M. Biologically relevant metal ion-dependent hydroxyl radical generation. An update. FEBS Lett. 1992 Jul 27;307(1):108–112. doi: 10.1016/0014-5793(92)80911-y. [DOI] [PubMed] [Google Scholar]
  3. Halliwell B., Gutteridge J. M. Oxygen free radicals and iron in relation to biology and medicine: some problems and concepts. Arch Biochem Biophys. 1986 May 1;246(2):501–514. doi: 10.1016/0003-9861(86)90305-x. [DOI] [PubMed] [Google Scholar]
  4. Halliwell B., Gutteridge J. M. Oxygen toxicity, oxygen radicals, transition metals and disease. Biochem J. 1984 Apr 1;219(1):1–14. doi: 10.1042/bj2190001. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Heur Y. H., Streeter A. J., Nims R. W., Keefer L. K. The Fenton degradation as a nonenzymatic model for microsomal denitrosation of N-nitrosodimethylamine. Chem Res Toxicol. 1989 Jul-Aug;2(4):247–253. doi: 10.1021/tx00010a006. [DOI] [PubMed] [Google Scholar]
  6. Imlay J. A., Chin S. M., Linn S. Toxic DNA damage by hydrogen peroxide through the Fenton reaction in vivo and in vitro. Science. 1988 Apr 29;240(4852):640–642. doi: 10.1126/science.2834821. [DOI] [PubMed] [Google Scholar]
  7. Jonas S. K., Riley P. A., Willson R. L. Hydrogen peroxide cytotoxicity. Low-temperature enhancement by ascorbate or reduced lipoate. Biochem J. 1989 Dec 15;264(3):651–655. doi: 10.1042/bj2640651. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Minotti G., Aust S. D. The requirement for iron (III) in the initiation of lipid peroxidation by iron (II) and hydrogen peroxide. J Biol Chem. 1987 Jan 25;262(3):1098–1104. [PubMed] [Google Scholar]
  9. Sutton H. C., Vile G. F., Winterbourn C. C. Radical driven Fenton reactions--evidence from paraquat radical studies for production of tetravalent iron in the presence and absence of ethylenediaminetetraacetic acid. Arch Biochem Biophys. 1987 Aug 1;256(2):462–471. doi: 10.1016/0003-9861(87)90603-5. [DOI] [PubMed] [Google Scholar]
  10. Wink D. A., Nims R. W., Desrosiers M. F., Ford P. C., Keefer L. K. A kinetic investigation of intermediates formed during the Fenton reagent mediated degradation of N-nitrosodimethylamine: evidence for an oxidative pathway not involving hydroxyl radical. Chem Res Toxicol. 1991 Sep-Oct;4(5):510–512. doi: 10.1021/tx00023a002. [DOI] [PubMed] [Google Scholar]

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