Journal article
Ascorbate Reacts with Singlet Oxygen to Produce Hydrogen Peroxide
Photochemistry and photobiology, Vol.82(6), pp.1634-1637
11/2006
DOI: 10.1562/2006-01-12-RN-774
PMCID: PMC2147043
PMID: 16898858
Abstract
Singlet oxygen is a highly reactive electrophilic species that reacts rapidly with electron-rich moieties, such as the double bonds of lipids, thiols, and ascorbate (AscH−). The reaction of ascorbate with singlet oxygen is rapid (k = 3 × 108M−1 s−1). Here we have investigated the stoichiometry of this reaction. Using electrodes to make simultaneous, real-time measurements of oxygen and hydrogen peroxide concentrations, we have investigated the products of this reaction. We have demonstrated that hydrogen peroxide is a product of this reaction. The stoichiometry for the reactants of the reaction (11O2 + 1AscH− → 1H2O2 + 1dehydroascorbic) is 1:1. The formation of H2O2 results in a very different oxidant that has a longer lifetime and much greater diffusion distance. Thus, locally produced singlet oxygen with a half-life of 1 ns to 1 μs in a biological setting is changed to an oxidant that has a much longer lifetime and thus can diffuse to distant targets to initiate biological oxidations.
Details
- Title: Subtitle
- Ascorbate Reacts with Singlet Oxygen to Produce Hydrogen Peroxide
- Creators
- Galina G Kramarenko - University of IowaStephen G Hummel - Free Radical and Radiation Biology and The University of lowa, lowa City, IASean M Martin - University of IowaGarry R Buettner - Free Radical and Radiation Biology and The University of lowa, lowa City, IA
- Resource Type
- Journal article
- Publication Details
- Photochemistry and photobiology, Vol.82(6), pp.1634-1637
- DOI
- 10.1562/2006-01-12-RN-774
- PMID
- 16898858
- PMCID
- PMC2147043
- NLM abbreviation
- Photochem Photobiol
- ISSN
- 0031-8655
- eISSN
- 1751-1097
- Number of pages
- 4
- Language
- English
- Date published
- 11/2006
- Academic Unit
- Radiation Oncology
- Record Identifier
- 9984313080602771
Metrics
18 Record Views