How to translate text using browser tools
1 November 2006 Ascorbate Reacts with Singlet Oxygen to Produce Hydrogen Peroxide
Galina G. Kramarenko, Stephen G. Hummel, Sean M. Martin, Garry R. Buettner
Author Affiliations +

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 × 108 M−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.

Galina G. Kramarenko, Stephen G. Hummel, Sean M. Martin, and Garry R. Buettner "Ascorbate Reacts with Singlet Oxygen to Produce Hydrogen Peroxide," Photochemistry and Photobiology 82(6), 1634-1637, (1 November 2006).
Received: 12 January 2006; Accepted: 1 August 2006; Published: 1 November 2006

This article is only available to subscribers.
It is not available for individual sale.

Get copyright permission
Back to Top