Formation of singlet oxygen from solutions of vitamin E

Dad, S, Bisby, RH, Clark, IP and Parker, AW 2006, 'Formation of singlet oxygen from solutions of vitamin E' , Free Radical Research, 40 (3) , pp. 333-338.

Full text not available from this repository. (Request a copy)


Vitamin E offers protection against oxidative stress and is an efficient quencher of singlet oxygen. A recent report suggests that photo-excitation of vitamin E results in the formation of a triplet state (Naqvi et al. Photochem Photobiol Sci 2, 381 (2003)). This leads to the possibility of the triplet state of vitamin E being able to sensitize singlet oxygen and if this is the case it would be counter productive in terms of the biological protective function of vitamin E. We report the production of singlet oxygen, detected by 1270 nm luminescence, from pulsed laser excitation (308 nm) of vitamin E and an analogue, 2,2,5,7,8-pentamethyl-6-hydroxy-chroman (PMHC), with quantum yields between ~0.1 and 0.2. The luminescence was identified as singlet oxygen from self-quenching by vitamin E with solvent-dependent rate constants similar to published values. Whilst the beneficial antioxidant aspects of vitamin E are well established, these results indicate that vitamin E when directly excited can sensitize singlet oxygen formation and may, therefore, be capable of inducing biochemical and biological damage. The results are discussed in relation to recent reports on the deleterious effects of vitamin E dietary supplementation and pro-oxidant effects of vitamin E.

Item Type: Article
Themes: Subjects / Themes > Q Science > Q Science (General)
Subjects outside of the University Themes
Schools: Schools > School of Environment and Life Sciences
Schools > School of Environment and Life Sciences > Biomedical Research Centre
Journal or Publication Title: Free Radical Research
Publisher: Routledge Taylor & Francis
Refereed: Yes
ISSN: 10715762
Depositing User: H Kenna
Date Deposited: 08 Aug 2007 10:59
Last Modified: 27 Aug 2021 21:59

Actions (login required)

Edit record (repository staff only) Edit record (repository staff only)