Radiation and Environmental Biophysics

, Volume 23, Issue 4, pp 235-243

First online:

Hydrogen peroxide and hydroxyl radical formation by methylene blue in the presence of ascorbic acid

  • G. R. Buettner
  • , Th. P. Doherty
  • , Th. D. Bannister

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access


Using ESR we have demonstrated the formation of the ascorbate free radical from sodium ascorbate, methylene blue and light. In oxygen uptake experiments we have observed the production of hydrogen peroxide while spin trapping experiments have revealed the iron catalyzed production of the hydroxyl free radical in this system. The presence of this highly reactive radical suggests that it could be the radical that initiates free radical damage in this photodynamic system.