The spin trapping of superoxide and hydroxyl free radicals with DMPO (5,5-dimethylpyrroline-N-oxide): more about iron.
The reaction of superoxide with the spin trap DMPO (5,5-dimethylpyrroline-N-oxide) is widely used to study superoxide production as well as issues associated with the superoxide-related formation of hydroxyl radical. However, the interpretation of observed intensities of DMPO/.OOH and DMPO/.OH signals in electron paramagnetic resonance spin trapping experiments is not without its difficulties. In this paper, I report experiments that demonstrate: 1. That the flux of superoxide formation in a DMPO spin trapping experiment can alter the apparent importance of weak DMPO/.OH signals; 2. That iron can influence the DMPO/.OOH spin trapping results; 3. That there is very little spontaneous breakdown of DMPO/.OOH to form DMPO/.OH.
Buettner
G R
GR
ESR Facility/EMRB 68, College of Medicine, University of Iowa, Iowa City 52242.
D003497:Cyclic N-Oxides / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D006878:Hydroxides / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D010545:Peroxides / Q000737:chemistry; D013113:Spin Labels; D013481:Superoxides / Q000737:chemistry*
D003497:Cyclic N-Oxides; D005609:Free Radicals; D006878:Hydroxides; D010545:Peroxides; D013113:Spin Labels; D013481:Superoxides; C017245:5,5-dimethyl-1-pyrroline-1-oxide; D007501:Iron