Detection of hydrogen atom adduct of spin-trap DEPMPO. The relevance for studies of biological systems.
We proposed EPR spectroscopy using spin-trap DEPMPO as a novel method for the detection of a hydrogen atom (*H) produced by chemical and biological systems. In complex EPR spectra of DEPMPO adducts in biological systems, spectral lines of unknown origin have been observed. We have assumed (Bacić, G.; Mojović, M. Ann. N. Y. Acad. Sci. 2005, 1048, 230-243) that those lines represent the spectrum of a hydrogen atom (*H) adduct i.e., DEPMPO/H. An electrochemical system known to produce only *H radicals was used here in order to obtain a separate spectrum of the DEPMPO/H adduct. An acquired spectrum as well as a computer spectral simulation of the DEPMPO/H adduct showed considerable resemblance with additional lines in the EPR spectra of DEPMPO adducts in biological systems-plant plasma membranes and cell walls. This shows that such a radical is produced by plants as well as that DEPMPO is suitable for detection in both electrochemical and biological systems.
Mojović
Milos
M
Faculty of Physical Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade.
Spasojević
Ivan
I
Bacić
Goran
G
D002462:Cell Membrane / Q000737:chemistry; D003497:Cyclic N-Oxides / Q000737:chemistry*; D004563:Electrochemistry; D004578:Electron Spin Resonance Spectroscopy; D006859:Hydrogen / Q000737:chemistry*; D010944:Plants / Q000737:chemistry / Q000648:ultrastructure; D013113:Spin Labels; D019097:Spin Trapping
D003497:Cyclic N-Oxides; D013113:Spin Labels; C098505:5-diethoxyphosphoryl-5-methyl-1-pyrroline N-oxide; D006859:Hydrogen