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Updated: Jul 11, 2026

Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development
Published on: April 15, 2013
[Free radicals and their biological significance: present and future]
1Photon Medical Research Center, Hamamatsu University, School of Medicine, Japan.
Abstract:
Free radicals are usually active species which have unpair electron (S) in molecules or Atomic groups. Of the free radicals, O2- and .OH could easily be produced in mammalian cells, by oxidation and reduction cycle catalyzed by fravoproteins and by iron + H2O2 reaction, respectively. Other free radicals would also be produced in mammalian cell, such as amino acid radicals, semiquinone radicals and flavine radicals etc. In general, free radicals cause cell injury though membrane lipid peroxidation and DNA strand cleavage and some other mechanisms.
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