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Updated: Jun 4, 2026

Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development
Published on: April 15, 2013
A new trick (hydroxyl radical generation) for an old vitamin (B12)
Thomas A Shell1, David S Lawrence
1Department of Chemistry, Division of Medicinal Chemistry and Natural Products, University of North Carolina, Chapel Hill, North Carolina 27599, United States. tshell@email.unc.edu
Abstract:
Photolysis of hydroxocobalamin in the presence of plasmid DNA (pBR322) results in DNA cleavage. Temporal control of hydroxyl radical production and DNA strand scission by hydroxocobalamin was demonstrated using a 2-deoxyribose assay and a plasmid relaxation assay, respectively. The light-driven hydroxocobalamin-mediated catalytic formation of hydroxyl radicals was demonstrated using radical scavenging studies of DNA cleavage and via recycling of a hydroxocobalamin-resin conjugate several times without loss of efficacy.
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