Detection of free radicals in gamma-irradiated seasnail hard tissues by electron paramagnetic resonance

Abstract

Gamma-irradiated seasnail (from family of Helix lukortium) hard tissues (CaCO3) were investigated by electron paramagnetic resonance (EPR) at room temperature. The radicals produced by gamma-irradiation in seasnail were attributed to orthorhombic C-. O-2(-), freely rotating C-. O-2(-), orthorhombic C-. O-3(-), axial C-. O-3(-), and axial C-. O-3(3-) free radicals. Unirradiated seasnail hard tissues also feature Mn2+ ions in their EPR spectra. The hyperfine values were determined for the C-13 nucleus in the orthorhombic C-. O-2(-) and axial C-. O-3(3-) free radicals and for the manganese impurity ions. The g values of all the free radicals have been measured. The results were compared with the literature data for similar defects. (C) 2003 Elsevier Ltd. All rights reserved.