LAUSR

Abstract The spectroscopic parameters of the paramagnetic species produced in gamma-irradiated l -citrulline, α-methyl- dl -serine, 3-fluoro- dl -valine and N -acetyl- l -cysteine were investigated at room temperature at a dose of 20 kGy by using EPR technique. The paramagnetic species were attributed to NH 2 CONH(CH 2 ) 3 ĊNH 2 COOH, HOCH 2 ĊCH 3 COOH and HOĊHCCH 3 NH 2 COOH, CH 3 CH 3 ĊCHNH 2 COOH and SHCH 2 ĊNHCOCH 3 COOH radicals, respectively. EPR data of the unpaired electron with the environmental protons and 14 N nucleus were used to characterize the contributing radicals produced in gamma irradiated compounds. In this paper, the stability of these compounds at room temperature after irradiation was also studied.