Effects of 60Co γ-irradiation on chondromucoprotein

Pulse radiolysis and 60Co γ-radiolysis have been used to study the effects of ionizing radiations on the protein-polysaccharide complex, chondromucoprotein. Both hydroxyl radicals and hydrated electrons readily reacted with the complex, with second-order rate-constants of 4.55 x 108 and 3.7 x 108 M-1s-1, respectively. Depolymerization of the carbohydrate component, which was initiated by the reaction of OH, readily occurred after irradiation in aqueous solutions, as was evidenced by an increase in the formation of reducing-end groups and a decrease in the viscosity of the solution. The ability of the anionic carbohydrate component to bind cationic counter-ions also decreased. (author)