Effects of Ionizing Radiations on Glucuronic Acid

Abstract

The effects of radical scavengers and solute concentration indicate that the degradation of glucuronic acid by60 Co γ-irradiation is mainly due to OH radicals. Pulse radiolysis demonstrates no significant reaction of sodium glucuronate with $e_{{\rm aq}}^{-}(k_{2}\leq 10^{6} M^{-1} \text{second}^{-1})$, but a facile reaction with OH radicals ( $k_{2}\sim 10^{9} M^{-1} \text{second}^{-1}$). Moreover, a transient intermediate is produced, which appears to be the result of OH radical abstraction and decays by second-order kinetics ( $k_{2}\sim 10^{7} M^{-1} \text{second}^{-1}$). Beyond $7.5\times 10^{-3} M$ solute concentration additional processes lead to glucuronic acid degradation, which cannot be accounted for on the basis of direct action effects. When irradiated in the solid state -G (glucuronic acid) = 4, but this is considerably reduced due to energy transfer if the p-toluidine-ammonium complex is irradiated.