Effect of γ-rays on Thymine in De-aerated Aqueous Solutions

Abstract

IT is well known that X-irradiation of the pyrimidine bases in aqueous solutions in the presence of oxygen causes peroxidation at the position of the 4–5 double bond^1,2. It has been established, however, that in the absence of oxygen this reaction does not take place, and that the destruction of the bases is considerably reduced. This communication is concerned with the identification of the products formed under these latter conditions. γ-Irradiated deaerated solutions of thymine subjected to ion exchange column chromatography (‘Dowex 50 H⁺’) showed two peaks, the second of which has been identified as unreacted thymine (Fig. 1B) and the first presumed to contain the products of radiolysis (Fig. 1A).