Free Radical-induced Cross-linking of Polydeoxythymidylic Acid in Deoxygenated Aqueous Solution

Summary

Radiation-generated hydroxyl radicals and hydrogen atoms were shown to induce the cross-linking of polydeoxythymidylic acid (mol wt ∼ 170 000) in N₂O-saturated acqueous solution. The irradiated samples were hydrolysed with formic acid and then analysed by high performance liquid chromatography. Products were isolated and subsequently characterized by capillary gas chromatography–mass spectrometry. The presence of previously described monomeric thymine products was also shown. Yields were determined and mechanisms of formation were described for the products.

• cross-linking
• DNA
• free radical
• gas chromatography–mass spectrometry