Mechanism of photocatalytic oxidation of guanine by BiOBr under UV irradiation

This article analyzes the mechanism details of guanine photocatalytic oxidation on the surface of BiOBr nanoparticles under UV irradiation. The reaction of O2− with radical species, generated from primary oxidation of guanine by hole, is proposed to be the dominant cause of guanine damage. The present work demonstrates that BiOBr photocatalysis provided good model to investigate the reaction of substrate radical with the in situ formed O2−. It also implicates that the frequently-used biomarker for DNA damage 8-oxo-7,8-dihydro-2-deoxyguanosine (8-oxodG) may be ineffective in the situation that damage is caused by O2−.