Dynamic study of photosensitized one-electron oxidation of polyG by menadione

The electron transfer reaction of triplet menadione (3MQ*) with polyguanylic acid (polyG) in CH3CN rich (97%) solution was investigated by 248 nm(KrF) laser flash photolysis. The transient absorption spectra and kinetics obtained from the interaction of 3MQ* with polyG demonstrated that the primary radical ion pair, radical cation of polyG and radical anion of menadione can be detected simultaneously. The results demonstrated that the reaction rate constant of 3MQ* with polyG is almost equal to that of 3MQ* with dGMP.