Spectral and kinetic properties of intermediates induced by reaction of hydrated electrons with adenine, adenosine, adenylic acid and polyadenylic acid: a multicomponent analysis

The overlapping transient optical absorption spectra obtained from pulse radiolysis experiments in which the hydrated electron reacted with adenine, adenosine, 5'-adenosine monophosphate and polyadenylic acid were measured and analysed. The analysis consists of a multicomponent analysis which yields the number of different species and a set of orthonormal basis spectra. From this set of basis spectra together with a number of trial models for the possible kinetics of the different species the best model is determined by fitting the original data. In this way the molar absorptivity spectra and the kinetics of the species can be found. To describe all the spectra of the adenine-containing compounds in a consistent way we need, at most, three different species. The following reaction scheme is obtained: esub(aq)- + A → A- radical, A- radical + H2O ↔ A'H radical + OH-, A- radical → A''H radical and A'H radical (A''H radical) + A'H radical (A ''radical) The radicals A'H radical and A''H radical are both protonated electron adducts, while P appears to be stable product with a decay time of the order of 1 day. (author)