Photonics of UO22+ complexes with tryptophane. 3. Photocatalyzed by UO22+ ions oxidation of tryptophan

Spectral-luminescent investigation of intracomplex tryptophan (Trp) oxidation photo catalyzed by UO22+ ions is carried out. Photo catalytic effect of uranyl ion is explained by stabilization of charge division in complex [UO2+...Trp+], that increases the possibility of electron transfer from uranoyl ion to oxygen with formation of superoxide-ion O2-, which in the case of its interaction with Trp+ ion-radical forms N-formylkynurenine and kynurenine. Using data of excitation and fluorescence spectra of Trp oxidation products it is concluded that formation of N-formylkynurenine and kynurenine takes place through intracomplex mechanism and these compounds keep in uranyl-ion coordination sphere