Репозиторий Университета

© 2019, Pleiades Publishing, Ltd. Abstract: It is shown that the efficacy of the photosensitized oxidation of organic substrates in aqueous media (with the oxidation of tryptophan being used as an example) does not depend on adding biologically active dinitrosyl iron complexes (DNICs) with thiol-containing ligands to the reaction medium if it contains Pluronic F127, a poly(ethylene oxide)–poly(propylene oxide)– poly(ethylene oxide) triblock copolymer, at concentrations higher than the critical micelle concentration. Photosensitizer molecules are localized in Pluronic micelles and are shielded from the damaging impact of NO• radicals that form upon the photodegradation of DNIC molecules. Photodynamic therapy (PDT) sessions (the photoinduced necrosis and apoptosis of cells in pathologically altered tissues and the simultaneous initiation of regeneration and repair of the treated tissues due to the photodecomposition of DNIC molecules) thus become fundamentally possible.

© 2018, Pleiades Publishing, Ltd. Abstract: Mono- and diethylene oxide derivatives of tetra(p-hydroxyphenyl)porphyrin (THPP) with different conformation states are synthesized. These compounds exhibit high photosensitization activity in the generation of singlet oxygen in organic and aqueous (in the solubilized state) phases. It is shown that introducing ethylene oxide moieties into the hydroxyphenyl substituents of THPP increases its solubility in chloroform. In addition, the activity of singlet oxygen 1Δg generation in the reaction of anthracene photooxidation by THPP tetra derivatives in chloroform, where the ethylene oxide fragments are introduced into two phenyl rings and hexadecyl fragments are introduced into another two, is higher than the activity of mono- and di-modified THPP molecules with enthylene oxide molecules at one hydroxyphenyl cycle. The activity of tetra-substituted porphyrin in chloroform, however, is comparable to that of nonsubstituted tetraphenylporphyrin, considered to be one of the most active photosensitizers. The produced ethylene oxide derivatives of THPP are solubilized with pluronic F-127 (triblock copolymer of ethylene- and propylene-oxides)—one of the least toxic and effective polymeric detergents—forming water-soluble forms of the respective porphyrins. It is established that the pluronic solubilization capability (the lowest molar concentration of pluronic required for the complete transfer of porphyrin of a particular molar concentration dissolved in organic phase to the water-soluble form) is higher for asymmetrical mono- and di-derivatives of the THPP than for symmetric tetra-substituted THPP. It is shown that the activity of the solubilized water-soluble form of mono- and tetra-derivatives in tryptophan photoxidation is higher than that of unsubstituted THPP and is comparable to the activity of tetraphenylporphyrin.