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Surfactant-assisted self-assembly of porphyrin molecules in aqueous solutions sometimes leads to the formation of hybrid supramolecular structures with unusual photophysical properties resulting from the dipole–dipole interactions between the neighboring aromatic systems. The macrocycle orientation and interchromophore distance in such assemblies are determined by the dye–surfactant interactions, and hence, strongly depend on the molecular structure of both surfactant and porphyrin molecules. In this paper we studied the influence of the number and position of the peripheral alkyl chains of amphiphilic meso-aryl-substituted porphyrins on their aggregation behavior and intermolecular interactions with different surfactants in aqueous solutions. The studies revealed a crucial role of the local acidity on the micellar surface in the protolytic equilibrium of the porphyrin derivatives, as well as the influence of the macrocycle hydrophilic–lipophilic balance on its solubilization site within a micellar system. These findings enable prediction of the photophysical properties of amphiphilic porphyrin derivatives in the presence of different solubilizing agents and membrane-mimetic systems, and hence, selection the most suitable drug delivery systems for the novel amphiphilic porphyrin-based photosensitizers.

This work is devoted to the search for new antiherpes simplex virus type 1 (HSV-1) drugs among synthetic tetrapyrroles and to an investigation of their antiviral properties under nonphotodynamic conditions. In this study, novel amphiphilic 5,10,15,20-tetrakis(4-(3-pyridyl-n-propanoyl)oxyphenyl)porphyrin tetrabromide (3a), 5,10,15,20-tetrakis(4-(6-pyridyl-n-hexanoyl)oxyphenyl)porphyrin tetrabromide (3b) and known 5,10,15,20-tetrakis(1-methyl-4-pyridinio)porphyrin tetraiodide (TMePyP) were synthesized, and their dark antiviral activity in vitro against HSV-1 was studied. The influence of porphyrin’s nanosized delivery vehicles based on Pluronic F127 on anti-HSV-1 activity was estimated. All the received compounds 3a, 3b and TMePyP showed virucidal efficiency and had an effect on viral replication stages. The new compound 3b showed the highest antiviral activity, close to 100%, with the lowest concentration, while the maximum TMePyP activity was observed with a high concentration, porphyrin 3a was the least active. The inclusion of the synthesized compounds in Pluronic F-127 polymeric micelles had a noticeable effect on antiviral activity only at higher porphyrin concentrations. Action of the received compounds differs by influence on the early or later reproduction stages. While 3a and TMePyP acted on all stages of the viral replication cycle, porphyrin 3b inhibited viral replication during the early stages of infection. The resulting compounds are promising for the development of utilitarian antiviral agents and, possibly, medical antiviral drugs.

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.

New amphiphilic conjugates of porphyrins and cyanine dye Cy5COOH were prepared by the creation of ester or amide bond between Cy5-carboxylic acid and hydroxy- or amino-substituted porphyrins. Study of self-aggregation of these conjugates in aqueous-organic media by dynamic light scattering and UV-VIS spectroscopy showed that the conjugates form micelles in THF–H2O with different ratios.

In this study, the series of A3B-type zinc porphyrin dyes have been synthesized for dye-sensitized solar cells (DSSC). All the received zinc-porphyrin complexes bear different alkyl substituents (none, tert-butyl-, methoxy-, hexyloxy-, dodecyloxy-, a pair of hexyloxy-), bulky electron-donating substituent (diphenylamino) in each of three meso-phenyl rings and carboxylic acid as acceptor/anchoring group. The influence of the number and length of alkyl chains on the photophysical properties and DSSCs photovoltaic performance was investigated, as well as quantum-chemical modeling was carried out. Our results reveal that the alkyl chains length and number affect cell performance. We found that DSSC power conversion efficiency increases with an increase in the length and number of alkyl substituents in the porphyrins. A maximum efficiency of 1.29 % was observed in solar cells with dodecyloxy-substituted zinc porphyrin.

In this work we report on the synthesis of new cationic pyridyl-containing meso-arylporphyrins and their antimicrobial photodynamic activity against Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria in planktonic and biofilm modes of growth. Received compounds were characterized by EAS, fluorescence, 1H, 13C NMR spectroscopy, liquid chromatography and ESI-MS spectra. Their photophysical (absorbance and fluorescence), photochemical (singlet oxygen generation) properties dark and light-induced toxicity were studied. Aggregation behavior of PSs was investigated in the presence of nonionic solubilizers to identify the most effective nanocarrier. Pluronic F-127 polymer micelles appeared the most suitable nanocontainers for the cationic porphyrins solubilization. The structure/biological activity relationships were evaluated. The influence of aliphatic spacer length on the photochemical and biological properties of tetraphenylporphyrin derivatives was estimated. The inclusion of PSs in polymeric micelles of Pluronic F-127 noticeably increased their photodynamic activity. Our research showed that the proposed porphyrin macrocycle design offers strategies for the efficient photosensitizer modification in the field of antimicrobial photodynamic inactivation.

The spectroluminescent properties of the noncovalent assemblies of CdSe semiconductor quantum dots with 5-(4-pyridyl)-10,15,20-tris(4-n-octaoxyphenyl)porphyrin and the efficiency of energy transfer from the quantum dots to the porphyrin molecule by the Forster resonant energy transfer mechanism were evaluated.