Yury A. Gubarev

Spectral and hydrodynamic studies of complex formation of tetraalkoxy substituted zinc(II)phthalocyanines with defatted and nondefatted bovine serum albumin

Spectral, hydrodynamic and thermochemical studies have been demonstrated that tetraalkoxy substituted zinc(II)phthalocyanines form stable complexes with defatted and nondefatted bovine serum albumin. The phthalocyanines interact with BSA through heteroatoms of their peripheral substitutes. It was found that ZnPc(4-NH-CO-C6H4-OC3H7)4 is located in the protein subdomains IB and IIA whereas ZnPc(4-NHCO-C6H4-OC6H13)4 and ZnPc(4-NH-CO-C6H4-OC8H17)4 are immobilized on surface of the protein globule at a distance of not greater than 10 nm from the tryptophan residues in the positions 135 and 214 of the protein polypeptide chain. Zinc(II)phthalocyanines (ZnPc(4-NH-CO-C6H4-OC6H13)4 and ZnPc(4-NH-CO-C6H4-OC8H17)4) increase thermal stability of BSA.

The interaction of cationic and anionic porphyrins with the bovine serum albumin in borate buffer

The interaction of water-soluble porphyrins with the bovine serum albumin in borate buffer at pH 8.6 has been studied. The localization of porphyrins in the protein globule has been determined. It was established that the native conformation of albumin upon binding with the porphyrins is preserved, however, the anionic porphyrins are exhibit wedging effect on the albumin domains. The binding constants were obtained from fluorescence spectroscopy data.

A new strategy for targeted delivery of non-water-soluble porphyrins in chitosan-albumin capsules

AbstractThis study was focused on obtaining polymer complex of 5-(4′-N-tert-butyloxycarbonylglicinaminophenyl)-10,15,20-triphenylporphine and 5-(4′-amonophenyl)-10,15,20-triphenylporphine with chitosan. The polymer complexes were characterized spectrally and calorimetrically. The existence of a substituent capable of forming hydrogenic complexes with proteins and other biopolymers in porphyrins provides an effective immobilization of a photosensitizer. Binding with porphyrins was found to result in twisting the chitosan globule and encapsulation of porphyrins. Coating of polymer complex with bovine serum albumin promotes neutralization of zeta potential and formation of 180-nm capsules. As the result of the study, a new universal strategy of water insoluble preparation encapsulation in biopolymers for targeted delivery of drugs and their further release was suggested. Graphical abstractᅟ

Thermodynamic aspects of interaction zinc(II)tetraphenylporphyrin with bidentate ligands in dilute solutions

Molecular complex formation of zinc(II)tetraphenylporphyrin with the ligands—diamino compounds in toluene was studied using calorimetric and spectroscopy titration. The structure of the complexes has been confirmed using 1H NMR and fluorescence spectroscopy. Nature of the interaction between the ligand and the solvent was established using TGA of solvates.