Investigation of Interactions between Cationic and Anionic Porphyrins and BSA in Aqueous Media

摘要

In the present work interaction of the cationic and anionic porphyrins with bovine serum albumin in aqueous solutions with different pH has been studied. For strongly associated porphyrin study was conducted in a mixed solvent containing 0.19 M DMF, which shifted the associative equilibrium towards monomerization. It was found that the complexation of porphyrins with protein is possible due to p - p interaction between aromatic amino acid residues and p-system of porphyrin, hydrogen bonds between the peripheral substituents of porphyrins with amino acid residues of the protein, and in the case of sodium salt of 5,10,15,20-tetrakis (4-carboxymethylenoxyphenyl) porphyrin, ammonium salt of 5,10,15,20-tetrakis (4-sulfophenyl) porphyrin and 5,10,15,20-tetrakis (4-N-methylpyridyl) porphyrin tetra iodide interaction of amino acid residues of the protein to the reaction center of the porphyrin. It was determined that the complexation constants of studied porphyrins with protein are depends on the nature of the porphyrins peripheral substitution and does not depend on pH.