COMPARISON OF METALLOPORPHYRINS INTERACTING WITH DNA

A series of metalloporphyrins (CuTMpyP, CuTMAP, CuTPPS, NiTMpyP, ZnTMp yP and CdTMpyP) reacting with DNA were compared. The interaction of me talloporphyrin with DNA shows different binding modes and electrochemi cal behavior when either the metal ion or porphyrin ligand is differen t. Due to electrostatical repulsion interaction between the anionic su bstitute group and a phosphate group on DNA molecular backbone, it is difficult for the anionic porphyrin to interact with DNA, The ability of cationic porphyrins to react with DNA depends on the size of the su bstitute group and the metal ion in the porphyrin plane center, Metall oporphyrin with or without axial ligand, which depends on the metal io n, results in outside binding or intercalating modes, and shows differ ent interaction capability with DNA, The conditional binding constants of NiTMpyP, CuTMpyP and CuTMAP, which mainly show intercalating mode to DNA, were evaluated.