title: Interaction of two new mixed ligand copper(II) complexes with DNA probed by thermodynamic and spectroscopic studies.
abstract: The DNA binding behavior of [Cu(4,7-dmp)(phen-dione)Cl]Cl (1) and [Cu(2,9-dmp)(phen-dione)Cl]Cl (2) where dmp and phen-dion stand for dimethyl-1,10-phenanthroline and 1,10-phenanthroline-5,6-dion, respectively, was studied with a series of techniques including Viscometry, UV-Vis absorption, circular dichroism and fluorescence spectroscopy. Cytotoxicity effect was also investigated. Thermodynamic parameters, enthalpy and entropy changes were calculated according to Van't Hoff equation, which indicated that both reactions are predominantly enthalpically driven. However, these two complexes show different behavior in fluorescence, circular dichroism and viscometry methods which indicate the Cu(II) complexes interact with calf-thymus DNA by different mode of binding. These have further been verified by competition studies using Hoechst as a distinct groove binder. All these results indicate that these two complexes (1) and (2) interact with CT-DNA via groove binding and partially intercalative mode, respectively and the binding affinity of the complex 1 is higher than that of complex 2. Finally, our findings suggest that the type of ligands and structure of complexes have marked effect on the binding affinity of complexes involving CT-DNA. Also, these new complexes showed excellent antitumor activity against human T lymphocyte carcinoma-Jurkat cell line.
authors.affiliation: Faculty of Chemistry, Sensor and Biosensor Research Center (SBRC) & Nanoscience and Nanotechnology Research Center (NNRC), Razi University, 67149, Kermanshah, Iran, kashanian_s@yahoo.com.
authors.forename: Soheila
authors.initials: S
authors.lastname: Kashanian
authors.forename: Mohammad Mehdi
authors.initials: MM
authors.lastname: Khodaei
authors.forename: Hamideh
authors.initials: H
authors.lastname: Roshanfekr
authors.forename: Ghobad
authors.initials: G
authors.lastname: Mansouri
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry* / Q000494:pharmacology; D001667:Binding, Competitive; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D056831:Coordination Complexes / Q000737:chemistry* / Q000494:pharmacology; D004247:DNA / Q000737:chemistry*; D004277:DNA, Single-Stranded / Q000737:chemistry; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D020128:Inhibitory Concentration 50; D007364:Intercalating Agents / Q000737:chemistry*; D019169:Jurkat Cells; D010618:Phenanthrolines / Q000737:chemistry* / Q000494:pharmacology; D013816:Thermodynamics; D017186:Titrimetry; D014783:Viscosity
chemical_list: D000970:Antineoplastic Agents; D056831:Coordination Complexes; D004277:DNA, Single-Stranded; D007364:Intercalating Agents; D010618:Phenanthrolines; D004247:DNA; C427203:calf thymus DNA