Synthesis, characterization, DNA interaction, cytotoxicity, and apoptosis induction of a mixed-ligand copper(II) complex

摘要

A mixed-ligand complex, [Cu(Hptc)(Me_2bpy)(H_2O)]-3H_2O (1) (H_3ptc = pyridine-2,4,6-tricarboxylic acid; Me_2bpy = 4,4'-dimethyl-2,2'-dipyridine), has been synthesized and characterized by elemental analysis, 1R, and single-crystal X-ray diffraction. In the discrete mononuclear structure of 1, the copper core is in a distorted octahedral environment (CuN_3O_3) derived from tridentate chelate Hptc~(2-), bidentate chelate Me_2bpy and a coordinated water. The interaction of 1 with CT-DNA was investigated by UV-vis spectra, fluorescence spectra and viscosity, which reveals that 1 binds to CT-DNA by partial intercalation. Gel electrophoresis assay demonstrated that the complex displays efficient oxidative cleavage of supercoiled DNA with H_2O_2 as an oxidant. The in vitro cytotoxicity of 1 on HeLa cells was assessed by MTT and clonogenic assay, where IC_(50) equals 4.24 ± 0.03 uM. Fluorescence microscopic observations indicated that 1 can induce apoptosis of HeLa cells.