The DNA- and protein-binding properties and cytotoxicity of a new copper(II) hydrazone Schiff base complex

A new monomeric copper(II) benzhydrazone complex, [Cu(L)(H2O)(NO3)] (1), has been synthesized using Schiff base derived from quinoline-2-carboxaldehyde and benzhydrazide. Complex 1 was characterized by elemental analysis, FT-IR, UV-Vis spectroscopy along with electrochemical study and single-crystal X-ray crystallography. Single-crystal diffraction study of 1 indicates that the copper(II) ion adopts a distorted square pyramidal (SQP) geometry. The calf-thymus (CT) DNA-binding property of 1 has been evaluated by employing UV-vis and fluorescence spectroscopy, cyclic voltammetry and viscosity studies. The protein-binding ability of 1 was investigated by UV-vis and fluorescence spectroscopy titration using BSA and HSA. The significant interaction of 1 with CT-DNA was further supported by molecular docking approach. Finally, in vitro cytotoxicity of 1 was investigated by MTT assay on the Human Skin Carcinoma cell line A431. All these facts indicate that 1 exhibits a promising anticancer activity.