Cytotoxic, antibacterial, DNA interaction and superoxide dismutase like activities of sparfloxacin drug based copper(II) complexes with nitrogen donor ligands

The novel neutral mononuclear copper(II) complexes with fluoroquinolone antibacterial drug, sparfloxacin and nitrogen donor heterocyclic ligand have been synthesized and characterized. An antimicrobial efficiency of the complexes has been tested against five different microorganisms and showed diverse biological activity. The interaction of complex with Herring sperm (HS) DNA was investigated using viscosity titration and absorption titration techniques. The results indicate that the complexes bind to DNA by intercalative mode and have rather high DNA-binding constants. DNA cleavage study showed better cleaving ability of the complexes compare to metal salt and standard drug. All the complexes showed good cytotoxic activity with LC50 values ranging from 4.89 to 11.94 μg mL−1. Complexes also exhibit SOD-like activity with their IC50 values ranging from 0.717 to 1.848 μM.

Electronic absorption spectroscopy is universally employed to examine the binding mode of DNA with the metal complex..Figure optionsDownload as PowerPoint slideHighlights
► Drug based mixed-ligand Cu(II) complexes have been synthesized and characterized.
► Antibacterial activity of complexes against Gram(+ve) and Gram(−ve) bacteria has been checked.
► DNA interaction studies have been carried out using different techniques.
► Superoxide dismutase activity has been done to measure the IC50 value of the complexes.
► Cytotoxicity of the complexes has been performed to measure the LC50 values.