Electrochemical investigation and DNA-binding studies of pefloxacin-metal(II/III) complexes

Complexes of pefloxacin (PEF), with Cu(II), Zn(II), Pt(II), Ru(III), and Fe(III) have been synthesized and characterized by spectroscopic techniques involving UV-Vis, IR, H-1-HMR, CHN elemental analysis, electrochemical, and thermal behaviors. The electrochemical properties of all complexes were investigated by cyclic voltammetry (CV) using a glassy carbon electrode. The biological activities of the complexes have been evaluated by examining their ability to bind to calf thymus DNA (CT-DNA) with UV spectroscopy and CV. UV studies of the interaction of the complexes with DNA show that these compounds can bind to CT-DNA and the binding constants have been calculated. The cyclic voltammograms of the complexes in the presence of CT-DNA show that the complexes can bind to CT-DNA by intercalative and electrostatic binding. The antimicrobial activities of these complexes have been evaluated against three Gram-positive and four Gram-negative bacteria. Antifungal activities against two different fungi have been evaluated and compared with pefloxacin as reference. Almost all complexes show excellent activity against all bacteria and fungi.