Screening of antibacterial and cytotoxicity of the copper (II) complexes of N-donor chelating ligand

Abstract

Copper (II) complexes, namely dichloromono(1-amidino-O-ethylurea)copper (II), (1) and bis(1-amidino-O-ethylurea)copper (II) bromide, (2) were synthesized and characterized. The antibacterial screening of complexes 1 and 2 was performed along with their corresponding metal salts (CuCl2.2H2O) and (CuBr2), and ligand (dicyandiamide), against two human urinary pathogenic bacterial strains, Escherichia coli and Proteus mirabilis, by the disc diffusion method. All test compounds, except ligand have shown significant antibacterial activities on both bacterial strains. Their antibacterial effectiveness increased in a dose dependent manner, whereas their ability to inhibit the growth of both bacterial species decreased as their incubation time increased. The activity of complex 1 was found to be greater than its metal salt, while that of complex 2 was lower than the corresponding metal salt on both bacterial species. The in-vitro cytotoxic screening of complexes 1 and 2 was also assessed against human cervical adenocarcinoma cancer (HeLa) cell line using the MTT assay. Both complexes 1 and 2 have displayed cytotoxic effect in a dose-dependent manner with IC50 values of 59.64±6.68 µg/mL and 62.85±0.39 µg/mL, respectively. Overall, the highest antibacterial and cytotoxic activity of the present work is provided by complex 1.