Synthesis, characterization and in vitro biological assays of copper(II) and nickel(II) complexes with furan-2-carboxylic acid hydrazide

Two transition metal complexes, [Cu(FH)(3)]2Cl2H(2)O and [Ni(FH)(3)]2Cl2H(2)O, were synthesized from the reactions of furan-2-carboxylic acid hydrazide with CuCl(2)2H(2)O and NiCl(2)6H(2)O. The synthesized complexes were characterized using analytical and various spectral techniques. The structures of the complexes were determined using single-crystal X-ray diffraction. The interactions of the complexes with calf thymus DNA (CT-DNA) were studied using absorption, fluorescence, cyclic voltammetric and viscosity measurements. The experimental results showed that the complexes could interact with CT-DNA through intercalation. A gel electrophoresis assay demonstrated the ability of the complexes to cleave pBR322 DNA. The binding interaction of the complexes with bovine serum albumin was investigated using a fluorescence spectroscopic method. The radical scavenging ability, assessed using a series of antioxidant assays involving 2,2-diphenyl-2-picrylhydrazyl radical, hydroxyl radical and nitric oxide radical, showed that the complexes possess significant radical scavenging properties. Further, the in vitro cytotoxic effect of the complexes examined on cancerous cell lines, such as human cervical cancer cells (HeLa) and human breast cancer cell line (MCF-7), showed that the complexes exhibit significant anticancer activity.