Synthesis,characterization, and cytotoxic in vitro studies of the antibiotic drug metronidazole complexed with Au(III), Fe(III), Pd(III), and Zn(II): Toward potent gold-drug nanoparticles in cancer chemotherapy

Prolifiration of cancer incidents over recent decades has motivated researchers to explore new metal complexes with potential anticancer properties as alternative chemotherapeutic agents in clinical treatments. Au³⁺, Fe³⁺, Pd³⁺, and Zn²⁺ complexes of the drug metronidazole (MZ) were synthesized and characterized in the current study by elemental analysis, magnetic moment, molar conductance, UV–Vis, IR, Raman, and ¹H NMR spectroscopy. Morphology and nanometry of the complexes have been studied by XRD, SEM, and TEM techniques. In vitro cytotoxicity of the Au(III) complex against two human tumor cell lines was assessed by the MTT method. The Au(III) complex formed well-organized nanoparticles with the main diameter in the range of 6–34 nm. It exhibited the significant cytotoxic effect against human hepatocellular carcinoma cells with potency caю 7.5 times greater than that of free MZ.