Synthesis, characterization, antioxidant, antibacterial activity, and molecular docking studies of Zn (II) and Cu (II) complexes nanoparticles

This study involved the synthesis and characterization of a new Schiff base ligand, prepared by reacting 3-nitrobenzaldehyde with thiourea in ethanol as the reaction medium. Complexes derived from this ligand were then prepared by coupling it with metal ions such as Copper (II) and Zinc (II). Zn and Cu nanoparticles were synthesized using pulsed laser irradiation. The prepared complexes were characterized through melting point determination, molar conductivity, elemental analysis (CHN), IR, UV-Vis, 1H NMR, 13C-NMR, and mass spectrometry. Bactericidal tests indicated that both the Copper and Zinc complexes exhibited significantly higher bactericidal activity against the tested strains than the ligand alone, showing greater antibacterial efficacy than the parent ligand. Docking studies demonstrated reasonable binding affinity with a bonding energy of -8.5 kcal/ mol, sufficient to inhibit crucial proteins related to bacterial growth and reproduction. The anticancer activity of ZnO NPs, CuO NPs, and doxorubicin was evaluated by determining the cell viability of MCF-7, SW620, and A549 human cells using MTT assays. In the experiment, CuO NPs exhibited the highest cytotoxic effect, surpassing that of ZnO NPs and even showing greater anticancer efficacy than doxorubicin. These findings support ongoing research into Schiff base metal complexes and metal oxide NPs, especially regarding their potential applications in new therapeutic areas, such as antibacterial agents and cancer treatment. Additionally, the study demonstrated that ZnO nanoparticles efficiently degrade Malachite Green dye under UV light, achieving 97 % degradation efficiency at 40 degrees C. Higher temperatures increased degradation rates, indicating that the process is endothermic and more favorable at elevated temperatures.