Green-synthesized Mg-doped CuO nanoparticles targeting septicemia pathogens: Enhanced antibacterial and cancer cell cytotoxicity.

Copper oxide (CuO) and Mg-doped CuO (CuO-Mg) nanoparticles were synthesized using a green approach with Azadirachta indica leaf extract. The biosynthesized nanoparticles were characterized using multiple techniques including x-ray diffraction (XRD), energy-dispersive x-ray (EDX) analysis, scanning electron microscopy (SEM), and UV-Vis-NIR spectrometry. The XRD analysis verified the purity of the synthesized materials and confirmed a monoclinic crystal structure. Doping CuO with Mg decreased the average crystallite size. EDX spectral analysis confirmed the presence of Cu, Mg, and O elements in the Mg-doped nanoparticles. The optical bandgap ranged from 1.28 to 1.37 eV, in which undoped CuO exhibited a high optical bandgap. The antibacterial activity of CuO nanoparticles increased upon increasing the concentration of Mg doping against the tested pathogens, including Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, and Staphylococcus aureus. The biosynthesized CuO and Mg-doped CuO nanoparticles demonstrated potent concentration-dependent cytotoxic effects on breast cancer cells, achieving complete growth inhibition at 70 μg/ml CuO and 60 μg/ml Mg-doped CuO, with IC50 values of approximately 35.4 and 30.0 μg/ml, respectively.