Vol. 13, Issue 1 (2025)

The rise of antibiotic-resistant bacteria, including Escherichia coli (E. coli) and Diplococcus pneumoniae (D. pneumoniae), poses a critical threat to global public health. Nanotechnology offers a promising solution, with metal oxide nanoparticles showing potent antimicrobial properties. This study focuses on the synthesis, characterization, and optimization of cobalt oxide (CoO) and magnesium oxide (MgO) nanoparticles for antimicrobial applications. CoO and MgO nanoparticles were synthesized using the sol-gel method and optimized for size, morphology, and surface properties.

Characterization techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), and zeta potential analysis were employed. The particle size analysis (PSA) revealed an average size of 32 nm for CoO and 45 nm for MgO nanoparticles. Zeta potential measurements indicated surface charges of −32.6 mV for CoO and −25.4 mV for MgO, ensuring nanoparticle stability and efficient interaction with bacterial membranes. The antibacterial efficacy of these nanoparticles was evaluated against E. coli and D. pneumoniae using minimum inhibitory concentration (MIC) and zone of inhibition assays. The results demonstrated that both CoO and MgO nanoparticles exhibit strong antibacterial activity, with CoO showing higher potency against E. coli and MgO being more effective against D. pneumoniae. This study provides evidence that optimized CoO and MgO nanoparticles can serve as potent antimicrobial agents, with potential applications in medical treatments and infection control. Further research is recommended to explore their mechanisms of action and potential toxicity in biological systems.