Unveiling the Antibacterial Efficacy and Mechanistic Insights of MnO₂ Nanoparticles for Advanced Therapeutic...

Pathogenic bacterial infections pose serious health risks, underscoring the need for timely treatments. Manganese dioxide (MnO₂) nanoparticles (NPs) have attracted considerable attention owing to their outstanding chemical stability, favorable biocompatibility, high reactivity, and catalytic ability to decompose hydrogen peroxide, making them promising antibacterial agents. A clear understanding of their antibacterial mechanisms is essential for evaluating their therapeutic potential in clinical settings. In this study, MnO₂ NPs were synthesized by reacting potassium permanganate (KMnO₄) with poly(allylamine hydrochloride) (PAH), ensuring complete conversion to MnO₂ NPs. The resulting NPs were characterized for their physicochemical properties, and their antibacterial activity against E. coli and S. aureus was evaluated using growth curve assays and reactive oxygen species (ROS) quantification. Results indicated the killing efficiency of MnO₂ NPs increased with exposure time and concentration, reflecting high susceptibility of both bacterial strains. Scanning electron microscopy (SEM) analysis revealed that the interaction between MnO₂ NPs and bacterial cells caused significant disruption of cell wall integrity. This study provides a valuable platform for evaluating MnO₂ nanoparticles as antibacterial agents and for exploring their mechanisms in medical applications.