Nanoengineered γ MnO2 Accelerates the Degradation of Antibiotic-Resistant Biofilms

TL;DR

This paper introduces nanoengineered MnO2 particles that effectively destroy antibiotic-resistant bacterial biofilms while being safe for human cells.

Contribution

The study introduces MnO2 nanoparticles with autonomous navigation and redox-driven mechanisms to combat antibiotic-resistant biofilms.

Findings

MnO2 nanoparticles achieved >98% eradication of MRSA and MDR E. coli biofilms.

The nanoparticles disrupted both EPS and cell membranes without losing structural integrity.

MnO2 showed ≥85% cell viability in human fibroblasts and keratinocytes at therapeutic concentrations.

Abstract

Bacterial biofilms remain a major challenge in clinical infections due to their dense extracellular polymeric substance (EPS) matrix and strong resistance to conventional antibiotics. This study reports manganese dioxide (MnO2) nanoparticles capable of autonomous navigation toward bacterial clusters, mechanical penetration of biofilm structures, redox-driven membrane disruption, and synergistic oxidative stress. The nanoparticles exhibit directional movement attributed to a combination of negatively charged surface potential, asymmetric topology, and catalytic reactivity toward bacterial metabolites. MnO2 demonstrates potent antibiofilm activity against MRSA and MDR E. coli (>98% eradication) and partial activity against Pseudomonas aeruginosa. Time-lapse microscopy, EPR spectroscopy, XPS analysis, and SEM imaging reveal that MnO2 disrupts both EPS and cell membranes while maintaining structural integrity throughout treatment. Cytotoxicity assays confirm ≥85% viability in human fibroblasts and keratinocytes at therapeutic concentrations. MnO2 shows controlled biodegradation into Mn2+ ions, which participate in physiological pathways and undergo renal clearance. These findings support MnO2 nanoparticles as promising biofilm-targeting agents for topical formulations, wound care, and implant coatings.

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