Aluminium oxide nanoparticles inhibit EPS production, adhesion and biofilm formation by multidrug resistant...

Area of Science:

• Nanotechnology
• Microbiology
• Materials Science

Background:

• Acinetobacter baumannii is a multidrug-resistant pathogen causing respiratory infections.
• Biofilm formation is a key virulence factor for A. baumannii.

Purpose of the Study:

• To synthesize and characterize aluminium oxide nanoparticles (Al2O3 NPs).
• To evaluate the efficacy of Al2O3 NPs against multidrug-resistant A. baumannii, focusing on biofilm inhibition.
• To assess the safety profile of Al2O3 NPs.

Main Methods:

• Synthesis and characterization of Al2O3 NPs using TEM and EDX.
• Determination of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC).
• Assessment of Al2O3 NPs' effect on bacterial membrane integrity, biofilm formation, bacterial adhesion, and extracellular polymeric substance (EPS) production.
• Cytotoxicity evaluation in HeLa cell lines.

Main Results:

• Spherical Al2O3 NPs with a diameter < 10 nm were synthesized.
• Al2O3 NPs demonstrated significant inhibition of biofilm formation (11.64–70.2%) and reduced bacterial attachment (48.8–51.9%).
• NPs reduced EPS production and the biomass of established biofilms, with no observed toxicity in HeLa cells at concentrations up to 120 µg/mL.

Conclusions:

• Al2O3 NPs are effective against multidrug-resistant A. baumannii by targeting key virulence factors like biofilm formation and adhesion.
• The synthesized Al2O3 NPs exhibit a favorable safety profile, suggesting their potential for therapeutic applications.
• These findings highlight Al2O3 NPs as a promising strategy to combat challenging bacterial infections.