Synthesis and antimicrobial activity of iron oxide/silver nanocomposites against Pseudomonas aeruginosa biofilms

Pseudomonas aeruginosa are known for their pathogenicity, antimicrobial resistance, and ability to grow in biofilms, making them even more problematic in health care. In this context, nanotechnology allows the development of new materials against multiresistant microorganisms. The present study prepared colloidal dispersions of iron oxide (IONPs) and silver (AgNPs) nanoparticles and iron oxide/silver composite (IO/Ag-NC), testing them for toxicity and activity against biofilms of P. aeruginosa clinical isolates. Heterodimer nanocomposites showed spherical morphology and zeta potential, indicating relative colloidal stability despite their polydispersity. The nanoparticles did not present toxicity to Artemia salina at the tested concentrations and inhibited the biofilm formation of some P. aeruginosa clinical isolates. Nanoparticles (NPs) inhibited the biofilm formation of some P. aeruginosa clinical isolates: AgNPs inhibited biofilm formation in three isolates, IONPs reduced it in four, and IO/Ag-NCs inhibited it in three P. aeruginosa isolates. Further research should focus on strategies that consider increasing silver concentration and using IO/Ag-NCs as nanocarriers for controlling microbial biofilm formation.