Antimicrobial resistance is a constant concern to public health around the world. Antimicrobial materials have been put into wound dressings and medical equipment such as implants and catheters to resist the spread of dangerous microorganisms. Because of their low minimum inhibitory concentrations (MICs) against common Gram-negative pathogenic bacteria like P. aeruginosa, Ag-salts and Ag-nanoparticles (AgNPs) are the most commonly used of these materials. However, such Ag-based materials are only effective against Gram-negative bacteria and are prone to producing Ag-resistant phenotypes after only 7 successive sub-inhibitory exposures. Some bismuth compounds have been used for centuries to treat a range of microbiological illnesses, including syphilis, diarrhea, gastritis, and colitis, due to their low toxicity and high efficacy. All Bi-based NPS, according to the literature, results in relatively large-sized NPs. In most of the antimicrobial activity studies, Bi-based NPs have been prepared by the traditional bottom-up method that requires the use of a soluble bismuth salt to react with a base in the controlled nucleation of Bi-based NPs. Using a top-down synthetic approach and ultrasound energy, we were able to successfully synthesize fine-sized and well-established Bi-based NPS, such as Bi2O3 NPS. We show that Bi2O3 NPs may kill both Gram-negative (MIC = 0.75 g/mL vs. P. aeruginosa) and Gram-positive (MIC = 2.5 g/mL vs. S. aureus) bacteria, as well as Ag-resistant and carbapenem-resistant bacteria (MICs = 1.0 g/mL and 1.25 g/mL, respectively), and that they can sensitize bacteria towards meropenem. Unlike previous metal antimicrobial technologies, Bi2O3 NPs do not contribute to the formation of antimicrobial-resistant phenotypes, with no resistance detected after 30 passes. We hope that this study will lead to more research into the use of various metal oxides as antimicrobial materials, especially those that limit the development of resistance phenotypes.

Bi2O3 nanoparticles exhibit potent broad-spectrum antimicrobial activity and the ability to overcome Ag-, ciprofloxacin- and meropenem-resistance in P. aeruginosa

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.