Improved antibacterial and antibiofilm activity of magnesium fluoride nanoparticles obtained by water-based ultrasound chemistry

Antibiotic resistance has prompted the search for new agents that can inhibit bacterial growth. We recently reported on the antimicrobial and antibiofilm activities of nanosized magnesium fluoride (MgF₂) nanoparticles (NPs) synthesized in ionic liquid using microwave chemistry. In this article, we describe a novel water-based synthesis of MgF₂ NPs using sonochemistry. The sonochemical irradiation of an aqueous solution of [Mg(OAc)₂{dot operator}(H₂O)₄] containing acidic HF as the fluorine ion source afforded crystalline well-shaped spherical MgF₂ NPs that showed much improved antibacterial properties against two common bacterial pathogens (Escherichia coli and Staphylococcus aureus). We were also able to demonstrate that the antimicrobial activity was dependent on the size of the NPs. In addition, using the described sonochemical process, we coated glass surfaces and demonstrated inhibition of bacterial colonization for 7 days. Finally, the antimicrobial activity of MgF₂ NPs against established biofilms was also examined. Taken together our results highlight the potential to further develop the concept of utilizing these metal fluoride NPs as novel antimicrobial and antibiofilm agents. From the Clinical Editor: In this article, the authors describe a novel aqueous synthesis of magnesium fluoride NPs using sonochemistry. These nanoparticles have improved antibacterial and antibiofilm activity compared to their counterparts with traditional synthesis methods.