Antibacterial silver nanoparticle decorated gallium metal-organic frameworks for odontogenic infections.

Surgical debridement of infected oral tissues can compromise maxillofacial aesthetics and anatomical function, thereby reinforcing the use of antibiotics as a first-line therapy. However, the escalation of multidrug resistance has accelerated the search for non-antibiotic antimicrobial platforms. In this study, bactericidal hybrid gallium–silver metal-organic frameworks (MOFs) were synthesized by nucleating the formation of silver nanoparticles at the surface of gallium MOF scaffolds. Spectroscopy studies confirmed the elemental composition of silver-gallium MOF hybrids, while X-ray diffraction showed that the crystalline framework was retained after silver incorporation. Thermogravimetric analysis further indicated that silver incorporation increased thermal decomposition temperatures of the complex, and reduced total mass loss from ~ 57% to ~ 47%, indicating anchorage of silver nanoparticles at the gallium MOF surface stabilizes the carrier nanostructure. Antibacterial assays demonstrated gallium-silver MOFs significantly inhibit the growth of the model oral pathogens S. mitis and S. pneumoniae at a dose of ≥ 3.9 µg/mL, a concentration found to be tolerated by human cellular models, through contact-dependent membrane disruption. Therapeutic formulations were additionally effective in clearing microbial biofilms grown on tooth enamel-mimetic hydroxyapatite discs. These proof-of-concept findings suggest that gallium–silver hybrid MOFs hold promise as an attractive topical antimicrobial with potential to rapidly clear odontogenic infections.