Innovative hafnium composite: efficient fabrication and advanced biomedical potential in dentistry and oral health

The development of multifunctional dental coatings capable of preventing biofilm formation and promoting oral tissue health is a growing focus in modern restorative dentistry. In this study, a novel hafnium-based metal-organic framework was synthesized via a rapid microwave-assisted method using 4-aminopyridine-2,6-dicarboxylic acid as the organic linker. The synthesized MOF was abbreviated as Hf/APDC-MOF, derived from the names of its components (hafnium 4-aminopyridine-2,6-dicarboxylic acid metal-organic framework). The synthesized MOF was designed for potential use as a bioactive dental surface coating with broad-spectrum therapeutic functions. The material demonstrated strong antibacterial activity against key oral pathogens, including Streptococcus mutans and Porphyromonas gingivalis, with minimum inhibitory concentration (MIC) values of 1 μg mL^-1. In vitro cytotoxicity testing using the MTT assay revealed selective anticancer effects against SCC154 (CRL-3241) gingival carcinoma cells, with an IC₅₀ value of 78 μg mL^-1. Additionally, the MOF exhibited high antioxidant capacity (79% DPPH radical scavenging at 100 μg mL^-1) and effective anti-inflammatory activity by reducing nitric oxide production by 74% in LPS-stimulated RAW 264.7 macrophages. These results suggest that Hf/APDC-MOF is a promising candidate for multifunctional dental coatings, combining antimicrobial protection with antioxidant, anti-inflammatory, and anticancer effects, thereby offering a novel therapeutic platform for oral health management. The synthesized MOF was designed and evaluated in vitro as a multifunctional bioactive material with potential relevance to dental surface coatings, combining antimicrobial, antioxidant, anti-inflammatory, and anticancer properties.