Antimicrobial and Antiviral Activities, and Biocompatibility of Titanium Coated with Electron Beam-Irradiated α-Silver Tungstate Microcrystals

The development of biomaterials with modified surfaces is a promising strategy to prevent microbial adhesion, biofilm formation, and viral contamination on implants. Alpha-silver tungstate (α-Ag₂WO₄) exhibits well-recognized antimicrobial activity, which can be further enhanced by electron beam irradiation (EBI). This study evaluated the antimicrobial, antiviral, and cytotoxic performance of titanium (Ti) discs coated with α-Ag₂WO₄, with or without EBI treatment, using the spin coating method. Material characterization revealed no significant differences in structure, composition, or morphology between the two coatings. Both coatings increased the surface roughness and surface free energy of the discs. Regarding antibiofilm effects, reductions of 3.46 and 3.31 log₁ ₀ CFU/mL were observed for <i>Streptococcus sanguinis</i> on irradiated and nonirradiated coated surfaces, respectively, whereas <i>Candida albicans</i>, <i>Actinomyces naeslundii</i>, <i>Fusobacterium nucleatum</i>, and <i>Porphyromonas gingivalis</i> showed no growth after the adhesion and biofilm formation phases. Furthermore, the α-Ag₂WO₄ coatings reduced SARS-CoV-2 titers by up to 2 log₁ ₀ without causing cytotoxic effects in Vero E6 cells. These findings underscore the potential of α-Ag₂WO₄-based coatings as effective antimicrobial and antiviral surfaces, offering promising applications in dental implants and other biomedical devices.