Bimetallic nanozymes for effectively removing Enterococcus faecalis biofilms in pulp and periapical infection...

Pulpal and periapical infections, primarily caused by the biofilms of Enterococcus faecalis (E. faecalis), pose significant challenges due to their resistance to eradication, making them prevalent oral health concerns. Herein, we synthesized a bimetallic Zn-Fe nanozymes (ZFNs) with enhanced peroxidase-like (POD-like) activity, capable of activating hydrogen peroxide (H₂O₂) into highly reactive hydroxyl radicals to combat E. faecalis biofilms. The incorporation of Zn elements effectively optimizes the electronic structure of the reactive Fe sites, significantly improving the POD-like activity of ZFNs. Consequently, a trace amount of ZFNs (20 μg mL^-1) combined with H₂O₂ (200 μM) achieved efficient E. faecalis inactivation (95 %) and disrupts biofilm formation. Notably, in a root canal infection model, ZFNs demonstrate a biofilm-clearing effect comparable to that of 3 % sodium hypochlorite NaOCl, a clinical drug) and exhibit satisfactory biosafety. In summary, ZFNs hold promise as a root canal irrigation solution for treating pulpal and periapical infections, offering new possibilities for addressing root canal infection challenges.