Microenvironment-Driven Fenton Nanoreactor Enabled by Metal-Phenolic Encapsulation of Calcium Peroxide for Effective Control of Dental Caries.

Caries are one of the most common oral diseases caused by pathogenic bacterial infection, which are widespread and persistent harmful to human health. Using nanoparticles to invade biofilms and produce reactive oxygen species (ROS) in situ is a promising strategy for killing bacteria and disrupting the structure of biofilm. In this work, we report a biofilm-targeting Fenton nanoreactor that can generate ROS responsive to the cariogenic microenvironment. The nanoreactor was constructed by metal-phenolic encapsulation of calcium peroxide (CaO 2 ) followed by modification with a biofilm targeting ligand dextran. Within the cariogenic biofilm, the Fenton nanoreactor was activated by acidic microenvironment to be decomposed into H 2 O 2 and iron ions, triggering Fenton-like reaction to generate ROS that can eliminate the biofilm by breaking down EPS and killing of cariogenic bacteria. Meanwhile, the depletion of excess proton in biofilm lead to a reversal of the cariogenic microenvironment. The Fenton nanoreactor can effectively inhibit biofilm formation of S.mutans on ex vivo human teeth and was effective in preventing caries meanwhile maintaining the oral microbial diversity in rat caries infection model. This work provides a novel and efficient modality for acid microenvironment-driven ROS therapy. This article is protected by copyright. All rights reserved.