ZIF-8-Based Composites for Enhanced Biofilm Penetration and Synergistic Antibacterial Therapy against Periodontal Pathogens

Periodontitis is initiated by bacterial biofilms, and the removal of plaque is critical in preventing the onset and progression of periodontal diseases, including gingival inflammation, periodontitis, and even alveolar bone resorption. Clinically, mechanical methods are commonly used to remove plaque and calculus. However, conventional methods struggle to access certain regions, such as deep periodontal pockets, root furcations, and dentinal tubules. In these cases, antimicrobial agents are required to eradicate residual pathogenic microorganisms. This study designed a dextran-coated ZIF-8-based composite material (Ce6@ZIF-8/Dex) to enhance biofilm penetration and photodynamic antibacterial efficacy against periodontal pathogens. The photosensitizer, chlorin e6 (Ce6), synergizes with zinc ions (Zn²⁺) from the zeolitic imidazolate framework 8 (ZIF-8) to achieve a combined antibacterial effect and reduce bacterial resistance to single antimicrobial agents. Dextran modification further improves the biofilm penetration capability of the ZIF-8 composite, enhancing its overall antibacterial efficiency. In vivo, Ce6@ZIF-8/Dex demonstrated excellent biocompatibility and antibacterial activity against Porphyromonas gingivalis and Streptococcus mutans. This study presents a promising antibacterial strategy for the prevention and treatment of periodontitis.