Synthesis of MPB@ZnPc Nanomaterials and Their Application in the Treatment of Periodontitis

Periodontitis treatment remains challenging due to incomplete removal of plaque biofilms, increasing antibiotic resistance, and dysregulated host inflammatory responses. In this study, an MPB@ZnPc nanomaterial was constructed to achieve efficient antibacterial activity through the synergistic effects of photothermal therapy (PTT) and photodynamic therapy (PDT), while also exerting immunomodulatory functions under dark conditions. MPB@ZnPc (mesoporous Prussian blue @ zinc phthalocyanine) was synthesized using a polymer-templating method and systematically characterized. The results demonstrated that the nanomaterial exhibited excellent photothermal conversion efficiency and stability under near-infrared (NIR) irradiation. It also showed strong photocatalytic degradation performance toward methylene blue and rhodamine B, accompanied by substantial reactive oxygen species (ROS) generation. In vitro antibacterial assays revealed that MPB@ZnPc achieved significantly enhanced antibacterial efficacy compared with individual components, with bactericidal rates of 99.61 ± 0.52% against Porphyromonas gingivalis and 99.77 ± 0.32% against Fusobacterium nucleatum. The corresponding biofilm removal rates reached 93.60 ± 3.30% and 93.25 ± 3.30%, respectively. Under dark conditions, the nanomaterial exhibited good biocompatibility toward L929 cells and effectively inhibited lipopolysaccharide (LPS)-induced M1 polarization of macrophages, leading to reduced expression of pro-inflammatory cytokines, including IL-1β, IL-6, and TNF-α. Mechanistically, MPB@ZnPc suppressed the activation of the NF-κB signaling pathway. Overall, MPB@ZnPc provides a promising strategy for precise periodontitis treatment by integrating synergistic antibacterial activity with immunomodulatory effects.