IADR Abstract Archives
Purine-Based Ir(III) Photosensitizers for Efficient Treatment of Periodontal Inflammation
Objectives: This study explores photodynamic therapy (PDT) as a novel bactericidal approach for periodontitis treatment. To enhance PDT efficiency, we synthesized a series of purine-based Ir(III) photosensitizers using a donor-acceptor (D-A) strategy to optimize photodynamic properties.
Methods: Six Ir(III) complexes were synthesized with purine ligands modified by electron-donating/withdrawing groups and characterized using 1H NMR, 13C NMR, HRMS, and single-crystal X-ray diffraction. Their photophysical and photodynamic properties were assessed via absorption/emission spectroscopy, ROS indicator assays, and EPR spectroscopy. Antibacterial efficacy and biofilm disruption were evaluated with SEM and CLSM, while therapeutic effects and biocompatibility were analyzed using micro-CT, histological staining (H&E, Masson, immunohistochemistry), and RNA-seq in a rat periodontitis model.
Results: 1. Six purine-based Ir(III) complexes with different electron donating/withdrawing groups were successfully synthesized. The single crystal structure showed that purine formed a stable structure around the Ir(III) core. The mechanism of photosensitizers was discussed by theoretical calculation.
2. The Ir(III) complexes exhibited high production of type I and II reactive oxygen species (ROS), effectively disrupting biofilms and inhibiting periodontal pathogen growth by over 99.99% with minimal cytotoxicity.
3. In a ligation-induced rat periodontitis model, the Ir(III) complexes significantly reduced inflammatory cell infiltration and bone loss. RNA-seq analysis revealed PDT accelerated periodontal tissue repair by promoting cellular stress responses and cytoskeleton remodeling.
Conclusions: This study developed a series of purine-based Ir(III) complexes for photodynamic therapy of periodontitis with significant antibacterial, anti-inflammatory and tissue-repair properties, which provided potential strategies for the clinical management of periodontal diseases.
Methods: Six Ir(III) complexes were synthesized with purine ligands modified by electron-donating/withdrawing groups and characterized using 1H NMR, 13C NMR, HRMS, and single-crystal X-ray diffraction. Their photophysical and photodynamic properties were assessed via absorption/emission spectroscopy, ROS indicator assays, and EPR spectroscopy. Antibacterial efficacy and biofilm disruption were evaluated with SEM and CLSM, while therapeutic effects and biocompatibility were analyzed using micro-CT, histological staining (H&E, Masson, immunohistochemistry), and RNA-seq in a rat periodontitis model.
Results: 1. Six purine-based Ir(III) complexes with different electron donating/withdrawing groups were successfully synthesized. The single crystal structure showed that purine formed a stable structure around the Ir(III) core. The mechanism of photosensitizers was discussed by theoretical calculation.
2. The Ir(III) complexes exhibited high production of type I and II reactive oxygen species (ROS), effectively disrupting biofilms and inhibiting periodontal pathogen growth by over 99.99% with minimal cytotoxicity.
3. In a ligation-induced rat periodontitis model, the Ir(III) complexes significantly reduced inflammatory cell infiltration and bone loss. RNA-seq analysis revealed PDT accelerated periodontal tissue repair by promoting cellular stress responses and cytoskeleton remodeling.
Conclusions: This study developed a series of purine-based Ir(III) complexes for photodynamic therapy of periodontitis with significant antibacterial, anti-inflammatory and tissue-repair properties, which provided potential strategies for the clinical management of periodontal diseases.