A Core-Shell-Type Nanosystem Promotes Diabetic Wound Healing Through Photothermal-Responsive Release of Transforming Growth Factor β

The treatment of diabetic wounds remains a major clinical challenge owing to bacterial infection, defects in angiogenesis, and the corresponding inhibition of cell activity and extracellular matrix deposition. In this study, a core-shell-type nanosystem was developed using graphdiyne (GDY) nanoparticles covered with gelatin to investigate its effects on diabetic wound healing. The nanoparticles were loaded with transforming growth factor β (TGF-β) via electrostatic self-assembly to promote angiogenesis and cell migration. The photothermal effects of GDY nanoparticles were applied to achieve controllable drug release and antibacterial properties. This nanosystem could rapidly release TGF-β after irradiation by near-infrared rays (NIR) without damaging its biological activities. The associated photothermal antibacterial activity was observed after 30 seconds irradiation of nanoparticles, and the temperature was set at a safe range (<49.6 °C). Besides, the gels possessed good biocompatibility and promoted cell migration in vitro. After implantation, the hydrogels group showed a higher wound healing rate than the control group in diabetic wound mouse models after 14 days and exhibited evident tissue regeneration, including angiogenesis and extracellular matrix deposition. This study presents a method for fabricating antibacterial wound dressings and an effective NIR-response strategy for designing drug-delivery nanosystems loaded with cellular factors.