Microneedles loaded with l-arginine-modified puerarin-derived carbon nanoparticles improved treatment of diabetic wound via photothermal and nitric oxide-based gas therapy.

Due to the high-glucose environment of diabetic wounds, a significant proliferation of bacteria at wound site can occur, resulting in an inflammatory response that extends the inflammatory phase of the wound, thereby complicating the healing process in diabetic wounds. Eliminating the proliferation of bacteria plays a crucial role in promoting the healing of diabetic wounds. Under near-infrared (NIR) laser irradiation, l-arginine (L-Arg) -modified natural product puerarin (Pue)-derived carbon nanoparticles (l-Arg-CNP) not only exhibited excellent photothermal effects but also produced reactive oxygen species (ROS) to react with l-Arg for producing Nitric Oxide (NO), thus contributing to a synergistic antibacterial therapy in diabetic wound. At the same time, l-Arg-CNP retained Pue's original characteristics to promote cell proliferation and angiogenesis. Following the loading of l-Arg-CNP into microneedle patches (l-Arg-CNP@MN), it can deliver them into the deeper wound, effectively killing bacteria, reducing inflammatory infiltration, and promoting neovascularization at the wound site. It offers an effective therapeutic strategy for treating diabetic wound healing.