Engineering a platelet-rich plasma-based multifunctional injectable hydrogel with photothermal, antibacterial, and antioxidant properties for skin regeneration.

Wound healing remains a significant challenge worldwide, necessitating the development of new wound dressings to aid in the healing process. This study presents a novel photothermally active hydrogel that contains platelet-rich plasma (PRP) for infected wound healing. The hydrogel was formed in a one pot synthesis approach by mixing alginate (Alg), gelatin (GT), polydopamine (PDA), and PRP, followed by the addition of CaCl as a cross-linker to prepare a multifunctional hydrogel (AGC-PRP-PDA). The hydrogel exhibited improved strength and good swelling properties. PDA nanoparticles (NPs) within the hydrogel endowed them with high photothermal properties and excellent antibacterial and antioxidant activities. Moreover, the hydrogels sustained the release of growth factors due to their ability to protect PRP. The hydrogels also exhibited good hemocompatibility and cytocompatibility, as well as high hemostatic properties. In animal experiments, the injectable hydrogels effectively filled irregular wounds and promoted infected wound healing by accelerating re-epithelialization, facilitating collagen deposition, and enhancing angiogenesis. The study also indicated that near-infrared light improved the healing process. Overall, these hydrogels with antibacterial, antioxidant, and hemostatic properties, as well as sustained growth factor release, show significant potential for skin regeneration in full-thickness, bacteria-infected wounds.