Multifunctional PDA/ZIF8 based hydrogel dressing modulates the microenvironment to accelerate chronic wound healing by ROS scavenging and macrophage polarization

An ideal wound dressing has both efficient antimicrobial and anti-inflammatory properties, as well as the potential to regulate the immune microenvironment for the treatment of chronically infected wounds. Herein, a novel multifunctional hydrogel wound dressing (HPZ8) was developed for wound healing by incorporating polydopamine Zeolite Imidazole Framework 8 (PDA-ZIF8) nanoparticles into a dynamic cross-linked network consisting of hydrazide-modified hyaluronic acid (HA-CDH) and oxidized hyaluronic acid (HA-CHO). The results suggested that the HPZ8 hydrogel could be injected into the wound to form a barrier, facilitating tissue adhesion and rapid hemostasis. After loaded with PDA-ZIF8 nanoparticles, the hydrogel exhibited excellent antioxidant and photothermal antimicrobial properties, which could effectively scavenge ROS, reduce oxidative stress and eliminate bacterial infections. Especially, near-infrared (NIR) irradiation strengthened the photothermal therapy (PTT). Besides, HPZ8 hydrogel could release zinc ions to promote cell migration, angiogenesis and M2 polarization of macrophages, accelerating macrophage transition from inflammation to proliferation stages, thus promoting infected wound healing. Therefore, the HPZ8 multifunctional hydrogel dressing has application prospects for the therapy of chronic infected wounds.