A Targeted Core–Shell ZIF-8/Au@Fe₃O₄ Platform with Multiple Antibacterial Pathways for Infected Skin Wound Regeneration

Bacterial infections seriously retard skin wound healing. To enhance the antibacterial efficiency and subsequent skin regeneration, a core-shell structured therapeutic platform, named FZAM, was designed with multiple antimicrobial pathways. FZAM consists of nanosized Fe₃O₄ as the core and ZIF-8 loaded with Au nanoparticles (NPs) and maltodextrin as the shell. Fe₃O₄ and Au NPs form a heterojunction that generates hyperthermia and abundant reactive oxide species (ROS) under near-infrared (NIR) irradiation. This heterojunction also exhibits outstanding peroxidase-like activity. When bacteria invade, maltodextrin plays a targeting effect to increase the interaction between FZAM and bacteria, and with the synergistic action of NIR-induced hyperthermia and ROS as well as Zn²⁺ from ZIF-8, FZAM kills more than 99% of bacteria at 200 μg mL^-1. Fortunately, FZAM is cytocompatible and even promotes the biofunctions of fibroblasts and endothelial cells. In infected skin wound models, FZAM sterilizes bacteria with NIR irradiation and subsequently reduces the inflammatory response and accelerates skin regeneration. This work provides a core-shell structured therapy platform for treating infection with the assistance of NIR irradiation and helping skin wound healing.