Spatiotemporal Catalytic Nanozymes Microneedle Patches with Opposite Properties for Wound Management

Reactive oxygen species (ROS)-mediated biological catalysis involves serial programmed enzymatic reactions and plays an important part against infectious diseases; while the spatiotemporal control of catalytic treatment to break the limitations of the disease microenvironment is challenging. Here, a novel spatiotemporal catalytic microneedles patch (CMSP-MNs) integrated with dual-effective Cu₂ MoS₄ (CMS) and polydopamine (PDA) nanoparticles (NPs) for breaking microenvironment restrictions to treat wound infections is designed. Since CMS NPs are loaded in the needles, CMSP-MNs can catalytically generate diverse ROS to cause effective bacterial inactivation during bacterial infection process. Besides, PDA NPs are encapsulated in the backing layer, which facilitate ROS elimination and oxygen production for solving hypoxic problems in wound microenvironment and alleviating the expression of inflammatory factors during the inflammation process. Based on these features, it is demonstrated through cell and animal experiments that these nanozymes-integrated MNs patches can realize selective regulation of ROS level with bacterial inactivation and inflammatory treatment, resulting in minimized side effects of over-production ROS and effective anti-infected treatment. It is believed that the presented MNs can provide a new therapeutic strategy with spatiotemporal adjustable catalytic properties in biomedical areas.