A dual functional theranostic microneedle patch for immunomodulation and real time monitoring in diabetic wound...

The management of diabetic wound is limited by the absence of delivery systems that can dynamically respond to the complex pathological microenvironment. Herein, we have engineered a dual-functional theranostic microneedle (MN) patch for intelligent diabetic wound therapy.

The patch (termed MNs@Z/CP) features a spatially designed bilayer architecture: the needle tips are loaded with a catalytic nanozyme (ZTCG) for on-demand therapy, exhibiting cascade superoxide dismutase (SOD)- and catalase (CAT)-mimetic activities to simultaneously alleviate oxidative stress and hypoxia while combating bacterial infection; the backing layer incorporates a cerium metal-organic framework (Ce-MOF)-based visual sensor for real-time monitoring of wound H₂O₂ levels.

MNs@Z/CP not only exhibited multimodal antibacterial and anti-inflammatory effects but also reprogrammed the immune microenvironment by activating the Nrf2/HO-1 pathway to shift macrophages from a pro-inflammatory (M1) to a pro-healing (M2) phenotype. In both diabetic and methicillin-resistant Staphylococcus aureus (MRSA)-infected diabetic wound models, the patch significantly accelerated wound closure, promoting angiogenesis, collagen deposition, and re-epithelialization.

This work pioneers a theranostic platform that integrates real-time diagnostic, controlled catalytic therapy, and immunomodulatory therapy, providing a viable approach to the autonomous management of chronic wounds.