Waste-to-Treasure: Nanozyme-Integrated Photocatalytic Microneedles Reconfigure Diabetic Burn Wounds via Endogenous Glucose-to-H2 Conversion and Adaptive Hydrogel Scaffolding.

The recalcitrance of diabetic burn wounds is rooted in a hostile microenvironment characterized by a pathological surplus of glucose, advanced glycation end products (AGEs), and reactive oxygen species. Standard enzymatic and photocatalytic interventions are often limited by instability or the toxic accumulation of hydrogen peroxide (H2O2), leading to secondary oxidative injury. In this study, we developed a metabolism-driven microneedle platform (MN-PCN) by integrating photocatalytic Pt@Pd-PCN222-NH2 (PCN) into a self-adjusting, antimicrobial, and antioxidant hydrogel matrix featuring highly moisture-resilient adhesion. Adopting a waste-to-treasure logic, the system exploits endogenous glucose as a primary reductant to facilitate continuous hydrogen (H2) evolution, effectively suppressing the AGEs/receptor for AGEs signaling axis. Critically, the MN-PCN system actively scavenges catalytic H2O2 byproducts and environmental reactive oxygen species through the synergistic catalase-mimetic activity of the PCN sites and the antioxidant hydrogel matrix, thereby circumventing oxidative damage. Simultaneously, the microneedle architecture undergoes an in situ transition into a protective hydrogel upon contact with wound exudate, establishing a physical barrier that minimizes infection and fosters cellular infiltration. By neutralizing inflammatory circuit and accelerating vascularization, MN-PCN restores both physiological and structural equilibrium. This integrated strategy provides a sophisticated framework for complex wound management through systemic, metabolism-driven microenvironmental reconfiguration.