Replenishing interfacial lubrication: A cartilage–inspired polyzwitterionic dressing for spatiotemporal healing of friction–prone diabetic wound

Frequent frictions and overexpressed reactive oxygen-nitrogen species are two prominent barriers to friction-prone diabetic wound healing. Current commercial dressings fail to adaptively replenish the interfacial lubrication and restore immune homeostasis. By mimicking the lubrication and antioxidation properties of cartilage, we develop an engineered polyzwitterionic dressing by upcycling kitchen waste (eggshell membrane, ESM). With the sequential chemical modification of ergothioneine (EGT) and active-ester-contained zwitterionic copolymer, the resulting EP-ESM dressing replenishes interfacial lubrication (μ = 0.0204) by thickening the hydrated fluid film and thinning the tissue fluid. We quantify the mathematical correlation between time-controlled lubrication and responsive EGT release, confirming the improved efficiency of lubrication replenishment and the inherent lubricity of EP-ESM dressing. In addition, it demonstrates enhanced anti-oxidation performance by synergistic proton-transfer and electron-transfer mechanisms, thereby preserving mitochondrial energy metabolism. EP-ESM also exhibit an immunoregulatory property (2.77-fold increment in CD206 and 68.04% reduction in CD86), as analyzed using RNA-sequencing and qPCR. Consequently, in the full-thickness wound at the dorsal neck of diabetic rats, EP-ESM dressing shows a superior spatiotemporal healing performance compared with pristine ESM and commercial Tegaderm dressings, as evidenced by the increased wound closure rate, more collagen deposition and mature, and rapid angiogenesis. This study offers a promising regenerative strategy that integrates immunoregulation with dynamic lubrication replenishment for chronic wound repair and other tribological diseases.