Cellulose nanofibril-directed interfacial assembly of electroactive hydrogel dressings for diabetic wound repair

The development of high-value bio-based products from cellulose-rich plant and forest biomass is an important route for expanding the industrial applications of renewable plant resources. Cellulose nanofibrils, as nanoscale derivatives of natural cellulose, combine high aspect ratio, abundant hydroxyl groups, mechanical robustness, and interfacial adaptability, making them attractive building blocks for functional bio-based materials. However, cellulose nanofibrils are still frequently used as passive reinforcing fillers, and their potential as active structural and interfacial regulators in multifunctional hydrogel products remains insufficiently explored. Herein, an electroactive hydrogel reinforced with TEMPO-oxidized cellulose nanofibrils (CNF) was developed as a bio-based dressing for diabetic wound management. In this system, CNF provided a reinforcing nanofibrous skeleton and simultaneously functioned as an interfacial organizing platform. The hydroxyl-rich CNF network participated in reversible boronic ester crosslinking with polyvinyl alcohol and borax, endowing the hydrogel with mechanical stability, self-healing ability, swelling regulation, and pH-responsive doxycycline release. Meanwhile, CNF stabilized MXene nanosheets and promoted conductive pathway formation, while polydopamine (PDA)-mediated silver nanoparticle immobilization introduced adhesive and antibacterial interfaces. Therefore, CNF served as an active structural and interfacial regulator that connected the dynamic polymer network, conductive MXene nanosheets, the PDA adhesive layer, and the silver nanoparticle-based antibacterial interface. This work demonstrates a cellulose-derived strategy for constructing multifunctional bio-based hydrogel products and highlights the potential of CNF in high-value biomedical applications of renewable biomass.