Hyperbranched Biorefinery Molecule-Regulated Switchable Adhesion and Noninvasive Healing.

Switchable adhesives hold great potential in fields like flexible electronics, soft robotics, and tissue repair, etc. However, creating bio-based switchable adhesives for biomedical use remains challenging due to the difficulty in balancing high strength and a broad adhesion span. Here, we report a dynamic chemical modification strategy based on biorefinery-derived hyperbranched nanoconfinement to fabricate a switchable adhesive for biomedical applications. Microbial fermentation produces hyperbranched biorefinery molecules with nanostructures that address common biomass-related issues like long production cycles, unstable batches, and by-product generation, while also providing abundant binding sites for high-density dynamic bonds. This hyperbranched nanoconfinement enables substantial energy dissipation, facilitating efficient stress redistribution and interfacial reconfiguration at fracture sites, thereby achieving simultaneously excellent adhesive strength and switchable adhesion. The resulting switchable wound bioadhesive exhibits a wide switching span (296 to 17 N/m) and high stability, enabling non-invasive repair with a 94.80% wound closure rate after 10 days, significantly higher than the control (76.07%). This work explores the application of biorefinery molecules in the field of bio-based adhesives and develops a promising candidate for innovating adhesion solutions in the biomedical field.