Resembling soft tissues, stretchable hydrogels are promising biomaterials for many biomedical applications due to their excellent mechanical robustness. However, conventional stretchable hydrogels with a synthetic polymer matrix are usually bioinert. The lack of cell and tissue adhesiveness of such hydrogels limits their applications. An easy but reliable postgelation functionalization method is desirable. Herein, we report the fabrication of stretchable supramolecular hydrogels cross-linked by multivalent host-guest interactions. Such hydrogels containing thiourea ( TU) functionalities can be bioactivated with a catechol-modified peptide (Cat-RGD) via thiourea-catechol ( TU-Cat) coupling reaction. This postgelation bioactivation of the otherwise bioinert hydrogels not only conjugates bioactive ligands for cell attachment but also introduces and preserves the catechol structures for tissue adhesion. This straightforward fabrication and one-stone-two-bird bioactivation of the stretchable hydrogels may find broad applications in developing advanced soft biomaterials for tissue repair, wound dressing, and lesion sealing.
Keywords: catechol; cyclodextrins; host−guest; multivalent interactions; self-recovery; supramolecular hydrogel; tissue adhesive.