Photo-crosslinkable polyrotaxanes (PRXs) via riboflavins (RBFs) were designed for anchoring to biological tissues. In particular, PRXs with amino groups, in which multiple α-cyclodextrins (α-CDs) with amino groups were threaded onto a poly(ethylene glycol) chain end-capped with adamantane molecules, were synthesized. PRXs with ≥33 amino groups were crosslinked to form hydrogels after irradiation with UV-A light in the presence of RBFs. The time for gelation was approximately 15 min at the shortest. The PRX hydrogels showed excellent adhesion and spreading of mouse fibroblasts. Furthermore, when photo-crosslinking on a surface of porcine aorta as model tissues, the PRXs with amino groups strongly anchored to the tissues. Additionally, the PRXs with amino groups were confirmed to successfully close an incision in the tissues. Thus, photo-crosslinkable PRXs may be applied as supermolecule-based tissue adhesive biomaterials for repairing and regenerating biological tissues as tissue engineering scaffolds, flexible tissue-adhesive agents, hemostatic agents, injectable hydrogels, and three-dimensional printable hydrogels to repair biological tissue with complex architecture.

Yoshinori Arisaka, Nobuhiko Yui (2021) Anchoring α-cyclodextrin-based polyrotaxanes to biological tissues via riboflavin-mediated photo-crosslinking, Materials Letters, 290,129460, https://doi.org/10.1016/j.matlet.2021.129460