A Coenzyme‐Based Deep Eutectic Supramolecular Polymer Bioadhesive

Abstract α‐lipoic acid (LA), a coenzyme, has proved to have excellent antioxidant and antibacterial activities; however, its intrinsic hydrophobicity and metastability of polyLA remains a major challenge for the application of LA‐based bulk materials in biomedical field. Herein, a self‐stabilized LA‐based deep eutectic supramolecular polymer ( LA‐DESP) adhesive is created by one‐step heating the mixture of LA and sodium α‐lipoate (LA‐Na) (S‐, R‐isomer, racemate) without introducing any exogenous stabilizing molecules. The underlying deep eutectic effect in LA/LA‐Na is unveiled to be originated from the multiple hydrogen bonds between polyLA and polyLA‐Na, which not only prevent polyLA depolymerization but also lower the melting point of LA‐DESP to the near body and pathological temperature. Copolymerization of LA and LA‐Na slows down the dissociation of polyLA‐Na, thus affording sustainable release of bioactive LA‐based small molecules and satisfactory antioxidant and antibacterial functions. Also, the LA‐DESP exhibits fast and tough adhesion to diverse substrates, including wet tissues, relying on its in situ curing property and rich carboxyl groups. The LA‐DESP is explored as a tissue sealant, which can well replace surgical suture to enhance the wound healing of skin incision in a rat model. The unprecedented deep eutectic effect will provide a new strategy for the development of LA‐based bioadhesives.