Simple Component Self-Gelling Powders As Multifunctional Tissue Adhesives for Sutureless Wound Healing

For decades, bio-adhesives have gained great attention due to their potency to replace sutures. However, facile fabrication of asymmetric bioadhesives simultaneously with robust adhesion to non-planar wet tissues, effective resistance to postoperative tissue adhesion and bacterial associated infection remains a great challenge. Here, we report a simple component & ready-to-use self-gelling adhesive powder (copolymer of acrylic acid and 2-aminoethyl methacrylate, AMA) combined with an anti-adhesive powder (a mixture of zwitterionic sulfobetaine copolymer and an acrylic homopolymer, AASB) as the multifunctional tissue adhesive for sutureless wound closure & healing. The adhesive powder is capable of forming a physically cross-linked hydrogel within 5 s by absorbing water and strongly sticking to diverse non-planar wet tissues (adhesion strength up to 63 kPa, bursting pressure up to 350 mmHg within 24 h) with a broad-spectrum bactericidal efficiency (99.4 %, 96.2 % and 99.9 % against S. aureus, E. coli and MRSA). The integrated AASB hydrogel layer can effectively prevent cell/tissue adhesion and suppress hemolysis ratio & inflammation of the adhesive. Moreover, the AMA/AASB Janus hydrogel adhesive exhibited durable adhesive/anti-adhesive capability (at least for 30 days) and good biodegradability (within 60 days) in vivo, comparable sealing & repairing of gastric defects but superior anti-postoperative tissue adhesion to the clinic used fibrin glue. Such a simple-component, ready-to-use and multifunctional powder based adhesive offer new opportunities for minimal invasive sutureless tissue sealing in many clinical applications.