Bio-inspired paintable adhesive liquid precipitates as sealing materials

Recently, tissue-adhesive materials have been extensively developed for biomedical purposes, including the sealing of surgical sites to prevent postoperative leakage. In particular, tannic acid (TA)-based composite tissue adhesives have enormous potential for sealing and dressing surgical sites. In this study, a paintable and syringe-extrudable adhesive (P-TAPE) was prepared by mixing pectin, TA, and polyethylene glycol (PEG), followed by centrifugation without external curing. The P-TAPE tissue adhesives showed excellent processability and usability because of their low shear viscosity and mild shear-thinning properties compared to the TA/PEG (TAPE) composite tissue adhesives, and they could be readily injected using 18–26 G needles. The P-TAPE tissue adhesives formed film structures on the tissue after brushing or injecting P-TAPE. In addition, P-TAPE showed low cytotoxicity when examined by co-culture methods using a Transwell system, revealing low acute cytotoxicity and favorable cell recovery. P-TAPE also exhibited excellent underwater adhesive properties with stable interfacial contacts, which were assessed on glass, metal, and porcine intestine tissues in a water bath. In addition, the P-TAPE adhesives could seal 3 mm holes in the intestine with increased bursting pressures. Thus, the P-TAPE adhesives prepared using a facile method exhibited excellent handling, durable tissue adhesion, and effective sealing, indicating their enormous potential as versatile tissue adhesive materials for leakage prevention.