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Abstract Wound closure in surgeries is traditionally achieved using invasive methods such as sutures and staples. Adhesion‐based wound closure methods such as tissue adhesives, sealants, and hemostats are slowly replacing these methods due to their ease of application. Although several chemistries have been developed and used commercially for wound closure, there is still a need for better tissue adhesives from the point of view of toxicity, wet‐adhesion strength, and long‐term bonding. Catechol chemistry has shown great promise in developing wet‐set adhesives that meet these criteria. Herein, we have studied the biocompatibility of a catechol‐based copolymer adhesive, poly([dopamine methacrylamide]‐co‐[methyl methacrylate]‐co‐[poly(ethylene glycol) methyl ether methacrylate]) or poly(catechol‐MMA‐OEG), which is soluble in water. The adhesive was injected subcutaneously in a mouse model on its own and in combination with a sodium periodate crosslinker. After 72 h, 4 weeks, and 12 weeks, the mice were euthanized and subjected to histopathological analysis. Both adhesives were present and still palpable at the end of 12 weeks. The moderate inflammation observed for the poly(catechol‐MMA‐OEG) cohort at 72 h had reduced to mild inflammation at the end of 12 weeks. However, the moderate inflammatory response observed for the poly(catechol‐MMA‐OEG) + crosslinker cohort at 72 h had not subsided at 12 weeks.
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Sprayable Hydrogel Sealant for Gastrointestinal Wound Shielding
Abstract Naturally occurring internal bleeding, such as in stomach ulcers, and complications following interventions, such as polyp resection post‐colonoscopy, may result in delayed (5–7 days) post‐operative adverse events—such as bleeding, intestinal wall perforation, and leakage. Current solutions for controlling intra‐ and post‐procedural complications are limited in effectiveness. Hemostatic powders only provide a temporary solution due to their short‐term adhesion to GI mucosal tissues (less than 48 h). In this study, a sprayable adhesive hydrogel for facile application and sustained adhesion to GI lesions is developed using clinically available endoscopes. Upon spraying, the biomaterial (based on polyethyleneimine‐modified Pluronic micelles precursor and oxidized dextran) instantly gels upon contact with the tissue, forming an adhesive shield. In vitro and in vivo studies in guinea pigs, rabbits, and pig models confirm the safety and efficacy of this biomaterial in colonic and acidic stomach lesions. The authors' findings highlight that this family of hydrogels ensures prolonged tissue protection (3–7 days), facilitates wound healing, and minimizes the risk of delayed complications. Overall, this technology offers a readily adoptable approach for gastrointestinal wound management.
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- Award ID(s):
- 2335845
- PAR ID:
- 10498289
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 36
- Issue:
- 24
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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