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Abstract For decades, bioadhesive materials have garnered great attention due to their potential to replace sutures and staples for sealing tissues during minimally invasive surgical procedures. However, the complexities of delivering bioadhesives through narrow spaces and achieving strong adhesion in fluid‐rich physiological environments continue to present substantial limitations to the surgical translation of existing sealants. In this work, a new strategy for minimally invasive tissue sealing based on a multilayer bioadhesive patch, which is designed to repel body fluids, to form fast, pressure‐triggered adhesion with wet tissues, and to resist biofouling and inflammation is introduced. The multifunctional patch is realized by a synergistic combination of three distinct functional layers: i) a microtextured bioadhesive layer, ii) a dynamic, blood‐repellent hydrophobic fluid layer, and iii) an antifouling zwitterionic nonadhesive layer. The patch is capable of forming robust adhesion to tissue surfaces in the presence of blood, and exhibits superior resistance to bacterial adhesion, fibrinogen adsorption, and in vivo fibrous capsule formation. By adopting origami‐based fabrication strategies, it is demonstrated that the patch can be readily integrated with a variety of minimally invasive end effectors to provide facile tissue sealing in ex vivo porcine models, offering new opportunities for minimally invasive tissue sealing in diverse clinical scenarios.
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Instant tough bioadhesive with triggerable benign detachment
Bioadhesives such as tissue adhesives, hemostatic agents, and tissue sealants have potential advantages over sutures and staples for wound closure, hemostasis, and integration of implantable devices onto wet tissues. However, existing bioadhesives display several limitations including slow adhesion formation, weak bonding, low biocompatibility, poor mechanical match with tissues, and/or lack of triggerable benign detachment. Here, we report a bioadhesive that can form instant tough adhesion on various wet dynamic tissues and can be benignly detached from the adhered tissues on demand with a biocompatible triggering solution. The adhesion of the bioadhesive relies on the removal of interfacial water from the tissue surface, followed by physical and covalent cross-linking with the tissue surface. The triggerable detachment of the bioadhesive results from the cleavage of bioadhesive’s cross-links with the tissue surface by the triggering solution. After it is adhered to wet tissues, the bioadhesive becomes a tough hydrogel with mechanical compliance and stretchability comparable with those of soft tissues. We validate in vivo biocompatibility of the bioadhesive and the triggering solution in a rat model and demonstrate potential applications of the bioadhesive with triggerable benign detachment in ex vivo porcine models.
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- Award ID(s):
- 1935291
- PAR ID:
- 10164302
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 117
- Issue:
- 27
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- p. 15497-15503
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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