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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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Adhesive anti-fibrotic interfaces on diverse organs
Abstract Implanted biomaterials and devices face compromised functionality and efficacy in the long term owing to foreign body reactions and subsequent formation of fibrous capsules at the implant–tissue interfaces1–4. Here we demonstrate that an adhesive implant–tissue interface can mitigate fibrous capsule formation in diverse animal models, including rats, mice, humanized mice and pigs, by reducing the level of infiltration of inflammatory cells into the adhesive implant–tissue interface compared to the non-adhesive implant–tissue interface. Histological analysis shows that the adhesive implant–tissue interface does not form observable fibrous capsules on diverse organs, including the abdominal wall, colon, stomach, lung and heart, over 12 weeks in vivo. In vitro protein adsorption, multiplex Luminex assays, quantitative PCR, immunofluorescence analysis and RNA sequencing are additionally carried out to validate the hypothesis. We further demonstrate long-term bidirectional electrical communication enabled by implantable electrodes with an adhesive interface over 12 weeks in a rat model in vivo. These findings may offer a promising strategy for long-term anti-fibrotic implant–tissue interfaces.
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- Award ID(s):
- 1935291
- PAR ID:
- 10569757
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Nature
- Volume:
- 630
- Issue:
- 8016
- ISSN:
- 0028-0836
- Page Range / eLocation ID:
- 360 to 367
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41586-024-07426-9
