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Abstract Pulmonary air leak is the most common complication of lung surgery, contributing to post‐operative morbidity in up to 60% of patients; yet, there is no reliable treatment. Available surgical sealants do not match the demanding deformation mechanics of lung tissue; and therefore, fail to seal air leak. To address this therapeutic gap, a sealant with structural and mechanical similarity to subpleural lung is designed, developed, and systematically evaluated. This “lung‐mimetic” sealant is a hydrofoam material that has alveolar‐like porous ultrastructure, lung‐like viscoelastic properties (adhesive, compressive, tensile), and lung extracellular matrix‐derived signals (matrikines) to support tissue repair. In biocompatibility testing, the lung‐mimetic sealant shows minimal cytotoxicity and immunogenicity in vitro. Human primary monocytes exposed to sealant matrikines in vitro upregulate key genes (MARCO, PDGFB, VEGF) known to correlate with pleural wound healing and tissue repair in vivo. In rat and swine models of pulmonary air leak, this lung‐mimetic sealant rapidly seals air leak and restores baseline lung mechanics. Altogether, these data indicate that the lung‐mimetic sealant can effectively seal pulmonary air leak and promote a favorable cellular response in vitro.
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Strain-stiffening seal
A strain-stiffening seal is soft to accommodate installation but stiff to block fluid flow. Leak by elastic deformation or rupture? We construct diagrams in which the two modes of leak are demarcated.
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- Award ID(s):
- 2011754
- PAR ID:
- 10500404
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Soft Matter
- Volume:
- 18
- Issue:
- 15
- ISSN:
- 1744-683X
- Page Range / eLocation ID:
- 2992 to 3003
- 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/10.1039/D2SM00068G
