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bioRxiv · 10.1101/2020.12.12.422505

Barnacle-Inspired Paste for Instant Hemostatic Tissue Sealing

Abstract

Whilst sealing damaged tissues by adhesives has potential advantages over suturing or stapling, existing tissue adhesives cannot form rapid or robust adhesion on tissues covered with body fluids such as blood. In contrast, the glues of barnacles, consisting of a lipid-rich matrix and adhesive proteins, and can strongly adhere to wet and contaminated surfaces. Here we report a barnacle-inspired paste capable of forming instant robust hemostatic sealing of diverse tissues. The paste is composed of a hydrophobic oil matrix and bioadhesive microparticles to implement the barnacle-inspired mechanism to repel blood through the hydrophobic matrix. Subsequently, the bioadhesive microparticles crosslink with underlying tissues under gentle pressure. The barnacle-inspired paste can provide tough (interfacial toughness over 300 J m-2) and strong (shear and tensile strength over 70 kPa, burst pressure over 350 mmHg) hemostatic sealing of a broad range of tissues within five seconds. We validate in vitro and in vivo biocompatibility and biodegradability of the barnacle-inspired paste in rodent models. We further demonstrate potential applications of the barnacle-inspired paste for instant hemostatic sealing in ex vivo porcine aorta, in vivo rat liver and heart models.

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Yuk, H., Wu, J., Mao, X., Varela, C. E., Roche, E. T., Nabzdyk, C. S., Zhao, X.. 2020-12-12. Barnacle-Inspired Paste for Instant Hemostatic Tissue Sealing. https://doi.org/10.1101/2020.12.12.422505

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