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Although design and fabrication of metallic stents are extensively explored and established, the application of inflatable stents in endovascular treatments is relatively new. Inflatable stents introduce several advantages, such as repositionability and conformability to surrounding anatomic structures. These characteristics make the stent suitable for transcatheter treatment of cardiovascular diseases, such as valvular heart disease, and aortic aneurysms. This paper reports on a rapid and cost‐effective fabrication method, based on soft robotic technology, for the development of inflatable stents made of thermoplastic polyurethane. The stent is an inflatable cylinder that contains an array of bonded regions that form a continuous network, resembling a hexagonal lattice pattern. This pattern prevents the stent from buckling into an irregular shape upon inflation. The effect of this pattern on the maximum burst pressure, thickness, and pull‐out force of the stent is characterized. Finally, a trileaflet polyurethane valve is integrated into the inflatable stent frame to demonstrate its application as a transcatheter heart valve. This work serves as a proof of principle that inflatable stents can be useful in cardiovascular applications where conformability to surrounding tissue is advantageous, such as abdominal aortic aneurysm and aortic valve replacement.

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Bioadhesive polymers can serve as surgical sealants with a wide range of potential clinical applications, including augmentation of wound closure and acute induction of hemostasis. Key determinants of sealant efficacy include the strength and duration of tissue-material adhesion, as well as material biocompatibility. Canonical bioadhesive materials, however, are limited by a tradeoff among performance criteria that is largely governed by the efficiency of tissue-material interactions. In general, increasingly bioreactive materials are endowed with greater bioadhesive potential and protracted residence time, but incite more tissue damage and localized inflammation. One emergent strategy to improve sealant clinical performance is application-specific material design, with the goal of leveraging both local soft tissue surface chemistry and environmental factors to promote adhesive tissue-material interactions. We hypothesize that co-polymer systems with equivalent bioreactive group densities (isoreactive) but different amounts/oxidation states of constituent polymers will exhibit differential interactions across soft tissue types. We synthesized an isoreactive family of aldehyde-mediated co-polymers, and subjected these materials to physical (gelation time), mechanical (bulk modulus and adhesion strength), and biological (in-vitro cytotoxicity and in-vivo biocompatibility) assays indicative of sealant performance. Results show that while bioadhesion to a range of soft tissue surfaces (porcine aortic adventitia, renal artery adventitia, renal cortex, and pericardium) varies with isoreactive manipulation, general indicators of material biocompatibility remain constant. Together these findings suggest that isoreactive tuning of polymeric systems is a promising strategy to circumvent current challenges in surgical sealant applications.How to cite this paper: Ferdous, J., Romito, E., Doviak, H., Moreira, A., Uline, M