Anisotropic Poly(Ethylene Glycol)/Polycaprolactone Hydrogel–Fiber Composites for Heart Valve Tissue Engineering

TitleAnisotropic Poly(Ethylene Glycol)/Polycaprolactone Hydrogel–Fiber Composites for Heart Valve Tissue Engineering
Publication TypeJournal Article
Year of Publication2014
AuthorsTseng, H, Puperi, DS, Kim, EJ, Ayoub, S, Shah, JV, Cuchiara, ML, West, JL, Grande-Allen, JK
JournalTissue Engineering Part A
Pagination140716112012003
Date Published07/2014
ISSN1937-335X
Abstract

The recapitulation of the material properties and structure of the native aortic valve leaflet, specifically its anisotropy and laminate structure, is a major design goal for scaffolds for heart valve tissue engineering. Poly(ethylene glycol) (PEG) hydrogels are attractive scaffolds for this purpose as they are biocompatible, can be modified for their mechanical and biofunctional properties, and can be laminated. This study investigated augmenting PEG hydrogels with polycaprolactone (PCL) as an analog to the fibrosa to improve strength and introduce anisotropic mechanical behavior. However, due to its hydrophobicity, PCL must be modified prior to embedding within PEG hydrogels. In this study, PCL was electrospun (ePCL) and modified in three different ways, by protein adsorption (pPCL), alkali digestion (hPCL), and acrylation (aPCL). Modified PCL of all types maintained the anisotropic elastic moduli and yield strain of unmodified anisotropic ePCL. Composites of PEG and PCL (PPCs) maintained anisotropic elastic moduli, but aPCL and pPCL had isotropic yield strains. Overall, PPCs of all modifications had elastic moduli of 3.79±0.90 MPa and 0.46±0.21 MPa in the parallel and perpendicular directions, respectively. Valvular interstitial cells seeded atop anisotropic aPCL displayed an actin distribution aligned in the direction of the underlying fibers. The resulting scaffold combines the biocompatibility and tunable fabrication of PEG with the strength and anisotropy of ePCL to form a foundation for future engineered valve scaffolds.

DOI10.1089/ten.tea.2013.0397
Short TitleTissue Eng Part A
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