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Title: Engineering a Hierarchical Biphasic Gel for Subcutaneous Vascularization
Abstract Implanted cell‐containing grafts require a robust and functional vasculature to supply oxygen and nutrients, as well as clear metabolic waste products. However, it remains challenging to fabricate tunable, vascular‐promoting scaffolds without incorporating additional biologics. Here, a biphasic gel consisting of a highly porous aerogel and a degradable fibrin hydrogel for inducing vascularization is presented. The highly porous (>90%) and stable aerogel is assembled from short microfibers by being dispersed in an aqueous solution that can be 3D printed into various configurations. The biphasic gel demonstrates good compression‐resistance: 70.30% Young's modulus is recovered over 20 cycles of 65% compression under water. Furthermore, it is confirmed that tissue cells and blood vessels can penetrate a thick (≈3 mm) biphasic gel in the subcutaneous space of mice. Finally, the biphasic gel doubles the vascular ingrowth compared to a composite of a commercial surgical polyester felt and a fibrin hydrogel upon subcutaneous implantation in mice after 4 weeks. The design of this biphasic gel may advance the development of vascularized scaffolds.  more » « less
Award ID(s):
1719875
PAR ID:
10373092
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Healthcare Materials
Volume:
11
Issue:
19
ISSN:
2192-2640
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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