(692h) Photo-Crosslinked Chondroitin Sulfate a and Chitosan for Extruded Vascularization

In tissue engineering, vascularization is a challenge that is mitigated by induced vascularization or artificial vascular structures or a combination of these methods. In this study, we experimented a method to make vascular structures using Chondroitin Sulfate A (CSA), Chitosan and Collagen. We propose this method to be adapted to a 3D bioprinting setup.

CSA and Chitosan make a polyelectrolytic complex that is known to be effective biomaterial for tissue engineered structures. However, the viscoelastic properties of CSA do not allow for good extrusion. In this study, we photo-crosslinked CSA with each other to make a hydrogel with better viscoelastic properties for extrusion. We methacrylated CSA by reacting with methyl anhyrdride and then photo crosslinked under UV. We found that 3% of CSA with a 0.45 degree of methacrylation showed good viscoelastic properties.

This cross-linked CSA hydrogel was supplemented with endothelial cells and extruded into a Chitosan solution to make hollow fibers. This hydrogel was optimized to be extruded into a Chitosan bath of encapsulated cells. The Chitosan was complemented with Collagen to make the membrane of the hollow fibers more susceptible for endothelial cell attachment. This was evaluated with staining and SEM studies. We further evaluated the viability of the method by making the hollow fibers among Mesenchymal Stem Cells that were encapsulated in capsules of CSA-Chitosan complex. We observed the growth and reported the findings.