Development of an electrospinning system integrated with stereolithographic 3D bioprinting

This thesis investigates a novel hybrid biofabrication platform that is an integration of electrospinning and visible light stereolithography (SLA). SLA offers a safe, non-contact method for engineering cell-laden hydrogel structures for tissue engineering. The visible light photoinitiation system is especially favoured since it eliminates harmful UV-radiation used in conventional SLA systems. Electrospinning is a well-known process that has been used to create nanofibrous scaffolds for tissue engineering, however, since the process is random to some extent and hard to control, it has been a challenge obtaining complex 3D structures made of nanofibrous materials. In this work, we first develop and optimize our own lab-made electrospinning system, with the alginate/polyethylene oxide blend to yield bead-free, smooth nanofibers. Based on our findings from here, we electrospun other well-known biomaterials like gelatin-methacrylate, in order to incorporate the same visible-light based crosslinking strategy for nanofibrous mats. In literature, most instances of GelMA nanofiber crosslinking have been cited as having been a result of UV-radiation based photocrosslinking. To study whether visible light can be used, we model the photopolymerization process computationally to understand the reaction mechanism to greater detail. We finally propose two methodologies, one that seeks to quickly crosslink alginate-based nanofibers by introducing them to calcium-containing GelMA hydrogels. The other focusses on selectively photocrosslinking GelMA based nanofiber mats. The limitations and advantages of deploying these methodologies is also investigated. While a more rigorous investigation is needed, our early findings indicated that it is indeed possible to photocrosslink nanofiber mats using visible light, however, better solvent selection and a cell-based characterization study are of need.Applied Science, Faculty ofEngineering, School of (Okanagan)Graduat