On-chip fabrication of movable toroidal cell structures using photo-crosslinkable biodegradable hydrogel

In this research, we fabricated movable toroidal cell structures inside a microfluidic device for tissue engineering applications. A photo-crosslinkable biodegradable hydrogel gelatin methacrylate (GelMA) was employed to encapsulate biological cells for assembling cell structures. The UV light power and the concentration GelMA hydrogel were optimized to achieve both fabrication of microstructures and live condition of cells. The two-layered toroidal cell structures were fabricated which can mimic the multi-layered structure of blood vessels. The movable microstructures were achieved by the water repellent coating on the substrate surface. Finally, on-chip fabrication of GelMA microstructures and peeling off of the fabricated microstructures were achieved using a microfluidic chip. The results indicate that the fabricated movable GelMA microstructures can be used for further three dimensional assembly to achieve vascular-like tube structures.