Multi-material integration in light-based Volumetric Bioprinting: pathways to enhanced precision and complexity in scaffold fabrication

In regenerative medicine, layer-by-layer additive manufacturing has been pivotal in developing intricate 3D tissue scaffolds, yet challenges remain in the fast production of cell-laden structures of clinically relevant (centimeter-scale) sizes. Volumetric Bioprinting (VBP) is a recent optical additive manufacturing technique which facilitates rapid creation of such structures by using spatial light modulation to deliver precise tomographic patterns into a rotating volume of cell-laden photoresin, thus allowing for rapid, volumetric crosslinking of materials. Our research enhances VBP by integrating extrusion and electrohydrodynamic printing, thus optimizing multi-cell and multi-material constructs. Using photoresponsive biopolymers and polycaprolactone-based meshes, we have crafted complex cell-laden 3D forms with VBP, introducing diverse features unseen with conventional techniques. With applications for multi-walled blood vessel engineering and specialized cell growth platforms, our findings emphasize the transformative role of optics in biofabrication, suggesting VBP's potential in replicating tissue intricacies and advancing regenerative medicine.