Systematic design of an advanced open-source 3D bioprinter for extrusion and electrohydrodynamic-based processes

The goal of scaffold-based tissue engineering is to create synthetic replacements for natural tissues. Since tissues are comprised of composite structures, it is challenging for a single biomaterial to appropriately mimic the cellular and extracellular natural environment. To incorporate multiple biomaterials into multiphasic scaffolds, additive manufacturing (3D printing) technologies have arisen as a universal scaffold fabrication platform. However, combining multiple printed biomaterials is technically difficult since many printing processes rely on fundamentally different operating principles. Furthermore, commercial equipment is often cost prohibitive, and there remains limited open-source alternatives. To address the lack of equipment, systematic engineering design was applied to build an open-source 3D bioprinter capable of printing with multiple materials using multiple technologies. The design requirements were identified through a user-centred design process with the overarching aim of being a multi-material, multi-technology system while adhering to engineering standards (AS IEC 61010). The system was constructed to be open source, and detailed diagrams, parts lists, computer-aided design (CAD) models, standard operating procedures (SOP’s) and cost breakdowns on each subsystem are provided. To validate and test the design, 4 popular extrusion and electrohydrodynamic printing processes were tested: inks, solution electrospinning, melt electrospinning and melt extrusion. To demonstrate the utility of the Biofabricator for creating multi-material, multi-technology scaffolds, 4 multiphasic scaffolds were designed and presented as case studies. The open-source Biofabricator is an advanced bioprinting platform capable of fabricating multi-material, multi-technology scaffolds to support cutting-edge future research in tissue engineering.