3D Bioprinter Design and Development for Printing of UV Crosslinked Hydrogels under Sterile Condition

3-Dimensional (3D) Bioprinters use biomaterials to replicate parts that imitate the natural tissues, bones, and blood vessels. Hydrogels have been frequently preferred biomaterials in this technology, since they support cell proliferation due to their permeable structure that swells in water and resembles natural extracellular matrix (ECM). Photopolymerization-based hydrogel bioinks are suitable for bioprinting methods due to their advantages such as rapid gelation at room temperature, high printing accuracy and sensitive reaction process. Ultraviolet (UV) crosslinking method for photopolymerization during bioprinting is widely applied in extrusion based bioprinting as a simple and convenient method for obtaining covalently crosslinked hydrogels and provides effective control on the structure of hydrogels spatially and temporally. Since UV light can cause cell damage, the power density and duration of UV to which cells are exposed must be optimized for bioprinting and adapted to the system. In situ crosslinking is critical in photopolymerization-based bioprinting processes, and designing bioprinting systems in this way is crucial for cell viability and print accuracy. Another important issue for 3D Bioprinters is that printing takes place under sterile conditions. Although the bioinks used are prepared under aseptic conditions, a sterile environment is required during printing. The commonly used method is to sterilize the 3D Bioprinter with alcohol and UV, and then place the bioprinting process in a sterile cabinet. However, this takes time and hinders the workflow in busy laboratories. The aim of the study is to develop a sterilizable, low-cost 3D bioprinter with adjustable position, power density and exposure time UV source by a unique extruder head design for in situ bioprinting.