Development of 'Multi-arm Bioprinter' for hybrid biofabrication of tissue engineering constructs

This paper highlights the development of 'Multi-arm Bioprinter (MABP)' capable of concurrent multi-material deposition with independent motion path and dispensing parameters including deposition speed, material dispensing rate, and nozzle travel velocity for use in tissue engineering. In this research, the system is designed to concurrently print a filament structure and deposit cell spheroids between the filaments to create a hybrid structure to support the cell spheroids in three dimensions (3Ds). This process can be used with multiple cell types and is capable of reducing the fabrication time while using optimized dispensing parameters for each material. A novel method of dispensing the crosslinking solution using a co-axial nozzle was also developed and demonstrated in this paper. Cell-laden structures were fabricated through concurrent deposition of cell-encapsulated filaments and with cell spheroids to validate this concept. Rheology studies were then conducted to determine the effects of crosslink flow on filament width, hydrogel dispensing pressure on filament width, and dispensing time interval on spheroid diameter.