Jetting-based bioprinting: process, dispense physics, and applications

Jetting-based bioprinting facilitates contactless drop-on-demand deposition of subnanoliter droplets at well-defined positions to control the spatial arrangement of cells, growth factors, drugs, and biomaterials in a highly automated layer-by-layer fabrication approach. Due to its immense versatility, jetting-based bioprinting has been used for various applications, including tissue engineering and regenerative medicine, wound healing, and drug development. A lack of in-depth understanding exists in the processes that occur during jetting-based bioprinting. This review paper will comprehensively discuss the physical considerations for bioinks and printing conditions used in jetting-based bioprinting. We first present an overview of different jetting-based bioprinting techniques such as inkjet bioprinting, laser-induced forward transfer bioprinting, electrohydrodynamic jet bioprinting, acoustic bioprinting and microvalve bioprinting. Next, we provide an in-depth discussion of various considerations for bioink formulation relating to cell deposition, print chamber design, droplet formation and droplet impact. Finally, we highlight recent accomplishments in jetting-based bioprinting. We present the advantages and challenges of each method, discuss considerations relating to cell viability and protein stability, and conclude by providing insights into future directions of jetting-based bioprinting.

Graphic abstract