3D Inkjet Printing of Complex, Cell-Laden Hydrogel Structures

Inkjet printing is widely considered a promising strategy to pattern hydrogels and living cells into three-dimensional (3D) constructs that structurally resemble tissues in our body. However, this approach is currently constrained by the limited control over multi-component deposition: the variable droplet ejection characteristics of different bioinks and dispensing units make synchronized printing very challenging. This invariably results in artificial tissues that lack the complexity and function of their native counterparts. By careful optimization of the printing parameters for two different bioink formulations, here we report the inkjet-based 3D-patterning of hydrogels according to relatively complex blueprints. 3D printing of bioinks containing living cells resulted in high-resolution, multi-component living constructs. Finally, we describe a sacrificial material approach to inkjet print perfuseable channels for improved long-term cultures of larger samples. We believe that this work provides a foundation for the generation of more complex 3D tissue models by inkjet printing.