Affordable, high-resolution bioprinting with embedded concentration gradients
Edwin Shen, Kara E. McCloskey
Abstract
Three-dimensional (3D) bioprinting has brought major innovations to the field in its ability to fabricate cell-laden constructs that closely resemble physiological tissue. Unfortunately, many bioprinters print only one material and at limited resolutions. Improving on the resolutions, functionality, and affordability necessitates attention to both printing techniques and printers. Here, we present our results towards building an affordable, partially open-source bioprinter, ModiPrint, that enables multiple cell-material combination printing with high resolution extrusions (100 μm) of alginate. We also introduce a new technique to improve extrusion resolution in complex geometries. The results show that we were able to maintain viability of human pluripotent stem cells (hiPSCs) after high resolution printing. Lastly, we were able to generate concentration gradients of small molecules or cytokines embedded within hydrogels by combining extrusion and drop-on-demand bioprinting. We expect ModiPrint and the novel techniques in our study will assist other bioprinting researchers.