Dual extruder 3D-bioprinter for computer designed cardiac structures

A precise location of cells is of high interest for the characterization of cell interaction in in-vitro studies. Bioprinters can be a useful and automatized tool to produce these biological structures with precision. The objective of this study is to develop and validate a low-cost novel dual-extruder 3D bioprinter with enough resolution to study the electrophysiological interaction between different cell types. An open source classical 3D printer was adapted to incorporate two syringe extruders, allowing controlled delivery of hydrogel-cell ink. Four different parameters were studied to adjust precision: the needle lumen (G), the density of the hydrogel (%), the linear velocity of the extruder in the platform (mm/s) and the extrusion velocity (steps of the NEMA 17 extruder motor). Cell viability was tested with alamarBlue test and spatial distribution of cells was studied with fluorescence microscopy. As a result of this study, thin lines of 1.18 mm in width with 85% viability after 24h of printing process were obtained.