A Simple Methodology for Determining Optimal Print Parameters for 3D Bioprinting with Low-viscosity Bioink

Abstract

Animal models are often used to study disease, but these models are limited because they often fail to represent human anatomy and disease-state characteristics. Recently, 3D bioprinting has been employed to construct customizable and complex cell-laden tissue structures, which have the potential to complement or replace these animal models with patient-specific anatomies and disease states. Some challenges of 3D bioprinting include the use of a low-viscosity bioink, and the imposition of shear stress on cells during extrusion. The lack of quantification and optimization of 3D printing parameters with this ink-type make the generation of high-resolution, reproducible prints difficult.

            In this study, a methodology was developed to quantify both the print fidelity and resolution associated with various print parameters, which was used to select a set of optimized 3D bioprinting parameters for a gelatin methacrylate (GelMA)-based bioink. The best conditions for fidelity and resolution were a print speed of 14 mm/s at a flow rate of 1 drop/4s and a print speed of 12 mm/s at a flow rate of 1 drop/4s, and the worst condition for both the fidelity and resolution was a print speed of 10 mm/s at a flow rate of 1 drop/2s. These results will inform future work, which will optimize the resolution, fidelity, and cell viability and determine an optimal set of conditions for 3D printing a cardiac organoid.