Chapter 6 - Theoretical methods for the optimization of 3D bioprinting: printability, formability, and cell survival

Abstract

The success of bioprinting hinges on multiple printing parameters. Therefore, mathematical and computational models are being developed to ensure a desirable outcome without costly trial-and-error experiments. Such models are the topic of this chapter. Furthermore, several examples are given to demonstrate that a quantitative approach is necessary even for the definition of successful bioprinting. First, basic notions of bioink rheology are presented and the dynamics of bioink extrusion is described. It is shown that, especially in the proximity of the nozzle wall, extruded cells suffer from prolonged exposure to high shear stress. Quantitative measures of bioink printability are also presented in the context of extrusion-based bioprinting. Then, droplet-based bioprinting is discussed with special attention given to mechanical factors that might affect cell viability. Finally, physicochemical factors involved in photopolymerization-based bioprinting are analyzed theoretically, and the predictions of the theoretical models are tested against experimental results obtained using stereolithography and digital light processing.