In situ effect of printing parameters on microstructural anisotropy of bioink based hydrogel during micro-extrusion bioprinting process for

Bioprinting is a promising process to provide hospitals with tissue substitutes mimicking any organ without having to resort to donors. During bioprinting, a cell-encapsulating hydrogel, also known as bioink, is deposited layer by layer to ultimately develop a tissue substitute. An alginate/gelatine/fibrinogen hydrogel will be used for its shear thinning properties, biocompatibility, bioresorbability and shape fidelity after printing. Due to printing, polymer macromolecules composing the hydrogel have a local orientation inducing anisotropic mechanical properties in the printed object. Printing parameters have an effect on this anisotropic microstructure but the phenomenon is not yet controlled in the bioprinting process. Thus, the novelty of this proposal is to study this phenomenon using the in situ Small-Angle (SAXS) and Wide-Angle X-ray Scattering (WAXS) scanning approach to visualise the orientation of hydrogel macromolecules during extrusion.