Optimization of starch- and chitosan-based bio-inks for 3D bioprinting of scaffolds for neural cell growth

This paper investigates the use of starch and chitosan blends for bioprinting of neural cell applications. The printability and biocompatibility of different starch to chitosan ratio bio-inks were studied. The biofabrication window paradigm was used to determine the optimum composition of bio-ink as 50% starch and 50% chitosan in terms of both printability and biocompatibility with Neuro-2a cells. This defies the conventional understanding that increasing the chitosan percentage enhances the biocompatibility. Moreover, the limitations of the conventional framework for characterizing the printability of bio-inks were identified and a revised framework based on the flattening factor was proposed. It was shown that the revised framework provides better means of characterizing the printability of bio-inks.