abstract
- Shear-thinning bioinks formulated by a suspension of synthetic nanosilicates in water were employed for bioprinting. The 5% nanosilicate bioink was chosen as the optimal formulation that possessed proper shear-thinning properties, and was thus used to bioprint various 3D constructs. The bioprinting process was continuous, and the printed microfibrous structure maintained its three-dimensionality consisting of an array of spatially well-defined bioinks. The seven bioinks could also be individually deposited via a continuous printing process where no noticeable switching delays were observed between adjacent materials. A series of microfibrous 2D patterns were printed to demonstrate the capability of our bioprinter for continuous extrusion of multiple materials in well-defined manners. Alternatively, the spacing between the adjacent microfibers could be maintained constant while continuous segments within individual lines were printed with decreasing lengths or both parameters might be altered simultaneously during the bioprinting process. The printed microfibers joined each other and formed a cohesive piece of monolayer slab containing seven distinct but continuous segments along the direction of microfiber deposition. This ability to create fused larger-scale constructs allowed us to print more sophisticated patterns composed of multiple bioinks, which has hardly been possible using existing multiprinthead systems. It is estimated that the continuous multimaterial bioprinter features much faster fabrication speed than most existing multinozzle systems.