Three-dimensional (3D) printing is an emerging approach for rapid fabrication of complex tissue structures using cell-loaded bioinks. However, 3D bioprinting has hit a bottleneck in progress due to the lack of suitable bioinks that are printable, have high shape fidelity, and are mechanically resilient. In this study, we introduce a novel family of nanoengineered bioinks consisting of Kappa-Carrageenan (?CA) and nanosilicates (nSi). ?CA is a biocompatible linear sulfated polysaccharide derived from red algae and is able to undergo quick thermoreversible and ionic gelation. The shear-thinning characteristics of ?CA was modified by nanosilicates to develop a printable bioink. By tuning ?CA-nanosilicate ratios, the thermoreversible gelation of the bioink can be controlled to obtain high shape retention. The unique aspect of the nanoengineered ?CA-nSi bioink is its ability to print closer to physiologically relevant scale tissue constructs than conventional bioinks without requiring secondary supports. We envision that nanoengineered ?CA-nSi bioinks can be used to bioprint complex, large-scale, cell-laden tissue constructs with high structural fidelity and mechanical stiffness for applications in custom bioprinted scaffolds and tissue engineered implants.
