3D Bioprinting Using\nUniversal Fugitive Network Bioinks

Three-dimensional (3D) bioprinting has emerged with potential\nfor\ncreating functional 3D tissues with customized geometries. However,\nthe limited availability of bioinks capable of printing 3D structures\nwith both high-shape fidelity and desired biological environments\nfor encapsulated cells remains a key challenge. Here, we present a\n3D bioprinting approach that uses universal fugitive network bioinks\nprepared by loading cells and hydrogel precursors (bioink base materials)\ninto a 3D printable fugitive carrier. This approach constructs 3D\nstructures of cell-encapsulated hydrogels by printing 3D structures\nusing fugitive network bioinks, followed by cross-linking printed\nstructures and removing the carrier from them. The use of the fugitive\ncarrier decouples the 3D printability of bioinks from the material\nproperties of bioink base materials, making this approach readily\napplicable to a range of hydrogel systems. The decoupling also enables\nthe design of bioinks for the biological functionality of the final\nprinted constructs without compromising the 3D printability. We demonstrate\nthe generalizable 3D printability by printing self-supporting 3D structures\nof various hydrogels, including conventionally non-3D printable hydrogels\nand those with a low polymer content. We conduct preprinting screening\nof bioink base materials through 3D cell culture to select bioinks\nwith high cell compatibility. The selected bioinks produce 3D constructs\nof cell-encapsulated hydrogels with both high-shape fidelity and high\ncell viability and proliferation. The universal fugitive network bioink\nplatform could significantly expand 3D printable bioinks with customizable\nbiological functionalities and the adoption of 3D bioprinting in diverse\nresearch and applied settings.