Novel Bioinks from UV-Responsive Norbornene-Functionalized Carboxymethyl Cellulose Macromers

3D bioprinting has dramatically changed the field of tissue engineering and regenerative medicine by enabling biofabrication of living tissues in a more flexible, controlled, and customized manner. Although many hydrogels are available to formulate bioinks for bioprinting, researchers are still seeking bioinks with the flexibility of biochemical functionalization, stimuli responsiveness, and control over mechanical and degradation properties, to realize the full potential of bioprinting. Here, we report two novel bioink platforms from norbornene modified cellulose-based macromers: norbornene carboxymethyl cellulose and carbic functionalized carboxymethyl cellulose. Both of the bioink formulations could be crosslinked by either autogelation without light exposure, or rapid gelation via photoinitiated thiol-ene click chemistry under UV light. Bioink viscosity, printability, and the bioprinted construct’s mechanics are controlled by the macromer concentration and thiol to norbornene ratio. Multiple cell types were highly viable (~90%) within bioprinted constructs. The norbornene modified cellulose-based bioink platforms are economical and available for selectively tethering molecules or controlled crosslinking, which promise a potential towards 3D bioprinted complex constructs.