3D double-reinforced graphene oxide - nanocellulose biomaterial inks for tissue engineered constructs.

The advent of improved fabrication technologies, particularly 3D printing, has enabled the engineering of bone tissue for patient-specific healing and the fabrication of in vitro tissue models for ex vivo testing. However, inks made from natural polymers often fall short in terms of mechanical strength, stability, and the induction of osteogenesis. Our research focused on developing novel printable formulations using a gelatin/pectin polymeric matrix that integrate synergistic reinforcement components i.e. graphene oxide (GO) and oxidized nanocellulose fibers (CNF). Using 3D printing technology and the aforementioned biomaterial composite inks, bone-like scaffolds were created. To simulate critical-sized flaws and demonstrate scaffold fidelity, 3D scaffolds were successfully printed using formulations with varied GO concentrations (0.25, 0.5, and 1% wt with respect to polymer content). The addition of GO to hydrogel inks enhanced not only the compressive modulus but also the printability and scaffold fidelity compared to the pure colloid-gelatin/pectin system. Due to its strong potential for 3D bioprinting, the sample containing 0.5% GO is shown to have the greatest perspectives for bone tissue models and tissue engineering applications.