Nanocellulose-based bio-inks for 3D bioprinting: advances and prospects in bone and cartilage tissue engineering

Tissue engineering offers promising regenerative alternatives to conventional medical treatments, particularly for tissues with limited self-healing capabilities such as bone and cartilage. Central to this field is three-dimensional (3D) bioprinting, an advanced fabrication technique that utilizes bio-inks to construct complex, patient-specific tissue structures. Among emerging bio-ink materials, nanocellulose and its derivatives have attracted considerable attention for their exceptional mechanical properties, biocompatibility, and biodegradability. Derived from natural cellulose, nanocellulose exists primarily as cellulose nanocrystals (CNCs) and cellulose nanofibers (CNFs), each contributing unique structural and rheological characteristics. CNCs enhance scaffold stiffness and mechanical strength, while CNFs support intricate architectures conducive to cellular infiltration and tissue growth. This review highlights recent advances in nanocellulose-based bio-inks for 3D bioprinting, emphasizing their role in improving printability and scaffold functionality for bone and cartilage tissue engineering applications.