Three-Dimensional Bioprinting of Cell-Laden Constructs Using Polysaccharide-Based Self-Healing Hydrogels

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• 3D printing requires advanced bioinks for tissue and organ regeneration.
• Limited availability of printable biomaterials hinders progress in 3D bioprinting applications.
• Controlling bioink rheology and printed construct mechanics is crucial for practical use.

Purpose of the Study:

• To design and develop a novel, printable, self-healing hydrogel bioink.
• To explore its potential for cartilage regeneration using tissue engineering approaches.
• To investigate the influence of polymer parameters on hydrogel properties.

Main Methods:

• Prepared self-healing hydrogels using partially oxidized hyaluronate (OHA) and glycol chitosan (GC) with adipic acid dihydrazide (ADH).
• Utilized dynamic imine and acylhydrazone bonds for intrinsic self-healing properties.
• Fabricated 3D constructs using an extrusion-based 3D printer without post-gelation crosslinking.

Main Results:

• The OHA/GC/ADH hydrogels exhibited self-healing capabilities due to dynamic covalent bonds.
• Hydrogel properties were tunable by adjusting polymer concentrations and molecular weights.
• 3D printed, cell-laden constructs maintained ATDC5 cell viability and chondrogenic gene expression (SOX-9, collagen type II).

Conclusions:

• A novel self-healing hydrogel bioink was successfully developed for 3D bioprinting.
• The OHA/GC/ADH system demonstrates significant potential for cartilage tissue engineering.
• The bioink is suitable for fabricating cell-laden constructs with preserved cellular function.