Dual-crosslinked methylcellulose hydrogels for 3D bioprinting applications

Area of Science:

• Biomaterials Science
• Tissue Engineering
• 3D Bioprinting

Background:

• Thermo-sensitive methylcellulose (MC) hydrogels are useful for biomedical applications but lack mechanical strength for 3D bioprinting.
• Poor mechanical properties limit the use of MC-based hydrogels in tissue engineering scaffolds.

Purpose of the Study:

• To synthesize a dual crosslinkable tyramine-modified MC (MC-Tyr) conjugate.
• To evaluate the mechanical properties, printability, and biocompatibility of MC-Tyr hydrogels for 3D bioprinting applications.
• To investigate the efficacy of dual crosslinking strategies using thermal and visible light-induced photocrosslinking.

Main Methods:

• A two-step synthesis was employed to prepare the tyramine-modified MC (MC-Tyr) conjugate.
• Dual crosslinking was achieved through a combination of thermal (reversible physical) and visible light-induced photocrosslinking (irreversible chemical).
• Biocompatible photoinitiators (riboflavin and riboflavin 5'-monophophate) were used for photocrosslinking, and their effects were compared.
• Printing parameters were optimized, and cell-laden MC-Tyr bioink was extruded into 3D constructs.

Main Results:

• The MC-Tyr conjugate formed a dual-crosslinked hydrogel with excellent mechanical properties and printability.
• Visible light exposure with photoinitiators facilitated photocrosslinking, enabling the formation of stable 3D hydrogel constructs with high resolution.
• MC-Tyr scaffolds demonstrated excellent cell viability and proliferation, indicating good biocompatibility.

Conclusions:

• The dual crosslinking strategy using MC-Tyr conjugate significantly enhances mechanical properties and printability for 3D bioprinting.
• MC-Tyr hydrogels are promising biomaterials for fabricating tissue engineering scaffolds with improved structural integrity and biological performance.
• This approach overcomes the limitations of traditional MC hydrogels, opening new avenues for advanced tissue regeneration applications.