Visible light crosslinkable human hair keratin hydrogels

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Polymer Chemistry

Background:

• Keratins from human hair are attractive biomaterials due to availability, low cost, and minimal immune response.
• Current keratin scaffold fabrication methods are slow and yield limited mechanical strength and stability.
• Developing advanced crosslinking strategies is crucial for enhancing keratin-based biomaterial performance.

Purpose of the Study:

• To develop a rapid, photocrosslinkable keratin-based hydrogel system.
• To investigate the mechanical properties and stability of the novel hydrogels.
• To evaluate the cytocompatibility and potential for microfabrication of keratin-PEG hydrogels.

Main Methods:

• Photocrosslinkable keratin-polyethylene glycol (PEG) hydrogels were synthesized using a thiol-norbornene click reaction.
• Hydrogel mechanical properties were quantified by compressive modulus measurements.
• Cytocompatibility was assessed using fibroblast cell culture in 2D and 3D formats.
• Microfabrication techniques including micropatterning and wet spinning were explored.

Main Results:

• The keratin-PEG hydrogels were formed rapidly (within one minute) under visible light irradiation.
• Tunable mechanical properties were achieved, with compressive moduli up to 45 kPa.
• Hydrogels exhibited long-term stability in various solutions and supported fibroblast attachment, spreading, and proliferation.
• The photocrosslinking enabled fabrication of cell-laden constructs using micropatterning and wet spinning.

Conclusions:

• Photocrosslinkable keratin-PEG hydrogels offer a rapid and versatile platform for tissue engineering.
• The tunable mechanical properties and excellent cytocompatibility make them suitable for diverse biomedical applications.
• This approach facilitates advanced microfabrication techniques for creating complex, cell-laden tissue constructs.