Hyaluronic acid single-network hydrogel with high stretchable and elastic properties

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Tissue Engineering

Background:

• Stretchable materials are crucial for wearable and implantable devices.
• Existing hydrogels often lack elasticity, exhibit hysteresis, and suffer permanent rupture.
• Elastic, biodegradable hydrogels are needed for wound healing in mobile tissues.

Purpose of the Study:

• To develop a simple method for creating a stretchable and highly elastic hyaluronic acid (HA) single-network hydrogel.
• To investigate the role of high molecular weight HA and covalent cross-links in achieving desired material properties.
• To assess the recovery and hysteresis behavior of the developed hydrogel.

Main Methods:

• Preparation of a single-network hydrogel using high molecular weight hyaluronic acid (HA).
• Incorporation of a small number of covalent cross-links to stabilize the entangled HA network.
• Characterization of hydrogel stretchability, elasticity, hysteresis, and recovery through stretching-relaxation cycles.

Main Results:

• A simple strategy yielded a stretchable and highly elastic HA single-network hydrogel without complex additives.
• Densely entangled HA chains, stabilized by covalent bonds, enabled high stretchability and tension transmission.
• The hydrogel demonstrated negligible hysteresis and perfect recovery after stretching-relaxation cycles.
• Reduced molecular weight or increased cross-linker concentration resulted in brittle hydrogels.

Conclusions:

• The developed HA hydrogel offers a promising alternative to existing stretchable materials for biomedical applications.
• The strategy provides a facile route to engineer elastic and recoverable hydrogels from high molecular weight HA.
• This research paves the way for advanced wound dressings and soft electronics.