Desmosine-inspired cross-linkers for hyaluronan hydrogels

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Tissue Engineering

Background:

• Natural elastin utilizes desmosine as a cross-linker, imparting unique mechanical properties to tissues.
• Developing synthetic hydrogels with similar resilience and tunable characteristics is crucial for biomedical applications.

Purpose of the Study:

• To design and synthesize bioinspired cross-linkers based on desmosine.
• To create semi-synthetic hydrogels using thiolated hyaluronic acid and these novel cross-linkers.
• To investigate the influence of cross-linker charge on hydrogel mechanical properties.

Main Methods:

• Synthesis of desmosine-based pyridinium salt cross-linkers.
• Preparation of hydrogels by cross-linking thiolated hyaluronic acid with the synthesized cross-linkers.
• Characterization of hydrogel mechanical properties, including stability, elasticity, and strain stiffening.
• Evaluation of the effect of introducing positive charge into the cross-linker core.

Main Results:

• The synthesized hydrogels are form-stable and exhibit mechanical robustness under repeated stress.
• The hydrogels display a large linear-elastic range and characteristic strain stiffening behavior.
• Introducing a positive charge to the cross-linker core did not impact gelation efficiency or network connectivity.
• Hydrogel mechanical properties were found to be strongly dependent on the charge of the cross-linker.

Conclusions:

• Bioinspired cross-linkers based on desmosine enable the creation of mechanically robust and tunable hydrogels.
• The charge of the cross-linker can be modulated to fine-tune hydrogel properties for soft tissue engineering.
• These semi-synthetic hydrogels represent a promising platform for developing advanced biomaterials.