Leveraging Protein-Ligand and DNA Interactions to Control Hydrogel Mechanics.

Area of Science:

• Biomaterials Science
• Supramolecular Chemistry
• Biotechnology

Background:

• Biomacromolecules are key building blocks for hydrogels, influencing material properties through their chemical identity and interactions.
• Current hydrogel development often relies on precise control over molecular components and their assembly.

Purpose of the Study:

• To introduce novel biomolecular hydrogels utilizing ligand-functionalized DNA and protein-ligand interactions.
• To demonstrate independent modulation of hydrogel properties by controlling DNA structure and protein-ligand binding affinities.

Main Methods:

• Fabrication of hydrogels with DNA backbones and protein-ligand cross-links.
• Tuning hydrogel stiffness, stress relaxation, and shear thinning by varying DNA rigidity (single-stranded vs. double-stranded) and protein-ligand binding affinities.
• Assessment of hydrogel cytocompatibility and cell-mediated degradation.

Main Results:

• Double-stranded DNA networks exhibited significantly higher stiffness (up to 3 orders of magnitude) and thermoresponsiveness compared to single-stranded networks.
• Protein-ligand binding affinities and dissociation rates were found to dictate network topology and stress relaxation dynamics.
• The developed hydrogels demonstrated cytocompatibility and facilitated cell migration through ligand-receptor interactions, enabling cell-type-specific degradation.

Conclusions:

• Varying local chemical interactions in the hydrogel backbone and supramolecular binding affinity of cross-links allows for precise control over viscoelastic properties.
• These cytocompatible hydrogels offer tunable mechanical characteristics for advanced applications in drug delivery and tissue engineering.