Peptide Amphiphile Hydrogels Based on Homoternary Cucurbit[8]uril Host-Guest Complexes

Area of Science:

• Biomaterials Science
• Supramolecular Chemistry
• Tissue Engineering

Background:

• Peptide amphiphile (PA) hydrogels are vital for tissue engineering and modeling extracellular matrices.
• Conventional PA hydrogel formation relies on electrostatic screening, limiting design versatility.
• Novel hydrogelation mechanisms are needed to enhance PA material functionality.

Purpose of the Study:

• To introduce a new host-guest-mediated hydrogelation method for peptide amphiphiles (PAs).
• To investigate the impact of cucurbit[8]uril (CB[8]) cross-linking on PA hydrogel morphology and properties.
• To compare the performance and biocompatibility of CB[8]-mediated PA hydrogels with ion-based hydrogels.

Main Methods:

• Utilized a host-guest complexation strategy involving cucurbit[8]uril (CB[8]) and aromatic amino-acid-bearing PA nanofibers.
• Formed supramolecular hydrogels through CB[8]-mediated cross-linking of PA nanofibers.
• Characterized the hierarchical morphologies and mechanical stiffness of the resulting hydrogels.
• Assessed the biocompatibility of both host-guest and ion-based PA hydrogels.

Main Results:

• CB[8]-mediated cross-linking resulted in hierarchical morphologies and increased stiffness compared to ion-based PA hydrogels.
• The host-guest approach demonstrated effective cross-linking of PA nanofibers.
• Both CB[8]-mediated and ion-based hydrogels exhibited comparable biocompatibility.
• The study successfully established CB[8] as a viable cross-linking agent for PA hydrogels.

Conclusions:

• Host-guest complexation with CB[8] provides an effective alternative cross-linking mechanism for peptide amphiphile hydrogels.
• This method enhances hydrogel hierarchical structure and mechanical properties, offering advantages over traditional methods.
• CB[8]-mediated hydrogelation expands the design possibilities for PA-based biomaterials in tissue engineering and biomedical applications.