Cation-π Interaction Trigger Supramolecular Hydrogelation of Peptide Amphiphiles

Area of Science:

• Supramolecular Chemistry
• Biomaterials Science
• Chemical Biology

Background:

• Cation-π interactions are crucial noncovalent forces in biological and chemical systems.
• Their role in protein stability and molecular recognition is well-established.
• However, their application in driving supramolecular hydrogel formation remains unexplored.

Purpose of the Study:

• To investigate cation-π interactions as a primary driving force for self-assembling peptide amphiphiles into hydrogels.
• To explore the impact of cation-π interactions on peptide folding, hydrogel morphology, and mechanical properties.
• To assess the potential of these novel hydrogels for therapeutic applications, specifically protein delivery.

Main Methods:

• Design and synthesis of peptide amphiphiles incorporating cation-π interaction pairs.
• Characterization of self-assembly behavior under physiological conditions.
• Evaluation of peptide folding propensity using computational and experimental techniques.
• Assessment of hydrogel properties (morphology, rigidity) via microscopy and mechanical testing.
• In vitro studies to determine the efficacy of cytosolic protein delivery.

Main Results:

• Peptide amphiphiles successfully self-assembled into fibril-rich supramolecular hydrogels driven by cation-π interactions.
• Cation-π interactions were confirmed as a significant factor promoting peptide folding into β-hairpin structures.
• The resulting hydrogels exhibited tunable morphology and rigidity.
• The designed peptide hydrogels demonstrated high efficiency in delivering proteins into the cytosol.

Conclusions:

• Cation-π interactions can effectively drive the self-assembly of peptides into functional supramolecular hydrogels.
• This study presents the first instance of utilizing cation-π interactions for hydrogelation, offering a new strategy for biomaterial development.
• The developed hydrogels show promise as advanced platforms for cytosolic protein delivery.