Simple peptide coacervates adapted for rapid pressure-sensitive wet adhesion

Area of Science:

• Biomaterials Science
• Adhesion Science
• Protein Engineering

Background:

• Mussel foot proteins are known for strong underwater adhesion.
• Existing synthetic mimics often require post-deposition processing for optimal performance.

Purpose of the Study:

• To investigate the underwater adhesive properties of a single mussel foot protein-3S-mimicking peptide coacervate.
• To explore the potential of coacervates as a design principle for advanced underwater adhesives.

Main Methods:

• Simple coacervation of a mussel foot protein-3S-mimicking peptide.
• Deposition and compression of the coacervate on underwater surfaces.
• Measurement of underwater adhesion strength and rheological properties.

Main Results:

• A structurally homogeneous coacervate liquid was formed and deposited as micrometer-thick layers.
• Compressed coacervate exhibited significantly higher underwater adhesion (2 N m^-1) compared to existing synthetic mimics.
• Adhesion was an intrinsic property, not requiring post-deposition curing or chemical processing.

Conclusions:

• Dense coacervate liquids of single peptides possess critical properties for underwater adhesion.
• These findings suggest a new design principle for synthetic underwater adhesives inspired by mussel adhesive strategies.
• The coacervate's properties are linked to dehydration, tight packing, and restricted peptide mobility.