An Underwater Surface-Drying Peptide Inspired by a Mussel Adhesive Protein

Area of Science:

• Biomaterials Science
• Adhesion Science
• Polymer Chemistry

Background:

• Water interferes with adhesive bonding to surfaces, limiting applications in wet environments.
• Mussel adhesive proteins provide a natural model for strong underwater adhesion.
• Developing synthetic analogues of mussel proteins is key for advanced adhesives.

Purpose of the Study:

• To design and synthesize a mussel foot protein homologue (mfp3S-pep) mimicking native protein properties.
• To investigate the role of 3,4-dihydroxy-l-phenylalanine (Dopa) in peptide adsorption and water displacement.
• To evaluate the adhesive potential of Dopa-functionalized peptides and their coacervates on wet surfaces.

Main Methods:

• Peptide synthesis and characterization to mimic mussel protein properties.
• Quartz crystal microbalance (QCM) and attenuated total reflection infrared spectroscopy (ATR-IR) for adsorption analysis.
• Contact angle measurements and water displacement assays to assess surface interactions.

Main Results:

• The synthetic peptide (mfp3S-pep) self-coacervates, similar to native mussel proteins.
• Dopa is essential for irreversible peptide adsorption onto titanium dioxide (TiO2) and hydroxyapatite (HAP) surfaces.
• Dopa-containing peptides displace interfacial water, with coacervates showing superior water removal and adhesion.

Conclusions:

• Dopa-functionalized peptides, particularly in coacervated form, demonstrate effective adhesion on wet polar surfaces.
• The study highlights the potential of bio-inspired Dopa chemistry for creating robust underwater adhesives.
• Findings pave the way for novel adhesive formulations for challenging biomedical and marine environments.