Recent decades have witnessed a growing demand for biologically inspired, water-resistant adhesives for applications such as dental and medical transplants and coronary artery coatings. Research in this area has focused on mussels, which form strong, water-resistant bonds to various underwater surfaces.

To advance the development of next-generation wet adhesives, researchers combined an experimental approach with theoretical modeling to examine the molecular basis of the gluelike properties of mussel foot proteins. The authors mounted two opposing surfaces in a custom-designed instrument and filled the thin gap between the two surfaces with a solution containing a synthetic peptide derived from mussel foot proteins, namely the MFP-3s peptide.

During the approach and separation of the surfaces from one another, the instrument measured the interaction forces between the surfaces as a function of distance, at the nanometer length scale. The MFP-3s peptides exhibited strong adhesion forces between hydrophobic surfaces, but weak adhesion forces between hydrophilic surfaces.

Simulations revealed the molecular origin of this difference in adhesion. According to the authors, analysis of the molecular interactions that enhance the stickiness of mussel foot proteins could lay the foundation for the development of water-resistant glues for a range of biomedical applications. 

http://www.pnas.org/content/early/2016/03/25/1603065113