Cation-Pi Interaction-Mediated Wet Adhesive Inspired by Proteins in Marine Organisms
Jonathan Han
Burnaby North Secondary
Floor Location : S 061 N

Most adhesives which excel in dry settings are rendered ineffective in aqueous medium largely due to superficial hydration layers of fluids which impede electrostatic interactions. Recently, catechol-functionalized synthetic wet adhesives have been popular in literature, although these adhesives are less effective in saline environments and are susceptible to oxidation. These limitations especially hinder the feasibility of these adhesives in biomedical and marine applications; bodily fluids such as blood, sweat, and mucus, as well as seawater all contain high amounts of dissolved ions which prevent initial attachment of synthetic adhesives to substrates.

Marine organisms such as certain mollusks and arthropods have a remarkable ability to attach with robust strength to substrates while in saline, aqueous environments. Aspects of marine contact adhesion have been frequently translated to synthetic systems over the last decade, and recent investigations showed the cation-π interaction to be a possible contributor to adhesion in mussel foot proteins. In our investigations, we present an effective cation-π functionalized wet adhesive intended for biomedical and marine applications. An adhesive film consisting of copolymers of non-catecholic aromatic groups with negative, π terminals and positive, cationic terminals was optimized for adhesive strength on stainless steel in a saline solution using a PT-1000 Polyken “Probe Tack” machine. The optimized copolymer film drew tack values of ≅41N/cm2 in simulated bodily salinity, indicating significant viability. In addition, investigations were performed to characterize the nature of the cation-π interaction’s contribution to adhesiveness in the system.