The field of adhesives for biomedical applications is rapidly evolving, leading to tissue adhesives that combine strong adhesion to tissues with advanced functionality. Tissue adhesives, as compared to conventional suturing and tissue stapling, are easy to place in small spaces, shorten operating times and prevent tissue damage and scarring. Tissue adhesives are currently finding their way in a variety of medical settings such as wound closure, surgical sealants, regenerative medicine, and device attachment.
In this talk I will present recent developments in water-based pressure sensitive adhesives for biomedical applications. After a general overview, I will focus on our efforts mimicking the adhesive secretions of marine animals such as the sandcastle worm. Characteristic of the proteins found in the adhesive of sandcastle worms is a high proportion of cationic and anionic residues. These anionic and cationic residues are often said to be involved in a secondary interaction that aids cohesion, namely complex coacervation. This is an attractive phase separation of mixtures of polyanions and polycations that results in a highly polyelectrolyte-rich phase in equilibrium with almost pure solvent. Complex coacervates are mechanically well-suited for adhesive applications by controlling the amount of water. We aim to reproduce the working mechanism of sandcastle worms by developing a new class of underwater adhesives based on complex coacervates reinforced with physical interactions.