How Surface Fluidity Impacts the Mechanics of Biofilm Adhesion*

Biofilm communities are notoriously difficult to eliminate once they have adhered to a surface. One approach to suppress biofilm adhesion is to vary the physical properties of the interface, such as the hydrophobicity, charge, or roughness. In this study we explore whether tuning the fluidity of a surface prevents bacterial adhesion by minimizing mechanical cues, thereby blocking the transition from the planktonic bacteria state to the biofilm state. To approach this question, we use a tunable, ultra-thick polymer brush comprised of the polymer hyaluronan. Unlike most polymer brushes used in antimicrobial interfaces, the extraordinary thickness and hence softness of these brushes confers them with fluid-like properties. We will present results on the dependence of biofilm formation versus the brush height ranging from 500 nm to 10 μm. We will then introduce crosslinking methods to tune the brush mechanics, and examine how loss of the brush fluidity and increasing stiffness impacts bacteria adhesion. This study should facilitate insight into the role of surface fluidity in preventing biofilm adhesion, and potentially provide a roadmap for the development of a new class of anti-microbial surface coatings.