Escherichia coli adhesion to surfaces–a thermodynamic assessment

Several studies have tried to correlate bacterial adhesion with the physicochemical properties of the surface with limited success. Most often, the obtained correlations seem to be only applicable to a particular set of experimental conditions making it difficult to obtain guidelines for the design of antibiofouling surfaces. The ratio between Lifshitz van der Waals apolar component and the electron donor component (γ^LW/γ⁻) was recently shown to correlate with bacterial adhesion to the surfaces of ship hulls and heat exchangers. In this work, four materials with biomedical application (polystyrene, poly-l-lactide, cellulose acetate, and polydimethylsiloxane) and glass were characterized and Escherichia coli adhesion to those materials was assayed with a parallel-plate flow chamber operating in physiological shear stress conditions. Adhesion was correlated with the γ^LW/γ⁻ ratio, further extending the application range tested on the original study. Additionally, results from other studies were also evaluated to confirm the applicability of this correlation to other surfaces, microorganisms, and experimental conditions. Results show that bacterial adhesion is reduced in surfaces with lower γ^LW/γ⁻and enhanced otherwise. This finding may be helpful in the design of new coatings by controlling γ^LW/γ⁻ or in the selection of existing materials according to the desired application.