On the molecular basis of fouling resistance

This paper presents a review of models used to describe the properties of fouling resistant surfaces, i.e. the relationship between molecular structure and resistance to adsorption/adhesion of biological moieties. In particular, the well established 'physical' school of thought, mostly based on ideas stemming from the Alexander--De Gennes theory of polymer interfaces, which appears especially suitable for the modeling of resistance to bio-adhesion in terms of entropic effects, is compared to approaches that call into play the role of interfacial forces based on hydrogen bonding and molecular conformations. It is underlined that the presently prevailing view based on 'steric' stabilization effects is based on models that do not take into account some of the most fundamental aspects of water-soluble polymers and that, within this approximation, repulsive forces resulting from the 'compression' of tethered layers is the only possible explanation. When effects typical of water, such as hydrogen bonding, are considered, different pictures arise, even if their quantification poses several analytical challenges and new theoretical problems.