Daniel Cole

Water structuring and collagen adsorption at hydrophilic and hydrophobic silicon surfaces

Daniel J. Cole,1 Mike C. Payne,1 Lucio Colombi Ciacchi2,3

1Theory of Condensed Matter Group, Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, UK
4Hybrid Materials Interfaces Group, Faculty of Production Engineering and Bremen Centre for Computational Materials Science, University of Bremen, 28359 Bremen, Germany
5Fraunhofer Institut für Fertigungstechnik und Angewandte Materialforschung IFAM, Wiener Str. 12, 28359 Bremen, Germany

The adsorption of a collagen fragment on both a hydrophobic, hydrogen-terminated and a hydrophilic, natively oxidised Si surface is investigated using all-atom molecular dynamics. While favourable direct protein-surface interactions via localised contact points characterise adhesion to the hydrophilic surface, evenly spread surface/molecule contacts and stabilisation of the helical structure occurs upon adsorption on the hydrophobic surface. In the latter case, we find that adhesion is accompanied by a mutual fit between the hydrophilic/hydrophobic pattern within the protein and the layered water structure at the solid/liquid interface, which may provide an additional driving force to the classic hydrophobic effect.

Phys. Chem. Chem. Phys. 11, 11395 (2009)