Water structuring and collagen adsorption at hydrophilic and hydrophobic silicon surfaces

TL;DR

This study uses molecular dynamics to compare collagen fragment adsorption on hydrophilic and hydrophobic silicon surfaces, revealing different interaction mechanisms and the role of water structuring in adhesion.

Contribution

It provides detailed molecular insights into collagen-silicon interactions, highlighting the influence of surface chemistry and water structure on protein adsorption.

Findings

Hydrophilic surface shows localized contact points and stabilizes helical structure.

Hydrophobic surface promotes even contact distribution and water-mediated adhesion.

Water layering at the interface influences the adhesion mechanism.

Abstract

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.