From simple surface models to lipid membranes: Universal aspects of the hydration interaction from solvent-explicit simulations

A review of atomistic simulation approaches including explicit water for the study of hydration forces between polar surfaces is presented. In particular, we discuss different methods for keeping the chemical potential of water constant and compare advantages and limitations of each method. It turns out that modifications of hydration forces due to surface softness can be accounted for by a convolution over the surface shape profile. Universal aspects of the hydration interaction observed in simulations of different surface chemistries are highlighted, while special attention is given to hydration forces between self-assembled phospholipid membranes.

Force-distance curves between phospholipid membranes computed in molecular dynamics simulations using explicit water molecules and a Thermodynamic Extrapolation method show remarkable agreement with classical swelling experiments. Figure optionsDownload high-quality image (239 K)Download as PowerPoint slideResearch Highlights
► Constant chemical potential of water is crucial for hydration interaction.
► Thermodynamic Extrapolation allows for efficient simulation of interacting surfaces.
► Surface rigidity influences hydration pressure in a predictable fashion.
► Hydration pressure is universal for different surface chemistries.