Possible mechanism of adhesion in a mica supported phospholipid bilayer.

Phospholipid bilayers supported on hydrophilic solids like silica and mica play a substantial role in fundamental studies and technological applications of phospholipid membranes. In both cases the molecular mechanism of adhesion between the bilayer and the support is of primary interest. Since the possibilities of experimental methods in this specific area are rather limited, the methods of computer simulation acquire great importance.

Computer simulation of water-mediated adhesion between phospholipid bilayer and solid support functionalized with self-assembled monolayers.

An attempt is made to estimate, via computer simulation of the force-distance relation, the free energy of adhesion between a phosphatidylethanolamine bilayer and an alkanethiolate self-assembled monolayer (SAM) in aqueous medium. The simulations are performed using the grand canonical Monte Carlo technique and atomistic force fields. The bilayer adhesion free energy is predicted to be -22 ± 3 mJ/m(2) (-1.

Computer simulation of adhesion between hydrophilic and hydrophobic self-assembled monolayers in water.

The grand canonical Monte Carlo technique and atomistic force fields are used to calculate the force-distance relations and free energies of adhesion between carboxyl and methyl terminated alkanethiolate self-assembled monolayers (SAMs) in water. Both symmetric and asymmetric confinements are considered, as formed by like and unlike SAMs, respectively. As the confinement is increased, water confined by the hydrophobic methyl terminated SAMs experiences capillary evaporation.

Quasistatic computer simulations of shear behavior of water nanoconfined between mica surfaces.

We combine the grand canonical Monte Carlo and molecular dynamics techniques to simulate the shear response of water under a 9.2 Å confinement between two parallel sheets of muscovite mica. The shear deformation is modeled in the quasistatic regime corresponding to an infinitely small shear rate.

Computer simulation of water-mediated forces between gel-phase phospholipid bilayers.

Water-mediated forces between gel-phase phospholipid bilayers were calculated as a function of interbilayer separation using the grand canonical Monte Carlo technique and all-atom CHARMM force field. The mechanism of the short-range interbilayer repulsion proved to be similar to that calculated previously for the fluid-phase bilayers despite substantial differences in structure and areal density between the gel and fluid phases.

Quasistatic computer simulation study of the shear behavior of Bi- and trilayer water films confined between model hydrophilic surfaces.

In this paper, our previous simulations of the shear behavior of confined water monolayers (Pertsin, A.; Grunze, M. Langmuir 2008, 24, 135) are extended to water films two and three monolayers thick.

A computer simulation study of stick-slip transitions in water films confined between model hydrophilic surfaces. 1. Monolayer films.

The shear behavior of monolayer water films confined in a slit-like pore between hydrophilic walls is simulated in the quasistatic regime using the grand canonical Monte Carlo technique. Each wall is represented as a hexagonal lattice of force sites that interact with water through an orientation-dependent hydrogen-bonding potential. When the walls are in registry, the water oxygen atoms form either a crystal- or fluid-like structure, depending on the period of the wall's lattice.

Temperature dependence of the short-range repulsion between hydrated phospholipid membranes: A computer simulation study.

The temperature dependence of the short-range water-mediated repulsive pressure between supported phospholipid membranes is calculated at two intermembrane separations using the grand canonical Monte Carlo technique. At both separations, the simulated pressure tends to decrease with temperature, in qualitative agreement with the experimental measurements by Simon and co-workers [Simon et al., Biophys.

Origin of short-range repulsion between hydrated phospholipid bilayers: a computer simulation study.

The grand canonical Monte Carlo technique is used to simulate the pressure-distance dependence for supported dilauroylphosphatidylethanolamine (DLPE) membranes. The intra- and intermolecular interactions in the system are described with a combination of an AMBER-based force field for DLPE and a TIP4P model for water. To improve the balance between the pair interactions of like and unlike molecules, the water-lipid interaction potentials are scaled to reproduce the hydration level and intermembrane separation at full hydration.

Water as a lubricant for graphite: a computer simulation study.

The phase state and shear behavior of water confined between parallel graphite sheets are studied using the grand canonical Monte Carlo technique and TIP4P model for water. In describing the water-graphite interaction, two orientation-dependent potentials are tried. Both potentials are fitted to many-body polarizable model predictions for the binding energy and the equilibrium conformation of the water-graphite complex [K.

Computer simulation of short-range repulsion between supported phospholipid membranes.

The grand canonical Monte Carlo technique is used to calculate the water-mediated pressure between two supported 1,2-dilauroyl-DL-phosphatidylethanolamine (DLPE) membranes in the short separation range. The intra- and intermolecular interactions in the system are described with a combination of a united-atom AMBER-based force field for DLPE and a TIP4P model for water. The total pressure is analyzed in terms of its hydration component and the component due to the direct interaction between the membranes.

Direct computer simulation of water-mediated force between supported phospholipid membranes.

The grand canonical Monte Carlo technique is used to calculate the water-mediated force operating between two supported 1,2-dilauroyl-DL-phosphatidylethanolamine (DLPE) membranes in the short separation range. The intra- and intermolecular interactions in the system are described with a combination of an AMBER-based force field for DLPE and a TIP4P model for water. The long range contributions to the electrostatic interaction energy are treated in the dipole-dipole group-based approximation.