Studying three phase contact in the system air/DMPC water dispersion/silica

The studying of lipid vesicles is motivated because they are a useful model of biological membranes. The behavior of three phase contact (TPC) formed on different substrates from lipid dispersions is of high practical importance. In the present paper, we study wetting of hydrophilic silica surfaces with DMPC dispersion by measurement of their three-phase contact (TPC) parameters. These properties can provide more detailed information about the hydrophobicity and structure of the adsorbed lipid layer. The calculation of TPC parameters, from the contact angle and surface tension of liquid–vapor interface experimental data starts with Youngʹs equation. An approach of additional relation among the parameters of Youngʹs equation such as an equation-of-state relation is used to calculate the surface tensions solid–liquid and solid–vapor interfaces. Two states are observed distinctly in dependence of the phase interface surface tension on the DMPC dispersion concentration. The calculated values of the adsorption are reasonable. Surface adsorption at the solid–liquid interface is significantly lower than the adsorption of the other two interfaces. The obtained results about the adsorption are in agreement with the expected physical picture.