Interaction energies of mixing phosphatidylserine and phosphatidylcholine monolayers

The interactions between phosphatidylcholine and phosphatidylserine spread in monolayers of different molecular composition were studied. The influence in these mixtures of Na⁺ and Ca²⁺ ions was also determined. By applying the Goodrich, and Pagano and Gershfeld equations, the mixing energies and interactions at intermediate and collapse pressures were calculated. The maximum interaction occurs at higher pressures and in the presence of Ca²⁺ ions.