Molecular arrangement in monolayers containing cholesterol and dipalmitoyl lecithin.

The molecular arrangement of dipalmitoyl lecithin and cholesterol in mixed monolayers was investigated with the aid of a physical model. The two lipids are miscible at the surface, but there is no indication of a specific interaction. In equimolar mixed monolayers at 25 and 37 degrees, the lipids are in tail contact. Lecithin molecules are able to remain hydrated in the mixed monolayers at high values of surface pressure.