【Original Contribution】Potential Interaction Behavior of Lanosterol and Unsaturated Phosphocholine in Monolayer Membrane

Abstract

Monolayers of lanosterol (Lan) and 1,2–dioleoyl–sn–glycero–3–phosphocholine (DOPC) were prepared at the air/water interface, to investigate potential interaction of Lan with unsaturated lipid. Excess area values of DOPC/Lan mixture were almost negative at pressures below 30 mN/m, while an increase of compression modulus was obtained at Lan ≧ 50 mol%. Excess Gibbs free energy analysis revealed a favorable interaction between DOPC and Lan at high concentration, which could be responsible to weak but sure ordering effect of Lan in unsaturated lipid bilayers.