Water Meniscus-Directed Organization of Liquid-Ordered Domains in Lipid Monolayer

Abstract

We report on a spatial organization process of liquid-ordered (l(o)) domains in a lipid monolayer into a two dimensional array on structurally patterned substrates. The curvature of a lipid monolayer which strongly obeys the water meniscus at an air-water interface is manipulated to create two different, curved and flat, zones during the water evaporation in the structural patterns. Due to the high bending rigidity, l(o) domains are diffused into the flat region to avoid the elastic deformation. The Helfrich-type thermodynamic criterion for coarsening of l(o) domains was first presented and confirmed through experimental results obtained in various patterns. Our topographic system will be very useful for understanding a fundamental concept as well as a quantitative criterion for curvature-driven organization of l(o) domains in biological membranes.