Adhesion-induced reorganization of charged fluid membranes

Abstract
Adhesion between simple single-component membranes is both theoretically and experimentally well understood. We report on a combined theoretical and experimental study of the adhesion between well-characterized multicomponent membranes. In particular, we examined the statics and dynamics of the adhesion between a cationic vesicle and an anionic supported membrane on a substrate with a pH adjustable surface charge. Through interferometric methods, we measured the adhesion-induced membrane tension. We find a dramatic breakdown of the classical Young-Dupré law at higher surface charge densities. The failure of the Young-Dupré law is associated with the formation of blisters. These results are in agreement with a thermodynamic analysis of anion-cation adhesion which predicts that adhesion-induced phase separation leads to reorganization of the adhesion disk and to a failure of the Young-Dupré law. Our study demonstrates that adhesion of multicomponent membranes is fundamentally different from that of single-component membranes.