Application of classical nucleation theory to the formation of adhesion domains

Abstract

Specific adhesion of membranes proceeds through the formation of discrete bonds, the interactions of which are strongly influenced by thermal membrane undulations. Here we study the applicability of classical nucleation theory to the formation of adhesion domains of an initially unbound membrane. By employing high precision Monte Carlo simulations for a minimal model, we obtain the free energy of an adhesion domain in the background of the unbound membrane. We find that the free energy as a function of the cluster size is well described by the corresponding expression from classical nucleation theory with the line tension as a free parameter. We determine a simple but exact relationship for the line tension of an adhesion domain that should be useful in order to provide an estimate of critical sizes and nucleation barriers in realistic situations.