Pore formation and area exchange in tense membranes

Department of Materials and Interfaces, The Weizmann Institute of Science, Rehovot 76100, Israel

Received: 5 January 1998
Accepted: 14 May 1998

Abstract

We discuss the properties of fluid membranes, whose fluctuations are restricted due to lack of area. The additional free-energy cost of the difference between the actual and optimum areas of the membrane is derived, and two ways in which the membrane can lower this free-energy cost are discussed. Firstly, it is shown that the area dependence of the surface tension can surprisingly lead to a stable hole of finite size in the membrane. We then discuss the surface-tension–driven exchange between two membranes, and conclude that this process is likely to be observed between a tense and a fluctuating membrane. The relevance of these results for recent observations on systems of vesicles is briefly discussed.