From supported membranes to tethered vesicles: Lipid bilayers destabilisation at the main transition

Institut Charles Sadron (UPR 22), CNRS-ULP - 6 rue Boussingault B.P. 40016 67083 Strasbourg Cedex, France

Received: 31 January 2006
Accepted: 21 June 2006

Abstract

We report results concerning the destabilisation of supported phospholipid bilayers in a well-defined geometry. When heating up supported phospholipid membranes deposited on highly hydrophilic glass slides from room temperature (i.e. with lipids in the gel phase), unbinding was observed around the main gel to fluid transition temperature of the lipids. It leads to the formation of relatively monodisperse vesicles, of which most remained tethered to the supported bilayer. We interpret these observations in terms of a sharp decrease of the bending rigidity modulus κ in the transition region, combined with a weak initial adhesion energy. On the basis of scaling arguments, we show that our experimental findings are consistent with this hypothesis.