Effects of a pulling force on the shape of a bound vesicle

A.-S. Smith; E. Sackmann; U. Seifert

doi:doi:10.1209/epl/i2003-00499-9

DOI: 10.1209/epl/i2003-00499-9
Europhys. Lett., 64 (2) , pp. 281-287 (2003)

Effects of a pulling force on the shape of a bound vesicle

A.-S. Smith¹, E. Sackmann¹ and U. Seifert²

¹ Technische Universität München, E22 Institut für Biophysik D-85748 Garching, Germany
² Universität Stuttgart, II. Institut für Theoretische Physik D-70550 Stuttgart, Germany

(Received 20 May 2003; accepted in final form 4 August 2003)

Abstract
We develop a theoretical model to describe the vertical pulling of vesicles adhered in a contact potential. For a range of applied forces, locally stable bound shapes, separated from the free shape by an energy barrier, can be found. The phase diagram contains regions with either a unique bound shape or an additional meta-stable shape. Upon pulling, these shapes unbind discontinuously since the vesicles disengage from the substrate while still possessing a finite adhesion area.