Eur. Phys. J. B 12, 413-419 (1999)
https://doi.org/10.1007/s100510051023

Attractive forces between anisotropic inclusions in the membrane of a vesicle

¹ Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
² Fachbereich Physik -Theoretische Physik, Bergische Universität Wuppertal, Gaußstraße 20, 42097 Wuppertal, Germany

Corresponding author: ^a holzloehner@umbc.edu

Received: 5 February 1999
Revised: 14 May 1999
Published online: 15 December 1999

Abstract

The fluctuation-induced interaction between two rod-like, rigid inclusions in a fluid vesicle is studied by means of canonical ensemble Monte-Carlo simulations. The vesicle membrane is represented by a triangulated network of hard spheres. Five rigidly connected hard spheres form rod-like inclusions that can leap between sites of the triangular network. Their effective interaction potential is computed as a function of mutual distance and angle of the inclusions. On account of the hard-core potential among these, the nature of the potential is purely entropic. Special precaution is taken to reduce lattice artifacts and the influence of finite-size effects due to the spherical geometry. Our results show that the effective potential is attractive and short-range compared with the rod length L. Its well depth is of the order of , where κ is the bending modulus.