Nonaxisymmetric phospholipid vesicles: Rackets, boomerangs, and starfishP. Ziherl1, 2 and S. Svetina2, 3
1 Department of Physics, University of Ljubljana - Ljubljana, Slovenia
2 J. Stefan Institute - Ljubljana, Slovenia
3 Institute of Biophysics, Faculty of Medicine, University of Ljubljana Ljubljana, Slovenia
received 4 August 2004; accepted in final form 15 April 2005
published online 4 May 2005
Within the area difference elasticity model, we numerically minimize the bending energy of phospholipid vesicles to study the nonaxisymmetric shapes at the oblate-prolate transition. We analyze the onset of a coherent structural hierarchy of hybrid shapes such as rackets, boomerangs, and starfish, which all consist of a flattened body and one or more elongated arms. The phase diagram of these shapes is characterized by a critical point terminating the line of discontinuous transitions between rackets and boomerangs/starfish. The critical point is located very close to the discocyte with the volume of a human erythrocyte, implying that in this part of the parameter space minute variations of volume and area difference can induce large changes of shape.
87.16.-b - Subcellular structure and processes.
87.16.Ac - Theory and modeling; computer simulation.
87.16.Dg - Membranes, bilayers, and vesicles.
© EDP Sciences 2005