Shape transitions of giant liposomes induced by an anisotropic spontaneous curvature

Abstract

An original shape transition of giant magnetic liposomes triggered by the ionic strength is studied. The transition between prolate and oblate ellipsoids were observed under an applied ac electric field. It was predicted for an applied magnetic field that the sign of magnetic anisotropy of the lipid molecules themselves leads either to prolate or oblate deformations. However, the magnetically induced ellipticity was far too small to be detected experimentally, even in a strong field H0 = 104 Oe. The advantage of the magnetic properties of the encapsulated solution was used to improve the coupling between the magnetic field and the bending energy of the vesicles.