The frequency dependence of phospholipid vesicle shapes in an external electric field.

Experiments show that phospholipid vesicles exposed to AC electric field undergo a shape transition from prolate to oblate ellipsoidal shape when the frequency of the field is increased. A theoretical model, based on the minimization of total free energy of the vesicle, was devised to explain this phenomenon. The model exhibits the same frequency-dependent prolate-to-oblate shape transition as observed in the experiment.