Entropic Expulsion in Vesicles

Abstract

We report experimental observations and theoretical analysis of entropy driven expulsion in giant lipid vesicles, produced by the application of optical tweezers. The tweezers induce tension in membranes by attracting lipid material into the optical trap. This suppresses fluctuations in the vesicles and converts them into tense pressurized spheres. After shutting off the laser, overpressurized vesicles spontaneously expel inner vesicles, releasing their inner pressure.