Observation of toroidal vesicles.

Abstract

In a recent article by Ou-Yang Zhong-can [Phys. Rev. A 41, 4517 (1990)], rings with generating circles of radii in the ratio 1 \ensuremath{\surd}2 have been found as stable equilibrium shapes of vesicle membranes, for some negative values of their spontaneous curvature. Here we report experimental observations of this topology in partially polymerized phospholipid membranes. Evaluating the radii of the generating circles of several toroidal vesicles we found agreement with the predicted value.