Electrooptic behavior and structure of novel polymer-vesicle hybrids

It has been previously shown that polymerization of styrene in DODAB vesicl es gives rise to the formation of unique parachute-like structures in which a polymer bead is confined to the bilayer at one pole of the vesicle. In t his paper, quantitative data on the size and the shape of these hybrid part icles and of the bare DODAB vesicles are obtained by combination of cryo-TE M, transient electrooptic birefringence (Kerr effect), and dynamic light sc attering. Also, this study qualitatively assesses the influence of the conf ined polymer bead on the electrooptic behavior. It turns out that the prese nce of the bead gives rise to a special response in the transient electroop tic birefringence, typical of the existence of permanent dipoles. Unlike ot her vesicles, the DODAB vesicles and the polymer/vesicle hybrids do not dis play a deformation step in their electrooptic response. As such, these part icles act as rigid particles under the action of an electric field. The the rmal behavior of the DODAB templates and parachutes is investigated and exp lained in terms of intrinsic vesicle properties.