| AVS 54th International Symposium | |
| Understanding Biointerphases and Magnetism with Neutrons Topical Conference | Wednesday Sessions |
| Session NT+BI-WeM |
| Session: | Phospholipid Bilayers and Membranes |
| Presenter: | T. Charitat, CNRS-Université Louis Pasteur, France |
| Authors: | T. Charitat, CNRS-Université Louis Pasteur, France S. Lecuyer, Harvard University |
| Correspondent: | Click to Email |
Supported bilayer are interesting model systems for biologist and present also fascinating physical properties. We investigate experimentally these dynamical properties on floating bilayer. First, the equilibrium structures of single and double bilayers are studied by neutron reflectivity. The submicronic fluctuation spectrum of a floating bilayer is determined by off-specular X-ray scattering: surface tension, bending modulus and, for the first time with this technique, inter-membrane potential. Using fluorescence microscopy, we show that this single bilayer can be completely destabilized leading to well control vesicles formation. Destabilization can occur either at the main gel-fluid transition of the lipids, and can be interpreted in terms of a drop of bending rigidity, or under an AC low-frequency electric field applied in the fluid phase. In that last case we also study the effect of the electric field at the molecular length scale by neutron reflectivity. In both cases, the destabilization leads to the formation of relatively monodisperse vesicles, which could give a better understanding of the formation mechanism.