|approved||onepagesummaryosiv2.pdf||2015-03-27 12:26:37||Orly Tarun|
Author: Orly B Tarun
Requested Type: Oral
Submitted: 2015-03-27 11:09:43
Co-authors: Carlos Macias-Romero, Sylvie Roke
École Polytechnique Fédérale de Lausanne (EPFL)
The life and death of a cell is controlled by a 60 Å wide phospholipid membrane that separates the intra- and extracellular aqueous environments. The membrane-water system provides a platform for electro-chemical signaling processes. To understand these interactions, the membrane-water interface is ideally studied non-invasively on a molecular level.
In theory, label-free second harmonic generation can be used to probe the electrostatic potential at an interface, however the signal to noise ratio has so far been too poor for imaging the tiny changes in the water structure that follow potential changes. Having recently developed a second harmonic imaging system with a 3 orders of magnitude higher throughput, we demonstrate label-free imaging of water-membrane structure at freestanding planar lipid membranes (FPLM). Using FPLMs, we can mimic any type of membrane composition, control the liquid phases on both sides of the membrane and perform electrical characterization. We demonstrate the possibility of multisite voltage imaging in freestanding membranes.