Studying membranes with scanning force microscopy and patch-clamp technique

Abstract

The application of scanning probe techniques to biological molecular structures is a rapidly developing field. Here, we describe the combination of a scanning force microscope with the electrophysiological patch-clamp technique. The latter technique allows electrical control of a membrane preparation and direct measurement of the function of transmembrane proteins like ion channels. In addition, the solution composition of either side of the membrane can be controlled and membrane tension can be varied by applying pressure or suction to the patch pipette. We show results of our investigation of the mechanical and electro-mechanical properties of excised membrane vesicles and inside-out patches from Xenopus oocytes. Our observations favor the theory that parts of the cytoskeleton are excised together with the plasma membrane. They seem to stabilize the lipid bilayer leading to a relatively high elasticity of the membrane patch. © 1996 American Vacuum Society.