Multi‐Scale Lipid Membrane Flow by Electron Beam‐Induced Electrowetting

Abstract

AbstractThis study proposes a new technique for control of lipid membrane flow using an electron beam (EB)‐induced virtual cathode (VC). A spot 2.5 keV EB is indirectly irradiated onto supported lipid bilayers (SLBs) which are formed on a 100‐nm‐thick silicon nitride (SiN) membrane, and then a focused electric field around the EB spot (that is, the VC) causes membrane flow of the SLBs due to a voltage drop across them and electrowetting effects between them and the SiN membrane. This VC technique is shown to be able to change membrane shapes by small‐ and large‐scale controls of lipid membrane flow. For SLBs consisting of a single component, a spot VC can achieve small‐scale control of membrane flow; and the edge of the SLBs is demonstrated to change only around the spot VC. It is also shown that the spot VC can cause large‐scale deformation of SLBs consisting of ternary components by inducing a surface instability phenomenon known as Saffman–Taylor instability. The obtained results indicate that the proposed VC technique can achieve multi‐scale control of lipid membrane flow, which will contribute to on‐demand control of network topology in biomolecular devices based on artificial lipid membranes.