Sensory Lipid Membrane Films with Integrated Ion Transporters

This study focuses on lipid bilayers resembling cell membranes, integrating ion transporters to capture specific solution-phase ions. Non-Faradaic capacitance spectroscopy is used to analyze ion-specific changes and hydration. The research involves lipid films composed of standard lipid (POPC), thiol-functionalized lipid (DPPTE), cholesterol, and transporters, formed on gold surfaces. Previous work successfully integrated cation and anion transporters into vesicle bilayers, enabling the flux of specific anions and their hydration shells. Electrochemical Impedance Spectroscopy (EIS) is employed to study ion and water flux in electrode-supported bilayer films. The study aims to determine bilayer structure, homogeneity, and surface properties. There is a particular focus on elucidating the confined water layer at the gold interface, considering lipid thiolation and ion transporter integration. Additionally, the proposed research examines how electrode potential affects interfacial water presence and ion flux. Experimental plans include analysing various bilayer samples with different salt concentrations and using neutron reflectometry. The findings will enhance our understanding of biological membranes with integrated ion transporters, with potential applications in biosensing and biophysics.