title: Electrochemical impedance spectroscopy for black lipid membranes fused with channel protein supported on solid-state nanopore.
abstract: Black lipid membranes (BLMs) have been used for detecting single-channel activities of pore-forming peptides and ion channels. However, the short lifetimes and poor mechanical stability of suspended bilayers limit their applications in high throughput electrophysiological experiments. In this work, we present a synthetic solid-state nanopore functionalized with BLM fused with channel protein. A nanopore with diameter of ~180 nm was electrochemically fabricated in a thin silicon membrane. Folding and painting techniques were demonstrated for production of stable suspended BLMs followed by incorporation of transmembrane protein, ENaC. Membrane formation was confirmed by employing electrochemical impedance spectroscopy (EIS) in the frequency regime of 10-2-105Hz. Results show that electrochemically fabricated solid state nanopore support resulted in excellent membrane stability, with >1 GΩ of up to 72 and 41 h for painting and folding techniques, respectively. After fusion of ENaC channel protein, the BLM exhibits the stability of ~5 h. We anticipate that such a solid-state nanopore with diameter in the range of 150-200 nm and thickness <1 µm could be a potential platform to enhance the throughput of ion-channel characterization using BLMs.
authors.affiliation: Electrical and Computer Engineering Department, University of Alabama in Huntsville, Huntsville, AL, 35899, USA. mskhan7@illinois.edu.
authors.forename: Muhammad S
authors.initials: MS
authors.lastname: Khan
authors.affiliation: Biotechnology Science and Engineering Program, University of Alabama in Huntsville, Huntsville, AL, 35899, USA.
authors.forename: Noura S
authors.initials: NS
authors.lastname: Dosoky
authors.affiliation: Department of Biomedical Sciences, Nazarbayev University School of Medicine, Astana, 010000, Kazakhstan.
authors.forename: Bakhrom K
authors.initials: BK
authors.lastname: Berdiev
authors.affiliation: Electrical and Computer Engineering Department, University of Alabama in Huntsville, Huntsville, AL, 35899, USA.
authors.forename: John D
authors.initials: JD
authors.lastname: Williams
mesh_terms: D015374:Biosensing Techniques; D002462:Cell Membrane / Q000737:chemistry*; D058266:Dielectric Spectroscopy; D053503:Epithelial Sodium Channels / Q000737:chemistry*; D058608:Nanopores
chemical_list: D053503:Epithelial Sodium Channels
keywords: Black lipid membranes; ENaC; Electrochemical impedance spectroscopy; Nanobiosensor; Silicon; Solid-state nanopore; Transmembrane protein