title: Lipid bilayer coated Al(2)O(3) nanopore sensors: towards a hybrid biological solid-state nanopore.
abstract: Solid-state nanopore sensors are highly versatile platforms for the rapid, label-free electrical detection and analysis of single molecules, applicable to next generation DNA sequencing. The versatility of this technology allows for both large scale device integration and interfacing with biological systems. Here we report on the development of a hybrid biological solid-state nanopore platform that incorporates a highly mobile lipid bilayer on a single solid-state Al(2)O(3) nanopore sensor, for the potential reconstitution of ion channels and biological nanopores. Such a system seeks to combine the superior electrical, thermal, and mechanical stability of Al(2)O(3) solid-state nanopores with the chemical specificity of biological nanopores. Bilayers on Al(2)O(3) exhibit higher diffusivity than those formed on TiO(2) and SiO(2) substrates, attributed to the presence of a thick hydration layer on Al(2)O(3), a key requirement to preserving the biological functionality of reconstituted membrane proteins. Molecular dynamics simulations demonstrate that the electrostatic repulsion between the dipole of the DOPC headgroup and the positively charged Al(2)O(3) surface may be responsible for the enhanced thickness of this hydration layer. Lipid bilayer coated Al(2)O(3) nanopore sensors exhibit excellent electrical properties and enhanced mechanical stability (GΩ seals for over 50 h), making this technology ideal for use in ion channel electrophysiology, the screening of ion channel active drugs and future integration with biological nanopores such as α-hemolysin and MspA for rapid single molecule DNA sequencing. This technology can find broad application in bio-nanotechnology.
authors.affiliation: Department of Electrical and Computer Engineering, University of Illinois at Urbana Champaign, Illinois, IL 61801, USA.
authors.forename: Bala Murali
authors.initials: BM
authors.lastname: Venkatesan
authors.forename: James
authors.initials: J
authors.lastname: Polans
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Comer
authors.forename: Supriya
authors.initials: S
authors.lastname: Sridhar
authors.forename: David
authors.initials: D
authors.lastname: Wendell
authors.forename: Aleksei
authors.initials: A
authors.lastname: Aksimentiev
authors.forename: Rashid
authors.initials: R
authors.lastname: Bashir
mesh_terms: D000537:Aluminum Oxide / Q000138:chemical synthesis / Q000737:chemistry*; D015374:Biosensing Techniques; D004247:DNA / Q000737:chemistry; D036681:Fluorescence Recovery After Photobleaching / Q000379:methods; D007473:Ion Channels / Q000737:chemistry; D008051:Lipid Bilayers / Q000138:chemical synthesis / Q000737:chemistry*; D008954:Models, Biological; D056004:Molecular Dynamics Simulation; D058608:Nanopores; D036103:Nanotechnology; D010713:Phosphatidylcholines / Q000737:chemistry; D017422:Sequence Analysis, DNA; D012822:Silicon Dioxide / Q000737:chemistry; D013194:Staining and Labeling; D014025:Titanium / Q000737:chemistry
chemical_list: D007473:Ion Channels; D008051:Lipid Bilayers; D010713:Phosphatidylcholines; C009495:titanium dioxide; D012822:Silicon Dioxide; D004247:DNA; D014025:Titanium; C017251:1,2-oleoylphosphatidylcholine; D000537:Aluminum Oxide