Imaging of voltage-gated alamethicin pores in a reconstituted bilayer lipid membrane via scanning electrochemical microscopy

Analyst. 2006 Feb;131(2):311-6. doi: 10.1039/b510649d. Epub 2005 Nov 30.

Abstract

Voltage-gated biological ion channels were simulated by insertion of the peptaibol antibiotic alamethicin into reconstituted phosphatidylcholine bilayer lipid membranes (BLMs). Scanning electrochemical microscopy (SECM) was utilized to probe initial BLM resistivity, the insertion of alamethicin pores, and mass transport across the membrane. Acquired SECM images show the spatial location of inserted pore bundles, the verification of voltage control over the pore conformational state (open/closed), and variations in passive mass transport corresponding to different topographical areas of the BLM. SECM images were also used to evaluate overall BLM integrity prior to insertion as well as transport (flux in open state) and leakage (flux in closed state) currents following insertion.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Alamethicin / analysis*
  • Anti-Bacterial Agents / analysis*
  • Electrochemistry / methods*
  • Ion Channel Gating
  • Ion Channels / analysis*
  • Iontophoresis
  • Lipid Bilayers
  • Microscopy, Electron, Scanning*

Substances

  • Anti-Bacterial Agents
  • Ion Channels
  • Lipid Bilayers
  • Alamethicin