Ion Channels on Silicon

Abstract

We present results showing that silicon substrates can be used as a universal platform for recording the electrical activity of ion channels inserted into suspended bilayer membranes. The bilayers span 150 μm apertures etched into silicon substrates using standard microelectronics processing techniques. The silicon is oxidized, patterned with a 75 μm thick SU-8 epoxy resist and then coated with a thin layer of polytetrafluoroethylene rendering the surface hydrophobic. Reversible Ag/AgCl electrodes are integrated around the circumference of the opening and provide long-term stable measurements of the ion channel currents. Characteristic measurements of OmpF porin ion channel protein in phospholipid bilayers and α-hemolysin toxin protein in triblock copolymer layers were made. Long-term measurements showed that ion channel activity could be recorded 22 hours after initial formation of a lipid bilayer. [DOI: 10.1380/ejssnt.2005.184]