Bilayer reconstitution of voltage-dependent ion channels using a microfabricated silicon chip.
Painted bilayers containing reconstituted ion channels serve as a well defined model system for electrophysiological investigations of channel structure and function. Horizontally oriented bilayers with easy solution access to both sides were obtained by painting a phospholipid:decane mixture across a cylindrical pore etched into a 200-microm thick silicon wafer. Silanization of the SiO(2) layer produced a hydrophobic surface that promoted the adhesion of the lipid mixture. Standard lithographic techniques and anisotropic deep-reactive ion etching were used to create pores with diameters from 50 to 200 microm. The cylindrical structure of the pore in the partition and the surface treatment resulted in stable bilayers. These were used to reconstitute Maxi K channels in the 100- and 200-microm diameter pores. The electrophysiological characteristics of bilayers suspended in microchips were comparable with that of other bilayer preparations. The horizontal orientation and good voltage clamping properties make the microchip bilayer method an excellent system to study the electrical properties of reconstituted membrane proteins simultaneously with optical probes.
Pantoja
R
R
Department of Chemistry and Biochemistry, School of Medicine, University of California, Los Angeles, California 90095, USA.
Sigg
D
D
Blunck
R
R
Bezanilla
F
F
Heath
J R
JR
D000473:Alkanes / Q000737:chemistry*; D004594:Electrophysiology; D007473:Ion Channels / Q000737:chemistry / Q000378:metabolism*; D051036:Large-Conductance Calcium-Activated Potassium Channels; D008051:Lipid Bilayers / Q000737:chemistry* / Q000378:metabolism; D008564:Membrane Potentials / Q000502:physiology; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism; D008954:Models, Biological; D010743:Phospholipids / Q000737:chemistry*; D015221:Potassium Channels / Q000737:chemistry / Q000378:metabolism*; D024681:Potassium Channels, Calcium-Activated; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties
D000473:Alkanes; D007473:Ion Channels; D051036:Large-Conductance Calcium-Activated Potassium Channels; D008051:Lipid Bilayers; D008565:Membrane Proteins; D010743:Phospholipids; D015221:Potassium Channels; D024681:Potassium Channels, Calcium-Activated; D012822:Silicon Dioxide; C012867:decane