Detection of single channel activities on a high throughput device is of major interest for pharmaceutical industries developing new drugs targeting ion channels. A silicon chip, with 9 silicon membranes having a micron aperture each, was functionalized and characterized with ion channels. To minimize the current noise due to the interaction of the preamplifier with the total capacitance, we add thick SiO2 layers (7 µm TEOS and 1 µm PECVD) to decrease the capacitance of the chip. The surface of the chips was treated by oxygen plasma and functionalized with lipid bilayers using the giant unilamellar vesicle fusion technique. The channel-forming peptide Gramicidin and the larger protein -alamethicin were inserted in the bilayer.We have shown here the possibility to use silicon chips in detecting single channel currents in the pA range, by the use of a thick passivating silicon oxide layer on the chip, resulting in single channel activity measurements with a RMS current noise of 0.56 pA at 1 kHz Bessel acquisition filter and 10 kHz sampling frequency.
Journal: TechConnect Briefs
Volume: 2, Nanotechnology 2008: Life Sciences, Medicine & Bio Materials – Technical Proceedings of the 2008 NSTI Nanotechnology Conference and Trade Show, Volume 2
Published: June 1, 2008
Pages: 562 - 565
Industry sectors: Medical & Biotech | Sensors, MEMS, Electronics
Topic: Chemical, Physical & Bio-Sensors