Skip to main content
. Author manuscript; available in PMC: 2014 Apr 16.
Published in final edited form as: Anal Chem. 2013 Feb 18;85(8):3871–3878. doi: 10.1021/ac302972c

Figure 4.

Figure 4

Measured noise characteristics of microfluidics-integrated and non-integrated membranes and nanopores. (a) Power-spectral density at no applied bias, sampled at 250 kHz and filtered at 100 kHz for ionic current measurements across: a (350 μm)2 exposed SiNx membrane area (red), a (70 μm)2 exposed SiNx membrane area, (orange), and a (6 μm)2 exposed membrane area between two perpendicular microchannels (green). (b) RMS noise over 10 s of data filtered at 100 kHz versus exposed membrane area. Horizontal line represents Axopatch 200B noise floor, obtained by measuring RMS noise in a 200 MΩ high-quality resistor at 0 V. (c) Comparison between predicted and experimental RMS noise as a function of bandwidth for the (70 μm)2 exposed membrane area (orange), and (6 μm)2 area in the microfluidics-integrated device (green). (d) Power-spectral density at no applied bias, sampled at 250 kHz and filtered at 100 kHz in 1 M KCl (dark red) and 10 mM KCl (dark green) with TBE in a 20 nm SiO2 coated nanopore in the microfluidics-integrated device, compared with 10 MΩ (light red) and 100 MΩ (light green) resistors. Nanopore resistances are also indicated.