Use of longitudinally displaced nanoscale electrodes for voltage sensing of biomolecules and other analytes in fluidic channels
Devices for detecting an analyte are provided. Devices for voltage sensing of analytes may comprise a plurality of fluidic channels defined in a substrate, each channel having a pair of sensing electrodes disposed in or adjacent to the fluidic channel and defining a detection volume for sensing voltage therein. At least one pair of electromotive electrodes for applying potential along at least one fluidic channel is provided as well.
1. A device for voltage sensing of analytes, the device comprising:
a plurality of fluidic channels, each defined by a trench in a substrate, each fluidic channel having at least one pair of sensing electrodes defining a detection zone disposed in each of the channels for sensing voltage therein, each detection zone comprising a first and a second sensing electrode disposed at two discrete laterally offset locations along a length of each fluidic channel, the sensing electrodes being connected to a voltmeter for measuring a voltage sensed by the sensing electrodes, and the pair of sensing electrodes not being connected to a voltage source; a first common channel disposed at the first ends of the plurality of fluidic channels; a second common channel disposed at the second ends of the plurality of fluidic channels; and at least one electromotive electrode disposed in each of the first and second common channels for applying a potential along the fluidic channels,
wherein the fluidic channels each comprise a nanochannel or a microchannel.
2. The device of claim 1 , wherein the electromotive electrodes apply a potential along the plurality of fluidic channels.
3. The device of claim 1 , wherein at least one fluidic channel is positioned above or below an electrically conductive element.
4. The device of claim 1 , wherein the substrate comprises a material selected from the group consisting of silicon, silicon dioxide, fused silica, and gallium arsenide.
5. The device of claim 1 , wherein each of the sensing and electromotive pairs of electrodes comprises a material selected from the group consisting of platinum, gold, chrome, titanium, silver chloride, silver, and graphene.
6. The device of claim 1 , wherein the first sensing electrode is disposed on a first side of the fluidic channel and the second sensing electrode is disposed on an opposing side of the fluidic channel.
7. The device of claim 1 , wherein each of the first and second sensing electrodes is disposed on a first side of the fluidic channel.
8. The device of claim 1 , wherein each of the first and second sensing electrodes transverses the fluidic channel.
9. The device of claim 1 , wherein at least one of the sensing electrodes is positioned adjacent to a proximal or distal end of the fluidic channel.
10. The device of claim 9 , wherein the first sensing electrode is positioned adjacent to the proximal end of the fluidic channel and the second sensing electrode is positioned adjacent to the distal end of the fluidic channel.
11. The device of claim 1 , wherein the first sensing electrode transverses the fluidic channel and the second sensing electrode is disposed on a side of the fluidic channel or adjacent to an end of the fluidic channel.
12. The device of claim 1 , wherein the electromotive pair of electrodes comprises macroscopic electrodes for generating a constant, changing, or oscillating electrophoretic force in the fluidic channel for translocation of an analyte disposed therein.
13. The device of claim 1 , further comprising a voltage amplifier disposed on the substrate.
14. The device of claim 1 , wherein at least one fluidic channel has a width selected from a range of 1 nm to 5 μm.
15. The device of claim 1 , wherein at least one fluidic channel has a depth selected from a range of 1 nm to 5 μm.
16. The device of claim 1 , wherein at least one fluidic channel has a length selected from a range of 1 μm to 10 cm.