Nanowire-based sensor configurations

• US 7,910,064 B2
• Filed: 04/06/2006
• Issued: 03/22/2011
• Est. Priority Date: 06/03/2003
• Status: Active Grant

• Current Assignee: GLO Technologies LLC
• Original Assignee: Nanosys Incorporated (Shoei Electronic Materials, Inc.)
• Inventors: Chow, Calvin Y. H., Dubrow, Robert S., Hamilton, James M.
• Primary Examiner(s): BROWN, MELANIE YU
• Application Number:
  US11/399,218
• Publication Number:
  US 20090124025A1
• Time in Patent Office: 1,811 Days
• Field of Search: 435/4, 435/7.1, 435/283.1, 435/287.1, 435/288.7, 435/287.2, 435/288.3, 422/50, 422/61, 422/82.01, 422/82.02, 436/518, 436/524, 436/525
• US Class Current: 422/82.01
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: G01N 27/127 comprising nanoparticles
• CPC Class Codes: G01N 27/4146 involving nanosized elements, e.g. nanotubes, nanowires
• CPC Class Codes: G01N 33/54313 the carrier being characterised by its particulate form

Abstract

This invention provides nanowire based molecular sensors and methods for detecting analytes in a microfluidic system. Methods for sensing analytes include detecting changed electrical parameters associated with contact of a nanowire with the analyte in a microfluidic system. Sensors of the invention include nanowires mounted in microchambers of a microfluidic system in electrical contact with the detector, whereby electrical parameter changes induced in the nanowire by the analyte can be monitored by the detector.

Claims

1. A method of detecting an analyte of interest, comprising:

providing a nanowire having a sample exposure region, the sample exposure region comprising at least one binding molecule for an analyte of interest disposed thereon, the nanowire being operably coupled to an electrical parameter detector;

contacting the sample exposure region with a sample material suspected of containing the analyte of interest for a first period of time to allow any analyte of interest in the sample material to associate with the sample exposure region of the nanowire;

treating the nanowire to rapidly remove at least a portion of the analyte of interest from association with the sample exposure region; and

monitoring the electrical parameter of the nanowire during at least the treating step and the removal of at least a portion of the analyte to detect a change in the electrical parameter of the nanowire in response to the treating step, the change in the electrical parameter being indicative of a presence or amount of the analyte of interest bound to the sample exposure region from the sample material.

2. The method of claim 1, wherein said treating the nanowire comprises exposing the nanowire to ultraviolet light to remove at least a portion of the analyte of interest from association with the sample exposure region.

3. The method of claim 1, wherein said treating the nanowire comprises exposing the nanowire to heat to remove at least a portion of the analyte of interest from association with the sample exposure region.

4. The method of claim 1, wherein said treating the nanowire comprises exposing the nanowire to an enzyme to remove at least a portion of the analyte of interest from association with the sample exposure region.

5. The method of claim 1, wherein said treating the nanowire comprises exposing the nanowire to a wash solution to remove at least a portion of the analyte of interest from association with the sample exposure region.

6. The method of claim 1, wherein said treating the nanowire comprises exposing the nanowire to an electrical current to remove at least a portion of the analyte of interest from association with the sample exposure region.

7. The method of claim 1, further comprising exposing the nanowire to a low ionic strength solution prior to monitoring the electrical parameter.

8. The method of claim 1, wherein the at least one binding molecule includes nucleic acids, peptite nucleic acids, antibodies, receptors, lectins, charged groups and/or chelators.

9. The method of claim 1, wherein the nanowire is piezoresistive, and wherein the change in the electrical parameter comprises a change in resistance of the piezoresistive nanowire.

10. The method of claim 1, wherein the nanowire exhibits an electrical field effect to provide a change in the electrical parameter.

11. The method of claim 10, wherein the nanowire is configured as a gate region in a transistor.

12. The method of claim 1, further comprising comparing the electrical parameter or the change thereof to that monitored for a control nanowire lacking the at least one binding molecule, and analyzing the comparison to determine background noise or other nonspecific interference.

13. The method of claim 1, wherein the electrical parameter is resistance.

14. The method of claim 1, wherein the electrical parameter is voltage.

15. The method of claim 1, wherein the electrical parameter is current.

16. A method of detecting an analyte of interest, comprising:

providing a nanowire having a sample exposure region, the sample exposure region comprising at least one binding molecule for an analyte of interest disposed thereon, the nanowire being operably coupled to an electrical parameter detector;

contacting the sample exposure region with a sample material suspected of containing the analyte of interest for a first period of time to allow any analyte of interest in the sample material to associate with the sample exposure region of the nanowire;

treating the nanowire to rapidly remove at least a portion of the analyte of interest from association with the sample exposure region; and

monitoring the electrical parameter of the nanowire during at least the treating step to detect a change in the electrical parameter of the nanowire in response to the treating step, the change in the electrical parameter being indicative of a presence or amount of the analyte of interest bound to the sample exposure region from the sample material.

17. The method of claim 16, wherein the electrical parameter is electrical resistance.

18. The method of claim 16, wherein the electrical parameter is resistance.

19. The method of claim 16, wherein the electrical parameter is voltage.

20. The method of claim 16, wherein the electrical parameter is current.

21. The method of claim 16, wherein the nanowire is configured as a gate region in a transistor.

22. The method of claim 16, wherein the treating step is done after a plurality of the analytes are bound to the nanowire.