Electronic methods for the detection of analytes

• US 7,601,507 B2
• Filed: 10/30/2007
• Issued: 10/13/2009
• Est. Priority Date: 06/12/1997
• Status: Expired due to Fees

• Current Assignee: Osmetech Technology Inc. (Roche Holding AG)
• Original Assignee: Osmetech Technology Inc. (Roche Holding AG)
• Inventors: Kayyem, Jon Faiz, O'Connor, Stephen D., Meade, Thomas J.
• Primary Examiner(s): Cook; Lisa V
• Application Number:
  US11/981,645
• Publication Number:
  US 20090173640A1
• Time in Patent Office: 714 Days
• Field of Search: None
• US Class Current: 435/7.1
• 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: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G01N 2458/30 Electrochemically active labels
• CPC Class Codes: G01N 27/3277 being a redox reaction, e.g. detection by cyclic voltammetry voltammetry per se G01N27/42, G01N27/48
• CPC Class Codes: G01N 2800/04 Endocrine or metabolic disorders
• CPC Class Codes: G01N 33/5438 Electrodes
• CPC Class Codes: G01N 33/58 involving labelled substances G01N33/53 takes precedence
• CPC Class Codes: G01N 33/84 involving inorganic compounds or pH

Abstract

The present invention is directed to the detection of target analytes using electronic techniques, particularly AC techniques.

Claims

1. A method of detecting a protein target analyte in a sample comprising:

a) applying a first input signal to an assay complex comprising;

i) a redox active complex comprising;

1) a redox active molecule;

2) a binding ligand that will bind a protein target analyte; and

ii) said protein target analyte,

wherein said binding ligand is covalently attached to a first measuring electrode via a spacer, and wherein said first measuring electrode comprises;

a passivation agent monolayer comprising at least a covalently attached first passivation species and a covalently attached second passivation species comprising said binding ligand; and

b) detecting a change in the faradaic impedance of the system as a result of the association of the redox active molecule with said protein target analyte, if present.

2. The method according to claim 1, wherein said input signal comprises an AC component.

3. The method according to claim 1, wherein said input signal further comprises a DC component.

4. The method according to claim 1, wherein said redox active molecule is covalently attached to said electrode.

5. The method according to claim 1, wherein said binding ligand is covalently attached to said electrode.

6. The method according to claim 1, wherein said redox active molecule is a transition metal complex.

7. The method according to claim 6, wherein said transition metal complex is ferrocene.

8. The method according to claim 1, wherein said redox active molecule is covalently attached to said binding ligand.

9. The method according to claim 1, wherein said detecting is by receiving an output signal characteristic of the presence of said analyte.

10. The method according to claim 9, wherein said output signal comprises a current.

11. The method according to claim 1, wherein said conductive oligomer is selected from the group consisting of:

wherein

12. The method according to claim 1, wherein said binding ligand comprises a protein.

13. The method according to claim 12, wherein said protein is a peptide.

14. The method according to claim 1, wherein said binding ligand comprises a substrate of an enzyme.

15. The method according to claim 1, wherein said passivation agent monolayer comprises insulators.

16. The method according to claim 1, wherein said passivation agent monolayer comprises conductive oligomers.

17. The method according to claim 1, wherein said passivation agent monolayer comprises insulators and conductive oligomers.

18. The method according to claim 15, wherein said insulator comprises a Cl to C12 alkyl group.

19. The method according to claim 1, wherein binding ligand is covalently attached to said redox active molecule to form a redox active complex.

20. The method according to claim 19, wherein an atom of said binding ligand serves as a coordination atom to the transition metal to form a redox active complex.

21. The method according to claim 19, wherein said covalent attachment utilizes a branched linker.

22. The method according to claim 1, wherein said redox active molecule and said binding ligand are covalently attached to said first measuring electrode separately.