Electronic methods for the detection of analytes

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

Y is an aromatic group;

n is an integer from 1 to 50;

g is either 1 or zero;

e is an integer from zero to 10; and

m is zero or 1;

wherein when g is 1, B-D is a conjugated bond; and

wherein when g is zero, e is 1 and D is preferably carbonyl, or a heteroatom moiety, wherein the

heteroatom is selected from oxygen, sulfur, nitrogen, silicon or phosphorus; and

wherein

n is an integer from 1 to 50;

m is 0 or 1;

C is carbon;

J is carbonyl or a heteroatom moiety, wherein the heteroatom is selected from the group consisting of oxygen, nitrogen, silicon, phosphorus, sulfur; and

G is a bond selected from alkane, alkene or acetylene, wherein if m=0, at least one G is not alkane.

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 C l 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.