Electrochemical Assay

• US 20090035876A1
• Filed: 03/31/2006
• Published: 02/05/2009
• Est. Priority Date: 03/31/2005
• Status: Abandoned Application

• Current Assignee: Inverness Medical Switzerland GmbH (Abbott Laboratories)
• Original Assignee: Inverness Medical Switzerland GmbH (Abbott Laboratories)
• Inventors: Thomson, Alan, Williams, David Edward, Carlisle, Stephen John, Herve, Anne-Cecile, Lowe, Phillip, Slevin, Christopher John
• Application Number:
  US11/887,393
• Publication Number:
  US 20090035876A1
• Time in Patent Office: Days
• US Class Current: 436/529
• CPC Class Codes: G01N 33/532 Production of labelled immunochemicals
• CPC Class Codes: G01N 33/5438 Electrodes
• CPC Class Codes: G01N 33/58 involving labelled substances G01N33/53 takes precedence

Abstract

A method of determining the presence or amount of analyte in a fluid sample, which comprises: contacting a fluid sample with a binding reagent that comprises a plurality of cleavable species and wherein said species, when cleaved, are detectable using electrochemical means; separating any binding reagent-analyte complex that forms from the unbound binding reagent; cleaving the cleavable species from the immobilized binding reagent-analyte complex; and detecting the cleaved species using electrochemical means.

Claims

1. A method of determining the presence or amount of analyte in a fluid sample, which comprises:

(a) contacting a fluid sample with a binding reagent that comprises a plurality of cleavable species and wherein said species, when cleaved, are detectable using electrochemical means;

(b) separating any binding reagent-analyte complex that forms from the unbound binding reagent;

(c) cleaving the cleavable species from the immobilized binding reagent-analyte complex; and

(d) detecting the cleaved species using electrochemical means.

2. A method according to claim 1, wherein the binding reagent-analyte complex is separated from the unbound binding reagent by immobilization of the binding reagent-analyte complex in a capture phase.

3. A method according to claim 1, wherein the binding reagent comprises at least 10⁶ cleavable species.

4. A method according to claim 1, wherein the cleavable species are photocleavable or acid cleavable.

5. A method according to claim 1, wherein the cleavable species show electrochemical activity when they have been cleaved from the binding reagent.

6. A method according to claim 1, wherein the cleavable species are transformable, after being cleaved from the binding reagent, into an electrochemically active species.

7. A method according to claim 1, wherein the cleavable species, after being cleaved from the binding reagent, result in further species becoming electrochemically active.

8. A method according to claim 1, wherein the cleavable species is not electrochemically active when attached to the binding reagent.

9. A method according to claim 1, wherein the cleavable species comprises a moiety derived from ferrocene, nitrophenol, aminophenol, hydroquinone, salicylic acid or sulfosalicylic acid.

10. A method according to claim 1, wherein the cleavable species comprises a moiety derived from ferrocene aldehyde.

11. A method according to claim 1, wherein the cleavable species comprises one or more moieties derived from ethylene glycol.

12. A method according to claim 1, wherein the binding reagent comprises a central core.

13. A method according to claim 12, wherein the central core is a polymer sphere.

14. A method according to claim 1, wherein the binding reagent comprises at least one dendritic or polymeric moiety.

15. A method according to claim 14 wherein the cleavable species are attached to the dendritic or polymeric moiety.

16. A method according to claim 15, wherein the dendritic or polymeric moiety is attached to the central core.

17. A method according to claim 14, wherein the dendritic or polymeric moiety is provided on the outer surface of the cleavable species.

18. A method according to claim 14, wherein the polymeric moiety is derived from dextran.

19. A method according to claim 1, wherein the electrochemical means comprises an electrode.

20. A binding reagent suitable for use in an immunoassay which comprises a plurality of cleavable species and wherein said species, when cleaved, are detectable using electrochemical means.

21. A method of performing an immunoassay which uses a binding regent which comprises a plurality of cleavable species and wherein said species, when cleaved, are detectable using electrochemical means.

22. An assay kit for measuring the amount or presence of an analyte in a sample, comprising:

a binding reagent which comprises a plurality of cleavable species and wherein said species, when cleaved, are detectable using electrochemical means;

a capture phase comprising a support having a reagent which is capable of binding or attaching to a binding-reagent-analyte complex; and

an electrode capable of detecting the cleavable species, when cleaved, to provide an indication of the presence or amount of analyte present.