Methods and compositions for enhancing immunoassays

• US 9,983,206 B2
• Filed: 03/13/2014
• Issued: 05/29/2018
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Board of Trustees of The University of Illinois
• Original Assignee: Board of Trustees of The University of Illinois
• Inventors: Bailey, Ryan C., Luchansky, Matthew S., Qavi, Abraham J., Kindt, Jared T.
• Primary Examiner(s): Grossman, Andrea S
• Application Number:
  US14/209,746
• Publication Number:
  US 20140273029A1
• Time in Patent Office: 1,538 Days
• CPC Class Codes: G01N 2333/5412 IL-6
• CPC Class Codes: G01N 2333/55 IL-2
• CPC Class Codes: G01N 33/54373 involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings

Abstract

Embodiments of the methods, compositions, and systems provided herein relate to enzymatic enhancement of immunoassays using photonic sensor arrays.

Claims

1. A method of detecting interleukin-2 (IL-2) comprising:

(a) obtaining a fluidic cell comprising an optical ring resonator having a first anti-cytokine antibody attached thereto, wherein the first anti-cytokine antibody is anti-IL-2 from clone 555051 antibody;

(b) contacting the first anti-cytokine antibody with a sample comprising IL-2 that selectively binds to the anti-cytokine antibody;

(c) contacting the bound IL-2 with a second anti-cytokine antibody that selectively binds to the IL-2, wherein the second anti-cytokine antibody is a biotinylated anti-IL-2 from clone 555040 antibody;

(d) contacting the biotinylated second anti-cytokine antibody with a streptavidin-horseradish peroxidase conjugate;

(e) contacting the horseradish peroxidase with a substantially continuous flow of a solution comprising 4-chloro-1-naphthol and hydrogen peroxide, under conditions that oxidize 4-chloro-1-naphthol to 4-chloro-1-naphthon, whereby the 4-chloro-1-naphthon precipitates on the surface of the optical ring resonator during the substantially continuous flow of the solution; and

(f) measuring a change in resonance wavelengths of the optical ring resonator, thereby indicating the presence of the IL-2.

2. The method of claim 1, wherein the concentration of hydrogen peroxide is less than about 0.003%.

3. The method of claim 1, wherein a concentration of the cytokine less than about 100 pg/ml is detected.

4. The method of claim 1, wherein a continuous flow of reagents contacting the optical ring resonator having a first anti-cytokine antibody attached thereto is maintained for step (b).

5. The method of claim 1, wherein a substantially continuous flow of reagents contacting the optical ring resonator having a first anti-cytokine antibody attached thereto is maintained for each of steps (b), (c), (d), and (e).

6. The method of claim 1, wherein a continuous flow of reagents contacting the optical ring resonator having a first anti-cytokine antibody attached thereto is maintained for each of steps (b), (c), (d), and (e).

7. The method of claim 1, wherein steps (b)-(e) comprise maintaining a flow of reagents contacting the optical ring resonator having a first anti-cytokine antibody attached thereto.

8. The method of claim 7, wherein the flow rate of the reagents is about 30 μ

L/min.

9. The method of claim 1, wherein a continuous flow of the solution is maintained for step (e).

10. The method of claim 9, wherein the continuous flow of the solution is maintained for steps (e) and (f).