Diagnostic detection device and method

• US 7,045,342 B2
• Filed: 03/05/2004
• Issued: 05/16/2006
• Est. Priority Date: 05/02/1995
• Status: Expired due to Fees

• Current Assignee: Church & Dwight Company Incorporated
• Original Assignee: Church & Dwight Company Incorporated
• Inventors: Nazareth, Albert, Boyle, Mary Beth, Cheng, Yea-Shun
• Primary Examiner(s): Chin, Christopher L.
• Application Number:
  US10/794,516
• Publication Number:
  US 20040171174A1
• Time in Patent Office: 802 Days
• Field of Search: 422/56, 422/57, 422/58, 422/61, 435/7.1, 435/7.2, 435/7.5, 435/7.93, 435/7.94, 435/287.2, 435/287.7, 435/287.9, 435/805, 435/810, 435/970, 435/7.95, 436/169, 436/518, 436/514, 436/524, 436/530, 436/535, 436/541, 436/810
• US Class Current: 435/287.1
• CPC Class Codes: G01N 33/54388 based on lateral flow
• CPC Class Codes: G01N 33/558 using diffusion or migration of antigen or antibody immunochromatographic test strips G01N33/54387
• CPC Class Codes: Y10S 435/805 Test papers
• CPC Class Codes: Y10S 435/81 Packaged device or kit
• CPC Class Codes: Y10S 435/97 Test strip or test slide
• CPC Class Codes: Y10S 436/81 Tube, bottle, or dipstick

Abstract

The invention provides an improved test cell for detecting the presence of an analyte in a liquid sample. The device has an elongate casing defining a liquid sample inlet, a reservoir volume, a test volume, and a window through the casing at the test volume. Disposed within the cell is a sample absorbent, a novel biphasic substrate and a reservoir, together capable of transporting an aqueous solution within the casing along a flow path extending from the sample inlet through the test volume and into the reservoir volume. The invention further comprises a method for detecting the presence of an analyte in a liquid sample using the device and a biphasic chromatographic material for carrying out the method.

Claims

1. A device for determining the presence in a liquid sample of an analyte wherein liquid sample deposited on a proximal end of the device travels downstream along a liquid path to a distal end of the device, the device comprising:

a biphasic substrate comprising (1) a release medium of a first material and, in fluid communication and downstream thereof, (2) a capture medium of a microporous, second, different material,

wherein located at the release medium of the biphasic substrate for release therefrom is

(i) a labeled conjugate comprising a binding member reactive with a first epitope of the analyte labeled with a detectable marker, and

(ii) a capturable component reactive with a second epitope of the analyte, such that if the analyte is present in the sample, the analyte produces a complex comprising the labeled conjugate, the analyte and the capturable component, and

located at the capture medium of the biphasic substrate is

a capture site for capturing the complex, the capture site having immobilized thereon a capture component having a binding affinity for the capturable component.

2. The device of claim 1 further comprising a control site located downstream of the capture site, the control site having immobilized thereon an agent having a binding affinity for the labeled conjugate.

3. The device of claim 1 wherein the capture medium is laminated to or cast on a transparent polymeric material.

4. The device of claim 1 comprising a sample absorbent located upstream of the biphasic substrate at the proximal end of the device.

5. The device of claim 1 further comprising a residual absorbent located downstream of the biphasic substrate at the distal end of the device.

6. The device of claim 1 wherein the binding member of the labeled conjugate is an antibody.

7. The device of claim 1 wherein the capturable component is a biotinylated antibody.

8. The device of claim 7 wherein the immobilized capture component comprises avidin, streptavidin or an antibiotin antibody.

9. The device of claim 1 wherein the immobilized capture component comprises avidin, streptavidin, or an antibiotin antibody.

10. The device of claim 1 wherein the second material of the biphasic substrate is nitrocellulose or nylon.

11. The device of claim 1 wherein the first material of the biphasic substrate is absorbent paper.

12. The device of claim 1 wherein the release medium and the capture medium of the biphasic substrate are both immobilized on a single backing support.

13. A device for determining the presence in a liquid sample of an analyte wherein liquid sample deposited on a proximal end of the device travels downstream along a liquid path to a distal end of the device, the device comprising:

a biphasic substrate comprising (1) a release medium of a first material and in fluid communication and downstream thereof, (2) a capture medium of a second, different material of nylon or nitrocellulose, wherein the release medium and the capture medium are both immobilized on a single backing support,

wherein located at the release medium of the biphasic substrate for release therefrom is

(i) a labeled conjugate comprising a first antibody that binds a first epitope of the analyte labeled with a detectable marker, and

(ii) a capturable component comprising a biotinylated second antibody that binds a second, different epitope of the analyte, such that if the analyte is present in the sample, the analyte produces a complex comprising the labeled conjugate, the analyte and the capturable component, and

located at the capture medium of the biphasic substrate is

a capture site for capturing the complex, the capture site having a capture component immobilized thereon for biding the capturable component.

14. The device of claim 13 further comprising a control site located downstream of the capture site, the control site having immobilized thereon an agent having binding affinity for the labeled conjugate.

15. The device of claim 13, wherein the capture medium is laminated to or cast on a transparent polymeric material.

16. The device of claim 13 further comprising a sample absorbent located upstream of the biphasic substrate at the proximal end of the device.

17. The device of claim 13 further comprising a residual absorbent located downstream of the biphasic substrate at the distal end of the device.

18. The device of claim 13, wherein the first material of the biphasic substrate is absorbent paper.

19. The device of claim 13, wherein the capture component is avidin or streptavidin.