Solid phase assay for use with a physical developer

• US 5,710,049 A
• Filed: 06/06/1995
• Issued: 01/20/1998
• Est. Priority Date: 06/05/1989
• Status: Expired due to Term

• Current Assignee: Janssen Pharmaceutica NV (Johnson & Johnson)
• Original Assignee: Janssen Pharmaceutica NV (Johnson & Johnson)
• Inventors: Garrevoet, Theo Cesar, Noppe, Marcus Joannes Maria
• Primary Examiner(s): Chin, Christopher L.
• Application Number:
  US08/468,944
• Time in Patent Office: 959 Days
• Field of Search: 422/55-58, 422/61, 422/101, 435/287.1, 435/287.2, 435/287.7, 435/287.8, 435/287.9, 435/805, 435/810, 435/970, 435/975, 436/514, 436/518, 436/525, 436/524, 436/169, 436/170, 436/805, 436/808, 436/810
• US Class Current: 436/525
• CPC Class Codes: G01N 33/54366 Apparatus specially adapted for solid-phase testing
• CPC Class Codes: G01N 33/585 with a particulate label, e.g. coloured latex
• CPC Class Codes: Y10S 435/805 Test papers
• CPC Class Codes: Y10S 435/81 Packaged device or kit
• CPC Class Codes: Y10S 435/962 Prevention or removal of interfering materials or reactants or other treatment to enhance results, e.g. determining or preventing nonspecific binding
• CPC Class Codes: Y10S 435/975 Kit
• CPC Class Codes: Y10S 436/805 Optical property
• CPC Class Codes: Y10S 436/808 Automated or kit
• CPC Class Codes: Y10S 436/81 Tube, bottle, or dipstick
• CPC Class Codes: Y10S 436/826 Additives, e.g. buffers, diluents, preservatives
• CPC Class Codes: Y10T 436/25375 Liberation or purification of sample or separation of material from a sample [e.g., filtering, centrifuging, etc.]
• CPC Class Codes: Y10T 436/255 including use of a solid sorbent, semipermeable membrane, or liquid extraction

Abstract

The present invention is directed to a new assay procedure and improved solid phase assay devices for use with a so-called physical developer. The invention provides a new assay procedure for detecting the presence of an analyte in a fluid sample using a tracer having a metal label which signal is enhanced by applying a physical developer. The assay is performed with a device having a support for a test area and having attached thereto a binder specific for the analyte to be detected. The assay comprises the steps of directing the fluid sample and the tracer through a porous medium into contact with the test area at a controlled flow rate to allow binding of the analyte with the binder and the tracer to the analyte, directing a physical developer through said porous medium to amplify the signal generated by the tracer, and separating the device to allow the test area to be read. The invention further relates to devices and immunoassay test kits for carrying out the improved immunoassay procedure. A first device FIG. 2 according to the present invention has a support 4 having upper and lower surfaces and a test area on its upper surface. A removable filter 3 overlies the upper surface of the support. A second device FIG. 1 according to the present invention has a support 4 having upper and lower surfaces and a test area on its lower surface which is in contact with the absorptive layer 2.

Claims

1. A device for use in detecting the presence of an analyte in a fluid sample using a tracer having a metal label and in which the signal of the tracer is enhanced by applying a physical developer, said device comprising:

a) a support having upper and lower surfaces and a test area on its lower surface;

b) a binder specific for the analyte covering the test area in a concentration whereby tracer specifically bound to bound analyte in the test area under assay conditions becomes visible; and

c) an absorptive layer in fluid communication with the lower surface of the support which receives liquids and any analyte and tracer not specifically bound at the test area;

wherein the support whereto the fluid sample, tracer and physical developer are applied has sufficiently small pore size to remove interfering substances present in the fluid sample and the physical developer, and large enough pore sizes to allow passage of liquid and any analyte and tracer, and wherein the support and the absorptive layer can be detached from each other to enable detection of bound tracer at the test area on the lower surface of the support.

2. An immunoassay kit comprising a device according to claim 1 in combination with a physical developer and a tracer having a colloidal gold label.