Assay method for whole blood samples

• US 4,594,327 A
• Filed: 11/02/1983
• Issued: 06/10/1986
• Est. Priority Date: 11/02/1983
• Status: Expired due to Term

• Current Assignee: DADE Behring Beteiligungs GmbH (Siemens AG)
• Original Assignee: Syntec Incorporated (Atos SE)
• Inventors: Zuk, Robert F.
• Primary Examiner(s): Marantz, Sidney
• Assistant Examiner(s): WHITE, PATRICIA K
• Application Number:
  US06/548,165
• Time in Patent Office: 951 Days
• Field of Search: 436/514, 436/517, 436/528, 436/530, 436/810, 436/825, 436/827, 436/520, 436/541, 436/808, 435/7, 435/805, 422/56
• US Class Current: 436/514
• CPC Class Codes: G01N 33/54386 Analytical elements
• CPC Class Codes: G01N 33/80 involving blood groups or blood types or red blood cells white blood cells G01N33/56972
• CPC Class Codes: Y10S 435/805 Test papers
• 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 435/966 involving an enzyme system with high turnover rate or complement magnified assay, e.g. multi-enzyme systems
• CPC Class Codes: Y10S 435/97 Test strip or test slide
• CPC Class Codes: Y10S 435/975 Kit
• CPC Class Codes: Y10S 436/808 Automated or kit
• CPC Class Codes: Y10S 436/81 Tube, bottle, or dipstick
• CPC Class Codes: Y10S 436/825 Pretreatment for removal of interfering factors from sample
• CPC Class Codes: Y10S 436/827 Lectins

Abstract

Methods and compositions are provided for performing an assay on whole blood samples. The method is for a determination of an analyte which is a member of a specific binding pair (sbp) consisting of ligand and homologous receptor. The method involves a binding agent for the red blood cells in such sample, a solid bibulous element to which is bound at least one sbp member, and a signal-producing system. The method comprises combining the whole blood sample, the binding agent, and none or, where appropriate, one or more members of the signal producing system. The medium is next contacted with a portion of a solid bibulous element to which is bound one of the members of the specific binding pair to allow the medium to traverse such element (immunochromatography). The solid bibulous element is contacted with any remaining members of the signal producing system. Signal resulting from the signal producing system is detected and is related to the amount of the analyte in the sample.

Claims

1. A method for determining an analyte in a whole blood sample, said analyte being a member of a specific binding pair ("sbp member") selected from the group consisting of ligand and homologous receptor, which method comprises--

contacting in an aqueous medium (A) a bibulous element, at a predetermined region of said element, said element having an sbp member substantially uniformly bound to the surface thereof with (B) a whole blood sample and (C) a binding agent for red blood cells present in said whole blood sample

whereby said medium traverses said element to define a border related to the amount of analyte and said red blood cells aggregate at an area on said element adjacent to the air-liquid interface;

and

determining said border by means of a signal producing system, which system includes a labeled sbp member.

2. The method of claim 1 wherein the binding agent is an agglutinating agent.

3. The method of claim 1 wherein the binding agent is antibody specific for red blood cells.

4. The method of claim 1 wherein the binding agent is a lectin.

5. The method of claim 1 wherein the binding agent is a polymeric amino acid.

6. The method of claim 1 wherein the binding agent is polylysine.

7. The method of claim 1 wherein the pH of said medium is in the range of about 6-10.

8. The method of claim 1 wherein the ionic strength of said medium is in the range of about 0.1-0.4.

9. A method for detecting the presence of a member of a specific binding pair ("sbp member") in a whole blood sample, said sbp member selected from the group consisting of ligand and homologous receptor, where said method involves (1) a binding agent for red blood cells in said sample;

(2) a solid bibulous element to which is bound at least one sbp member; and

(3) a signal producing system capable of producing a detectable signal, the members of which include at least one label which is bound to an sbp member, said method comprising;

(a) combining in an aqueous medium a whole blood sample, a binding agent for aggregating red blood cells in said sample, and fewer than all the members of the signal producing system,

(b) contacting a portion of said bibulous carrier with said aqueous medium to allow said medium to diffuse along said bibulous element and said aggregated red blood cells to concentrate in an area on said element adjacent the air/liquid interface,

(c) contacting said bibulous element with any remaining members of the signal producing system, and

(d) detecting the signal as a result of said signal producing system, wherein said signal is related to the amount of said sbp member in said sample.

10. The method of claim 9 wherein the binding agent is antibody specific for said red blood cells.

11. A kit for use in a method for determining an analyte in a whole blood sample, said analyte being a member of a specific binding pair ("sbp member") selected from the group consisting of ligand and homologous receptor, which method comprises--

contacting in an aqueous medium (a) a bibulous element, at a predetermined region of said element, said element having an sbp member substantially uniformly bound to the surface thereof with (b) said whole blood sample and (c) a binding agent for red blood cells present in said whole blood sample;

whereby said medium traverses said element to define a border related to the amount of analyte and said red blood cells aggregate at a region on said element corresponding to the air-liquid interface; and

determining said border by means of a signal producing system, which system includes a labeled sbp member;

said kit comprising in a packaged combination in predetermined ratios for combination with said sample according to said method,

(a) a binding agent specific for said red blood cells,

(b) a bibulous element to which is bound at least one sbp member, and

(c) a signal producing system capable of producing a detectable signal in relation to the amount of analyte present in said sample.