Determination of immunologically active materials and system therefore

• US 4,198,389 A
• Filed: 08/17/1977
• Issued: 04/15/1980
• Est. Priority Date: 08/20/1976
• Status: Expired due to Term

• Current Assignee: Roche Diagnostic Systems Incorporated (Roche Holding AG)
• Original Assignee: Hoffmann-La Roche Incorporated (Roche Holding AG)
• Inventors: Wadsworth, Charles
• Primary Examiner(s): Fagelson, Anna P.
• Application Number:
  US05/825,500
• Time in Patent Office: 972 Days
• Field of Search: 424/3, 424/8, 424/11, 424/12, 424/13, 23/230 R, 23/230 B, 204/299 R, 204/180 G, 422/56
• US Class Current: 436/513
• CPC Class Codes: G01N 33/559 through a gel, e.g. Ouchterlony technique
• CPC Class Codes: Y10S 436/806 Electrical property or magnetic property
• CPC Class Codes: Y10S 436/807 Apparatus included in process claim, e.g. physical support structures

Abstract

A method and system for a rapid and sensitive method for determining immunologically active materials in a biological fluid by observing an antigen-antibody reaction after application of reactants on the surface of a gel matrix and applying an alternating current thereto.

Claims

1. Process for determining an immunologically-active material in a fluid, comprising using an inert gel matrix on a non-reactive support, said inert gel matrix containing an electrolyte and two opposite sides of said gel matrix being connected to an alternating current source means, applying an aliquot of a sample of the fluid onto said gel, covering the area of application with a solution containing an immunologically-specific counter-reactive material, applying an alternating current to said gel matrix, removing the unreacted soluble materials and observing the results of the immunological reaction at the area of application of the sample.

2. Process according to claim 1 wherein the immunologically active material is an antigen or an antibody and the counter-reactive material is an antibody specific for this antigen or antibody.

3. Process according to claim 1 wherein the immunologically active material is an antibody and the counter-reactive material a corresponding antigen.

4. Process according to claim 1 wherein the non-reactive support is a plate.

5. Process according to claim 1 wherein the results of the immunological reaction are observed after staining.

6. Process according to claim 1 wherein the non-reactive support is transparent.

7. Process according to claim 1 wherein the gel contains an additive decreasing the surface tension.

8. Process according to claim 1 wherein the immunologically active material is IgA.

9. Process according to claim 1 wherein the immunologically active material is IgG.

10. Process according to claim 1 wherein the immunologically active material is IgM.

11. Process according to claim 1 wherein the immunologically active material is C-Reactive Protein.

12. Process for determining the total protein content in a fluid by the method of claim 1, wherein the immunologically-active material is protein.

13. Process according to claim 1 wherein

(a) a gel matrix is formed on a plate of a nonreactive material

(b) a small volume of a biological fluid to be analyzed is applied onto the gel surface and it is allowed to be taken up by the gel,

(c) the area of application is covered with a solution containing a suitable concentration of an immunologically-specific counter-reactive material for the component to be determined in an amount greater than that of the first applied fluid so that during a sufficient period of time there is an excess of material enabling the components to react with each other to form an insoluble immunoprecipitate during the application of the alternating current,

(d) the gel matrix is washed at least once with a buffer solution and thereafter an absorption paper is pressed against the matrix so that the components which have not taken part in the reaction and remain still soluble are removed,

(e) the gel is rinsed and then pressed with an absorption paper again to a thin layer and the gel is dried with the last absorption paper in place,

(f) the paper is removed and the plate submerged in a solution of stain absorbable by the immunoprecipitate and the gel is destained so that the background of the stained areas becomes clear, and

(g) the stained areas are compared with a known color scale indicating the color intensity as a function of the amount of precipitate.

14. Process according to claim 13 wherein a fluid containing a number of different components to be determined is applied on the gel matrix, in a predetermined pattern in several areas;

certain parts of that pattern are covered with solutions containing the desired specific counter-reactants, and the gel matrix is then treated according to steps d-g in claim 6.

15. The process of claim 13 further comprising the preparation of the color scale of step (g), wherein at least three different gradations of color are produced on the gel matrix by employing for said fluid to be analyzed at least three solutions, each containing a different predetermined amount of said component to be determined.

16. System suitable for determining immunologically-active material in a fluid comprising:

(a) an inert gel matrix containing an electrolyte on a non-reactive support;

(b) means for connecting said matrix with a source of alternating current; and

(c) an alternating current source means.

17. System according to claim 16 wherein the non-reactive support is a plate.

18. System according to claim 16 wherein the inert gel matrix contains an additive decreasing the surface tension.

19. System according to claim 16 wherein the plate is kept in a horizontal level position and the matrix connected by porous bridges to two vessels containing the electrolyte and in contact with the alternating current source via electrodes submerged in the vessels.