Multi-layer analysis element utilizing specific binding reaction

• US 4,587,102 A
• Filed: 08/02/1984
• Issued: 05/06/1986
• Est. Priority Date: 06/05/1981
• Status: Expired due to Term

• Current Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Okazaki, Masaki, Yasuda, Yukio, Nagatomo, Shigeru, Masuda, Nobuhito, Makiuchi, Hajime
• Primary Examiner(s): NOT, DEFINED
• Application Number:
  US06/637,324
• Time in Patent Office: 642 Days
• Field of Search: 422/56, 422/57, 422/58, 436/810, 435/7, 435/805
• US Class Current: 422/421
• CPC Class Codes: G01N 33/525 Multi-layer analytical elements
• CPC Class Codes: G01N 33/54386 Analytical elements
• CPC Class Codes: Y10S 435/805 Test papers
• CPC Class Codes: Y10S 436/81 Tube, bottle, or dipstick

Abstract

A dry type multilayer analysis element for assaying a concentration of a specific component utilizing a competitive immunological reaction comprises a detection element comprising a detection layer which receives a labelled complex formed as a result of the competitive immunological reaction or an optically detectable change formed dependent upon an amount of the labelled complex of the specific component and having further provided thereon the detection layer a reaction layer comprising a fibrous porous medium containing fine particles therein. The multilayer analysis element absorbs an amount of a sample solution necessary for the competitive immunological reaction so that the multilayer analysis element has high sensitivity and high reproducibility.

Claims

1. A multilayer analysis element for assaying a concentraion of a specific component in an aqueous medium utilizing a competitive reaction in the presence of a predetermined amount of a protein to be specifically bound to a specific component and a specific component labeled with a labeling substance which is capable of reacting with said protein to be specifically bound to said specific component,

the multilayer analysis element comprising:

(A) a reaction element comprising a fibrous porous medium having a water-retention capability of at least 25 μ

l and fine particles of a high molecular weight material having a particle size of about 1 μ

m to about 1 mm which contains a protein to be specifically bound to a specific component to be assayed but does not substantially contain any specific component having binding capability to the protein, whereby when a sample solution is applied to said reaction element it is absorbed and retained in said reaction element for a time period sufficient for a competitive reaction to occur in the reaction element; and

having further provided in fluid communication with said reaction element,

(B) a detection element comprising a detection layer which receives a labeled specific component unbound to said protein as a result of said competitive reaction or an optically detectable signal formed dependent on the amount of said labeled specific component.

2. The multilayer analysis element as claimed in claim 1 wherein said reaction element functions to optically block components interfering with optical measurement.

3. The multilayer analysis element as claimed in claim 1 wherein said protein capable of specifically binding to said specific component is not chemically bound to said fibrous porous medium layer.

4. The multilayer analysis element as claimed in claim 1 wherein a reagent layer comprising a porous medium having incorporated therein a labelled complex is further provided on the side opposite said detection layer to said reaction element.

5. The multilayer analysis element as claimed in claim 1 wherein the fibrous porous medium is capable of absorbing at least 50 to 200 μ

l of a sample solution for competitive immunological reaction.

6. The multilayer analysis element as claimed in claim 1 wherein said reaction element has an area smaller than that of said detection element and which is laminated on said detection element so as not to project from said detection element.

7. The multilayer analysis element as claimed in claim 1 or 2 wherein said specific component and said protein capable of specifically binding thereto is a protein capable of specifically binding so as to form a pair caused by an immunological reaction.

8. The multilayer analysis element as claimed in claim 1 wherein said fine particles are independently separated.

9. The multilayer analysis element as claimed in claim 8 wherein said reaction element has a predetermined area and is prepared by freeze drying a fibrous porous medium containing a predetermined amount of a protein capable of specifically binding to said specific component.

10. the multilayer analysis element as claimed in claim 1 wherein a light shielding layer for optically blocking components interfering with optical measurement is provided between said detection layer and said reaction element.

11. The multilayer analysis element as claimed in claim 10 wherein said light shielding layer is a light reflection layer.

12. The multilayer analysis element as claimed in claim 10 wherein said light shielding layer is a light absorption layer for excitation wavelength and/or fluorescent emission.