Multi-layer chemical analytical materials

• US 4,356,149 A
• Filed: 07/02/1980
• Issued: 10/26/1982
• Est. Priority Date: 07/02/1979
• 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: Arai, Fuminori, Kitajima, Masao, Kondo, Asaji
• Primary Examiner(s): Turk, Arnold
• Application Number:
  US06/165,444
• Time in Patent Office: 846 Days
• Field of Search: 422/56, 422/57, 23/230 B, 435/805, 435/12
• US Class Current: 422/423
• CPC Class Codes: C12Q 1/58 involving urea or urease
• CPC Class Codes: G01N 33/526 the element being adapted for a specific analyte
• CPC Class Codes: Y10S 435/805 Test papers

Abstract

A multi-layer chemical analytical material comprising a support, a reagent layer on the support and a spreading layer on the reagent layer wherein the reagent layer is composed of a hydrophilic binder and fine hydrophobic particles dispersed in the hydrophilic binder, said hydrophobic particles containing a reagent capable of directly or indirectly reacting with the component being analyzed to produce a color change.

Claims

1. A multi-layer chemical analytical material comprising

a light-transmitting and water-impermeable support,

a reagent layer on the support and

an aqueous liquid sample-spreading layer on the reagent layer,

wherein the reagent layer is composed of a hydrophilic binder having hydrophobic fine particles dispersed therein, said particles being water impermeable containing a reagent capable of directly or indirectly reacting with a component to be determined to provide a color change and wherein there is substantially no exposure of the reagent on the surface of said hydrophobic fine particles.

2. The material as claimed in claim 1 wherein the hydrophilic binder contains a second reagent capable of reacting with the component to be determined.

3. The material as claimed in claim 1 or 2 wherein said hydrophobic fine particles are oily minute particles prepared by adding a lipophilic binder polymer to an oily matter prepared by dissolving the reagent in an organic solvent substantially incompatible with water.

4. The material as claimed in claim 1 or 2 wherein said hydrophobic fine particles are oily minute particles prepared by dissolving in an organic solvent substantially incompatible with water, a polymer soluble in an organic solvent, and dissolving or dispersing the reagent in the resulting solution.

5. The material as claimed in claim 3 wherein said hydrophobic fine particles are microcapsules prepared by encapsulating said oily minute particles with a thin layer of a lipophilic polymer or a hydrophilic polymer.

6. The material as claimed in claim 1 or 2 wherein said spreading layer is a nonfibrous isotropically porous material.

7. The material as claimed in claim 1 or 2 wherein said spreading layer is a fabric having been made hydrophilic.

8. The material claimed in claim 1 or 2 wherein said reagent dispersed in said hydrophobic fine particles is a reagent to detect urea.

9. The material as claimed in claim 1 or 2 wherein the hydrophilic binder in said reagent layer is selected from the group consisting of water-soluble proteins, vegetable gums, and water-soluble synthetic polymers.

10. The material as claimed in claim 1 or 2 wherein said reagent layer is about 0.5 μ

m to about 50 μ

m thick.

11. The material as claimed in claim 1 or 2 wherein said hydrophobic fine particles are minute particles prepared by pulverizing a solid polymer containing the reagent.

12. The material as claimed in claim 11 wherein said hydrophobic fine particles are minute particles with a thin layer of a hydrophilic polymer or a hydrophobic polymer.