Multilayer analysis sheet for analyzing liquid samples

• US 4,292,272 A
• Filed: 06/09/1980
• Issued: 09/29/1981
• Est. Priority Date: 06/08/1979
• 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): Serwin, Ronald
• Application Number:
  US06/157,737
• Time in Patent Office: 477 Days
• Field of Search: 422/56, 422/57, 422/58, 422/66
• US Class Current: 422/428
• CPC Class Codes: G01N 33/525 Multi-layer analytical elements

Abstract

A multilayer analysis sheet for analyzing liquid samples is described, comprising, in sequence, a light transmitting hydrophobic support having on one side thereof at least one layer containing at least one reagent in a binder and a liquid sample spreading layer made of fabric, which layers are laminated to form an integral unit together with the support, wherein said fabric has the ability to supply a liquid sample placed on the surface thereof to the reagent-containing layer at a substantially constant volume per unit area, which ability is conferred upon the fabric by rendering it hydrophilic; the multilayer analysis sheet can be economically manufactured without variations in quality, and improves the spreading capability of liquid samples.

Claims

1. A multilayer analysis sheet for analyzing liquid samples comprising, in sequence, a light transmitting water-impermeable support having on one side thereof at least one layer containing at least one reagent in a binder, and a liquid sample spreading layer made of fabric, said layers being laminated to form an intergral unit together with the support, and wherein said fabric has the ability to supply a liquid sample placed on the surface thereof to said reagent-containing layer at a substantially constant volume per unit area, which ability is conferred upon said fabric by rendering it hydrophilic.

2. A multilayer analysis sheet as in claim 1, wherein said fabric has the characteristic that the spreading of a 7% cattle albumin aqueous solution on the fabric is 30 seconds or less.

3. A multilayer analysis sheet as in claim 2, wherein said fabric has the characteristic that the spreading of the 7% cattle albumin aqueous solution is 15 seconds or less.

4. A multilayer analysis sheet as in claim 2, wherein said fabric has the characteristic that the spreading of 7% cattle albumin aqueous solution is 10 seconds or less.

5. A multilayer analysis sheet as in claim 1, wherein said fabric is rendered hydrophilic by the steps of washing with water and contacting with an aqueous solution containing from 1 to 5% surface active agent.

6. A multilayer analysis sheet as in claim 1, wherein said fabric contains from about 0.05 to 10% by weight of a hydrophilic polymer.

7. A multilayer analysis sheet as in claim 6, wherein the fabric contains from about 0.1 to 5% by weight of the hydrophilic polymer.

8. A multilayer analysis sheet as in claim 1, 2, 3, or 4, wherein said sheet comprises an analytical function supporting layer containing a water-permeable hydrophilic polymer binder between said sample spreading layer and said layer containing at least one reagent in a binder.

9. A multilayer analysis sheet as in claim 8, wherein said analytical function supporting layer is a radiation-blocking layer or a light reflecting layer.

10. A multilayer analysis sheet as in claim 9, wherein said sheet includes a structural auxiliary layer containing a water-permeable hydrophilic polymer binder between said sample spreading layer and said analytical function supporting layer.

11. A multilayer analysis sheet as in claim 10, wherein said structural auxiliary layer is an adhesive layer.

12. A multilayer analysis sheet as claimed in claim 1, wherein said binder is a water-permeable hydrophilic polymer binder, and further wherein said liquid sample is a liquid sample containing water as a solvent.

13. A multilayer analysis sheet as claimed in claim 1, wherein said fabric is formed by weaving warp and weft yarns in a plain weave, wherein the count of said weave ranges between 20 and 120.

14. A multilayer analysis sheet as claimed in any of claims 1 or 12, wherein said fabric is selected from the group consisting of canequim, broadcloth, kapok, flax, hemp, ramie, silk, viscose rayon, cupro-ammonium rayon, cellulose acetate, vinylon and polyethylene terephthalate.

15. A multilayer analysis sheet as claimed in any of claims 1, 2, 3 or 4, wherein said sheet is further comprised of an analytical function supporting layer containing a water-permeable hydrophilic polymer binder between said sample spreading layer and said layer containing at least one reagent in a binder, and wherein said analytical function supporting layer is a radiation-blocking layer or a light-reflecting layer;

said sheet further comprising a structural auxiliary layer containing a water-permeable hydrophilic polymer binder between said sample spreading layer and said analytical function supporting layer.

16. A multilayer analysis sheet as claimed in any of claims 1, 2, 3 or 4, wherein said structural auxiliary layer is an adhesive layer.