US5286624A
Expired / Lapsed
US
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Integral multilayer analytical element for determination of ammonia or ammonia-producing substance
Assignee: Fujifilm Holdings Corp
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Filing: 1991-10-17
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Granted: 1994-02-15
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Expires: 2011-10-17
Abstract
Abstract An integral multilayer analytical element for the determination of ammonia or an ammonia-producing substance comprising a light-transmissive liquid-impermeable support, an indicator layer containing an indicator which produces a detectable change by gaseous ammonia, a liquid permeation barrier layer, a reagent layer containing an alkaline buffer and optionally a reagent capable of reacting with a substance to produce ammonia and a spreading layer laminated in this order, which is improved by that the indicator layer contains a polyvinyl alkyl ether, and/or which is improved by that the surface of said support facing toward the indicator layer is undercoated with a polyvinyl alkyl ether, a hydroxyalkyl cellulose, an alkyl cellulose, polystyrene, a polyalkyl methacrylate, polyviriylidene chloride, polyvinyl alcohol or polyvinyl pyrrolidone, substantially not containing ammonia and ammonium ion. By using the above analytical element, ammonia or an ammonia-producing substance can be analyzed at a high coloring optical density and a high accuracy. The measuring accuracy is further improved by lowering the background optical density.
Inventors
- 👤 Kaoru Terashima
- 👤 Toru Kitani
- 👤 Toshihiro Mori
- 👤 Tsuneo Kawase
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:54
CPC Classifications
G; G01; G01N; G01N31/00; G01N31/22; G01N33/00; G01N33/48; G01N33/50; G01N33/52; G01N33/525; G01N33/526; G01N33/84; Y; Y10; Y10S; Y10S435/00; Y10S435/805
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
85 words
In an integral multilayer analytical element for the determination of ammonia or an ammonia-producing substance comprising a light-transmissive liquid-impermeable support, an indicator layer containing an indicator which produces a detectable change by gaseous ammonia, a liquid permeation barrier layer, a reagent layer containing an alkaline buffer and optionally a reagent capable of reacting with said ammonia-producing substance to produce ammonia, and, a spreading layer, laminated in this order, the improvement which comprises that the indicator layer contains a polyvinyl alkyl ether as a binder polymer.
Claim 2
Dependent Claim
85 words
In an integral multilayer analytical element for the determination of ammonia or an ammonia-producing substance comprising a light-transmissive liquid-impermeable support, an indicator layer containing an indicator which produces a detectable change by gaseous ammonia, a liquid permeation barrier layer, a reagent layer containing an alkaline buffer and optionally a reagent capable of reacting with said ammonia-producing substance to produce ammonia, and, a spreading layer, laminated in this order, the improvement which comprises that the indicator layer contains a polyvinyl alkyl ether as a binder polymer.
Claim 3
Dependent Claim
30 words
The analytical element of claim 1 wherein said polyvinyl alkyl ether is a member selected from the group consisting of polyvinyl methyl ether, polyvinyl ethyl ether and polyvinyl isobutyl ether.
Claim 4
Dependent Claim
115 words
In an integral multilayer analytical element for the determination of ammonia or an ammonia-producing substance comprising a light-transmissive liquid-impermeable support, an indicator layer containing an indicator which produces a detectable change by gaseous ammonia, a liquid permeation barrier layer, a reagent layer containing an alkaline buffer and optionally a reagent capable of reacting with said ammonia-producing substance to produce ammonia and a spreading layer laminated in this order, the improvement which comprises that the surface of said support facing toward the indicator layer is undercoated with a polymer selected from the group consisting of a polyvinyl alkyl ether, a hydroxyalkyl cellulose, an alkyl cellulose, polystyrene, a polyalkyl methacrylate, polyvinylidene chloride, polyvinyl alcohol and polyvinyl pyrrolidone.
Claim 5
Dependent Claim
115 words
In an integral multilayer analytical element for the determination of ammonia or an ammonia-producing substance comprising a light-transmissive liquid-impermeable support, an indicator layer containing an indicator which produces a detectable change by gaseous ammonia, a liquid permeation barrier layer, a reagent layer containing an alkaline buffer and optionally a reagent capable of reacting with said ammonia-producing substance to produce ammonia and a spreading layer laminated in this order, the improvement which comprises that the surface of said support facing toward the indicator layer is undercoated with a polymer selected from the group consisting of a polyvinyl alkyl ether, a hydroxyalkyl cellulose, an alkyl cellulose, polystyrene, a polyalkyl methacrylate, polyvinylidene chloride, polyvinyl alcohol and polyvinyl pyrrolidone.
Claim 6
Dependent Claim
49 words
The analytical element of claim 1 wherein the surface of said support facing toward the indicator layer is undercoated with a polymer selected from the group consisting of a polyvinyl alkyl ether, a hydroxyalkyl cellulose, an alkyl cellulose, polystyrene, a polyalkyl methacrylate, polyvinylidene chloride, polyvinyl alcohol and polyvinyl pyrrolidone.
Claim 7
Dependent Claim
17 words
The analytical element of claim 3 or 4 wherein said surface is undercoated with polyvinyl alkyl ether.
Claim 8
Dependent Claim
30 words
The analytical element of claim 5 wherein said polyvinyl alkyl ether is a member selected from the group consisting of polyvinyl methyl ether, polyvinyl ethyl ether and polyvinyl isobutyl ether.
Claim 9
Dependent Claim
28 words
The analytical element of claim 1, 3 or 4 wherein said liquid permeation barrier layer is an air barrier layer composed of a porous material having continuous voids.
Claim 10
Dependent Claim
28 words
The analytical element of claim 7 wherein said porous material is a membrane filter made of a material selected from the group consisting of polyethylene, polypropylene and polytetrafluoroethylene.
Claim 11
Dependent Claim
25 words
The analytical element of claim 1, 3, or 4, which further comprises an ammonia diffusion-preventing layer comprising a polymer binder placed on the reagent layer.
Claim 12
Dependent Claim
23 words
The analytical element of claim 9 wherein said polymer binder is selected from the group consisting of hydroxyalkyl cellulose, agarose and polyvinyl alcohol.
Claim 13
Dependent Claim
35 words
The analytical element of claim 9 which is for the determination of an ammonia-producing substance and further comprises an endogeneous ammonia-trapping layer containing a reagent composition containing an enzyme of which the substrate is ammonia.
Claim 14
Dependent Claim
19 words
The analytical element of claim 1 wherein the indicator contains 1 to 2% by weight of the binder polymer.
Claim 15
Dependent Claim
21 words
The analytical element of claim 3 wherein the indicating layer is coated with 5 to 500 mg/m 2 of the polymer.
Claim 16
Dependent Claim
87 words
In an integral multilayer analytical element for the determination of ammonia or an ammonia-producing substance consisting essentially of a light-transmissive liquid-impermeable support, an indicator layer containing an indicator which produces a detectable change by gaseous ammonia, a liquid permeation barrier layer, a reagent layer containing an alkaline buffer and optionally a reagent capable of reacting with said ammonia-producing substance to produce ammonia, and, a spreading layer, laminated in this order, the improvement which comprises that the indicator layer contains a polyvinyl alkyl ether as a binder polymer.
Claim 17
Dependent Claim
87 words
In an integral multilayer analytical element for the determination of ammonia or an ammonia-producing substance consisting essentially of a light-transmissive liquid-impermeable support, an indicator layer containing an indicator which produces a detectable change by gaseous ammonia, a liquid permeation barrier layer, a reagent layer containing an alkaline buffer and optionally a reagent capable of reacting with said ammonia-producing substance to produce ammonia, and, a spreading layer, laminated in this order, the improvement which comprises that the indicator layer contains a polyvinyl alkyl ether as a binder polymer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-02-14 | 1997-08-16 | 1998-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-02-14 | 2001-08-16 | 2002-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-02-14 | 2005-08-16 | 2006-02-15 | $7700.00 | Window Closed / Lapsed |