Patent US5709837A successfully refreshed from Google Patents.
US5709837A
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Dry analytical element containing ampholyte
Assignee: Fujifilm Holdings Corp
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Filing: 1995-10-19
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Granted: 1998-01-20
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Expires: 2015-10-19
Abstract
Abstract A dry analytical element comprising at least one water-permeable reagent layer and a porous spreading layer laminated in this order on a support, wherein at least one layer which is the water-permeable reagent layer, the porous spreading layer or an optional water-permeable layer contains a water-soluble polybasic amino carboxylic acid which is an ampholyte. By applying an analytical element of the invention, an analyte can be measured at a high sensitivity using a small amount of an enzyme, etc., and shelf file can be extended.
Inventors
- 👤 Toshihiro Mori
- 👤 Masashi Ogawa
- 👤 Yoshikazu Amano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:54
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/52; G01N33/525; Y; Y10; Y10T; Y10T436/00; Y10T436/14; Y10T436/145555; Y10T436/147777; Y10T436/17; Y10T436/171538
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
72 words
A dry analytical element comprising, laminated in this order, a support, at least one water-permeable reagent layer and a porous spreading layer, wherein at least one layer contains a water-soluble polybasic amino carboxylic acid which is an ampholyte having the formula R--NH--(CH 2 CH 2 --N)-- n H, wherein R is H or --(CH 2 --) m COOH, provided that m is 1 or 2, and n is 3, 4 or 5.
Claim 2
Dependent Claim
72 words
A dry analytical element comprising, laminated in this order, a support, at least one water-permeable reagent layer and a porous spreading layer, wherein at least one layer contains a water-soluble polybasic amino carboxylic acid which is an ampholyte having the formula R--NH--(CH 2 CH 2 --N)-- n H, wherein R is H or --(CH 2 --) m COOH, provided that m is 1 or 2, and n is 3, 4 or 5.
Claim 3
Dependent Claim
34 words
The dry analytical element of claim 1, wherein said n is 5, R is H or --CH 2 CH 2 COOH and the molar ratio of --COOH:--NH-- and --NH 2 is 1:6 to 6:6.
Claim 4
Dependent Claim
36 words
The dry analytical element of claim 1, wherein the layer containing said ampholyte is adjusted so as to have a predetermined pH value in a range of pH 5.0 to 9.5 upon spotting a liquid sample.
Claim 5
Dependent Claim
15 words
The dry analytical element of claim 1, wherein said support is a water-impermeable transparent support.
Claim 6
Dependent Claim
19 words
The dry analytical element of claim 1 which further comprises an additional water-permeable layer, which layer contains the ampholyte.
Claim 7
Dependent Claim
52 words
The dry analytical element of claim 1, wherein said ampholyte is a water-soluble polybasic amino carboxylic acid synthesised by reacting an organic compound having at least two amino or imino groups reacting with a carboxylic acid ester having a carbon-carbon double bond in a nonaqueous solvent, and then hydrolyzing the ester portion.
Claim 8
Dependent Claim
36 words
The dry analytical element of claim 6, wherein the layer containing said ampholyte is adjusted so as to have a predetermined pH value in a range of pH 5.0 to 9.5 upon spotting a liquid sample.
Claim 9
Dependent Claim
15 words
The dry analytical element of claim 6, wherein said support is a water-impermeable transparent support.
Claim 10
Dependent Claim
54 words
The dry analytical element of claim 6, which consists essentially of a water-impermeable transparent support, an indicator layer, a porous liquid barrier layer, an ammonia-producing reagent layer, an ammonia diffusion-preventing layer, an endogeneous ammonia-trapping layer, and the spreading layer integrally laminated in this order, wherein said ampholyte is incorporated into the endogeneous ammonia-trapping layer.
Claim 11
Dependent Claim
23 words
The dry analytical element of claim 8, wherein a reagent composition for the detection of creatinine is incorporated into the ammonia-producing reagent layer.
Claim 12
Dependent Claim
31 words
The dry analytical element of claim 1 comprising at least one water-permeable reagent layer and a porous spreading layer for spreading whole blood wherein the spreading layer contains a hemolytic reagent.
Claim 13
Dependent Claim
31 words
The dry analytical element of claim 11 which contains a reagent composition for determination of a member selected from the group consisting of creatinine, urea nitrogen, inorganic phosphorus and bicarbonate salts.
Claim 14
Dependent Claim
20 words
The dry analytical element of claim 11 which contains a reagent composition for the determination of creatinine or urea nitrogen.
Claim 15
Dependent Claim
14 words
The dry analytical element of claim 11, wherein said hemolytic reagent is a surfactant.
Claim 16
Dependent Claim
20 words
The dry analytical element of claim 14, wherein the content of said surfactant is 1 to 50 g/m 2 .
Claim 17
Dependent Claim
20 words
The dry analytical element of claim 14, wherein the content of said surfactant is 1 to 50 g/m 2 .
Claim 18
Dependent Claim
14 words
The dry analytical element of claim 14, wherein said surfactant is a nonionic surfactant.
Claim 19
Dependent Claim
13 words
The dry analytical element of claim 17, wherein said nonionic surfactant is alkylphenoxypolyethoxyethanol.
Claim 20
Dependent Claim
89 words
A dry analytical element which consists essentially of a water-impermeable transparent support, an indicator layer, a porous liquid barrier layer, an ammonia-producing reagent layer, an ammonia diffusion-preventing layer, an endogenous ammonia-trapping layer, and a spreading layer, integrally laminated in this order, and having an ampholyte having the formula R--NH.paren open-st.CH 2 CH 2 --N.paren close-st. n H, wherein R is H or .paren open-st.CH 2 .paren close-st. m COOH, provided that m is 1 or 2, and n is 3, 4 or 5 incorporated into the endogenous ammonia-trapping layer.
Claim 21
Dependent Claim
89 words
A dry analytical element which consists essentially of a water-impermeable transparent support, an indicator layer, a porous liquid barrier layer, an ammonia-producing reagent layer, an ammonia diffusion-preventing layer, an endogenous ammonia-trapping layer, and a spreading layer, integrally laminated in this order, and having an ampholyte having the formula R--NH.paren open-st.CH 2 CH 2 --N.paren close-st. n H, wherein R is H or .paren open-st.CH 2 .paren close-st. m COOH, provided that m is 1 or 2, and n is 3, 4 or 5 incorporated into the endogenous ammonia-trapping layer.
Claim 22
Dependent Claim
23 words
The dry analytical element of claim 19, wherein a reagent composition for the detection of creatinine is incorporated into the ammonia-producing reagent layer.
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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) | 2001-01-19 | 2001-07-21 | 2002-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-01-19 | 2005-07-21 | 2006-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-01-19 | 2009-07-21 | 2010-01-20 | $7700.00 | Window Closed / Lapsed |