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Patent US4889797A successfully refreshed from Google Patents.
US4889797A
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Dry analytical element having a spread control area for assaying enzyme activity
Assignee: Fujifilm Holdings Corp
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Filing: 1987-05-26
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Granted: 1989-12-26
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Expires: 2007-05-26
Abstract
Abstract A dry analytical element for assaying an enzyme in a liquid is disclosed, comprising a support having provided thereon at least a porous liquid-spreading layer composed of water non-absorbent fibers, wherein said porous liquid-spreading layer contains a substrate for an enzyme to be assayed and a hydrophilic polymer in an amount effective to decrease a spreading area by at least 20%. The analytical element exhibits high sensitivity and high reproducibility.
Inventors
- 👤 Yoshikazu Amano
- 👤 Shigeki Kageyama
- 👤 Harumi Katsuyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:38
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/52; C; C12; C12Q; C12Q1/00; C12Q1/26; C12Q1/32; C12Q1/34; C12Q1/40; C12Q1/42; C12Q1/48; Y; Y10; Y10S; Y10S435/00; Y10S435/805; Y10S435/81; Y10S436/00; Y10S436/807; Y10S436/808; Y10S436/81
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
147 words
A dry analytical element for assaying an enzyme activity in a liquid, which comprises a support having provided thereon at least a porous liquid-spreading layer composed of water non-absorbent fibers, wherein said porous liquid-spreading layer contains a substrate for an enzyme to be assayed and at least one water soluble hydrophilic polymer in an amount effective to decrease the spreading area of said porous liquid-spreading layer by at least 20%, wherein said hydrophilic polymer is selected from the group consisting of a polymer comprising a repeating unit represented by formula (I) ##STR8## wherein R 1 represent a hydrogen atom or a lower alkyl group; and R 2 and R 3 each represents a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon residue; a substituted or unsubstituted aromatic hydrocarbon residue, or a substituted or unsubstituted heterocyclic group, or R 2 and R 3 taken together form a ring.
Claim 2
Dependent Claim
147 words
A dry analytical element for assaying an enzyme activity in a liquid, which comprises a support having provided thereon at least a porous liquid-spreading layer composed of water non-absorbent fibers, wherein said porous liquid-spreading layer contains a substrate for an enzyme to be assayed and at least one water soluble hydrophilic polymer in an amount effective to decrease the spreading area of said porous liquid-spreading layer by at least 20%, wherein said hydrophilic polymer is selected from the group consisting of a polymer comprising a repeating unit represented by formula (I) ##STR8## wherein R 1 represent a hydrogen atom or a lower alkyl group; and R 2 and R 3 each represents a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon residue; a substituted or unsubstituted aromatic hydrocarbon residue, or a substituted or unsubstituted heterocyclic group, or R 2 and R 3 taken together form a ring.
Claim 3
Dependent Claim
169 words
A dry analytical element for assaying an enzyme activity in a liquid, which comprises a support having provided thereon at least a porous liquid-spreading layer composed of water non-absorbent fibers, wherein said porous liquid-spreading layer contains a substrate for an enzyme to be assayed and at least one water soluble hydrophilic polymer in an amount effective to decrease the spreading area of said porous liquid-spreading layer by at least 20%, wherein said hydrophilic polymer is a polymer comprising a repeating unit represented by formula (II) ##STR9## wherein R 4 represents a hydrogen atom or a lower alkyl group; and Q represents: ##STR10## wherein q represents an integer of from 2 to 4, --NR 5 --CO--R 6 , wherein R 5 represents an alkyl group having from 1 to 4 carbon atoms, and R 6 represents a hydrogen atom or an alkyl group having from 1 to 4 carbon atoms; or ##STR11## wherein Z 1 represents an atomic group forming a lactam ring, an oxazolidone ring or a pyridone ring.
Claim 4
Dependent Claim
169 words
A dry analytical element for assaying an enzyme activity in a liquid, which comprises a support having provided thereon at least a porous liquid-spreading layer composed of water non-absorbent fibers, wherein said porous liquid-spreading layer contains a substrate for an enzyme to be assayed and at least one water soluble hydrophilic polymer in an amount effective to decrease the spreading area of said porous liquid-spreading layer by at least 20%, wherein said hydrophilic polymer is a polymer comprising a repeating unit represented by formula (II) ##STR9## wherein R 4 represents a hydrogen atom or a lower alkyl group; and Q represents: ##STR10## wherein q represents an integer of from 2 to 4, --NR 5 --CO--R 6 , wherein R 5 represents an alkyl group having from 1 to 4 carbon atoms, and R 6 represents a hydrogen atom or an alkyl group having from 1 to 4 carbon atoms; or ##STR11## wherein Z 1 represents an atomic group forming a lactam ring, an oxazolidone ring or a pyridone ring.
Claim 5
Dependent Claim
71 words
The dry analytical element of claim 2, wherein R 1 represents a hydrogen atom or a methyl group; and R 2 and R 3 each represents a hydrogen atom, a methyl group, an ethyl group, a benzyl group, a hydroxyethyl group, a cyclohexyl group, a phenyl group, a piperidino group or a morpholino group, with the total number of carbon atoms in R 2 and R 3 being up to 12.
Claim 6
Dependent Claim
63 words
The dry analytical element of claim 2, wherein R 4 is a hydrogen atom; and Q represents: ##STR12## wherein R 5 represents a methyl group or an ethyl group, and R 6 represents a hydrogen atom, a methyl group or an ethyl group; or ##STR13## wherein Z 1 represents an atomic group forming a 5- or 6-membered lactam ring or an oxazolidone ring.
Claim 7
Dependent Claim
19 words
The dry analytical element of claim 4, wherein Q repressents a pyrrolidone residual group or an oxazolidone residual group.
Claim 8
Dependent Claim
30 words
The dry analytical element of claim 1, wherein said polymer comprising the repeating unit of formula (I) contains at least 20 mol % of said repeating unit of formula (I).
Claim 9
Dependent Claim
38 words
The dry analytical element of claim 2, wherein said polymer comprising the repeating unit of formula (I) or (II) is present in an amount of from 2 g to 15 g per m 2 of the liquid-spreading layer.
Claim 10
Dependent Claim
30 words
The dry analytical element of claim 1 wherein said polymer comprising the repeating unit of formula (I) contains at least 50 mol % of said repeating unit of formula (I).
Claim 11
Dependent Claim
35 words
The dry analytical element of claim 1 wherein said polymer comprising the repeating unit of formula (I) is present in an amount of from 2 to 15 g per m 2 of the liquid-developing layer.
Claim 12
Dependent Claim
30 words
The dry analytical element of claim 2 wherein said polymer comprising the repeating unit of formula (II) contains at least 20 mol % of said repeating unit of formula (II).
Claim 13
Dependent Claim
30 words
The dry analytical element of claim 2 wherein said polymer comprising the repeating unit of formula (II) contains at least 50 mol % of said repeating unit of formula (II).
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1992-12-25 | 1993-06-26 | 1993-12-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-12-25 | 1997-06-26 | 1997-12-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-12-25 | 2001-06-26 | 2001-12-26 | $7700.00 | Window Closed / Lapsed |