US4909921A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrochemical sensor facilitating repeated measurement
Assignee: NEC Corp
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Filing: 1989-02-09
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Granted: 1990-03-20
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Expires: 2009-02-09
Abstract
Abstract An electrochemical sensor wherein a FET for measuring chemical substances and a reference electrode are covered with a continuous hydrous polymer on an insulating substrate, and on the hydrous polymer, an enzyme-immobilized film is formed in a region positioned on a channel part of FET for measuring chemical substances.
Inventors
- 👤 Narushi Ito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:15
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/001; G; G01; G01N; G01N27/00; G01N27/26; G01N27/403; G01N27/414; G01N27/4145; Y; Y10; Y10S; Y10S435/00; Y10S435/817
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
66 words
An electrochemical sensor comprising: a substrate having an insulative surface; FET for measurement formed on said substrate and having a source, a drain, a channel portion and an enzyme-immobilized film disposed above said channel portion; a reference electrode formed adjacently to said FET for measurement on said substrate; and a hydrous polymer continuously covering said channel portion of said FET for measurement and said reference electrode.
Claim 2
Dependent Claim
66 words
An electrochemical sensor comprising: a substrate having an insulative surface; FET for measurement formed on said substrate and having a source, a drain, a channel portion and an enzyme-immobilized film disposed above said channel portion; a reference electrode formed adjacently to said FET for measurement on said substrate; and a hydrous polymer continuously covering said channel portion of said FET for measurement and said reference electrode.
Claim 3
Dependent Claim
29 words
An electrochemical sensor according to claim 1, wherein said hydrous polymer is constituted by a substance selected from a group consisting of albumin, agar, gelatin, alginic acid and K-carrageenan.
Claim 4
Dependent Claim
26 words
An electrochemical sensor according to claim 2, wherein said enzyme-immobilized film is formed on said hydrous polymer on said channel portion of said FET for measurement.
Claim 5
Dependent Claim
36 words
An electrochemical sensor according to claim 3, wherein a FET for comparison is further provided adjacently to said reference electrode on said substrate, said hydrous polymer being so formed as to cover said FET for comparison.
Claim 6
Dependent Claim
26 words
An electrochemical sensor according to claim 1, wherein said enzyme-immobilized film is formed on said hydrous polymer on said channel portion of said FET for measurement.
Claim 7
Dependent Claim
88 words
An electrochemical sensor having: an insulative substrate; a reference electrode formed on said insulative substrate; first and second semiconductor layers formed adjacently to said reference electrode on said insulative substrate; source and drain electrodes formed on the respective opposite sides of said first and second semiconductor layers; an insulating film covering the respective surfaces of said first and second semiconductor layers; a hydrous polymer covering said insulating film and said reference electrode commonly; and an enzyme-immobilized film formed selectively on said hydrous polymer on said first semiconductor layer.
Claim 8
Dependent Claim
88 words
An electrochemical sensor having: an insulative substrate; a reference electrode formed on said insulative substrate; first and second semiconductor layers formed adjacently to said reference electrode on said insulative substrate; source and drain electrodes formed on the respective opposite sides of said first and second semiconductor layers; an insulating film covering the respective surfaces of said first and second semiconductor layers; a hydrous polymer covering said insulating film and said reference electrode commonly; and an enzyme-immobilized film formed selectively on said hydrous polymer on said first semiconductor layer.
Claim 9
Dependent Claim
29 words
An electrochemical sensor according to claim 6, wherein said hydrous polymer is constituted by a substance selected from a group consisting of albumin, agar, gelatin, alginic acid and K-carrageenan.
Claim 10
Dependent Claim
23 words
An electrochemical sensor according to claim 7, wherein said first and second semiconductor layers are different in a conductivity type from each other.
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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) | 1993-03-19 | 1993-09-18 | 1994-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-19 | 1997-09-18 | 1998-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-19 | 2001-09-18 | 2002-03-20 | $7700.00 | Window Closed / Lapsed |