US4273636A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Selective chemical sensitive field effect transistor transducers
Assignee: Nihon Kohden Corp
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Filing: 1978-05-19
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Granted: 1981-06-16
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Expires: 1998-05-19
Abstract
Abstract A chemical sensitive field effect transistor transducer is provided having a semipermeable membrane on the surface of a chemical selective system overlying an insulated gate field effect transistor. Such a field effect transistor transducer is effective for the measurement of chemical constituents of factory waste water containing micro-particles, saliva or blood containing proteins, etc., where conventional devices give unreliable results.
Inventors
- 👤 Kiyoo Shimada
- 👤 Makoto Yano
- 👤 Kyoichiro Shibatani
- 👤 Tsutomu Makimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:47
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/403; G01N27/414; Y; Y10; Y10S; Y10S435/00; Y10S435/817
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
89 words
A selective chemically sensitive FET transducer which selectively detects specific chemical substances to which the transducer is exposed, which comprises: an FET transducer whose gate region is overlayed with a chemically selective sensitive membrane, which reacts or interacts with a specific chemical substance(s) and which is provided with a semipermeable membrane having a water content greater than 10% overlying said chemically selective sensitive membrane, said semipermeable membrane consisting of a hydrophillic membrane material(s) or a hydrophobic membrane material(s), each of said maerial(s) containing a light darkening dye or pigment.
Claim 2
Dependent Claim
89 words
A selective chemically sensitive FET transducer which selectively detects specific chemical substances to which the transducer is exposed, which comprises: an FET transducer whose gate region is overlayed with a chemically selective sensitive membrane, which reacts or interacts with a specific chemical substance(s) and which is provided with a semipermeable membrane having a water content greater than 10% overlying said chemically selective sensitive membrane, said semipermeable membrane consisting of a hydrophillic membrane material(s) or a hydrophobic membrane material(s), each of said maerial(s) containing a light darkening dye or pigment.
Claim 3
Dependent Claim
33 words
The transducer of claim 1, wherein said semipermeable membrane is prepared by dissolving or dispersing a light darkening dye or pigment in the polymer or monomer soluion from which said membrane is cast.
Claim 4
Dependent Claim
11 words
The transducer of claim 2, wherein said pigment is carbon black.
Claim 5
Dependent Claim
23 words
The transducer of claim 1, wherein said semipermeable membrane is dyed after it has been cast on said surface of the gate region.
Claim 6
Dependent Claim
93 words
A selective chemically sensitive FET transductor which selectively detects specific chemical substances to which the transducor is exposed, which comprises: an FET transducer whose gate region is overlayed with a chemically selective sensitive membrane, which reacts or interacts with a specific chemical substance(s) and which is provided with a semipermeable membrane having a water content greater than 10%, overlying said chemically selective sensitive membrane, said semipermeable membrane being formed of a hydrophilic material selected from the group consisting of a polymethacrylate, a polyacrylate, a polyacrylamide, a polyvinylpyrrolidone, a polyvinyl alcohol and copolymers thereof.
Claim 7
Dependent Claim
93 words
A selective chemically sensitive FET transductor which selectively detects specific chemical substances to which the transducor is exposed, which comprises: an FET transducer whose gate region is overlayed with a chemically selective sensitive membrane, which reacts or interacts with a specific chemical substance(s) and which is provided with a semipermeable membrane having a water content greater than 10%, overlying said chemically selective sensitive membrane, said semipermeable membrane being formed of a hydrophilic material selected from the group consisting of a polymethacrylate, a polyacrylate, a polyacrylamide, a polyvinylpyrrolidone, a polyvinyl alcohol and copolymers thereof.
Claim 8
Dependent Claim
20 words
The transducer of claim 1 or 5, wherein the thickness of said semipermeable membrane is between 0.1μ and 5 mm.
Claim 9
Dependent Claim
35 words
The transducer of claim 1 or 5, wherein the average optical density of said semipermeable membrane using light of 350 nm to 700 nm wavelength is more than 0.7 when measured perpendicular to the surface.
Claim 10
Dependent Claim
13 words
The transducer of claim 1 or 5, wherein said semipermeable membrane is heparinized.
Claim 11
Dependent Claim
34 words
The transducer of claim 1, wherein said semipermeable membrane is formed of a hydrophilic material selected from the group consisting of a polymethacrylate, a polyacrylate, a polyacrylamide, a polyvinylpyrrolidone, a polyvinylalcohol and copolymers thereof.
Claim 12
Dependent Claim
16 words
The transducer of claim 5 or 9, wherein said membrane is a hydrogel containing 20-90% water.
Claim 13
Dependent Claim
15 words
The transducer of claim 5 or 9, wherein said semipermably membrane material is poly-β-hydroxyethyl methacrylate.
Claim 14
Dependent Claim
102 words
The transducer of claim 5 or 9, wherein the said semipermeable membrane material is a copolymer formed from β-hydroxyethylmethacrylate and comonomers selected from the group consisting of hydroxypropyl acrylate, acrylate or methacrylate esters having the formuls CH 2 ═C(R)COO-(CH 2 CH 2 O) n R', wherein R is H or CH 3 and R' is aryl, alkyl, --CH 2 CH 2 OH, --NH 2 , --NHCH 3 m -N(CH 3 ) 2 , --N(CH 3 ) 3 +, and n is an integer, styrene, methyl methacrylate ethylene glycol dimethacrylate, glycidyl methacrylate, and graft copolymers of poly-styrene or poly-methyl methacrylate on poly-β-hydroxyethyl methacrylate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-06-15 | 1984-12-15 | 1985-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-15 | 1988-12-15 | 1989-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-15 | 1992-12-15 | 1993-06-16 | $7700.00 | Window Closed / Lapsed |