Patent US5326449A successfully refreshed from Google Patents.
US5326449A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite membrane
Assignee: Hospira Inc
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Filing: 1993-08-19
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Granted: 1994-07-05
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Expires: 2013-08-19
Abstract
Abstract A sensor device for measuring the concentration of an analyte in solution is described. The device includes a composite membrane which incorporates a porous membrane containing an immobilized biologically-active protein and at least one other membrane. The other membrane may optionally be a blocking membrane, partly embedded in the porous membrane, which is adapted to exclude low molecular weight interfering species such as ascorbic acid. The other membrane may optionally be a protecting membrane which is useful for preventing high molecular species from fouling the porous membrane. Both a blocking membrane and a protecting membrane may be included in the composite membrane, simultaneously. The composite membrane is attached and reliably sealed to a housing by means of ultrasonic welding. These features operate synergistically so that the device exhibits relatively fast response and recovery times, is reliably leak-proof, and may be constructed in relatively small sizes. A method of manufacturing the composite membrane is also provided.
Inventors
- 👤 David D. Cunningham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 04:58
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/001; C12Q1/002; Y; Y10; Y10S; Y10S435/00; Y10S435/817
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
190 words
A device for measuring the concentration of an analyte in a solution, which comprises: (a) an electrically insulating housing which defines a first aperture, a second aperture, and a passage that extends from the first aperture through the housing to the second aperture and which is impervious to a solution that contains an analyte selectively catalyzed by an enzyme; (b) means for conducting electrical current which extend through the first aperture into the passage and are sealed against the first aperture in a manner that prevents fluid flow; and (c) a composite membrane located across the passage and ultrasonically welded to the housing so that the solution must pass to the second aperture through the composite membrane to contact the means for conducting electrical current, said composite membrane having a porous membrane which is co-extensive with the composite membrane and which includes an internal surface defining micropores; a biologically active material immobilized within the micropores of the porous membrane; a blocking membrane having a portion which is embedded in the porous membrane within the micropores; and a planar protecting membrane covering the enzyme membrane and ultrasonically welded to the housing.
Claim 2
Independent Claim
190 words
A device for measuring the concentration of an analyte in a solution, which comprises: (a) an electrically insulating housing which defines a first aperture, a second aperture, and a passage that extends from the first aperture through the housing to the second aperture and which is impervious to a solution that contains an analyte selectively catalyzed by an enzyme; (b) means for conducting electrical current which extend through the first aperture into the passage and are sealed against the first aperture in a manner that prevents fluid flow; and (c) a composite membrane located across the passage and ultrasonically welded to the housing so that the solution must pass to the second aperture through the composite membrane to contact the means for conducting electrical current, said composite membrane having a porous membrane which is co-extensive with the composite membrane and which includes an internal surface defining micropores; a biologically active material immobilized within the micropores of the porous membrane; a blocking membrane having a portion which is embedded in the porous membrane within the micropores; and a planar protecting membrane covering the enzyme membrane and ultrasonically welded to the housing.
Claim 3
Dependent Claim
20 words
The device of claim 1 wherein the porous membrane is a porous pre-activated membrane comprising a polyamide or polyvinylidine difluoride.
Claim 4
Dependent Claim
26 words
The device of claim 1 wherein a portion of the means for conducting electrical current is coated with a modified graphite layer containing a thiazine dye.
Claim 5
Dependent Claim
11 words
The device of claim 1 wherein the protein is glucose oxidase.
Claim 6
Dependent Claim
10 words
The device of claim 1 wherein the protein is urease.
Claim 7
Dependent Claim
11 words
The device of claim 1 wherein the protein is creatinine deiminase.
Claim 8
Independent Claim
174 words
A device for measuring the concentration of an analyte in a solution, which comprises: (a) an electrically insulating housing which defines a first aperture, a second aperture, and a passage that extends from the first aperture through the housing to the second aperture and which is impervious to a solution that contains an analyte selectively catalyzed by an enzyme; (b) means for conducting electrical current which extend through the first aperture into the passage and are sealed against the first aperture in a manner that prevents fluid flow; and (c) a composite membrane located across the passage and ultrasonically welded to the housing so that the solution must pass to the second aperture through the composite membrane to contact the means for conducting electrical current, said composite membrane having a porous membrane which is co-extensive with the composite membrane and which includes an internal surface defining micropores; a protein immobilized within the micropores of the porous membrane; and a blocking membrane having a portion which is embedded in the porous membrane within the micropores.
Claim 9
Independent Claim
174 words
A device for measuring the concentration of an analyte in a solution, which comprises: (a) an electrically insulating housing which defines a first aperture, a second aperture, and a passage that extends from the first aperture through the housing to the second aperture and which is impervious to a solution that contains an analyte selectively catalyzed by an enzyme; (b) means for conducting electrical current which extend through the first aperture into the passage and are sealed against the first aperture in a manner that prevents fluid flow; and (c) a composite membrane located across the passage and ultrasonically welded to the housing so that the solution must pass to the second aperture through the composite membrane to contact the means for conducting electrical current, said composite membrane having a porous membrane which is co-extensive with the composite membrane and which includes an internal surface defining micropores; a protein immobilized within the micropores of the porous membrane; and a blocking membrane having a portion which is embedded in the porous membrane within the micropores.
Claim 10
Dependent Claim
20 words
The device of claim 1 wherein the porous membrane is a porous pre-activated membrane comprising a polyamide or polyvinylidine difluoride.
Claim 11
Dependent Claim
20 words
The device of claim 1 wherein the composite membrane is formed in the shape of a flat and thin sheet.
Claim 12
Dependent Claim
197 words
A reusable biosensor device for measuring the concentration of a protein-catalyzed reagent in solution, which comprises: (a) an electrically conducting pin having one or more side surfaces, a transmitting surface, and a receiving surface; (b) a nonporous, electrically insulating housing which is impervious to the solution, covers only the side surfaces, and extends beyond the side surfaces so as to define a well that is adjacent the receiving surface; (c) an ionophore gel inside the well; and (d) a composite membrane located across the well and spaced from the pin, ultrasonically welded to the housing so that the composite membrane, the housing, and the receiving surface completely surround the ionophore gel and so that the solution must pass through the composite membrane to contact the ionophore gel; said composite membrane including a porous membrane co-extensive with the composite membrane and having a larger surface area than the cross-sectional area of the well as measured opposite the composite membrane and having an internal surface which defines micropores; a protein immobilized within the porous membrane; and a planar protecting membrane ultrasonically welded to the housing which covers the composite membrane and presents a simple flow profile to the solution.
Claim 13
Dependent Claim
197 words
A reusable biosensor device for measuring the concentration of a protein-catalyzed reagent in solution, which comprises: (a) an electrically conducting pin having one or more side surfaces, a transmitting surface, and a receiving surface; (b) a nonporous, electrically insulating housing which is impervious to the solution, covers only the side surfaces, and extends beyond the side surfaces so as to define a well that is adjacent the receiving surface; (c) an ionophore gel inside the well; and (d) a composite membrane located across the well and spaced from the pin, ultrasonically welded to the housing so that the composite membrane, the housing, and the receiving surface completely surround the ionophore gel and so that the solution must pass through the composite membrane to contact the ionophore gel; said composite membrane including a porous membrane co-extensive with the composite membrane and having a larger surface area than the cross-sectional area of the well as measured opposite the composite membrane and having an internal surface which defines micropores; a protein immobilized within the porous membrane; and a planar protecting membrane ultrasonically welded to the housing which covers the composite membrane and presents a simple flow profile to the solution.
Claim 14
Dependent Claim
15 words
The device of claim 10 wherein a layer of graphite ink coats the receiving surface.
Claim 15
Dependent Claim
28 words
The device of claim 10 wherein the composite membrane has a thickness and in that the thickness is in the range of about 20 to about 300 micrometers.
Claim 16
Dependent Claim
24 words
The device of claim 10 wherein the composite membrane is welded to the housing after the immobilized enzyme is attached to the porous membrane.
Claim 17
Dependent Claim
19 words
The device of claim 10 wherein the immobilized enzyme is dispersed throughout the porous membrane in a uniform distribution.
Claim 18
Dependent Claim
11 words
The device of claim 10 wherein the immobilized enzyme is urease.
Claim 19
Dependent Claim
12 words
The device of claim 10 wherein the immobilized enzyme is creatinine deiminase.
Claim 20
Independent Claim
134 words
A device for measuring the concentration of an enzyme-catalyzed reagent in a solution, which comprises: (a) an electrically conducting pin having a side and a receiving surface; (b) a layer of graphite ink which coats the receiving surface of the pin; (c) a thermoplastic polymer molded housing which covers only the sides of the pin and extends beyond the receiving surface so as to define a well adjacent the receiving surface; (d) a composite membrane disposed across the well including an enzyme membrane having functional groups, abutting the housing and extending over the well so that the solution must pass through the enzyme membrane to contact the receiving surface; an immobilized enzyme covalently attached to the functional groups; and a planar ultrafiltration protecting membrane covering the enzyme membrane and ultrasonically welded to the housing.
Claim 21
Independent Claim
134 words
A device for measuring the concentration of an enzyme-catalyzed reagent in a solution, which comprises: (a) an electrically conducting pin having a side and a receiving surface; (b) a layer of graphite ink which coats the receiving surface of the pin; (c) a thermoplastic polymer molded housing which covers only the sides of the pin and extends beyond the receiving surface so as to define a well adjacent the receiving surface; (d) a composite membrane disposed across the well including an enzyme membrane having functional groups, abutting the housing and extending over the well so that the solution must pass through the enzyme membrane to contact the receiving surface; an immobilized enzyme covalently attached to the functional groups; and a planar ultrafiltration protecting membrane covering the enzyme membrane and ultrasonically welded to the housing.
Claim 22
Dependent Claim
20 words
The device of claim 17 wherein an ionophore gel is surrounded by the pin, the housing, and the composite membrane.
References Cited (Backward Citations)
US3797274A
Cited
US3835014A
Cited
US4073713A
Cited
GB2003275A
Cited
US4240889A
Cited
US4276141A
Cited
US4321123A
Cited
US4376689A
Cited
US4388166A
Cited
US4486292A
Cited
US4415666A
Cited
US4454007A
Cited
US4579642A
Cited
US4549951A
Cited
US4808529A
Cited
US4894339A
Cited
US4909908A
Cited
GB2194843A
Cited
US4895806A
Cited
US4923586A
Cited
US4759828A
Cited
US4889612A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-07-04 | 1998-01-03 | 1998-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-07-04 | 2002-01-03 | 2002-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-07-04 | 2006-01-03 | 2006-07-05 | $7700.00 | Window Closed / Lapsed |