Patent US1954965A successfully refreshed from Google Patents.
Patent US3917453A successfully refreshed from Google Patents.
US3917453A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and device for determining the concentration of a substance in a fluid
Assignee: Polaroid Corp
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Filing: 1974-08-16
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Granted: 1975-11-04
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Expires: 1994-08-16
Abstract
Abstract A diagnostic test device comprising an absorbent medium and a reaction zone located between superposed sheets. The fluid containing the substance to be analyzed is placed on the absorbent medium. Compressive force is applied to the absorbent medium providing a predetermined quantity of fluid to the reaction zone where reagents are located to react with the substance to provide a colorimetric determination of the presence and/or concentration of the substance.
Inventors
- 👤 Terry W Milligan
- 👤 Richard F Wright
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:01
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/26; C12Q1/32; C12Q1/48; C12Q1/54; C12Q1/58; G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/52; G01N33/525; Y; Y10; Y10S; Y10S435/00; Y10S435/805
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
87 words
A METHOD FOR DETERMINING THE CONCENTRATION OF A SUBSTANCE IN A FLUID WHICH COMPRISES: DISPOSING SAID FLUID ONTO ABSORBENT FLUID RECEIVING MEANS DISPOSED INTERMEDIATE A FRIST AND SECOND SHEET IN SUPERPOSED RELATIONSHIP, SUBJECTING SAID ABSORBENT FLUID RECEIVING MEANS TO SUFFICIENT COMPRESSIVE FORCE TO DISCHARGE AT LEAST A PORTION OF SAID FLUID FROM SAID ABSORBENT FLUID RECEIVING MEANS INTO CONTACT WITH REAGENTS DISPOSED INTERMEDIATE SAID FRIST AND SECOND SHEETS, SAID REAGENTS ADAPTED TO REACT WITH SAID SUBSTANCE TO PROVIDE A VISUAL INDICATION OF THE CONCENTRATION OF SAID SUBSTANCE.
Claim 2
Independent Claim
87 words
A METHOD FOR DETERMINING THE CONCENTRATION OF A SUBSTANCE IN A FLUID WHICH COMPRISES: DISPOSING SAID FLUID ONTO ABSORBENT FLUID RECEIVING MEANS DISPOSED INTERMEDIATE A FRIST AND SECOND SHEET IN SUPERPOSED RELATIONSHIP, SUBJECTING SAID ABSORBENT FLUID RECEIVING MEANS TO SUFFICIENT COMPRESSIVE FORCE TO DISCHARGE AT LEAST A PORTION OF SAID FLUID FROM SAID ABSORBENT FLUID RECEIVING MEANS INTO CONTACT WITH REAGENTS DISPOSED INTERMEDIATE SAID FRIST AND SECOND SHEETS, SAID REAGENTS ADAPTED TO REACT WITH SAID SUBSTANCE TO PROVIDE A VISUAL INDICATION OF THE CONCENTRATION OF SAID SUBSTANCE.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein said absorbent fluid means comprises a sponge.
Claim 4
Dependent Claim
14 words
The method of claim 1 wherein said absorbent fluid means comprises a microporous filter.
Claim 5
Dependent Claim
24 words
The method of claim 1 which includes the step of removing undesirable components from said fluid prior to contacting said reagents with said fluid.
Claim 6
Dependent Claim
14 words
The method of claim 1 wherein said reagents comprise enzymes, coenzymes and colorimetric indicators.
Claim 7
Dependent Claim
29 words
The method of claim 5 wherein said enzymes and coenzymes are disposed on one of said sheets and said colorimetric indicator is disposed on the other of said sheets.
Claim 8
Dependent Claim
17 words
The method of claim 1 wherein at least one of said first and second sheets is transparent.
Claim 9
Dependent Claim
21 words
The method of claim 7 wherein one of said transparent sheets includes a colored scale indicating concentration standards for said substance.
Claim 10
Dependent Claim
10 words
The method of claim 1 wherein said fluid comprises blood.
Claim 11
Dependent Claim
20 words
The method of claim 9 wherein said reactants comprise hexokinase, glucose-6-phosphate dehydrogenase, and nicotinamide adenine dinucleotide phosphate and adenosine triphosphate.
References Cited (Backward Citations)
US2687041A
Cited
US3232710A
Cited
US2785057A
Cited
US3036894A
Cited
US3418083A
Cited
US3552928A
Cited
US3510263A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-03 | 1979-05-05 | 1979-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-03 | 1983-05-05 | 1983-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-03 | 1987-05-05 | 1987-11-04 | $7700.00 | Window Closed / Lapsed |