US5212060A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dry test strip comprising a dextran barrier for excluding erythrocytes
Assignee: Genesis Labs Inc
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Filing: 1990-04-27
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Granted: 1993-05-18
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Expires: 2010-04-27
Abstract
Abstract A dry test strip for the detection of an analyte in a test fluid is disclosed. The test strip comprises a porous detection zone containing a reactant system that can generate a signal in the presence of an analyte. The detection zone further comprises dextran as a barrier to prevent penetration of RBC's into the detection zone.
Inventors
- 👤 Catherine B. Maddox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:38
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/52; G01N33/521; B; B01; B01L; B01L3/00; B01L3/50; B01L3/502; B01L3/5023; B01L2300/00; B01L2300/06; B01L2300/0681; B01L2300/08; B01L2300/0809; B01L2300/0825; B01L2400/00; B01L2400/04; B01L2400/0403; B01L2400/0406; Y; Y10; Y10S; Y10S435/00; Y10S435/962; Y10S435/97; Y10S436/00; Y10S436/807; Y10S436/808; Y10S436/825; Y10T; Y10T436/00; Y10T436/25; Y10T436/25125
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
136 words
A dry test strip for detection of an analyte in a test fluid comprising: (a) a porous detection zone having a test fluid application site physically separate from a visualization site containing a signal generating system that produces a signal in the presence of the analyte, wherein the detection zone pores are about 0.04 to 1 micron; and (b) dextran, having a molecular weight of about 10,000 to 50,000 dispersed in the detection zone at a concentration effective to prevent penetration of red blood cells through the detection zone to the visualization site; wherein any red blood cells present in the test fluid interact with the dextran adjacent the test fluid application site to prevent their penetration through the detection zone to the visualization site thereby essentially eliminating red blood cell interference with the signal generation.
Claim 2
Dependent Claim
136 words
A dry test strip for detection of an analyte in a test fluid comprising: (a) a porous detection zone having a test fluid application site physically separate from a visualization site containing a signal generating system that produces a signal in the presence of the analyte, wherein the detection zone pores are about 0.04 to 1 micron; and (b) dextran, having a molecular weight of about 10,000 to 50,000 dispersed in the detection zone at a concentration effective to prevent penetration of red blood cells through the detection zone to the visualization site; wherein any red blood cells present in the test fluid interact with the dextran adjacent the test fluid application site to prevent their penetration through the detection zone to the visualization site thereby essentially eliminating red blood cell interference with the signal generation.
Claim 3
Dependent Claim
18 words
The dry test strip of claim 1 wherein the dextran comprises a polymer of D-glucose having αD-(1→6) linkages.
Claim 4
Dependent Claim
21 words
The dry test strip of claim 1 wherein the signal generating system contained within the detection zone comprises a chemical assay.
Claim 5
Dependent Claim
16 words
The dry test strip of claim 3 wherein the chemical assay comprises a glucose assay reagent.
Claim 6
Dependent Claim
16 words
The dry test strip of claim 3 wherein the chemical assay comprises a cholesterol assay reagent.
Claim 7
Dependent Claim
19 words
The dry test strip of claim 1 wherein the signal generating system in the detection zone comprises an immunoassay.
Claim 8
Dependent Claim
59 words
The dry test strip of claim 6 wherein the detection zone comprises a first labeled reagent zone containing a labeled antibody or fragment thereof specific for the analyte, a second trapping zone comprising immobilized antigen which specifically binds unbound labeled antibody or fragment thereof, and a third signal generation zone containing means to detect the presence of the label.
Claim 9
Dependent Claim
18 words
The dry test strip of claim 1 wherein the detection zone is adhered to a polymeric carrier strip.
Claim 10
Dependent Claim
102 words
A dry test strip for detection of an analyte, in a test fluid containing red blood cells which comprises a carrier strip having a porous detection zone having pores of about 0.04 to 1 micron and containing a signal generating system that produces a signal in the presence of the analyte, said detection zone having a discrete barrier layer on the surface of the detection zone comprising a sufficient amount of dextran having a molecular weight of about 10,000 to 50,000 to prevent the penetration through the porous detection zone and interference with the signal generation system by the red blood cells.
Claim 11
Dependent Claim
102 words
A dry test strip for detection of an analyte, in a test fluid containing red blood cells which comprises a carrier strip having a porous detection zone having pores of about 0.04 to 1 micron and containing a signal generating system that produces a signal in the presence of the analyte, said detection zone having a discrete barrier layer on the surface of the detection zone comprising a sufficient amount of dextran having a molecular weight of about 10,000 to 50,000 to prevent the penetration through the porous detection zone and interference with the signal generation system by the red blood cells.
Claim 12
Dependent Claim
18 words
The dry test strip of claim 9 wherein the dextran comprises a polymer of D-glucose having αD-(1→6) linkages.
Claim 13
Dependent Claim
21 words
The dry test strip of claim 9 wherein the signal generating system contained in the detection zone comprises a chemical assay.
Claim 14
Dependent Claim
19 words
The dry test strip of claim 9 wherein the signal generating system in the detection zone comprises an immunoassay.
Claim 15
Dependent Claim
59 words
The dry test strip of claim 12 wherein the detection zone comprises a first labeled reagent zone containing a labeled antibody or fragment thereof specific for the analyte, a second trapping zone comprising immobilized antigen which specifically binds unbound labeled antibody or fragment thereof, and a third single generation zone containing means to detect the presence of the label.
Claim 16
Independent Claim
150 words
A method for detecting an analyte in a test fluid which method comprises: (a) applying the test fluid to a dry test strip comprising a porous detection zone having pores of about 0.04 to 1 micron and a test fluid application site physically separate from a visualization site containing: (i) a signal generating system that produces a signal in the presence of the analyte; and (ii) dextran having a molecular weight of about 10,000 to 50,000, dispersed through the detection zone at a concentration effective to prevent penetration of any red blood cells present in the fluid through the detection zone; and (b) detecting the concentration of the analyte; wherein any red blood cells present in the test fluid interact with the dextran adjacent the application site to prevent their penetration through the detection zone to the visualization site thereby essentially eliminating red blood cell interference with the signal generation.
Claim 17
Independent Claim
150 words
A method for detecting an analyte in a test fluid which method comprises: (a) applying the test fluid to a dry test strip comprising a porous detection zone having pores of about 0.04 to 1 micron and a test fluid application site physically separate from a visualization site containing: (i) a signal generating system that produces a signal in the presence of the analyte; and (ii) dextran having a molecular weight of about 10,000 to 50,000, dispersed through the detection zone at a concentration effective to prevent penetration of any red blood cells present in the fluid through the detection zone; and (b) detecting the concentration of the analyte; wherein any red blood cells present in the test fluid interact with the dextran adjacent the application site to prevent their penetration through the detection zone to the visualization site thereby essentially eliminating red blood cell interference with the signal generation.
Claim 18
Dependent Claim
16 words
The method of claim 14 wherein the dextran comprises a polymer a D-glucose having αD-(1→6) linkages.
Claim 19
Dependent Claim
19 words
The method of claim 14 wherein the signal generating system contained within the detection zone comprises a chemical assay.
Claim 20
Dependent Claim
17 words
The method of claim 14 wherein the signal generating system in the detection zone comprises an immunoassay.
Claim 21
Dependent Claim
58 words
The method of claim 17 wherein the detection zone comprises a first labeled reagent zone containing a labeled antibody or fragment thereof specific for the analyte, a second trapping zone comprising immobilized antigen which specifically binds unbound labeled antibody or fragment thereof, and a third single generation zone containing means to detect the presence of the antibody label.
Claim 22
Dependent Claim
25 words
The method of claim 14 wherein the test fluid is selected from the group consisting of serum, plasma, urine, cerebral spinal fluid, ascites, and saliva.
Claim 23
Dependent Claim
29 words
The method of claim 14 wherein the test fluid comprises whole blood, a red blood cell containing fraction thereof or a red blood cellular suspension in a compatible diluent.
Claim 24
Dependent Claim
16 words
The method of claim 14 wherein the detection zone is adhered to a polymeric carrier strip.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1996-05-17 | 1996-11-16 | 1997-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-05-17 | 2000-11-16 | 2001-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-05-17 | 2004-11-16 | 2005-05-18 | $7700.00 | Window Closed / Lapsed |