Patents Assigned to Quidel
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Patent number: 5763262Abstract: A device for assaying biological fluids for molecules contained therein comprising a container, material situated in the container for absorbing fluid and in communication with an antibody or antigen impregnated matrix, wherein the matrix is accessible to the exterior of the container through a funnel shaped aperture in the roof of the container. Further features include a chemical drying agent associated with the container for absorbing moisture, thereby preventing inactivation of the assay reagents, and a filter situated above the antibody or antigen impregnated matrix, and in communication with the matrix through the aperture in the roof of the container. The filter removes interfering substances present in the biological fluids and provides protein blocking agents to the matrix material for decreasing the background of the assay.Type: GrantFiled: April 3, 1992Date of Patent: June 9, 1998Assignee: Quidel CorporationInventors: Siu-Yin Wong, Fon-Chiu Mia Chen, Eugene Fan
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Patent number: 5741662Abstract: The present invention provides specific binding solid phase assay methods and kits for the detection of the presence or absence of a microorganism by directly staining the microorganism and specifically capturing the stained microorganism on a solid support. The methods find particular utility in the detection of Candida. The methods may simultaneously detect the presence or absence of multiple microorganisms.Type: GrantFiled: December 18, 1995Date of Patent: April 21, 1998Assignee: Quidel CorporationInventors: Randall D. Madsen, Lorraine S. Bautista, Jan W. Pawlak, Allan D. Pronovost
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Patent number: 5686315Abstract: A "one step" device for the detection of analytein clinical assays is disclosed. A visible label comprising a visible moiety and a ligand that binds to or competes with analyte is contained in a fluid conducting membrane or prefilter; and the analyte and associated ligand are conducted by the flow of sample into a detection zone. The detection zone contains a capture reagent that binds to label or to analyte bound to label.Type: GrantFiled: January 21, 1994Date of Patent: November 11, 1997Assignee: Quidel CorporationInventors: Allan D. Pronovost, Cathy A. Bacquet, Jan W. Pawlak, Theodore T. Sand
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Patent number: 5541069Abstract: An assay for determining the presence of a threshold concentration of an analyte in a sample comprises first reacting the sample with an amount of anti-analyte selected to reduce the free analyte to a marginally detectable concentration. The sample is then contacted with anti-analyte immobilized on a test region or indicator zone on a solid phase, whereby the residual free analyte may be bound. The binding of free analyte to immobilized anti-analyte is detected by a variety of techniques to indicate the presence of the threshold concentration. By employing limited amounts of anti-analyte on the solid phase, the change between maximum binding of label and no binding of label will be responsive to very small changes in the analyte concentration originally present in the sample.Type: GrantFiled: February 28, 1992Date of Patent: July 30, 1996Assignee: Quidel CorporationInventors: Richard B. Mortensen, Henry K. Tom
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Patent number: 5536646Abstract: Polysaccharide antigens characteristic of Group A or B Streptococci are extracted for use in immunodiagnostic assays by a simplified method. The method involves the use of two dried reagents, sodium nitrite and Tris base, and a liquid reagent, acetic acid.Type: GrantFiled: February 24, 1994Date of Patent: July 16, 1996Assignee: Quidel CorporationInventors: Theodore T. Sand, James A. Gordon, Allan D. Pronovost
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Patent number: 5521102Abstract: An improved one-step immunochromatographic assay which involves the binding of a predetermined amount of analyte to an antibody, enabling the control of the assay sensitivity, is disclosed. The system is especially useful as a controlled sensitivity fecal occult blood assay. Antibodies to a desired analyte, present at a predetermined concentration, are deposited on the sample pad of the reaction unit. The antibody binds analyte present in the sample, up to a threshold amount. Analyte which is present in the sample at a level above the threshold amount proceeds unbound through the sample pad and onto a membrane, where it reacts with an antibody-coated latex and a second, immobilized antibody to generate a positive signal.Type: GrantFiled: August 8, 1994Date of Patent: May 28, 1996Assignee: Quidel CorporationInventors: Hans R. Boehringer, Jan L. Sabran, Ya-Chen Hsu, Bentley Tam
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Patent number: 5434057Abstract: The present invention provides devices, methods and kits for assessing fertility potential of semen samples. Semen samples may be assayed by the present invention to identify those samples having more than 20.times.10.sup.6 motile sperm per milliliter, a concentration associated with fertile samples.Type: GrantFiled: February 2, 1994Date of Patent: July 18, 1995Assignee: Quidel CorporationInventor: Randel Dorian
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Patent number: 5424193Abstract: The present invention relates generally to test articles and assays for the detection of analytes in biological fluid samples. More particularly, the present invention relates to test articles an assays which employ dyed microorganisms as visual labels to detect suspected analytes.Type: GrantFiled: February 25, 1993Date of Patent: June 13, 1995Assignee: Quidel CorporationInventors: Allan D. Pronovost, Gerald L. Rowley
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Patent number: 5415994Abstract: The present invention provides devices, methods, and kits for treatment and detection of analytes requiring pretreatment in samples. One-step treatment and detection is possible utilizing the devices and methods of the present invention.Type: GrantFiled: August 2, 1993Date of Patent: May 16, 1995Assignee: Quidel CorporationInventors: Michael R. Imrich, John K. Zeis, Steven P. Miller, Allan D. Pronovost
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Patent number: 5225328Abstract: Methods and compositions for membrane flow-through assays using substrate and enzyme conjugate is described. A preferred method of the present invention comprises providing E. coli alkaline phosphatase (ECAP) conjugate, with additional color enhancement provided by combining lithium salt with the substrate, calcium and/or magnesium salts with the conjugate, and polyalcohol polymers with the conjugate. Color development is further enhanced by spotting tetrazolium dyes, such as the Nitro Blue tetrazolium series, onto the membrane.Type: GrantFiled: May 30, 1991Date of Patent: July 6, 1993Assignee: Quidel CorporationInventor: Chin-Hai Chang
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Patent number: 5221616Abstract: Selected polyhydroxyl compounds, comprising monosaccharides, disaccharides and oligosaccharides, as well as certain of their derivatives, are effective in preventing the spontaneous activation of complement in vitro. The effect is enhanced in the presence of an anticoagulant together with a divalent cation chelator. Addition of these compounds makes it possible to store clinical samples at conventional temperatures from -20.degree. to +22.degree. C. for extended periods prior to performing complement protein assays. Effective compounds are selected through a screening protocol which comprises the use of immunoassays for complement fragments together with an algorithm for computing effectiveness. Polyhydroxyl compounds extend similar protection from activation to coagulation proteins.Type: GrantFiled: July 15, 1988Date of Patent: June 22, 1993Assignee: Quidel CorporationInventors: William P. Kolb, Linda M. Kolb, John D. Tamerius
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Patent number: 5118428Abstract: Red Blood Cells (RBC's) are removed from whole blood samples by contacting the whole blood sample with a solution containing an acid selected from the group consisting of acetic acid, citric acid, ascorbic acid, lactic acid, maleic acid, malic acid, and malonic acid. The agglutinated RBC's are then removed from the resultant suspension by procedures of filtration, centrifugation or decantation, leaving an essentially RBC-free serum or plasma sample.Type: GrantFiled: November 13, 1990Date of Patent: June 2, 1992Assignee: QuidelInventors: Theodore T. Sand, Barbara McLaughlin, William P. Kolb
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Patent number: 5118630Abstract: A natural birth control method comprises observance of the first day of menses followed by measurement of urinary progesterone metabolite levels beginning a predetermined number of days after the first day of menses. Urinary progesterone metabolite measurement is performed on days of planned sexual activity until the concentration level exceeds a threshold value indicative of ovulation occurring more than 24 hours previously. Once such a threshold value is observed, the woman may discontinue testing and can consider herself unable to conceive until after the beginning of the subsequent menstrual cycle.Type: GrantFiled: November 4, 1988Date of Patent: June 2, 1992Assignee: Quidel CorporationInventor: Thomas A. Glaze
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Patent number: 5079170Abstract: A sample applicator for use in performing immunoassays comprises a tube defining an internal lumen and having a filter matrix at one end thereof. Sample is drawn into the applicator tube, either using a vacuum bulb or an automated assay device. The sample is filtered as it enters the tube, and is again filtered as it discharged from the tube in the opposite flow direction. By removing particulates from the liquid sample, assay performance can be greatly improved. The applicator may also comprise a reagent dispersed within a permeable matrix, which is useful for introducing reagent to a sample or other liquid assay component. As a liquid assay component is drawn into the applicator tube, the reagent is reconstituted by and mixed with the liquid, thereby reducing the number of steps required for the assay.Type: GrantFiled: October 25, 1990Date of Patent: January 7, 1992Assignee: Quidel CorporationInventors: Daniel B. Rosman, Douglas D. Rundle, Gary A. Ascani, Richard B. Mortensen, Henry Tom
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Patent number: 4943522Abstract: A method and apparatus for conducting specific binding pair assays, such as immunoassays, is described. A porous membrane capable of non-bibulous lateral flow is used as assay substrate; a member of the binding pair is affixed in an indicator zone defined in the substrate. The sample is applied at a position distant from the indicator zone and permitted to flow laterally through the zone; any analyte in the sample is complexed by the affixed specific binding member, and detected. A novel method of detection employs entrapment of observable particle in the complex. Blood is a particularly preferred sample as the red blood cells can be used as the observable particles for detection of the complex.Type: GrantFiled: August 10, 1988Date of Patent: July 24, 1990Assignee: QuidelInventors: Robert W. Eisinger, Mohammed H. Khalil, David H. Katz, Robert B. Sargeant
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Patent number: 4496654Abstract: Human chorionic gonadotropin (HCG) is detected by enzyme immunoassay by bonding biotinylated antibody to an avidin coupled paper disc, reacting the antibody on the disc with the solution suspected of containing HCG, and determining the amount of HCG on the disc by enzymatic assay detection techniques.Type: GrantFiled: April 8, 1983Date of Patent: January 29, 1985Assignee: QuidelInventors: David H. Katz, Steven W. Cooper, Theodore T. Lee, Shung-Ho Chang
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Patent number: 4458020Abstract: A system for conducting an immunoassay in a single chamber, by concentrating antibodies for antigenic components on microbeads treated for binding immunological components, physically separating the fluid from which the immunological active component is separated, and determining the amount of immunological component collected on the beads, comprising a multiple-chamber dispensing cylinder.Type: GrantFiled: November 15, 1982Date of Patent: July 3, 1984Assignee: QuidelInventors: Joseph W. Bohn, Peter A. Cohen, Bruce L. Zuraw
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Patent number: 4424279Abstract: A method and apparatus for conducting an immunoassay. The apparatus features a cylindrical tube having one open end into which a plunger filter assembly is slidably fitted. The filter assembly is composed of a plunger filter cylinder open at both ends, a seal fixed to the proximal end of the plunger filter cylinder and a dome-shaped filter inside of and closing the proximal end of the plunger filter cylinder, and beads sensitized with an immunologically reactive material, such as an antibody.Type: GrantFiled: August 12, 1982Date of Patent: January 3, 1984Assignee: QuidelInventors: Joseph W. Bohn, Peter A. Cohen, Bruce L. Zuraw