Patents by Inventor Paul J. Lawrence
Paul J. Lawrence has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 5268146Abstract: A dry test panel for the testing of samples such as undiluted bodily fluid specimens is disclosed. The panel contains all reagents and components necessary to achieve a visible indication of the presence or absence of a suspect analyte in the sample, and preferred embodiments contain positive and negative controls as well. The device contains an internal chamber into which the specimen is introduced, and which contains all materials necessary for the reactions which produce a color change which is visible on the outer surface of the device. The materials are positioned in the chamber in such a manner that they are activated only when the chamber is filled with the specimen, and the color indicator is concentrated in a thin lamina immediately adjacent to a light-transmitting wall of the device so that a detectable color change occurs in a short period of time to produce a sensitive and yet fast test.Type: GrantFiled: March 25, 1992Date of Patent: December 7, 1993Assignee: Litmus Concepts, Inc.Inventors: Paul J. Lawrence, Marian B. Buccafurni, Leah P. Lawrence
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Patent number: 5068197Abstract: An improved method for detecting peroxidatively active materials in a sample is provided, the method incorporating antimalarial drugs such as quinine, quinidine, chloroquine, primaquine, and quinacrine as modulating compounds. In a preferred embodiment, the method is a fecal occult blood test (FOBT), in which a fecal specimen is contacted with a chromogen and a hydroperoxide in the presence of a selected quinoline derivative. The method enables careful modulation of test sensitivity and specificity, and further provides an FOBT in which interference from dietary meat ingestion is substantially eliminated.Type: GrantFiled: May 17, 1990Date of Patent: November 26, 1991Assignee: Litmus Concepts, Inc.Inventor: Paul J. Lawrence
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Patent number: 5053342Abstract: An improved method for detecting peroxidatively active materials in a sample is provided, the method incorporating antimalarial drugs such as quinine, quinidine, chloroquine, primaquine, and quinacrine as modulating compounds. In a preferred embodiment, the method is a fecal occult blood test (FOBT), in which a fecal specimen is contacted with a chromogen and a hydroperoxide in the presence of a selected quinoline derivative. The method enables careful modulation of test sensitivity and specificity, and further provides an FOBT in which interference from dietary meat ingestion is substantially eliminated.Type: GrantFiled: May 7, 1990Date of Patent: October 1, 1991Assignee: Litmus Concepts, Inc.Inventor: Paul J. Lawrence
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Patent number: 4971914Abstract: Fecal occult blood tests of enhanced sensitivity, specificity, and readability are provided by employing (1) a developer or complete reagent solution that uses as a solvent system a solvent comprising at least about 50% by volume of a solvent for iron protoporphyrins such as dimethyl sulfoxide and/or (2) a multi-chromagen comprised of a mixture of guaiac and ABTS. Test results may be further improved by incorporating hemoprotein solubilizing agents, plant peroxidase inhibitors, iron/copper chelating agents, accelerators and buffers in the developer/reagent.Type: GrantFiled: March 28, 1988Date of Patent: November 20, 1990Assignee: Litmus Concepts, Inc.Inventor: Paul J. Lawrence
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Patent number: 4942132Abstract: Fecal occult blood tests of enhanced sensitivity, specificity, and readability are provided by employing (1) a developer or complete reagent solution that uses as a solvent system a solvent comprising at least about 50% by volume of a solvent for iron protoporphyrins such as dimethyl sulfoxide and/or (2) a multi-chromagen comprised of a mixture of guaiac and ABTS. Test results may be further improved by incorporating hemoprotein solubilizing agents, plant peroxidase inhibitors, iron/copper chelating agents, accelerators and buffers in the developer/reagent.Type: GrantFiled: March 28, 1988Date of Patent: July 17, 1990Assignee: Litmus Concepts, Inc.Inventor: Paul J. Lawrence
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Patent number: 4939097Abstract: An improved method for detecting peroxidatively active materials in a sample is provided, the method incorporating antimalarial drugs such as quinine, quinidine, chloroquine, primaquine, and quinacrine as modulating compounds. In a preferred embodiment, the method is a fecal occult blood test (FOBT), in which a fecal specimen is contacted with a chromogen and a hydroperoxide in the presence of a selected quinoline derivative. The method enables careful modulation of test sensitivity and specificity, and further provides an FOBT in which interference from dietary meat ingestion is substantially eliminated.Type: GrantFiled: December 24, 1987Date of Patent: July 3, 1990Assignee: Litmus Concepts, Inc.Inventor: Paul J. Lawrence
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Patent number: 4937197Abstract: Fecal occult blood tests of enhanced sensitivity, specificity, and readability are provided by employing (1) a developer or complete reagent solution that uses as a solvent system a solvent comprising at least about 50% by volume of a solvent for iron protoporphyrins such as dimethyl sulfoxide and/or (2) a multi-chromagen comprised of a mixture of guaiac and ABTS. Test results may be further improved by incorporating hemoprotein solubilizing agents, plant peroxidase inhibitors, iron/copper chelating agents, accelerators and buffers in the developer/reagent.Type: GrantFiled: February 11, 1988Date of Patent: June 26, 1990Assignee: Litmus Concepts, Inc.Inventor: Paul J. Lawrence
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Patent number: 4820646Abstract: Fecal occult blood tests of enhanced sensitivity, specificity, and readability are provided by employing (1) a developer or complete reagent solution that uses as a solvent system a solvent comprising at least about 50% by volume of a solvent for iron protoporphyrins such as dimethyl sulfoxide and/or (2) a multi-chromogen comprised of a mixture of guaiac and ABTS. Test results may be further improved by incorporating hemoprotein solubilizing agents, plant peroxidase inhibitors, iron/copper chelating agents, accelerators and buffers in the developer/reagent.Type: GrantFiled: March 28, 1988Date of Patent: April 11, 1989Assignee: Litmus Concepts, Inc.Inventor: Paul J. Lawrence
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Patent number: 4818702Abstract: Fecal occult blood tests of enhanced sensitivity, specificity, and readability are provided by employing (1) a developer or complete reagent solution that uses as a solvent system a solvent comprising at least about 50% by volume of a solvent for iron protoporphyrins such as dimethyl sulfoxide and/or (2) a multi-chromogen comprised of a mixture of guaiac and ABTS. Test results may be further improved by incorporating hemoprotein solubilizing agents, plant peroxidase inhibitors, iron/copper chelating agents, accelerators and buffers in the developer/reagent.Type: GrantFiled: March 31, 1988Date of Patent: April 4, 1989Assignee: Litmus Concepts, Inc.Inventor: Paul J. Lawrence
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Patent number: 4777143Abstract: A method for detecting the presence of carboxylic acids in a specimen is provided. A specimen is contacted with a developing system containing a metal salt reactive with carboxylic acids present in the specimen to form metal-carboxylic acid complexes. Any such complexes are colorimetrically detected by their activity in catalyzing oxidation of a chromogen such as guaiac. The method is useful in detecting intestinal helminth infestation.Type: GrantFiled: December 12, 1986Date of Patent: October 11, 1988Assignee: Litmus Concepts Inc.Inventors: Neil H. Price, Paul J. Lawrence
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Patent number: 4615982Abstract: Fecal occult blood tests of enhanced sensitivity and specificity are provided by employing (1) a developer composition comprising a solution of a hydroperoxide in a solvent comprising at least about 50% by volume of a solvent for iron protoporphyrins such as dimethyl sulfoxide and/or (2) a solid test matrix comprising a solid support impregnated with a leuco dye and a hemoprotein solubilizing agent. Test results may be further improved by incorporating plant peroxidase inhibitors, iron/copper chelating agents and buffers in the developer and/or test matrix.Type: GrantFiled: December 11, 1984Date of Patent: October 7, 1986Inventor: Paul J. Lawrence
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Patent number: 4486536Abstract: A method and novel absorbent substrate for determining the presence of occult blood in gastric fluid. The substrate is acid treated and contains guaiac. The method includes the addition of the gastric fluid to the acid treated guaiac substrate which is developed with a buffered developing solution. Preferably the substrate is an acid treated sheet of absorbent paper and the developing solution is an aqueous buffered solution of hydrogen peroxide.Type: GrantFiled: August 19, 1982Date of Patent: December 4, 1984Assignee: Smithkline Diagnostics, Inc.Inventors: Josefina T. Baker, Paul J. Lawrence, Charles W. Townsley
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Patent number: 4382064Abstract: Specimen test slides for occult blood having a receiving sheet between a front panel and a rear panel with openings in the front and rear panels and pivotal covers coated with 2,6-di-tert-butyl-p-cresol to cover said openings.Type: GrantFiled: February 11, 1982Date of Patent: May 3, 1983Assignee: SmithKline Instruments, Inc.Inventors: Michael B. Detweiler, Paul J. Lawrence, Charles W. Townsley
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Patent number: 4365970Abstract: An improved specimen test slide having a front panel and a rear panel. The front panel has one or more openings. Sheet means carrying a test reagent underlie each of these openings for reception of a specimen. A hinged cover overlies the openings. The rear panel has flap means opposite said openings which is pivotable to expose the underside of the sheet to permit application of a developing solution. The underside of the sheet which faces the rear panel also has a control area positioned on a portion thereof at some distance from the portions of the sheet underlying the openings of the front panel. The control area contains positive and negative monitors.Type: GrantFiled: May 1, 1981Date of Patent: December 28, 1982Assignee: SmithKline Instruments, Inc.Inventors: Paul J. Lawrence, Charles W. Townsley
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Patent number: 4329317Abstract: Specimen test slides for occult blood having a receiving sheet between a front panel and a rear panel with openings in the front and rear panels and pivotal covers coated with 2,6-di-tert-butyl-p-cresol to cover said openings.Type: GrantFiled: January 29, 1981Date of Patent: May 11, 1982Assignee: Smithkline Instruments, Inc.Inventors: Michael B. Detweiler, Paul J. Lawrence, Charles W. Townsley