Patents by Inventor Douglas Christensen

Douglas Christensen 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).

  • Publication number: 20020160534
    Abstract: Methods and apparatus for evanescent light fluoroimmunoassays are disclosed. The apparatus employs a planar waveguide and optionally has multi-well features and improved evanescent field intensity. The preferred biosensor and assay method have the capture molecules immobilized to the waveguide surface by site-specific coupling chemistry. Additionally, the coatings used to immobilize the capture molecules provide reduced non-specific protein adsorption.
    Type: Application
    Filed: October 5, 2001
    Publication date: October 31, 2002
    Inventors: James N. Herron, Douglas A. Christensen, Karin D. Caldwell, Vera Janatova, Shao-Chie Huang, Hsu-Kun Wang
  • Publication number: 20020094147
    Abstract: Improvements in a biosensor are disclosed. A biosensor includes a waveguide, at least a portion of which is substantially planar. One or more reservoirs may be formed adjacent to a chemistry-bearing surface of the waveguide. The biosensor may include a gasket to form a seal between the waveguide and side walls of the reservoir. A sample solution may be introduced into the reservoir or otherwise onto the surface of a waveguide through an input port. Waveguides of varying composition (e.g., plastic, quartz, glass, or other suitable waveguide materials) may be used in the biosensor. Also disclosed is a sled-shaped waveguide, which includes a planar portion and a lens at an end thereof and angled relative thereto for coupling light into the waveguide.
    Type: Application
    Filed: March 11, 2002
    Publication date: July 18, 2002
    Inventors: James N. Herron, Douglas A. Christensen, Victor A. Pollak, Richard D. McEachern, Eric M. Simon
  • Publication number: 20020034457
    Abstract: A composite waveguide for evanescent sensing in fluorescent binding assays comprising a substrate layer having one or more thin film waveguide channels deposited thereon. Binding molecules having the property of binding with specificity to an analyte are immobilized on the surface of the thin film channels. In preferred embodiments, the composite waveguide includes integral light input coupling means adapted to the thin film channels. Light coupling means may include a grating etched into the substrate prior to deposition of the thin film, or a waveguide coupler affixed to the upper surface of the thin film. The waveguide coupler has an input waveguide of high refractive index which receives the laser light through one end, propagating it by total internal reflection. Propagated light is coupled evanescently into the thin film across a spacer layer of precise thickness with a lower index of refraction than the input waveguide or the thin-film waveguide.
    Type: Application
    Filed: October 10, 2001
    Publication date: March 21, 2002
    Inventors: W. Monty Reichert, James N. Herron, Douglas A. Christensen, Hsu-Kun Wang
  • Patent number: 6356676
    Abstract: Improvements in a biosensor of the type having reservoirs or wells for analyzing a biological liquid are disclosed. A biosensor includes a waveguide placed between a plurality of members such as plates at least one of the members being formed to define the walls of the reservoirs where the liquid is biologically analyzed. The walls of the reservoirs are made of an inert, opaque material such as a metal. Although the biosensor may include a gasket, the gasket is associated with the members and waveguide in such a way (e.g., by recessing the gasket into a channel formed into a metal plate) so that the gasket does not form any significant portion of the reservoir wall. Waveguides of varying composition (e.g., plastic, quartz or glass) may be associated with the members to form the biosensor. The metal plate of the biosensor has input and output ports for infusing, draining, or oscillating the liquid to be analyzed in the reaction reservoir.
    Type: Grant
    Filed: June 30, 2000
    Date of Patent: March 12, 2002
    Assignee: University of Utah Research Foundation
    Inventors: James N. Herron, Douglas A. Christensen, Victor A. Pollak, Richard D. McEachern, Eric M. Simon
  • Patent number: 6350413
    Abstract: A step-gradient composite waveguide for evanescent sensing in fluorescent binding assays comprises a thick substrate layer having one or more thin film waveguide channels deposited thereon. In one embodiment, the substrate is silicon dioxide and the thin film is silicon oxynitride. Specific binding molecules having the property of binding with specificity to an analyte are immobilized on the surface of the thin film channels. In preferred embodiments, the composite waveguide further includes light input coupling means integrally adapted to the thin film channels. Such light coupling means can be a grating etched into the substrate prior to deposition of the thin film, or a waveguide coupler affixed to the upper surface of the thin film. The waveguide coupler has a thick input waveguide of high refractive index which receives the laser light through one end and propagates it by total internal reflection.
    Type: Grant
    Filed: October 5, 1999
    Date of Patent: February 26, 2002
    Assignee: University of Utah Research Foundation
    Inventors: W. Monty Reichert, James N. Herron, Douglas A. Christensen, Hsu-Kun Wang
  • Patent number: 6340598
    Abstract: Methods and apparatus for evanescent light fluoroimmunoassays are disclosed. The apparatus employs a planar waveguide and optionally has multi-well features and improved evanescent field intensity. The preferred biosensor and assay method have the capture molecules immobilized to the waveguide surface by site-specific coupling chemistry. Additionally, the coatings used to immobilize the capture molecules provide reduced non-specific protein adsorption.
    Type: Grant
    Filed: December 8, 1998
    Date of Patent: January 22, 2002
    Assignee: University of Utah Research Foundation
    Inventors: James N. Herron, Douglas A. Christensen, Karin D. Caldwell, Vera Janatová, Shao-Chie Huang, Hsu-Kun Wang
  • Patent number: 6316274
    Abstract: Methods and apparatus for evanescent light fluoroimmunoassays are disclosed. The apparatus employs a planar waveguide with an integral semi-cylindrical lens, and has multi-analyte features and calibration features, along with improved evanescent field intensity. A preferred embodiment of the biosensor and assay method have patches of capture molecules each specific for a different analyte disposed adjacent within a single reservoir. The capture molecules are immobilized to the patches on the waveguide surface by site-specific coupling of thiol groups on the capture molecules to photo-affinity crosslinkers which in turn are coupled to the waveguide surface or to a non-specific-binding-resistant coating on the surface. The patches of different antibodies are produced by selectively irradiating a portion of the waveguide surface during the process of coupling the photo-affinity crosslinkers the selective irradiation involving a mask, a laser light source, or the like.
    Type: Grant
    Filed: March 1, 2000
    Date of Patent: November 13, 2001
    Assignee: University of Utah Research Foundation
    Inventors: James N. Herron, Douglas A. Christensen, Hsu-Kun Wang, Karin Caldwell, Vera Janatová, Shao-Chie Huang
  • Publication number: 20010030741
    Abstract: A method and apparatus of diagnosing a cardiac disease state in as little as two minutes involving the utilization of an evanescent wave assay system in conjunction with a data acquisition and analysis procedure that monitors the precision of assay results in real time (i.e., while data is being acquired). The method includes diagnosing a disease state using a diagnostic procedure (e.g., an immunoassay) wherein the testing device informs the person conducting the test of the results of the test as soon as reliable test data is obtained (generally, <5% variation in the reaction rate of the assay). After which point, the diagnostic procedure may be terminated.
    Type: Application
    Filed: June 8, 2001
    Publication date: October 18, 2001
    Inventors: James N. Herron, Douglas A. Christensen, Jacob D. Durtschi
  • Patent number: 6287871
    Abstract: The present invention relates to a system (80) for determining analyte concentration. The system (80) includes an optical detection system (92) that detects fluorescence from fluorescent binding assays in a biosensor (88). A processing system (96) may be used to determine analyte concentration from the fluorescence detected by the optical detection system (92). The optical detection system (92) may include photodetectors with or without in series lenses. Alternatively, a CCD camera (146) may be used.
    Type: Grant
    Filed: September 18, 1998
    Date of Patent: September 11, 2001
    Assignee: University of Utah Research Foundation
    Inventors: James N. Herron, Douglas A. Christensen
  • Publication number: 20010019405
    Abstract: A method and apparatus of diagnosing a cardiac disease state in as little as two minutes involving the utilization of an evanescent wave assay system in conjunction with a data acquisition and analysis procedure that monitors the precision of assay results in real time (i.e., while data is being acquired). The method includes diagnosing a disease state using a diagnostic procedure (e.g., an immunoassay) wherein the testing device informs the person conducting the test of the results of the test as soon as reliable test data is obtained (generally, <5% variation in the reaction rate of the assay). After which point, the diagnostic procedure may be terminated.
    Type: Application
    Filed: April 20, 2001
    Publication date: September 6, 2001
    Inventors: James N. Herron, Douglas A. Christensen, Jacob D. Durtschi
  • Patent number: 6242267
    Abstract: An apparatus and method for rapidly analyzing samples for analytes of interest by an homogeneous immunofluorescence assay. The apparatus includes a sample test cartridge having a high control sample section, a low control sample section, and at least one test sample section. Each of these sections contain at least one pre-loaded reagent housed in a well within the cartridge wherein the low control sample section contains a known low amount of an analyte of interest and the high control sample section contains a known high amount of an analyte of interest. The cartridge includes a biosensor comprising a planar waveguide having first and second parallel plane surfaces and an edge extending between them, the edge having a receiving region for receiving a light beam.
    Type: Grant
    Filed: September 18, 1998
    Date of Patent: June 5, 2001
    Assignee: University of Utah Research Foundation
    Inventors: James N. Herron, Douglas A. Christensen, Scott D. Miles
  • Patent number: 6222619
    Abstract: A method and apparatus of diagnosing a cardiac disease state in as little as two minutes involving the utilization of an evanescent wave assay system in conjunction with a data acquisition and analysis procedure that monitors the precision of assay results in real time (i.e., while data is being acquired). The method includes diagnosing a disease state using a diagnostic procedure (e.g., an immunoassay) wherein the testing device informs the person conducting the test of the results of the test as soon as reliable test data is obtained (generally, <5% variation in the reaction rate of the assay). After which point, the diagnostic procedure may be terminated.
    Type: Grant
    Filed: September 18, 1997
    Date of Patent: April 24, 2001
    Assignee: University of Utah Research Foundation
    Inventors: James N. Herron, Douglas A. Christensen, Jacob D. Durtschi
  • Patent number: 6108463
    Abstract: Improvements in a biosensor of the type having reservoirs or wells for analyzing a biological liquid are disclosed. A biosensor (190) includes a waveguide (164) placed between a plurality of members such as plates (100, 186), at least one of the members (100) being formed to define the walls (132, 134, 136) of the reservoirs where the liquid is biologically analyzed. The walls of the reservoirs are made of an inert, opaque material such as a metal. Although the biosensor may include a gasket (162), the gasket is associated with the members and waveguide in such a way (e.g. by recessing the gasket into a channel formed into a metal plate) so that the gasket does not form any significant portion of the reservoir wall. Waveguides of varying composition (e.g. plastic, quartz or glass) may be associated with the members to form the biosensor. The metal plate of the biosensor has input and output ports for infusing, draining, or oscillating the liquid to be analyzed in the reaction reservoir.
    Type: Grant
    Filed: September 18, 1998
    Date of Patent: August 22, 2000
    Assignee: University of Utah Research Foundation
    Inventors: James N. Herron, Douglas A. Christensen, Victor A. Pollak, Richard D. McEachern, Eric M. Simon
  • Patent number: 5961924
    Abstract: A step-gradient composite waveguide for evanescent sensing in fluorescent binding assays comprises a thick substrate layer having one or more thin film waveguide channels deposited thereon. In one embodiment, the substrate is silicon dioxide and the thin film is silicon oxynitride. Specific binding molecules having the property of binding with specificity to an analyte are immobilized on the surface of the thin film channels. In preferred embodiments, the composite waveguide further includes light input coupling means integrally adapted to the thin film channels. Such light coupling means can be a grating etched into the substrate prior to deposition of the thin film, or a waveguide coupler affixed to the upper surface of the thin film. The waveguide coupler has a thick input waveguide of high refractive index which receives the laser light through one end and propagates it by total internal reflection.
    Type: Grant
    Filed: October 31, 1997
    Date of Patent: October 5, 1999
    Assignee: University of Utah Research Foundation
    Inventors: W. Monty Reichert, James N. Herron, Douglas A. Christensen, Hsu-Kun Wang
  • Patent number: 5919712
    Abstract: Methods and apparatus for evanescent light fluoroimmunoassays are disclosed. The apparatus employs a planar waveguide with an integral semi-cylindrical lens, and has multi-analyte features and calibration features, along with improved evanescent field intensity. A preferred embodiment of the biosensor and assay method have patches of capture molecules each specific for a different analyte disposed adjacent within a single reservoir. The capture molecules are immobilized to the patches on the waveguide surface by site-specific coupling of thiol groups on the capture molecules to photo-affinity crosslinkers which in turn are coupled to the waveguide surface or to a non-specific-binding-resistant coating on the surface. The patches of different antibodies are produced by selectively irradiating a portion of the waveguide surface during the process of coupling the photo-affinity crosslinkers the selective irradiation involving a mask, a laser light source, or the like.
    Type: Grant
    Filed: November 13, 1996
    Date of Patent: July 6, 1999
    Assignee: University of Utah Research Foundation
    Inventors: James N. Herron, Douglas A. Christensen, Hsu-Kun Wang, Karin D. Caldwell, Vera Janatova, Shao-Chie Huang
  • Patent number: 5846842
    Abstract: Methods and apparatus for evanescent light fluoroimmunoassays are disclosed. The apparatus employs a planar waveguide and optionally has multi-well features and improved evanescent field intensity. The preferred biosensor and assay method have the capture molecules immobilized to the waveguide surface by site-specific coupling chemistry. Additionally, the coatings used to immobilize the capture molecules provide reduced non-specific protein adsorption.
    Type: Grant
    Filed: April 30, 1996
    Date of Patent: December 8, 1998
    Assignee: University of Utah Research Foundation
    Inventors: James N. Herron, Douglas A. Christensen, Karin D. Caldwell, Vera Janatova, Shao-Chie Huang, Hsu-Kun Wang
  • Patent number: 5832165
    Abstract: A step-gradient composite waveguide for evanescent sensing in fluorescent binding assays comprises a thick substrate layer having one or more thin film waveguide channels deposited thereon. In one embodiment, the substrate is silicon dioxide and the thin film is silicon oxynitride. Specific binding molecules having the property of binding with specificity to an analyte are immobilized on the surface of the thin film channels. In preferred embodiments, the composite waveguide further includes light input coupling means integrally adapted to the thin film channels. Such light coupling means can be a grating etched into the substrate prior to deposition of the thin film, or a waveguide coupler affixed to the upper surface of the thin film. The waveguide coupler has a thick input waveguide of high refractive index which receives the laser light through one end and propagates it by total internal reflection.
    Type: Grant
    Filed: August 28, 1996
    Date of Patent: November 3, 1998
    Assignee: University of Utah Research Foundation
    Inventors: W. Monty Reichert, James N. Herron, Douglas A. Christensen, Hsu-Kun Wang
  • Patent number: 5814565
    Abstract: A step-gradient composite waveguide for evanescent sensing in fluorescent binding assays comprises a thick substrate layer having one or more thin film waveguide channels deposited thereon. In one embodiment, the substrate is silicon dioxide and the thin film is silicon oxynitride. Specific binding molecules having the property of binding with specificity to an analyte are immobilized on the surface of the thin film channels. In preferred embodiments, the composite waveguide further includes light input coupling means integrally adapted to the thin film channels. Such light coupling means can be a grating etched into the substrate prior to deposition of the thin film, or a waveguide coupler affixed to the upper surface of the thin film. The waveguide coupler has a thick input waveguide of high refractive index which receives the laser light through one end and propagates it by total internal reflection.
    Type: Grant
    Filed: February 23, 1995
    Date of Patent: September 29, 1998
    Assignee: University of Utah Research Foundation
    Inventors: W. Monty Reichert, James N. Herron, Douglas A. Christensen, Hsu-Kun Wang
  • Patent number: 5751415
    Abstract: Apparatus and methods for analyzing the chemical composition of fluid streams using Raman spectroscopy are disclosed. The invention is particularly useful in continuously analyzing a fluid stream containing petroleum products, aqueous or biological fluids. The apparatus includes a laser source for producing light having an excitation wavelength. The light is introduced into a bundle of optical fibers connected to a tubular Raman enhancement cell. A transparent optical element (lens and/or window) acts as a barrier element to isolate the flowing sample stream from the optical components. The Raman enhancement cell is configured to allow continuous sample fluid flow therethrough, and it is preferably lined with a material having an index of refraction less than the index of refraction of the fluid stream. Scattered light from the enhancement cell preferably exits the optical fibers as a linear optical signal.
    Type: Grant
    Filed: May 13, 1996
    Date of Patent: May 12, 1998
    Assignee: Process Instruments, Inc.
    Inventors: Lee M. Smith, Robert E. Benner, Douglas A. Christensen, Joel M. Harris, Carl W. Johnson, Richard D. Rallison
  • Patent number: D426783
    Type: Grant
    Filed: April 19, 1999
    Date of Patent: June 20, 2000
    Assignees: University of Utah Research Foundation, IVD Systems, LLC
    Inventors: Douglas A. Christensen, James N. Herron, Eric M. Simon