Patents by Inventor J. William Freytag

J. William Freytag 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).

  • Patent number: 4657853
    Abstract: An enzyme is cross linked to form a polymerized enzyme which is covalently coupled to an antibody or antibody fragment. The use of the antibody-polymeric enzyme conjugate in immunoassays provides enhanced signal generation and, therefore, short assay time and high sensitivity.
    Type: Grant
    Filed: September 14, 1984
    Date of Patent: April 14, 1987
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: J. William Freytag, Eiji Ishikawa
  • Patent number: 4517303
    Abstract: A novel analyte-cytolysin conjugate and its use in a lipid vesicle mediated measurement process is described for a wide variety of analytes present at very low concentration. The method involves forming a reaction system consisting of analyte, analyte specific binding agent, analyte-cytolysin conjugate, and vesicles containing detectable marker material in such proportions that uncombined conjugate alters the permeability of the vesicles resulting in the release and quantitative detection of marker material which can be correlated with the amount of analyte initially present.
    Type: Grant
    Filed: October 20, 1982
    Date of Patent: May 14, 1985
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: J. William Freytag, William J. Litchfield
  • Patent number: 4434236
    Abstract: A method for the rapid determination of analyte in a sample is provided. The sample is contacted with a solid phase having immobilized thereon an analyte-analogue to which there is displaceably bound a labeled anti-analyte antibody. Because the antibody has greater affinity for the analyte than the analyte-analogue, the labeled antibody is displaced from the solid phase. The complex is separated from the solid phase, and the amount of complex is measured. The measured amount is related to the amount of analyte initially present in the sample.
    Type: Grant
    Filed: October 20, 1982
    Date of Patent: February 28, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: J. William Freytag