Patents by Inventor William J. Freytag

William J. 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).

  • Heterogeneous immunoassay for digoxin using ouabain as a separation means
    Patent number: 4551426
    Abstract: A heterogeneous immunoassay for digoxin. An excess of labeled anti-digoxin antibody is added to a test sample and the resulting reaction mixture is contacted with a solid phase having ouabain immobilized thereon. All the free, labeled antibody binds to the oubain. The eluted digoxin anti-digoxin antibody complex is measured for label activity. A competitive mode is also disclosed.
    Type: Grant
    Filed: January 18, 1984
    Date of Patent: November 5, 1985
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: William J. Freytag, Shung-Ho Chang