Patents by Inventor David Lingenfelter

David Lingenfelter 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).

  • Cross-linked polypeptide fragments of .beta.-galactosidase
    Patent number: 5976857
    Abstract: Formation of an intramolecular cross-link in enzyme donor polypeptide fragments of .beta.-galactosidase, thereby forming a cyclic enzyme donor which is hindered from complementation with an enzyme acceptor fragment to form active of .beta.-galactosidase. The cyclic enzyme donor can be linearized by cleaving to restore complementation ability. Assays in which such cyclic enzyme donors are linearized by specific analytes are disclosed, as well as novel homobifunctional bis-maleimido cross-linking agents of the formula ##STR1## wherein R is hydroxy or acetate.
    Type: Grant
    Filed: January 26, 1996
    Date of Patent: November 2, 1999
    Assignee: Boehringer Mannheim Corporation
    Inventors: Michael J. Powell, Pyare Khanna, Scott J. Eisenbeis, David Lingenfelter, Lutz F. Tietze
  • Assays using cross-linked polypeptide fragments of .beta.-galactosidase
    Patent number: 5763196
    Abstract: Formation of an intramolecular cross-link in enzyme donor polypeptide fragments of .beta.-galactosidase, thereby forming a cyclic enzyme donor which is hindered from complementation with an enzyme acceptor fragment to form active of .beta.-galactosidase. The cyclic enzyme donor can be linearized by cleaving to restore complementation ability. Assays in which such cyclic enzyme donors are linearized by specific analytes are disclosed, as well as novel homobifunctional bis-maleimido cross-linking agents of the formula ##STR1## wherein R is hydroxy or acetate.
    Type: Grant
    Filed: January 26, 1996
    Date of Patent: June 9, 1998
    Assignee: Boehringer Mannheim Corporation
    Inventors: Michael J. Powell, Pyare Khanna, David Lingenfelter, Scott J. Eisenbeis