Patents by Inventor Ritchard C. Parry

Ritchard C. Parry 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).

  • Solid-phase extraction tubes containing sulfonazide bonded-phase extractants
    Patent number: 5137626
    Abstract: The bonded phases generated from the reaction of aliphatic and aromatic azidosilanes with silica gel are suitable for use as packings in solid phase extraction columns for cleanup of urine samples for analysis of acid metabolites of cannabinoids. Such bonded phases are unique in their ability to selectively retain the acid metabolites of cannabinoids from a urine sample matrix.
    Type: Grant
    Filed: February 21, 1989
    Date of Patent: August 11, 1992
    Assignee: Rohm and Haas Company
    Inventors: Ritchard C. Parry, Daryl J. Gisch