Patents Assigned to GroupTek, Inc.
  • Apparatus and method of monitoring an analyte
    Patent number: 6576474
    Abstract: A detector for monitoring an analyte includes an analyte-sensing composition. The analyte-sensing composition has a visible color intensity or emission intensity (e.g., fluorescence intensity) that changes as the analyte concentration contacting the detector changes. The intensity changes can be visible to the human eye, or identified by an instrument. The analyte can include carbon dioxide, a volatile amine or a volatile carboxylic acid.
    Type: Grant
    Filed: August 5, 2002
    Date of Patent: June 10, 2003
    Assignee: GroupTek, Inc.
    Inventor: Donald F. H. Wallach
  • Apparatus and method of monitoring an analyte
    Publication number: 20030003593
    Abstract: A detector for monitoring an analyte includes an analyte-sensing composition. The analyte-sensing composition has a visible color intensity or emission intensity (e.g., fluorescence intensity) that changes as the analyte concentration contacting the detector changes. The intensity changes can be visible to the human eye, or identified by an instrument. The analyte can include carbon dioxide, a volatile amine or a volatile carboxylic acid.
    Type: Application
    Filed: August 5, 2002
    Publication date: January 2, 2003
    Applicant: GroupTek, Inc., a Delaware corporation
    Inventor: Donald F.H. Wallach
  • Methods and devices for detecting microbial spoilage in food products
    Patent number: 6495368
    Abstract: The present invention pertains to methods and devices for detecting microbial spoilage of a food product. The method involves placing a spoilage indicator device including a barrier sheet in fluid contact with a food product. The method also involves allowing any reactant molecule of a predetermined size produced in the food product by microbial spoilage to traverse the barrier sheet to contact a carrier of the device and to react with an indicator material therein. The method further provides observing the spoilage indicator to determine whether the detectable change has occurred in the indicator material. The detectable change indicates a build-up of the reactant molecule in the food product and therefore is indicative of microbial spoilage.
    Type: Grant
    Filed: November 5, 1996
    Date of Patent: December 17, 2002
    Assignee: GroupTek, Inc.
    Inventor: Donald F. H. Wallach
  • Apparatus and method of monitoring an analyte
    Patent number: 6428748
    Abstract: A detector for monitoring an analyte includes an analyte-sensing composition. The analyte-sensing composition has a visible color intensity or emission intensity (e.g., fluorescence intensity) that changes as the analyte concentration contacting the detector changes. The intensity changes can be visible to the human eye, or identified by an instrument. The analyte can include carbon dioxide, a volatile amine or a volatile carboxylic acid.
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: August 6, 2002
    Assignee: GroupTek, Inc.
    Inventor: Donald F. H. Wallach