Patents by Inventor John Edward MADDEN

John Edward MADDEN 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).

  • METHOD FOR THE SEPARATION OF ANIONIC, CATIONIC, NEUTRAL AND ZWITTERIONIC ARSENIC SPECIES
    Publication number: 20240198255
    Abstract: A method comprising separating a plurality of arsenic species using a mixed mode column and a strong acid. The plurality of arsenic species includes at least one of each of an anionic arsenic species, a cationic arsenic species, a neutral arsenic species, and a zwitterionic arsenic species.
    Type: Application
    Filed: December 18, 2022
    Publication date: June 20, 2024
    Inventors: John Edward Madden, Charanjit Saini, Yan Liu
  • Current-efficient suppressor and pretreatment device and method
    Patent number: 10175211
    Abstract: An apparatus for treating an aqueous sample stream includes analyte ions. The apparatus comprises an ion exchange barrier; a sample stream flow channel; an ion receiving stream flow channel adjacent to the sample stream flow channel and separated therefrom by said first ion exchange bather. Stationary flow-through ion exchange packing is disposed in the sample flow channel of the same charge as the ion exchange bather. The ion exchange packing comprises a mixture of a first ion exchange portion with strong ionizable groups and a second ion exchange portion with weak ionizable groups of the same charge. First and second electrodes are in electrical communication with the sample stream flow channel and ion receiving flow channel.
    Type: Grant
    Filed: December 31, 2014
    Date of Patent: January 8, 2019
    Assignee: DIONEX CORPORATION
    Inventors: Kannan Srinivasan, Rong Lin, Christopher A. Pohl, John Edward Madden
  • CURRENT-EFFICIENT SUPPRESSOR AND PRETREATMENT DEVICE AND METHOD
    Publication number: 20160187305
    Abstract: An apparatus for treating an aqueous sample stream includes analyte ions. The apparatus comprises an ion exchange barrier; a sample stream flow channel; an ion receiving stream flow channel adjacent to the sample stream flow channel and separated therefrom by said first ion exchange bather. Stationary flow-through ion exchange packing is disposed in the sample flow channel of the same charge as the ion exchange bather. The ion exchange packing comprises a mixture of a first ion exchange portion with strong ionizable groups and a second ion exchange portion with weak ionizable groups of the same charge. First and second electrodes are in electrical communication with the sample stream flow channel and ion receiving flow channel.
    Type: Application
    Filed: December 31, 2014
    Publication date: June 30, 2016
    Inventors: Kannan SRINIVASAN, Rong LIN, Christopher A. POHL, John Edward MADDEN