Patents by Inventor Christopher A. Pohl

Christopher A. Pohl 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).

  • Sample pretreatment and extraction
    Patent number: 8507292
    Abstract: A method for pretreating and extracting a liquid sample by sorbing an aqueous liquid sample, including an organic analyte and an acid or a base, in a solid sorbent material, and at least partially neutralizing the acid or base by reaction with neutralizing ions retained on a support surface, and contacting the liquid sample-sorbed sorbent material at elevated temperature and pressure with an organic solvent to extract the analyte into said solvent, preferably in a vessel having an extraction chamber with a zirconium metal interior surface.
    Type: Grant
    Filed: July 1, 2011
    Date of Patent: August 13, 2013
    Assignee: Dionex Corporation
    Inventors: Kannan Srinivasan, Bruce Richter, Christopher A. Pohl, Brett Murphy, Brian Dorich, S. M. Rahmat Ullah
  • CAPILLARY ION CHROMATOGRAPHY
    Publication number: 20130180922
    Abstract: An apparatus for capillary ion chromatography comprising a suppressor comprising flow-through ion exchange packing in a housing and capillary tubing formed of a permselective ion exchange membrane, and at least partially disposed in said ion exchange packing. Also, a recycle conduit for aqueous liquid from the detector to the packing. Further, the capillary tubing may have weakly acidic or weakly basic functional groups. Also, a method for using the apparatus.
    Type: Application
    Filed: March 6, 2013
    Publication date: July 18, 2013
    Inventors: Yan LIU, Victor Manuel Berber BARRETO, Christopher A. POHL, Nebojsa AVDALOVIC
  • Ion chromatography systems with flow-delay eluent recycle
    Patent number: 8465982
    Abstract: A chromatographic method including chromatographically separating sample ionic species in an eluent stream, detecting the separated sample ionic species, catalytically combining hydrogen and oxygen gases or catalytically decomposing hydrogen peroxide in a catalytic gas elimination chamber, and recycling the effluent stream from the chamber to the chromatography separation column. The residence time between the detector and the chamber is at least about one minute. Also, flowing the recycle sequentially through two detector effluent flow channels of an electrolytic membrane suppressor. Also, applying heat or UV energy between the detector and the chamber. Also, detecting bubbles after the chamber. Also, a Platinum group metal catalyst and ion exchange medium in the chamber. Apparatus for performing the methods.
    Type: Grant
    Filed: March 29, 2011
    Date of Patent: June 18, 2013
    Assignee: Dionex Corporation
    Inventors: Yan Liu, Kannan Srinivasan, Christopher A. Pohl, Sheetal Bhardwaj, Zhongqing Lu
  • Organosilanes and substrate bonded with same
    Patent number: 8425778
    Abstract: The present invention provides novel silicon compounds, methods for making these novel silicon compounds, compositions comprising these novel silicon compounds attached to substrates, methods for attaching the novel silicon compounds to substrates and methods for using the compositions in a variety of chromatographic applications.
    Type: Grant
    Filed: May 4, 2012
    Date of Patent: April 23, 2013
    Assignee: Dionex Corporation
    Inventors: Xiadong Liu, Christopher A. Pohl, Andrei V. Bordunov, Nebojsa Avdalovic
  • ELECTROCHEMICAL DETECTION CELL FOR LIQUID CHROMATOGRAPHY SYSTEM
    Publication number: 20130091936
    Abstract: A detection cell for a chromatography system includes a cell body having an inlet, an outlet, and a counter electrode, a working electrode, a sample flow passageway extending between the inlet and the outlet and in fluid contact with the counter and working electrodes, and a palladium/noble metal reference electrode system. A method of using the detection cell is also described.
    Type: Application
    Filed: November 30, 2012
    Publication date: April 18, 2013
    Inventors: Jun CHENG, Petr JANDIK, Christopher A. POHL
  • High pressure degas assembly for chromatography system and method
    Patent number: 8414684
    Abstract: A degas assembly including a low pressure fluid channel for carrying a wash fluid at a first pressure, a pressurized channel for carrying eluent including a gas at a second pressure higher than the first pressure, and a degas separator defining a fluid barrier between the low pressure fluid channel and pressurized fluid channel, the separator configured to retain liquid in the pressurized fluid channel and allow gas to flow through the separator to the low pressure fluid channel. The pressurized fluid channel may extend along an outer periphery of the low pressure fluid channel. The eluent may be received from an eluent generator at a pressure of at least about 3300 psi, and in various embodiments up to about 5000 psi. A liquid chromatography system and method are also disclosed.
    Type: Grant
    Filed: June 1, 2010
    Date of Patent: April 9, 2013
    Assignee: Dionex Corporation
    Inventors: Yan Liu, Christopher A. Pohl, Michael McAdams, Hamish Small, Zhongqing Lu, Milton Liu, Khosro Moshfegh
  • Capillary ion chromatography
    Patent number: 8415168
    Abstract: An apparatus for capillary ion chromatography comprising a suppressor comprising flow-through ion exchange packing in a housing and capillary tubing formed of a permselective ion exchange membrane, and at least partially disposed in said ion exchange packing. Also, a recycle conduit for aqueous liquid from the detector to the packing. Further, the capillary tubing may have weakly acidic or weakly basic functional groups. Also, a method for using the apparatus.
    Type: Grant
    Filed: May 23, 2012
    Date of Patent: April 9, 2013
    Assignee: Dionex Corporation
    Inventors: Yan Liu, Victor Manuel Berber Barreto, Christopher A. Pohl, Nebojsa Avdalovic
  • ORGANOSILANES AND SUBSTRATE BONDED WITH SAME
    Publication number: 20130026099
    Abstract: The present invention provides novel silicon compounds, methods for making these novel silicon compounds, compositions comprising these novel silicon compounds attached to substrates, methods for attaching the novel silicon compounds to substrates and methods for using the compositions in a variety of chromatographic applications.
    Type: Application
    Filed: May 4, 2012
    Publication date: January 31, 2013
    Applicant: Dionex Corporation
    Inventors: Xiadong Liu, Christopher A. Pohl, Andrei V. Bordunov, Nebojsa Avdalovic
  • Electrochemical detection cell for liquid chromatography system
    Patent number: 8342007
    Abstract: A detection cell for a chromatography system includes a cell body having an inlet, an outlet, and a counter electrode, a working electrode, a sample flow passageway extending between the inlet and the outlet and in fluid contact with the counter and working electrodes, and a palladium/noble metal reference electrode system. A method of using the detection cell is also described.
    Type: Grant
    Filed: February 10, 2010
    Date of Patent: January 1, 2013
    Assignee: Dionex Corporation
    Inventors: Jun Cheng, Petr Jandik, Christopher A. Pohl
  • Ion chromatography system using catalytic gas elimination
    Patent number: 8308952
    Abstract: A liquid chromatographic system is provided including catalytically combining hydrogen and oxygen gases in the chromatography eluent stream in a catalytic gas elimination chamber, to form water and thereby reduce the gas content in the eluent stream. Also, a liquid ion chromatographic system in which the effluent from the detector is recycled to a membrane suppressor and then is mixed with a source of eluent for recycle to the chromatographic column.
    Type: Grant
    Filed: May 25, 2012
    Date of Patent: November 13, 2012
    Assignee: Dionex Corporation
    Inventors: Yan Liu, Christopher A. Pohl, Nebojsa Avdalovic, John M. Riviello, Arachava Siriraks
  • ION CHROMATOGRAPHY SYSTEM USING CATALYTIC GAS ELIMINATION
    Publication number: 20120255910
    Abstract: A liquid chromatographic system is provided including catalytically combining hydrogen and oxygen gases in the chromatography eluent stream in a catalytic gas elimination chamber, to form water and thereby reduce the gas content in the eluent stream. Also, a liquid ion chromatographic system in which the effluent from the detector is recycled to a membrane suppressor and then is mixed with a source of eluent for recycle to the chromatographic column.
    Type: Application
    Filed: May 25, 2012
    Publication date: October 11, 2012
    Applicant: DIONEX CORPORATION
    Inventors: Yan Liu, Christopher A. Pohl, Nebojsa Avdalovic, John M. Riviello, Archava Siriraks
  • ELECTROSTATICALLY BOUND HYPERBRANCHED ANION EXCHANGE SURFACE COATING PREPARED VIA CONDENSATION POLYMERIZATION USING DITERTIARY AMINE LINKERS FOR IMPROVED DIVALENT ANION SELECTIVITY
    Publication number: 20120231195
    Abstract: The present invention provides a new design for high capacity stationary phases for dianion selective ion chromatography. The stationary phases include one or more layers which are products of condensation polymerization. Multiple components are of use in forming the first polymer layer and the condensation polymer structure, thereby providing a stationary phase that can be engineered to have a desired property such as ion capacity, ion selectivity, and the like. Exemplary condensation polymers are formed by the reaction of at least one polyfunctional compound with at least one compound of complimentary reactivity, e.g., a nucleophilic polyfunctional compound reacting with an electrophilic compound.
    Type: Application
    Filed: March 9, 2012
    Publication date: September 13, 2012
    Applicant: Dionex Corporation
    Inventors: Christopher A. Pohl, Kannan Srinivasan, Sheetal Bhardwaj
  • CAPILLARY ION CHROMATOGRAPHY
    Publication number: 20120228227
    Abstract: An apparatus for capillary ion chromatography comprising a suppressor comprising flow-through ion exchange packing in a housing and capillary tubing formed of a permselective ion exchange membrane, and at least partially disposed in said ion exchange packing. Also, a recycle conduit for aqueous liquid from the detector to the packing. Further, the capillary tubing may have weakly acidic or weakly basic functional groups. Also, a method for using the apparatus.
    Type: Application
    Filed: May 23, 2012
    Publication date: September 13, 2012
    Applicant: DIONEX CORPORATION
    Inventors: Yan Liu, Victor Manuel Berber Barreto, Christopher A. Pohl, Nebojsa Avdalovic
  • NANOMETER SIZE CHEMICAL MODIFIED MATERIALS AND USES
    Publication number: 20120205315
    Abstract: There are provided ligand compositions and stationary phases comprising a polyhedral oligomeric silsequioxane moiety. Also provided are chromatographic devices comprising the stationary phases, and methods of making and using the ligands, stationary phases and chromatographic devices of the invention.
    Type: Application
    Filed: February 14, 2012
    Publication date: August 16, 2012
    Applicant: Dionex Corporation
    Inventors: Xiaodong Liu, Christopher A. Pohl
  • Capillary ion chromatography
    Patent number: 8216515
    Abstract: An apparatus for capillary ion chromatography having a suppressor having flow-through ion exchange packing in a housing and capillary tubing formed of a permselective ion exchange membrane, and at least partially disposed in said ion exchange packing. Also, a recycle conduit for aqueous liquid from the detector to the packing. Further, the capillary tubing may have weakly acidic or weakly basic functional groups. Also, a method for using the apparatus.
    Type: Grant
    Filed: September 16, 2004
    Date of Patent: July 10, 2012
    Assignee: Dionex Corporation
    Inventors: Yan Liu, Victor Manuel Berber Barreto, Christopher A. Pohl, Nebojsa Avdalovic
  • CHEMICAL SUPPRESSORS AND METHOD OF USE
    Publication number: 20120141328
    Abstract: A non-electrolytic method and apparatus for treating an aqueous sample stream including analyte ions and matrix ions of opposite charge, for pretreatment or suppression. The apparatus includes an ion exchange membrane capable of passing only ions of opposite charge to the analyte ions, a sample stream flow channel, a first aqueous stream ion receiving flow channel adjacent one side of the sample stream flow channel and separated therefrom by the first ion exchange membrane, and stationary flow-through ion exchange packing disposed in the sample stream flow channel. The ion receiving channel has an ion exchange capacity for the matrix ions less than about 25% of the ion exchange capacity for the matrix ions.
    Type: Application
    Filed: February 8, 2012
    Publication date: June 7, 2012
    Applicant: Dionex Corporation
    Inventors: Kannan SRINIVASAN, Christopher A. POHL
  • ELECTROCHEMICALLY DRIVEN PUMP
    Publication number: 20120138474
    Abstract: A continuous electrochemical pump comprising a water generator compartment, an anode compartment on one side of said generator compartment, a cation exchange barrier, separating the generator compartment from the anode compartment, it first electrode in electrical communication with the anode compartment, a cathode compartment adjacent the generator chamber, an anion exchange barrier, separating the generation compartment from the cathode compartment, and a second electrode in electrical communication with the cathode compartment. Use of the pump as a sample concentrator. A feedback loop for the pump. A reservoir, with or without an intermediate piston, on the output side of the pump.
    Type: Application
    Filed: February 1, 2012
    Publication date: June 7, 2012
    Applicant: Dionex Corporation
    Inventors: Hamish Small, Yan Liu, Christopher A. Pohl
  • Organosilanes and substrate bonded with same
    Patent number: 8182679
    Abstract: The present invention, provides novel silicon compounds, methods for making these novel silicon compounds, compositions comprising these novel silicon compounds attached to substrates, methods for attaching the novel silicon compounds to substrates and methods for using the compositions in a variety of chromatographic applications.
    Type: Grant
    Filed: April 28, 2008
    Date of Patent: May 22, 2012
    Assignee: Dionex Corporation
    Inventors: Xiaodong Liu, Christopher A. Pohl, Andrei V. Bordunov, Nebojsa Avdalovic
  • Electrochemically driven pump
    Patent number: 8133373
    Abstract: A continuous electrochemical pump comprising a water generator compartment, an anode compartment on one side of said generator compartment, a cation exchange barrier, separating the generator compartment from the anode compartment, a first electrode in electrical communication with the anode compartment, a cathode compartment adjacent the generator chamber, an anion exchange barrier, separating the generation compartment from the cathode compartment, and a second electrode in electrical communication with the cathode compartment. Use of the pump as a sample concentrator. A feedback loop for the pump. A reservoir, with or without an intermediate piston, on the output side of the pump.
    Type: Grant
    Filed: August 15, 2008
    Date of Patent: March 13, 2012
    Assignee: Dionex Corporation
    Inventors: Hamish Small, Yan Liu, Christopher A. Pohl
  • SAMPLE PRETREATMENT AND EXTRACTION
    Publication number: 20120028368
    Abstract: A method for pretreating and extracting a liquid sample by sorbing an aqueous liquid sample, including an organic analyte and an acid or a base, in a solid sorbent material, and at least partially neutralizing the acid or base by reaction with neutralizing ions retained on a support surface, and contacting the liquid sample-sorbed sorbent material at elevated temperature and pressure with an organic solvent to extract the analyte into said solvent, preferably in a vessel having an extraction chamber with a zirconium metal interior surface.
    Type: Application
    Filed: July 1, 2011
    Publication date: February 2, 2012
    Applicant: Dionex Corporation
    Inventors: Kannan Srinivasan, Bruce Richter, Christopher A. Pohl, Brett Murphy, Brian Dorich, S.M. Rahmat Ullah