Patents Assigned to Dionex Corporation
  • Patent number: 10048233
    Abstract: An apparatus for detecting analytes in a liquid sample may include an elongated primary channel through which an ionic species flows, the primary channel extending through a primary channel member, a first regenerant channel through which a regenerant flows, the first regenerant channel extending adjacent to the primary channel and being formed in a first block, a first charged barrier having exchangeable ions capable of passing ions of only one charge, positive or negative, and of blocking bulk liquid flow, the first charged barrier disposed between the primary channel member and the first block for separating the primary channel from the first regenerant channel, and a first sealing member disposed between the first charged barrier and the first block defining the first regenerant channel.
    Type: Grant
    Filed: November 12, 2012
    Date of Patent: August 14, 2018
    Assignee: DIONEX CORPORATION
    Inventors: Kannan Srinivasan, Glenn M. Kuse, Rong Lin, Sheetal Bhardwaj
  • Patent number: 10023965
    Abstract: Buffer generators are described based on electrodialytic devices. The methods of using these devices can generate buffers for diverse applications, including separations, e.g., HPLC and ion chromatography. Also provided are chromatographic devices including the buffer generators, generally located upstream from a chromatography column, sample injector valve or both.
    Type: Grant
    Filed: August 23, 2012
    Date of Patent: July 17, 2018
    Assignees: Board of Regents, The University of Texas System, Dionex Corporation
    Inventors: Purnendu K. Dasgupta, Yongjing Chen, Kannan Srinivasan
  • Patent number: 9976994
    Abstract: A system reduces unwanted noise due to pump movement. The system includes a pump including a non-conductive piston extending into a pumping chamber for pumping the sample fluid along an analysis fluid path, a wash chamber, and a seal fluidly separating the pumping chamber from the wash chamber. The system also includes a wash path supplying a wash fluid from a wash reservoir to the wash chamber, an electrical conductor electrically connecting the analysis fluid path to the wash fluid path, and a ground conductor electrically connecting the electrical conductor to ground via a resistor. The electrical conductors and resistor combination between the chambers reduces unwanted noise in the conductivity detector due voltage potentials between the eluent and wash chambers created as the piston moves between the chambers.
    Type: Grant
    Filed: August 28, 2015
    Date of Patent: May 22, 2018
    Assignee: DIONEX CORPORATION
    Inventors: Michael J. McAdams, Ihab Elzind
  • Patent number: 9964510
    Abstract: An electrolytic device includes four channels separated by three charged barriers. The device can be used to suppress an eluent stream containing separated sample analyte ions and/or to pretreat a sample stream containing unseparated analyte ions.
    Type: Grant
    Filed: September 16, 2013
    Date of Patent: May 8, 2018
    Assignee: DIONEX CORPORATION
    Inventors: Kannan Srinivasan, Sheetal Bhardwaj, Rong Lin
  • Publication number: 20180093262
    Abstract: Open tubular capillary columns for liquid and ion chromatography, based upon an ionically impermeable polyolefin capillary having a bore with a sulfonate-group- or amine-group-functionalized internal surface. The capillary columns may include a coating of ion exchanging nanoparticles electrostatically bound to the functionalized internal surface. The capillary columns may be made by exposing the interior surface to a sulfonating reagent comprising chlorosulfonic acid (ClSO3H), preferably from 85 wt % to 95 wt % chlorosulfonic acid at a process temperature of 20 to 25° C. The interior surface may be subsequently exposed to an asymmetrical diamine to form a sulfonic mid-linkage to the diamine, i.e., to form a sulfonamide-linked, amine-group-functionalized internal surface. The coating may be provided by subsequently exposing the interior surface to an aqueous suspension of ion exchanging nanoparticles to electrostatically bond the ion exchanging nanoparticles to the functionalized internal surface.
    Type: Application
    Filed: December 30, 2016
    Publication date: April 5, 2018
    Applicants: The Board of Regents, University of Texas System, Dionex Corporation
    Inventors: Purnendu K. DASGUPTA, Weixiong HUANG, Christopher A. POHL
  • Patent number: 9931585
    Abstract: An electrolytic device comprising a housing includes at least first and second adjacent liquid flow-through channels. A barrier impermeable to ion flow and to bulk liquid flow is disposed between the first and second channels. A first electrode assembly is disposed adjacent to one end of the channels and a second electrode assembly is disposed adjacent the other end of the channels. Also, a contaminant removal method using the above electrolytic device. A first aqueous stream including contaminants flows through the first channel while passing a current between the first and second electrode assemblies to remove contaminants. Effluent from the first channel flows, with or without further treatment, through the second channel while passing current between said first and second electrode assemblies to remove further contaminants.
    Type: Grant
    Filed: April 23, 2014
    Date of Patent: April 3, 2018
    Assignee: DIONEX CORPORATION
    Inventor: Kannan Srinivasan
  • Patent number: 9914651
    Abstract: A sandwich suppressor in an ion chromatography system in which loosely packed ion exchange resin of low density is disposed in the central sample stream flow channel. Also, a method of using the suppressor is described.
    Type: Grant
    Filed: May 8, 2013
    Date of Patent: March 13, 2018
    Assignee: DIONEX CORPORATION
    Inventors: Kannan Srinivasan, Christopher A. Pohl, Sheetal Bhardwaj, Rong Lin
  • Publication number: 20180008959
    Abstract: A chromatographic material including a substrate having a surface and having a polymeric layer covalently bound to the surface; the polymeric layer comprising polymer molecules covalently attached to the surface of the substrate, each polymer molecule being attached to the surface via multiple siloxane bonds and each polymer molecule being connected to one or more functionalizing compounds that each comprise a functional group, wherein the polymeric layer is formed by covalently attaching polymer molecules to the surface of the substrate via multiple siloxane bonds, each polymer molecule containing multiple first reactive groups, and reacting the first reactive groups of the attached polymer molecules with at least one functionalizing compound that comprises a second reactive group that is reactive with the first reactive groups and that further comprises a functional group. Preferred conditions of reacting the polymer with the substrate include elevated temperature and reduced pressure.
    Type: Application
    Filed: January 12, 2016
    Publication date: January 11, 2018
    Applicant: Dionex Corporation
    Inventors: Xiaodong LIU, Xiao CUI, Xuefei SUN
  • Patent number: 9851333
    Abstract: A nebulizer for a charged aerosol detection (CAD) system is disclosed. The nebulizer is provided with a spray emitter for generating a spray of droplets within a central region of a spray chamber. The central region is separated from an upper region by a horizontally projecting rib, which defines a passageway between the central and upper regions. The major direction of droplet travel within the upper region is substantially reversed with respect to the major direction of droplet travel within the central region. Larger droplets are unable to negotiate the turn from the central to upper regions and impinge on a rear surface of the spray chamber. Removal of larger droplets has the advantageous effect of enabling the detector to sense a smaller range of particle sizes, which establishes a relatively steady electrical current at the detector.
    Type: Grant
    Filed: May 28, 2014
    Date of Patent: December 26, 2017
    Assignee: Dionex Corporation
    Inventors: Alan Daniel Yim, Paul H. Gamache, Ryan S. McCarthy
  • Patent number: 9804136
    Abstract: An automated method of calibrating a chromatography system and analyzing a sample is described. The method includes forming diluted standard solutions that are injected into a chromatography column. The detected peaks can be identified based on a first predetermined calibration ratio associated with the standard solution. Once the chromatography system is calibrated, samples can be chromatographically analyzed where the measured peaks are identified and quantified in an automated manner.
    Type: Grant
    Filed: September 18, 2014
    Date of Patent: October 31, 2017
    Assignee: DIONEX CORPORATION
    Inventors: Kannan Srinivasan, Christopher A. Pohl
  • Patent number: 9739692
    Abstract: Apparatus for extracting organic analytes from a sample comprising a first compressed gas source connected to valving and a sample extraction cell connected to the valving. A pressure regulator is connected to the extraction cell outlet to the pressure regulator. The pressure regulator blocks fluid flow when the pressure at the pressure regulator inlet is below a predetermined pressure and permits fluid flow when above said predetermined pressure. The apparatus is free of operative association with a mechanical pump or with a compressed gas source other than the compressed gas source. An extraction method for using the above apparatus is described.
    Type: Grant
    Filed: March 27, 2015
    Date of Patent: August 22, 2017
    Assignee: Dionex Corporation
    Inventors: Kannan Srinivasan, S M Rahmat Ullah
  • Patent number: 9733170
    Abstract: A method of extracting an analyte from a sample is described where the sample includes water. The sample and polymeric drying agent are added to a container. The polymeric drying agent includes a cationic monomer, an anionic monomer, and a crosslinker. The polymeric drying agent is configured to sorb water from the sample.
    Type: Grant
    Filed: September 8, 2016
    Date of Patent: August 15, 2017
    Assignee: Dionex Corporation
    Inventors: Christopher A. Pohl, Kannan Srinivasan, S M Rahmat Ullah
  • Patent number: 9664655
    Abstract: Electrolytic eluent recycle systems for ion chromatography using a multi-channel electrolytic ion exchange device which integrates suppression, eluent generation, and eluent recycle. The systems recycle the eluent into the analytical system without passing the eluent through the electrode chambers. Also, such systems with a channel for electrolytic removal of ions from the suppression effluent before recycle.
    Type: Grant
    Filed: December 2, 2013
    Date of Patent: May 30, 2017
    Assignee: Dionex Corporation
    Inventor: John M. Riviello
  • Patent number: 9645124
    Abstract: Method and apparatus for generating an acid or base, e.g. for chromatographic analysis of anions. For generating a base the method includes the steps of providing a cation source in a cation source reservoir, flowing an aqueous liquid stream through a base generation chamber separated from the cation source reservoir by a barrier (e.g. a charged membrane) substantially preventing liquid flow while providing a cation transport bridge, applying an electric potential between an anode cation source reservoir and a cathode in the base generation chamber to electrolytically generate hydroxide ions therein and to cause cations in the cation source reservoir to electromigrate and to be transported across the barrier toward the cathode to combine with the transported cations to form cation hydroxide, and removing the cation hydroxide in an aqueous liquid stream as an effluent from the first base generation chamber. Suitable cation sources include a salt solution, a cation hydroxide solution or cation exchange resin.
    Type: Grant
    Filed: January 10, 2013
    Date of Patent: May 9, 2017
    Assignee: DIONEX CORPORATION
    Inventors: Yan Liu, Hamish Small, Nebojsa Avdalovic
  • Patent number: 9625430
    Abstract: An electrolytic device comprising: a central sample flow channel, first and second regenerant flow channels, first and second charged barriers disposed between said sample flow channel and first and second regenerant flow channels, and pairs of oppositely charged, spaced electrodes disposed in the regenerant flow channels. Also, electrolytic devices with a different electrode configuration are described. Also, methods of using the devices, e.g., for suppression in an ion chromatography system are described.
    Type: Grant
    Filed: October 18, 2013
    Date of Patent: April 18, 2017
    Assignee: DIONEX CORPORATION
    Inventors: Kannan Srinivasan, Sheetal Bhardwaj, Rong Lin
  • Patent number: 9624588
    Abstract: A system and method to generate a concentration gradient eluent flow are described. The concentration gradient eluent flow can include at least two different generants. A liquid can be pumped to an eluent generating device. A first controlling signal can be applied to a first eluent generator to generate a first generant. A second controlling signal can be applied to a second eluent generator to generate a second generant. Either the first and/or the second controlling signal can be varied as a function of time to generate the concentration gradient eluent flow.
    Type: Grant
    Filed: June 15, 2015
    Date of Patent: April 18, 2017
    Assignee: Dionex Corporation
    Inventors: Yan Liu, Petr Jandik, Christopher A. Pohl
  • Patent number: 9592458
    Abstract: A method of making an ion exchange foam is described. The method includes forming an aqueous phase by suspending an ion exchange resin in an aqueous solvent. An organic phase is formed by mixing at least a divinylbenzene, a monomer, and a surfactant. The formed aqueous phase is mixed with the formed organic phase to form an emulsion. The emulsion is polymerized to form the ion exchange foam. The ion exchange foam can be used with a plurality of sample vials in an autosampler.
    Type: Grant
    Filed: December 26, 2013
    Date of Patent: March 14, 2017
    Assignee: DIONEX CORPORATION
    Inventors: Christopher A. Pohl, Rosanne W. Slingsby, Jing Hong
  • Patent number: 9580822
    Abstract: An electrodialytic buffer generator is described. The buffer generator may include a central buffer-generating channel having an inlet and outlet, a second chamber, and a third chamber. The buffer-generating channel, the second chamber, and the third chamber may each include an electrode. The buffer generator may also include a first ion exchange barrier and a second ion exchange barrier. The first ion exchange barrier can be disposed between the second chamber and the buffer-generating channel. The second ion exchange barrier can be disposed between the third chamber and the buffer-generating channel.
    Type: Grant
    Filed: August 23, 2012
    Date of Patent: February 28, 2017
    Assignees: Board of Regents, The University of Texas System, Dionex Corporation
    Inventors: Purnendu K. Dasgupta, Yongjing Chen, Kannan Srinivasan
  • Patent number: 9486799
    Abstract: Treatment of anion exchange materials containing hydroxyl containing moieties in the beta position relative to the quaternary center in the hydroxide form with glycidol substantially alters the selectivity of the anion exchange material. Furthermore, sequential treatments of first a hydroxide containing solution to put the anion exchange material in the hydroxide form followed by treatment with glycidol in an alternating sequence progressively changes selectivity in a predictable manner allowing facile manipulation of selectivity. Unique to the selectivities achievable with this chemistry is the ability to reverse the elution order of sulfate and carbonate. With all other known systems, carbonate elutes ahead of sulfate and sometimes compromises the ability to quantitate sulfate. With glycidol treatment, carbonate can be moved after sulfate which eliminates interference issues for samples containing significantly more carbonate than sulfate.
    Type: Grant
    Filed: September 11, 2012
    Date of Patent: November 8, 2016
    Assignee: DIONEX CORPORATION
    Inventor: Christopher A. Pohl
  • Patent number: 9459184
    Abstract: A method of extracting an analyte from a sample is described where the sample includes water. The sample and polymeric drying agent are added to a container. The polymeric drying agent includes a cationic monomer, an anionic monomer, and a crosslinker. The polymeric drying agent is configured to sorb water from the sample.
    Type: Grant
    Filed: March 8, 2012
    Date of Patent: October 4, 2016
    Assignee: DIONEX CORPORATION
    Inventors: Christopher A. Pohl, Kannan Srinivasan, S M Rahmat Ullah