Dionex Corporation

Bio-rad Laboratories, Inc.

Other

The Dow Chemical Company

The University of Texas System

Dionix Corporation

Christopher A. Pohl

Charanjit Saini

Christopher A Pohl

Kannan Srinivasan

Yan Liu

Nebojsa Avdalovic

Xiaodong Liu

John M Riviello

Rosanne Williamson Slingsby

Sheetal Bhardwaj

Andrei Bordunov

Jacek J Jagodzinski

Zhongqing Lu

Petr Jandik

Jinhua Chen

Victor Manuel Berber Barreto

Hamish Small

Rong Lin

Archava Siriraks

Victor Berber Barreto

Michael John McAdams

Bruce E Richter

John R Stillian

Jun Cheng

Maria A Rey

S M Rahmat Ullah

Manikandan Jayaraman

Neboisa Avdalovic

Xiadong Liu

Jing Hong

L Andy Woodruff

Roy D Rocklin

Mrinal Sengupta

Khosro Moshfegh

Shanhua Lin Liehr

Brian Dorich

Purnendu K Dasgupta

Nathan L Porter

Gary L Gleave

Sm Rahmat Ullah

Glenn Masami Kuse

Pil-Je Um

Charles Phillip Shelor

Paul R Haddad

Stephen S Heberling

Victor B Barretto

Victor M Barreto

Vernon E Summerfelt

Douglas M Jamieson

James R Thayer

Liang Cao

Brett Murphy

Brian A Jones

Milton Liu

John L Ezzell

Weixiong Huang

Mark Lee Tracy

Paul Raymond Haddad

William Dale Case

Edward L Johnson

Jung Un Baek

Walter Douglas Modic

Lawrence T McNary

Charaniit Saini

Charanijit Saini

Leilani Angers

Nebojsha Avdalovic

Harpreet S Dhillon

Melvin Hatch

Ryszard Gajek

Roseanne W Slingsby

Trung K Huynh

Frank Hoefler

Arachava Siriraks

Steven C Papanu

Udayanath Aich

Philip Zakaria

Brittany Omphroy

Michael Weitzhandler

Latha P Narayanan

Jeffrey S Rohrer

Laurence A Woodruff

John Edward Madden

Shanhua Lin

Andrei V Bordunov

Michael John Mcadams

Andy L Woodruff

Brittany K Omphroy

Saini Charanjit

Michael Mcadams

Victor Manuel Berber Baretto

Liu Xiaodong

A carrier for adsorption a compound, comprising a support; and a shrink-fitted monolithic body attached to and surrounding at least a portion of the support. The monolithic body can be porous and configured to bind compounds in a solution either for the isolation or depletion of the compounds from the solution.

Method for preparing monolithic coated surfaces

An ion exchange resin for use as a stationary phase in an ion chromatography column. The ion exchange resin has a negatively charged substrate particle, a positively charged polymer layer bound to the negatively charged substrate particle, a linker, and an ion exchange group. The ion exchange group includes a sulfonamide group and an amine, in which the ion exchange group is coupled to the positively charged polymer layer via the linker. When the sulfonamide is in a neutral form, a positively charged amine group provides retention; while when the sulfonamide is in an anionic form, the sulfonamide anion becomes a counter ion to the positively charged amine group, forming a zwitterion that reduces retention at that site. Accordingly, the retention time is able to be controlled by adjusting the mobile phase pH.

Sulfonamide based anion exchange resins

A chromatographic media for separating bio-polymers, the chromatographic media having cationic exchange properties and anionic exchange properties, the chromatographic media comprising: (a) non-porous substrate particles including an organic polymer, the substrate particles having a neutral hydrophilic layer at a surface of the non-porous substrate particles, in which the neutral hydrophilic layer is configured to reduce a binding of the bio-polymers directly to the non-porous substrate particles compared to a binding of the bio-polymer to the non-porous substrate particles without the neutral hydrophilic layer; (b) a charged first ion exchange layer bound to the substrate particles on top of the hydrophilic layer, the first ion exchange layer comprising first ion exchange groups; and (c) a charged second ion exchange layer bound to the substrate particles on top of the first ion exchange layer.

Multimodal chromatographic media for protein separation

Systems and methods for inhibiting translocation of ions across ion exchange barriers include an eluent generator having an ion source reservoir with a first electrode, an eluent generation chamber with a second electrode, an ion exchange barrier disposed therebetween, and means for reversing the polarity of a voltage or current applied across the first and second electrodes. A first polarity voltage or current applied across the electrodes generates an electric field that promotes translocation of eluent counter ions from the reservoir across the barrier, where the counter ions combine with eluent ions electrolytically generated in the chamber. By reversing the polarity of the voltage or current across the electrodes, the resulting electric field inhibits translocation of counter ions across the barrier from the reservoir into the chamber. Reverse voltage or current bias reduces counter ion concentration in the resting chamber to prevent exhaustion of ion suppressor capacity during start up.

Fast startup ion chromatography system and methods

A vial cap for removing a matrix component from a liquid sample is described. The vial cap includes a cap body, an inlet portion, and an outlet portion. The cap body is configured to have a slidable gas and liquid seal with a side wall of a sample vial. The inlet portion includes a counterbore section that holds a filter plug. The filter plug includes a polyethylene resin and a material selected from the group consisting of an ion exchange material and a reversed-phase material. The vial cap is adapted for solid phase extraction for use in an autosampler with a plurality of sample vials.

Vial cap and method for removing matrix components from a liquid sample

An electrochemical cell comprises a chamber, an inlet port, an outlet port, an electrode port, and a counter electrode. The inlet port is configured to allow flow of a liquid into the chamber and through an inlet opening toward the working electrode, and the outlet port is configured to allow flow of a liquid out of the chamber and through an outlet opening. The device is configured so that a force applied to the working electrode slides the first end face of the working electrode to a distance from a face of the inlet opening due to the balancing force of a fluid flowing out of the inlet opening. The device may be used in a method for analyzing an analyte, such as one or more amino acids in a liquid sample.

Electrochemical cell configured to have a dynamically renewed electrode

A coated substrate that comprises a polyolefin substrate having a functional polymer layer disposed thereon. The polyolefin substrate has a flow through pore structure with a pore size ranging from about 5 microns to about 250 microns. The functional polymer layer has a thickness ranging from about 1 micron to about 20 microns and a layer pore structure having a pore size ranging from about 1 nm to about 100 nm.

Coated poly-olefins

An anion exchange for separating a plurality of carbohydrates includes a negatively charged substrate particle. A base polymer layer includes a first plurality of quaternary amines. The polyalkylpolyamine polymer layer is covalently attached to the base condensation polymer layer. The polyalkylpolyamine polymer layer includes a polymeric branch structure that includes a second plurality of quaternary amines. A density of the second plurality of quaternary amines increases in a direction away from the base condensation polymer layer. The anion exchange stationary phase does not have a hydroxy group spaced apart from any one of the first or the second plurality of quaternary amines by an ethyl group.

Anion exchange stationary phases based on a polyalkylpolyamine polymer layer

A method of separating analytes in a liquid sample includes flowing the liquid sample through a chromatography column configured for use in liquid chromatography. The chromatography column contains a composition that includes a solid support having an exterior surface, a ligand, and a linker. The ligand includes a polyhedral oligomeric silsesquioxane moiety. The linker is covalently bound to both the polyhedral oligomeric silsesquioxane moiety and the exterior surface of the solid support.

Nanometer size chemical modified materials and uses

Ion exchange stationary phases are prepared with diprimary diamines for applications such as separating samples that contain polyvalent anions. The ion exchange stationary phase includes a series of condensation polymer reaction products bound to a substrate. The condensation polymer products are formed with diprimary diamines and polyepoxide compounds. The ion exchange stationary phases described herein are capable of separating monovalent and highly polyvalent anions relatively quickly with relatively low eluent concentrations in one chromatographic run.

Ion exchange stationary phases for analyzing polyvalent ions

An ion exchange chromatographic packing material is described that includes support resin particles and a copolymer grafted to the support resin particles. The copolymer includes polymerized functional monomers such as a first ion exchange group monomer and a second ion exchange group monomer. At a first pH, the first ion exchange group monomer is configured to have a first charge at a first pH, and the second ion exchange group monomer is configured to have a net neutral charge. At a second pH, the first ion exchange group monomer is configured to have the first charge at a second pH, and the second ion exchange group monomer is configured to have a second charge at the second pH where the first charge and second charge both have a same polarity.

Ion exchange chromatography column, method, and system thereof

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 (ClSOH), preferably from 85 wt % to 95 wt % chlorosulfonic acid at a process temperature of 20 to 25&#xb0; 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.

Functionalized polyolefin capillaries for open tubular ion chromatography

An ion exchange chromatography column contains an ion exchange stationary phase that includes a charged substrate, a plurality of first particles, and a plurality of second particles. The plurality of first particles each include first ion exchange groups and the first particles are ionically bound to the charged substrate. The plurality of second particles each include second ion exchange groups and the second particles are ionically bound to the charged substrate. The first particles having a first ion exchange group density, and the second particles having a second ion exchange group density. The first ion exchange group density is greater than the second ion exchange group density. The ion exchange chromatography column has a number of zones connected in series where each zone can have a varying level of first ion exchange groups and second ion exchange group from the inlet zone to the outlet zone.

Longitudinal gradient chromatography columns

Growing community of inventors

Union City, CA, United States of America

Christopher A Pohl