Patent application number | Description | Published |
20080203027 | Organosilanes and substrate bonded with same - 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. | 08-28-2008 |
20080293959 | COMPOSITIONS USEFUL AS CHROMATOGRAPHY STATIONARY PHASES - The current invention provides compositions, which are useful as stationary phases for a variety of chromatographic applications, such as high performance liquid chromatography (HPLC). The compositions include a substrate (e.g., silica gel), covalently bound to a compound, which includes both a hydrophobic moiety and a hydrophilic moiety, which is preferably a 1,2-diol moiety. The hydrophobic moiety is sufficiently hydrophobic for the compositions to exhibit reversed phase characteristics and typically incorporates at least 5 carbon atoms in sequence. Based on having both hydrophilic and hydrophobic functionalities, the new stationary phases exhibit unique chromatographic properties. For example, these media can be used in either hydrophilic (HILIC) mode, in which the mobile phase includes a high percentage of an organic solvent, or in reversed phase mode, in which the mobile phase contains a higher percentage of an aqueous solvent. The current invention also provides methods of making and using the compounds and compositions of the invention. | 11-27-2008 |
20090101582 | Recycled Suppressor Regenerants - A suppressed ion chromatographic apparatus using a regenerant recycle loop, comprising (a) an ion separation device, (b) a membrane suppressor, (c) a detector, (d) a container for regenerant solution, (e) a first conduit between the ion separation device and the suppressor, (f) a second conduit between the regenerant solution container and the suppressor, (g) a third conduit between the suppressor and the regenerant solution container, and (h) a regenerant solution recycle loop out of fluid communication with the detector outlet. | 04-23-2009 |
20090130767 | ORGANOSILANES AND SUBSTRATES COVALENTLY BONDED WITH SAME AND METHODS FOR SYNTHESIS AND USE - 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. | 05-21-2009 |
20090166293 | CHEMICAL SUPPRESSORS AND METHOD OF USE - 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. | 07-02-2009 |
20090211979 | Ion chromatography system with eluent recycle - Ion chromatography apparatus including (a) a chromatographic column, (b) a source of an aqueous eluent liquid stream, (c) a detector, (d) a recycle line between the detector and the chromatographic column, and (e) a purifying device disposed along the recycle line including ion exchange removal medium. Also, such apparatus with an electrolytic purifying device disposed along the recycle line. Also, methods of using such apparatus. | 08-27-2009 |
20090211980 | ION CHROMATOGRAPHY SYSTEMS WITH FLOW-DELAY ELUENT RECYCLE - 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. | 08-27-2009 |
20090221079 | SAMPLE PRETREATMENT AND EXTRACTION - 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. | 09-03-2009 |
20090277838 | Functionalized substrates with ion-exchange properties - The current invention provides compositions, which are useful as stationary phases for a variety of chromatographic applications, such as high performance liquid chromatography (HPLC) and solid-phase extraction (SPE). The compositions include a porous solid support (e.g., silica gels, silica monoliths or synthetic organic resins) having an exterior surface and pore openings defined by “interior walls”. To the solid support are covalently bound organic ion-exchange ligands (e.g., silyl ligands), which incorporate at least one ion-exchange group (e.g., ionic or ionizable group). The compositions further include micro-particles (e.g., latex particles) incorporating ion-exchange groups having a charge that is opposite to the charge found on the support. The micro-particles are bound to the exterior surface of the support (e.g., via electrostatic forces). The micro-particles have a size that is sufficient to minimize the number of particles that can enter the pores of the support thereby reducing or essentially preventing binding of the micro-particles to the interior walls of the pores. While the pores are essentially too small for the micro-particles, they can still be accessed by the analytes present in a chromatographic sample. The physical separation of ion-exchange groups located within the pores and the surface of the micro-particles, respectively, prevents reactions (e.g., formation of salt-bridges) between the oppositely charged groups and provides compositions with both anion-exchange and cation-exchange capabilities within the same stationary phase. The ligands bound to the solid support can optionally include additional (e.g., reverse-phase) functionalities creating multi-modal (e.g., trimodal) stationary phases. | 11-12-2009 |
20090289009 | Ion chromatography systems with flow-delay eluent recycle - 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. | 11-26-2009 |
20100038245 | Electrochemically Driven Pump - 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. | 02-18-2010 |
20100224012 | FLUID SAMPLE DELIVERY SYSTEM AND METHOD - A fluid delivery system including a filter for filtering solid particles from a liquid sample, the filter including a first filter member configured to filter solid media from a liquid sample, a second filter member fluidly connected to the first filter member, and a third filter member fluidly connected to a downstream end of the second filter member. The second filter member is configured to filter relatively smaller solid media from the liquid sample than the first filter member, and the third filter member is configured to filter relatively larger solid media from the liquid sample than the second filter member. In various aspects, the system includes a displacement-type plunger needle to draw sample fluid from a vial, a cantilevered carousel for rotatably supporting an array of sample holding vials, and a support for supporting the carousel. Method of using the fluid delivery system are also disclosed. | 09-09-2010 |
20110174063 | MULTICHANNEL ION CHROMATOGRAPHY SYSTEM AND METHOD - An ion chromatography housing for easy insertion and removal of a plurality of component cartridges is disclosed. Various components of the IC system are provided in the separate component cartridges. The IC housing includes a capillary separation column and may be connected to conventional-scale components of an IC system. A plurality of IC housings may be provided in a compartment with one or more separation columns. The columns may be capillary columns or conventional-scale columns. A method of using the ion chromatography system is also disclosed. The IC system may be utilized to perform two-dimensional ion chromatographic separation. | 07-21-2011 |
20110174737 | ION CHROMATOGRAPHY SYSTEMS WITH FLOW-DELAY ELUENT RECYCLE - 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. | 07-21-2011 |
20110192722 | ELECTROCHEMICAL DETECTION CELL FOR LIQUID CHROMATOGRAPHY SYSTEM - 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. | 08-11-2011 |
20110210055 | HIGH CAPACITY ION CHROMATOGRAPHY STATIONARY PHASES AND METHOD OF FORMING - The present invention provides a new design for high capacity stationary phases for chromatography, for example, ion chromatography. The stationary phases include a first polymer layer in contact with and at least partially coating the substrate of the stationary phase. The first polymer layer serves as a foundation for the attachment, and in various embodiments, the growth and attachment, of a highly hyperbranched polymer structure, typically based on one or more products of condensation polymerization. Multiple components are of use in forming the first polymer layer and the hyperbranched 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. | 09-01-2011 |
20110284465 | FUNCTIONALIZED SUBSTRATES WITH AROMATIC STACKING PROPERTIES - The current invention provides compositions, which are useful as stationary phases for a variety of chromatographic applications, such as high performance liquid chromatography (HPLC) and solid-phase extraction (SPE). The compositions provide both strong aromatic and hydrophobic interactions with components of a sample. Moreover, the invention provides compositions of new silanes, their immobilization on a solid substrate, such as silica, to form new stationary phases. | 11-24-2011 |
20110290726 | HIGH PRESSURE DEGAS ASSEMBLY FOR CHROMATOGRAPHY SYSTEM AND METHOD - 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. | 12-01-2011 |
20120024793 | ION CHROMATOGRAPHY SYSTEM USING CATALYTIC GAS ELIMINATION - 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. | 02-02-2012 |
20120028368 | SAMPLE PRETREATMENT AND EXTRACTION - 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. | 02-02-2012 |
20120138474 | ELECTROCHEMICALLY DRIVEN PUMP - 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. | 06-07-2012 |
20120141328 | CHEMICAL SUPPRESSORS AND METHOD OF USE - 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. | 06-07-2012 |
20120205315 | NANOMETER SIZE CHEMICAL MODIFIED MATERIALS AND USES - 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. | 08-16-2012 |
20120228227 | CAPILLARY ION CHROMATOGRAPHY - 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. | 09-13-2012 |
20120231195 | ELECTROSTATICALLY BOUND HYPERBRANCHED ANION EXCHANGE SURFACE COATING PREPARED VIA CONDENSATION POLYMERIZATION USING DITERTIARY AMINE LINKERS FOR IMPROVED DIVALENT ANION SELECTIVITY - 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. | 09-13-2012 |
20120255910 | ION CHROMATOGRAPHY SYSTEM USING CATALYTIC GAS ELIMINATION - 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. | 10-11-2012 |
20130026099 | ORGANOSILANES AND SUBSTRATE BONDED WITH SAME - 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. | 01-31-2013 |
20130091936 | ELECTROCHEMICAL DETECTION CELL FOR LIQUID CHROMATOGRAPHY SYSTEM - 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. | 04-18-2013 |
20130180922 | CAPILLARY ION CHROMATOGRAPHY - 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. | 07-18-2013 |
20130213225 | HIGH PRESSURE DEGAS ASSEMBLY FOR CHROMATOGRAPHY SYSTEM AND METHOD - 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. | 08-22-2013 |
20130233093 | SORPTION OF WATER FROM A SAMPLE USING A POLYMERIC DRYING AGENT - 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. | 09-12-2013 |
20130256232 | ION CHROMATOGRAPHY SYSTEMS WITH FLOW-DELAY ELUENT RECYCLE - 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. | 10-03-2013 |
20130259750 | ION CHROMATOGRAPHY SYSTEMS WITH FLOW-DELAY ELUENT RECYCLE - 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. | 10-03-2013 |
20130309777 | SURROGATE ADDITION DEVICE AND A METHOD OF ANALYTE CONCENTRATION - A surrogate addition device is described that adds a surrogate compound at a uniform transport rate to a flowing sample stream. The surrogate addition device includes a surrogate reservoir, a flow chamber, and a diffusion barrier. The surrogate reservoir can be configured to contain a surrogate solution where the surrogate solution includes a surrogate compound. The flow chamber includes an inlet port and an outlet port. At least a portion of the diffusion barrier is disposed in between the surrogate reservoir and the flow chamber. The diffusion barrier may include an inner surface that forms a wall of the surrogate reservoir, and an outer surface that forms a wall of the flow chamber. The flow chamber can be configured to receive a flowing sample solution across the outer surface of the diffusion barrier and also to diffuse the surrogate compound from the surrogate reservoir to the flow chamber. | 11-21-2013 |
20130316466 | SAMPLE PRETREATMENT AND EXTRACTION - 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. | 11-28-2013 |
20140069176 | MULTI-COMPONENT ELUENT GENERATING SYSTEM AND METHOD - 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. | 03-13-2014 |
20140069870 | GLYCIDOL FUNCTIONALIZED ANION EXCHANGE STATIONARY PHASES - 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. This modification is useful for columns operated with a hydroxide or carbonate eluent system. | 03-13-2014 |
20140178912 | SEPARATION OF GLYCANS BY MIXED-MODE LIQUID CHROMATOGRAPHY - An exemplary multimodal chromatographic medium of the invention includes one or more strong anion exchange, weak anion exchange, strong cation exchange and/or weak cation exchange binding sites in combination with one or more reverse phase and/or hydrophilic interaction chromatography binding site. In an exemplary embodiment, the sites interact with one or more glycans in a mixture of glycans in a manner that allows separation of glycans in the mixture and analysis of the glycan mixture. The media are incorporated into devices and systems for chromatographic analysis. Also provided are methods of using the multimodal media of the invention to analyze glycans. | 06-26-2014 |
20140179008 | BUFFER KIT AND METHOD OF GENERATING A LINEAR pH GRADIENT - A buffer kit includes a first eluent and second eluent. The first eluent solution includes at least four buffer salts where at least three of the four buffer salts are a monovalent buffer salt, have a net negative charge or a net neutral zwitterionic charge, and include a sulfonate group and an amine. The second eluent solution includes at least four buffer salts where at least three of the four buffer salts are a monovalent buffer salt, have a net negative charge or a net neutral zwitterionic charge, and include a sulfonate group and an amine. The first eluent solution has a first pH and the second eluent solution has a second pH where the first pH and second pH are different values. The buffer kit provides a linear pH gradient that forms an approximately straight line from at least the first pH to the second pH. | 06-26-2014 |
20140260509 | METHOD OF CALIBRATING A CHROMATOGRAPHY SYSTEM - A method of calibrating, a chromatography system is described. The method includes injecting a standard into a chromatographic separator. The standard including a first analyte having a first calibrant concentration and a second analyte having a second calibrant concentration. The standard can be separated in the chromatographic separator and measured with a detector. The method automatically identifies whether the first peak corresponds to the first analyte or the second analyte and whether the second peak corresponds to the first analyte or the second analyte, based on either an area or a peak height of the first peak and the second peak, and a ratio based on the first calibrant concentration and the second calibrant concentration. | 09-18-2014 |
20140260563 | EPOXY CHEMISTRY DERIVED MATERIALS AS REVERSED-PHASE AND HYDROPHOBIC INTERACTION CHROMATOGRAPHY MEDIA, METHOD FOR THEIR SYNTHESIS AND USE - This invention provides aqueous-compatible, polar-embedded reversed-phase stationary phase compositions, devices and systems comprising the stationary phases as well as methods of producing these compositions using epoxide ring-opening reactions. Also provided are methods of using the stationary phases of the invention in separations. | 09-18-2014 |
20140273264 | EPOXY CHEMISTRY DERIVED MATERIALS AS MIXED MODE CHROMATOGRAPHY MEDIA, METHOD FOR THEIR SYNTHESIS AND USE - This invention provides mixed-mode stationary phase compositions, devices and systems comprising the stationary phases as well as methods of producing these compositions using epoxide ring-opening reactions. Also provided are methods of using the stationary phases of the invention in separations. | 09-18-2014 |
20140332387 | CURRENT EFFICIENT ELECTROLYTIC DEVICE AND METHOD - 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. | 11-13-2014 |
20140370614 | HILIC / ANION-EXCHANGE / CATION-EXCHANGE MULTIMODAL MEDIA - The present invention provides an agglomerated multimodal chromatographic medium. the medium of the invention includes groups active in anion exchange, cation exchange and hydrophilic interaction chromatographic modalities. The invention provides methods of making these media and using them in separations of analytes. Also provided are separations devices incorporating the medium and systems incorporating these separations devices. | 12-18-2014 |