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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

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.

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.

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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: The invention refers to a method and a communication system for transmitting in either direction data between any two devices in a client layer and/or a transport layer of a communication system. The data transmission is performed according to the transport control protocol, referred to hereinafter as TCP. In order to achieve a high data transmission rate it is suggested that central storage means (12) for buffering the data to be transmitted and a TCP protocol operation block (10) are provided within the communication system, wherein the TCP protocol operation block (10) handles references on the transported data stored in the storage means (12) instead of the data itself. The invention also refers to an embedded acquisition device (1) located between the two devices of the communication system, between which the data is to be transmitted. The acquisition device (1) comprises means adapted for performing the method according to the present invention.

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.

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.

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.

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.

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.

Abstract: 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.

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.

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.

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.