Abstract: The present invention relates to a method for improving the efficiency of high-pressure liquid chromatography columns in HPLC. More specifically, the method of the present invention provides a high-pressure liquid chromatography column being divided into a multitude of shorter separation segments, the shorter separation segments being serially connected with cooling segments. By applying an active controlled cooling action on the fluid flow passing through the cooling segments the separation efficiency of the high-pressure liquid chromatography column can be increased significantly.

Abstract: Apparatus and method for detecting current or potential generated in a liquid sample suitable for use in a chromatography or other liquid sample analytical system. One embodiment is an electrolytic ion transfer device with a signal detector in communication with the electrodes of the transfer device. Another is a combination ion transfer device/electrolyte generator. Another substitutes a detector for the ion transfer device in the combination.

Abstract: The invention provided is a split-free nano-liter flow liquid chromatography system comprising at least a first and a second chromatographic column connected in series, wherein an autosampler is provided and programmed to inject samples and eluent solutions of increasing eluent concentration for gradually eluting analytes from the first column into the second column (without adversely affecting separation in the second column), said solutions segmented from the mobile phase of the liquid chromatography system by air plugs.

Abstract: There is provided a method for thermally focusing the elution times of compounds of a liquid chromatography system comprising a pre-column and a separation column as well as to provide a liquid chromatography system, wherein the chromatographic separation of a mixture of substances is optimized.

Abstract: A tight-spot fitting includes an elongated body configured to be inserted into and extracted from an aperture of a device, a user-operable head configured to be manipulated by a user to rotate the elongated body with respect to the aperture of the device, a depression in the user-operable head dimensioned and configured to receive a corresponding driver, and a through-bore extending through the elongated body and the user-operable head into the depression. The through-bore is configured and dimensioned to receive a line therethrough such that when the elongated body portion is inserted into the aperture, the line spans the aperture and through-bore, and extends through the depression.

Abstract: Embodiments in accordance with the present invention relate to packed-column nano-liquid chromatography (nano-LC) systems integrated on-chip, and methods for producing and using same. The microfabricated chip includes a column, flits/filters, an injector, and a detector, fabricated in a process compatible with those conventionally utilized to form integrated circuits. The column can be packed with supports for various different stationary phases to allow performance of different forms of nano-LC, including but not limited to reversed-phase, normal-phase, adsorption, size-exclusion, affinity, and ion chromatography. A cross-channel injector injects a nanolitre/picolitre-volume sample plug at the column inlet. An electrochemical/conductivity sensor integrated at the column outlet measures separation signals.

Abstract: A model of evolution of a signal of a chromatographic column is formed, then inversed as a function of the measured signals, to calculate solute concentrations by using the entire signal. The model is based on equations that govern the transport of solutes in the column as a function of various physical parameters, which can be re-evaluated. The method can be used for searching and measuring rare components, such as proteins, in liquid biological samples.

Abstract: The invention relates to a miniaturized gas chromatograph and injector for the same. Said micro-GC is compact and simple and economical to construct. Dead volumes are largely avoided in order to achieve reliable and reproducible measured results. Said miniaturized gas chromatograph comprises at least one injector, one separation column and a detector which are combined on a circuit board to give a gas chromatography module. The injector comprises a first sheet with channels, which is provided with a second sheet with channels and which may be displaced relative to the latter, whereby at least one of the sheets is provided with a layer of plastic, in particular a chemically inert plastic on the side of the sheet facing the other side.

Abstract: A separation column and a liquid chromatograph using the separation column, which are capable of carrying out a high-speed analysis under high pressure and without a reduction in separation performance of the separation column. In the separation column, a sample and a mobile phase are introduced into a packing material. The chromatograph has a covering member for covering an outer surface of the packing material and a supporting member having the packing material covered with the covering member inserted therein, wherein the level of pressure generated within a gap located between the covering member and the supporting member on the outflow side of the gap, where the fluid-flows out of the gap, is lower than that of pressure generated within the gap on the inflow side of the gap, where the fluid is introduced.

Abstract: The invention relates to a method for separating fractions of a mixture to be separated comprising the steps of providing a device comprising at least two chromatography columns mounted in series, discontinuously injecting a mixture to be separated, in a single point of the device, discontinuously drawing off the fraction enriched in the product of interest, in a single point of the device, injecting eluents in each column and displacing the points for injecting eluents, the eluents having a different eluting power. The method allows efficient separation which is simple to perform.

Abstract: A high performance liquid chromatography method to routinely and reproducibly detect and quantitate metal complexes is provided. The metal complexes used in the method of the invention can be different metal complexes, or they can be stereoisomers of the same metal complexes. The high performance liquid chromatography method of the present invention is suitable for the separation of diastereomers of the same metal complexes. Also provided is a chiral high performance liquid chromatography method to separate enantiomers of metal complexes. Superoxide dismutase mimetic compounds are also provided.

Abstract: After a target compound is captured by an adsorbent within a trap column (7) held by a column rack (8) in a substantially vertical position and the column is filled with water to wash its inside, dichloromethane is slowly introduced from an inlet end (7a) on the lower side by a pump (5). The water within the trap column (7) is pushed upward by dichloromethane and exits from an outlet end (7b), to be disposed of via a two-way selector valve (12) and a disposal passage (14). Dichloromethane elutes the captured target compound. Therefore, when the eluate, which initially consists of water, changes via an emulsion to dichloromethane, the eluate contains an adequately high concentration of target compound. At this point, the two-way valve (12) is switched to a preparative separation passage (13). As a result, a solution that is adequately free from water and yet contains the target compound can be collected into a collection container (17), and the target compound in solid forms can be quickly obtained.

Abstract: An acid or base is generated in an aqueous solution by the steps of: (a) providing a source of first ions adjacent an aqueous liquid in a first acid or base generation zone, separated by a first barrier (e.g., anion exchange membrane) substantially preventing liquid flow and transporting ions only of the same charge as said first ions, (b) providing a source of second ions of opposite charge adjacent an aqueous liquid in a second acid or base generation zone, separated by a second barrier transporting ions only of the same charge as the second ions, and (c) transporting ions across the first barrier by applying an electrical potential through said first and second zones to generate an acid-containing aqueous solution in one of said first or second zones and a base-containing aqueous solution in the other one which may be combined to form a salt. Also, electrolytic apparatus for performing the above method.

Abstract: Methods and systems for evaluating and/or monitoring chromatography column performance are provided. Embodiments apply multivariate analysis (MVA) methods to process data as well as transition analysis data to provide a comprehensive evaluation of chromatography column performance. In embodiments, transition analysis data generated over extended periods of time can be analyzed together with process data to evaluate column performance. Further, embodiments enable a compact and robust tool for combining and presenting performance evaluation results, which allows for time-efficient performance examination.

Abstract: The disclosure features methods of analyzing preparations of heparin, and materials derived from heparin using strong anion exchange high performance liquid chromatography (SAX-HPLC).

Abstract: A temperature control unit (216) for a column (201) of a fluidic device (200) for analyzing a fluidic sample, wherein the fluidic device (200) is adapted to conduct the fluidic sample through the column (201), the temperature control unit (216) being arranged to adjust a temperature of the fluidic sample in a flow path between an inlet 5 (207) of the column (201) and an outlet (208) of the column (201) so that a temperature adjustment effect occurs selectively in an interior of the column (201).

Abstract: Systems and methods for performing chromatography separations or analyses are disclosed. The methods are based upon an equilibrium gradient focusing mode in contrast to conventional transient migration-based modes. By matching the migration speed of one or more analyte(s) of interest to the wave speed of a thermal gradient induced to travel along a region in which chromatographic partitioning occurs, significant improvements in detection limits are achieved. In particular, a temperature gradient focusing strategy is described in which analyte(s) of interest are circulated around a continuous chromatography system in order to focus the analyte(s). Also described are various devices and systems that can be used in the methods described herein.

Abstract: A chromatography detector 11 includes a base substrate having a main surface 12a and a column flow path 15 formed on the main surface 12a, and a substrate block 13 and 14, which has a detection space 18 communicating with an outlet of the column flow path 15 and is stacked on the main surface 12a of the base substrate 12 so as to close a top surface of the column flow path 15.

Abstract: The invention provides methods of improving packed bed chromatography performance.

Abstract: An HPLC column holding apparatus used to mount an HPLC column in one of a plurality of positions is disclosed herein. The apparatus comprises a clip-device interface that secures the apparatus to a platform and a clip-column interface that secures the HPLC column to the apparatus.

Abstract: Advanced remote self-contained chromatographic systems and techniques for analyzing a mixture comprising components having a wide range of boiling points. The chromatographic systems and techniques can utilize components and techniques that allow staged, simultaneous, and/or sequential vaporization of an analyte to facilitate rapid analysis. The chromatographic systems and techniques can also utilize components and techniques that focus eluents from a first separation stage prior to reduce characterization time in subsequent stages.

Abstract: The invention provided is a split-free nano-liter flow liquid chromatography system comprising at least a first and a second chromatographic column connected in series, wherein an autosampler is provided and programmed to inject samples and eluent solutions of increasing eluent concentration for gradually eluting analytes from the first column into the second column (without adversely affecting separation in the second column), said solutions segmented from the mobile phase of the liquid chromatography system by air plugs.

Abstract: The purpose of the present invention is to provide a method which makes it possible to analyze more easily the concentration of glue in an electrolyte solution, while surpressing the degradation of glue during the analysis. There is provided a method for analyzing the concentration of glue contained in an electrolyte solution containing the electrolyte components by using high performance liquid chromatography, characterized in that said method comprises a step wherein an electrolyte solution is added into the eluent pH of which has been adjusted equal to or less than 5 by adding acid to an aqueous solution of phosphate of alkaline metal or alkaline earth metal, a step wherein the eluent into which the electrolyte solution has been added is passed through a separation column the exclusion limit molecular weight of which is 4000-6000 for separating the glue and electrolyte components, and a step wherein the separated glue is detected by a detector.

Abstract: We describe a method for the detection of triacylglycerols (TAGs) in a biological sample.

Abstract: A method for determining the concentration of a chromatographic medium in a liquid slurry comprises the steps of: providing a column (1) having a top end (3) and a bottom end (2) and adapted to retain a chromatographic medium therein; introducing a defined volume of the slurry (15) into the column (1); providing a liquid flow through the column (1) from the top end to the bottom end of the column to settle the chromatographic medium in the column; measuring the bed height of the consolidated chromatographic medium or a value related thereto; and determining from the measured bed height or value related thereto the concentration, or a value related to the concentration of the chromatographic medium in the slurry. A device for performing the method as well as the use of the method in packing of especially large scale columns are also disclosed.

Abstract: A system and method for sample preparation and/or sample enrichment are provided. The system comprises the following components: a first switch element with a switch element input and at least two mutually exclusive switch element outputs and a second corresponding switch element with at least two mutually exclusive switch element inputs and a switch element output, the first and second switch elements being connected to control means for opening and closing the switch element inputs and switch element outputs; a first distributor element with at least three ports and a second distributor element with at least three ports; as well as a first separation column and a second separation column, the components being in such fluidic communication with each other that by means of different positions of the switch elements it is possible to configure at least two different fluidic paths in the system, wherein said different positions are achievable through the control means.

Abstract: The present invention provides a separation column and a liquid chromatograph using the separation column, which are capable of carrying out a high-speed analysis under high pressure and without a reduction in separation performance of the separation column. In the separation column, a sample and a mobile phase are introduced into a packing material. The chromatograph has a covering member for covering an outer surface of the packing material and a supporting member having the packing material covered with the covering member inserted therein, wherein the level of pressure generated within a gap located between the covering member and the supporting member on the outflow side of the gap, where the fluid is introduced, is lower than that of pressure generated within the gap on the inflow side of the gap, where the fluid flows out of the gap.

Abstract: An acid or base is generated in an aqueous solution by the steps of: (a) providing a source of first ions adjacent an aqueous liquid in a first acid or base generation zone, separated by a first barrier (e.g., anion exchange membrane) substantially preventing liquid flow and transporting ions only of the same charge as said first ions, (b) providing a source of second ions of opposite charge adjacent an aqueous liquid in a second acid or base generation zone, separated by a second barrier transporting ions only of the same charge as the second ions, and (c) transporting ions across the first barrier by applying an electrical potential through said first and second zones to generate an acid-containing aqueous solution in one of said first or second zones and a base-containing aqueous solution in the other one which may be combined to form a salt. Also, electrolytic apparatus for performing the above method.

Abstract: The invention provides a method for performing off-line multi-dimensional separation and analysis of a heterogeneous biomolecular sample. The method includes separating the heterogeneous biomolecular sample into a plurality of fractions using an, at least partially, capillary isotachophoresis mechanism. The plurality of fractions are then transferred to a liquid chromatography apparatus where they are each separated into a plurality of sub-fractions. The sub-fractions are then analyzed to determine their constituent molecules.

Abstract: The present invention relates to a column for performing analytical temperature rising elution fractionation (ATREF) characterized in that the packing of said column comprises elastic wires having a good elasticity and a good thermal conductivity. The present invention also relates to a device comprising the column according to the invention, a temperature controlling system for controlling the temperature of said column, a sample injector for injecting a polymer sample solution into said column, a pump for eluting the polymer fractions from said column and a detector for detecting eluting fractions of said sample solution. The present invention further relates to a method for performing ATREF analyses using the column according to the invention.

Abstract: The invention provides a method and apparatus for trapping, releasing and/or separating sample components in solution passing through a channel with or without packing material present by passing ion current through the channel driven by an electric field. A portion of the ion current comprises cation and/or anion species generated from second solution flows separated from the sample solution flow path by semipermeable membranes. Cation and/or Anion ion species generated in the second solution flow regions are transferred into the sample solution flow path through ion selective semipermeable membranes. Ion current moving along the sample solution flow path is controlled by varying the composition of the second solutions and/or changing the voltage between membrane sections for a given sample solution composition. The sample composition may also be varied separately or in parallel to enhance trapping, release and/or separation efficiency and range.

Abstract: The first subject of this invention is a column packing material comprising: a silica gel having a silanol group; a first chemical modification group which is bound to said silanol group; a silicone polymer for coating the surface of said silica gel; and, a trimethylsilyl group which is bound to the silanol group on said silicone polymer and/or the silanol group on said silica gel.

Abstract: A device adapted to hold and compress a granular medium is disclosed. The device includes a body having an opening. A channel is positioned in fluid communication with the opening. A flexible substrate is attached to the body overlying the channel. The substrate and the channel cooperate to form a conduit in fluid communication with the opening. A compression member is mounted on the body. The compression member is engageable with the substrate. Engagement of the substrate by the compression member compresses the granular medium within the conduit. A plug blocks the opening and retains the granular medium within the conduit.

Abstract: A system for automatically performing liquid chromatography analysis of low volume liquid chemical samples at nanosecond flow rates using an analysis column that integrates a pre-concentration trapping column and a chromatography separation column terminating at an electrospray nozzle of an online mass spectrometer. The analysis column consists of a capillary having an inside diameter of between 75 and 125 microns packed throughout with a porous bed of micron particles. A branch outlet positioned 10 to 16 centimeters upstream from the nozzle divides the analysis column into an upstream pre-concentration trap and a downstream separation column. An autosampler delivers low volume liquid samples to the upstream inlet via a two-position valve. Feed connections couple the autosampler to upstream inlet when the valve is open to inject a liquid sample into the pre-concentration trap at a maximum loading flow rate in the range from 0.5 to 50 microliters/minute.

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.

Abstract: The invention relates to a chromatography column for high-pressure liquid chromatography, which can be provided with different connection systems, such as a cartridge retaining device or a reducing screw. The column tube (1, 11) of the inventive chromatography column has an external thread (4,18) at each end and at least one groove (3,14).

Abstract: The present invention is directed to an improved column for use in solid phase synthesis or purification. In a specific embodiment, the column is a disposable plastic column for use in solid phase synthesis or purification of complex chemicals, such as biomolecules and more specifically oligonucleotides. In some embodiments, the column has a top orifice with a sufficient diameter so that a fluid line or a multiple fluid line bundle may dispense fluids into the column with great efficiency. The column has an upper cavity portion configured and sized to render it compatible with dispensing pippetors, so that it can be used as a pipette tip or a pipettor can be used to aspirate the column. The column has a lower cavity portion with a shoulder for ready placement of a lower frit to contain the solid support in a central cavity portion of the column. An upper frit can be conveniently placed in the central cavity portion to seal the solid phase resin.

Abstract: The present invention comprises a device and method of analyzing trace amounts of perchlorate in liquid samples comprising a concentrator column used in an ion chromatographic system that comprises an anionic capacity ranging from about 0.030 microequivalents per column to about 0.060 microequivalents per column and capable of removing substantially all perchlorate from the sample and using a multi-directional flow through said concentrator column in order to enhance perchlorate detection. The invention also comprises a packing material comprising from about 25 percent to about 80 percent of a low anionic capacity material comprising an anionic capacity of less than about 0.03 milliequivalents per milliliter mixed with from about 25 percent to about 80 percent of a high anionic capacity material comprising a anionic capacity of more than about 0.07 milliequivalents per milliliter.

Abstract: Permeable polymeric monolithic materials are prepared in a column casing. In one embodiment, the permeable polymeric monolithic materials are polymerized while pressure is applied through a piston having a smooth piston head in contact with the polymerization mixture. The pressure eliminates wall effect and changes the structure in the column. Similarly, some columns that have a tendency to swell in the presence of aqueous solutions and pressurized while the solution is applied to prevent swelling and wall effect. This procedure also changes the structure in the column. The size of the separation effective openings can be controlled by the amount of the pressure and pores eliminated. Uniformity in the direction flow is improved by controlling polymerization with radiation rather than with conducted heat.

Abstract: The invention relates to a chromatography column for high-pressure liquid chromatography, which can be provided with different connection systems, such as a cartridge retaining device or a reducing screw. The column tube (1, 11) of the inventive chromatography column has an external thread (4,18) at each end and at least one groove (3,14).

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.

Abstract: A method and apparatus for efficiently analyzing an organic macromolecular component contained in a sample with high precision are provided. The method and apparatus for analyzing the organic macromolecular component are based on a flow analysis method with a measuring system including a sample introducing section, a preparing section, and a measuring section, composed of steps of supplying a sample with a carrier solution into the measurement system through the introducing section, leading the sample to the preparing section and separating an organic macromolecular component in the sample, and leading the separated organic macromolecular component to the measuring section and analyzing. Herein, the step of separating the organic macromolecular component includes steps of the organic macromolecular component in the sample being adsorbed on a resin and introducing an eluant into the preparing section and eluting the organic macromolecular component adsorbed on the resin.

Abstract: The present invention provides an on-chip packed reactor bed design that allows for an effective exchange of packing materials such as beads at a miniaturized level. The present invention extends the function of microfluidic analysis systems to new applications including on-chip solid phase extraction (SPE) and on-chip capillary electrochromatography (CEC). The design can be further extended to include integrated packed bed immuno- or enzyme reactors.

Abstract: A probe (1) for quantitatively measuring volatile components of a liquid (2) includes a measurement gas space (3) separated from the liquid (4) by a permeation membrane (5). The membrane (5) is permeable for the volatile component, however nonpermeable for liquid. A selective gas detection system is arranged in the measurement gas space (3) for a defined volatile component. The gas detection system has an IR light source (6), an IR filter (7), (7′) and an IR-sensitive light sensor (8), (8′). Light falls through the IR filter on the light sensor (8), (8′). The IR filter (7), (7′) comprises a transmission window in the range of an alcohol-specific absorption band.

Abstract: An apparatus and method for electrochemically modifying the retention of a species on a chromatography material is disclosed. The apparatus comprises a housing having an effluent flow channel adapted to permit fluid flow therethrough. The effluent flow channel comprises chromatography material. The apparatus further comprises first and second electrodes positioned such that at least a portion of the chromatography material is disposed between the first and second electrodes, and fluid flow through the apparatus is between, and in contact with, the first and second electrodes.

Abstract: A closed &Dgr;Pstat-installation is disclosed for the potential-independent control of the pressure difference for continuous column tests under high hydrostatic pressure, as well as a pressure difference control process useful in particular for carrying out migration tests in pressure columns. By coupling two potential bottles into a closed vessel system, the gas or fluid pressure required to carry out the continuous column tests can be regulated at any desired height independently of outer influences. The pressure difference required to move the liquid is adjusted by setting the potential bottles at predeterminable heights.

Abstract: A sample pre-separation and concentration system for detecting low levels of analytes in highly complex mixtures includes a plurality of trapping columns having a high selectivity for classes of compounds of interest, upstream of a standard separation column. The system may be used, for example, to measure urinary 8 hydroxy 2′ deoxyguanoisine.

Abstract: The present invention generally relates to a microcolumn capable of separating an analyte from a sample in the millisecond time domain. The microcolumn is capable of such rapid separation by employing small column volumes that can tolerate medium to high flow rates. The invention also relates to a method of loading a microcolumn capable of separating an analyte from a sample in the millisecond time domain.

Abstract: Methods and apparatus are disclosed which are useful for detecting the presence of various pesticides, including aryl pyrazoles such as fipronil. Pesticide residues are extracted from a variety of samples, including soil and/or water samples using techniques well known to those of skill in the art. The samples are then concentrated, and transferred to an solid phase extraction cartridge. The SPE cartridge includes activated charcoal, silica gel, magnesium-silica gel and an amino-functional silica sorbent, or suitable equivalents thereof. After cleanup, the eluate containing the analyte of interest can be concentrated to a standard sample size and the amount of pesticide residues quantitated. In a preferred embodiment, the column chromatography materials are assembled in a solid phase extraction cartridge with frits between the chromatography materials. This facilitates the use of the cartridge in standard automated analytical equipment, for example, robotic equipment.

Abstract: Laminates having microfluidic structures disposed between sheets of the laminate are provided. The microfluidic structures are raised on a sheet of laminate, typically by printing the structure on the sheet. Printing methods include Serigraph, ink-jet, intaligo, offset printing and thermal laser printing.