Abstract: An aerator for immersed filtering membranes has an aerator shell with openings for discharging bubbles from its upper surface and a shape capable of temporarily containing a volume of air in fluid communication with the openings. The shell is open to tank water below it and located so that discharged bubbles will rise through an assembly of the filtering membranes. The shell may be wholly or partially made of parts of the assemblies of filtering membranes. A supply of air is provided to the air space in the aerators alternating between a high flow rate and a low flow rate in short cycles of between about 10 seconds and 100 seconds. A filtration system has an inlet for adding substrate and an outlet for retentate are located so as to create a horizontal flow of substrate through the tank. Membrane assemblies are located within the horizontal flow of substrate. Aerators as described above are provided and operated as described above.

Abstract: A method and device for chromatographic separation producing at least two fractions are provided, in which: (i) the solvent is at least partially evaporated from the fractions produced; (ii) the solvent vapours thus produced are separated; stage (i) of the method being carried out, for at least one of the fractions, at least partially with the separated solvent vapours originating from one of the other evaporated fractions.

Abstract: A reconfigurable multi-mode post-column analysis system improves resolution of liquid chromatography detection data by providing a parking or MS/MS detection mode in which flow of column eluent is substantially reduced to provide greater analysis time within a single eluting detection peak. A micro switching valve unit is reconfigurable between normal (MS) mode that passes column eluent directly to an MS unit, and a peak parking (or MS/MS) mode, in which normal mode column flow is interrupted, and the gradient halted, while more slowly flowing the detection peak of interest through the MS unit. A micro syringe pump contributes to the substantially lower MS/MS flow rate. A MS control unit controls micro switching valve valves to reconfigure between MS and MS/MS modes. After a detection peak, MS mode is reestablished, and the system primary pump returns to normal mode flow rate and gradient conditions. Mode changes can be carried out for each chromatogram detection peak.

Abstract: Methods and apparatus for characterizing a polymer sample and in preferred embodiments, libraries of polymer samples, in a comprehensive, directly-coupled multi-dimensional liquid chromatography system are disclosed. The first and second dimensions are preferably high-performance liquid chromatography dimensions, such as for example, a first dimension adapted for determining composition (e.g. adapted for mobile-phase gradient elution chromatography, including reverse phase chromatography, adsorption chromatography and the like), and a second dimension adapted for determining molecular weight or particle size (e.g., adapted for size exclusion chromatography, including gel permeation chromatography).

Abstract: A method of managing the valves of a simulated moving bed separation system comprising at least one column of adsorbent beds split into several zones delimited by injection and draw-off points, allowing finer monitoring of a determined concentration profile. The method comprises, during each period between the shift times of the injection and draw-off points, in opening and closing a first valve located at one end of a zone according to a determined law, while opening and closing the valve downstream from the first valve in relation to the direction of flow of the recirculation flow, according to the same law with a lag, referred to as overlap time, in relation to the first valve, which is less than or equal to the period, the law imposing a constant total flow rate for the flow passing through the two consecutive valves throughout the overlap time.

Abstract: Systems and methods for collecting the output of multiple simultaneously operated chromatography columns and providing the outputs to a single mass spectrometer are provided. Such systems utilize predetermined lengths of microfluidic tubing that act as storage buffers for the substantially all of the output of each column, preserving all data and, because the storage buffers are microfluidic, there is minimal diffusion between sample bands and solvent and signal clarity is preserved.

Abstract: The present invention relates to a method and apparatus for chromatographically analyzing each of a plurality of samples in detector, comprising an autosampler to contain a plurality of samples for chromatographic analysis and a plurality of chromatographic systems, each system comprising one or more pumps and one or more chromatography columns. A detector is included for detecting compounds in the samples from each of the chromatography systems along with a valve positioned between the detector and the plurality of chromatography systems, the valve permitting each sample to reach the detector in sequence. A computer control device is included which adjusts the introduction of samples from the autosampler into the plurality of chromatography systems as well as the position of the valve to sequentially separate and deliver compounds within the samples to the detector.

Abstract: An apparatus for removing charged contaminants from a water stream. The apparatus can be figured to provide the decontaminated water stream to an analytical system. Methods of use of the same are also disclosed.

Abstract: A continuous simulated moving bed chromatographic focusing process is disclosed for separating and concentrating multiple components from a complex mixture. Said process comprises a number of zones that are connected in series. An eluent flows unidirectionally along the zones and decreases its desorption strength by sequential dilutions zone after zone. Each zone is detachably installed with a chromatographic column and the columns are periodically relocated one zone upstream. Multiple components of a sample are introduced into a downstream zone, absorbed on the column in the zone, brought zone by zone upstream by column relocations, and selectively desorbed from different zones to get separation. A component desorbed from one zone is reabsorbed by the column in the adjacent downstream zone and is again brought back to said zone by column relocation.

Abstract: Liquid chromatography based on the difference of two or more kinds of separation modes, (e.g., chemical or physical properties of analytes) may improve separations when samples contain complex mixtures. In this invention, the analytes separated on the 1st analysis system (consisting of the 1st column and the 1st mobile phase) will be trapped onto individual trapping columns. Then the trapped analytes will be loaded onto the 2nd analysis system consisting of the 2nd column and the 2nd mobile phase. This invention has the trapping and loading mechanism consisting of a combination of switching valves necessary to produce the serial separations. Also this invention has the capability to affect online desalting when it is needed depending on a detector or the nature of the analyte mixture.

Abstract: A prepartive chromatography system, and a separation and purification method using the system, are provided for small scale, low cost, efficient multicomponent separation and purification without the drawbacks of conventional separation and purification systems. The chromatography system and the separation and purification method using it include three or more column units arranged in parallel, and their outlets, from which fractions are taken out, are connected to the same flow path.

Abstract: A device and process for injecting a diverted fluid into a simulated moving bed comprises a vessel containing beds of adsorbant Ai separated by plates Pi for distributing and extracting fluids, each plate comprising at least one pannel, each pannel comprising a single chamber Ci for distributing, mixing and/or extracting fluid, and a bypass circuit placing a plate in communication with a bypass line (Li, j). The device also comprises means (14, Voi,j, 20) for bringing at least one chamber (Ci) into communication with at least one bypass line (Li, j); one end of the bypass line is connected with said chamber Ci of a pannel of plate Pi and the other end communicates with a region (Ri+1) of a pannel of the distributor plate Pi+1, said region being distinct from the distribution chamber Ci+1. Application to separating n-paraffins containing 10 to 13 carbon atoms from sweetened kerosene type feeds.

Abstract: A method and device for increasing the loading capacity of a chromatography column through dilution of a mobile phase at the head of the column. A strong mobile phase is provided for dissolving a sample. A sample is injected into the strong mobile phase, and subsequently diluted with a weak mobile phase. The resulting sample-containing weak mobile phase is passed through a chromatography column for retention and separation of the components of the sample.

Abstract: The present invention provides a device for improving detection sensitivity and a method for improving the detection sensitivity for use in a low flow velocity high performance liquid chromatographic apparatus. That is, the present invention is a diffusion promoting device connected at just before a separation column and having a function for improving detection sensitivity for use in a low flow velocity high performance liquid chromatographic apparatus.

Abstract: Gradient performance with high pressure gradient solvent delivery system is optimized by approximation of infinite stroke volume of high pressure pumps by the addition of pulse dampening with backflow prevention to each high pressure pump. The backflow prevention adds sufficient minimum flow resistance, thereby enhancing the performance of the pulse dampening over a wider range of flow rates resulting in consistent gradient performance.

Abstract: The invention encompasses systems for column-based separations, methods of packing and unpacking columns and methods of separating components of samples. In one aspect, the invention includes a method of packing and unpacking a column chamber, comprising: a) packing a matrix material within a column chamber to form a packed column; and b) after the packing, unpacking the matrix material from the column chamber without moving the column chamber.

Abstract: High-performance liquid chromatography (HPLC) methods and systems are disclosed that combine parallel chromatographic separation of a plurality of samples with a detection technique that involves post-separation treatment of the plurality of samples to enhance one or more properties of the sample or of a component thereof, followed by detection of the one or more enhanced properties. Selective, tunable detection schemes are achievable, and are particularly advantageous as applied in connection with combinatorial chemistry, combinatorial material science and more particularly, combinatorial synthesis and screening of polymeric materials.

Abstract: The invention relates to a method comprising a multistep process for recovering betaine, erythritol, inositol, sucrose, mannitol, glycerol and amino acids from corresponding starting materials. The invention comprises the use of a weakly acid cation exchange resin in chromatographic column in the multistep process. The starting materials are especially beet molasses, betaine molasses, syrups, thick juices, raw juices, corn steep cane based solutions and glycerol.

Abstract: A fraction collection system for liquid chromatography includes a conduit, which directs a sample eluent from an LC column through a flow splitter to a destructive analytical detector such as a mass spectrometer to analyze sample components, and to a fraction collector. A nondestructive detector such as a photodetector is positioned near the fraction collector to detect arrival of sample components. Optionally, a nondestructive detector such as a photodetector is situated upstream from the splitter, to detect passing sample components. Time intervals between detection of a calibrant or a sample component at any two of the detectors provide for automatable identification of selected sample components at the sample collector.

Abstract: A sample separation apparatus including a porous, or rough, capillary column. The porous capillary column includes a matrix which defines pores, and may be formed from a material such as porous silicon. Alternatively, the capillary column may have a rough surface of hemispherical grain silicon. The capillary column is defined in a surface of a substrate, such as silicon. The sample separation apparatus may include a stationary phase or a capture substrate disposed on the surfaces thereof. The sample separation apparatus may also include a detector positioned proximate the capillary column. A variation of the sample separation apparatus includes an electrode proximate each end of the capillary column. The sample separation apparatus may be employed to effect various types of chromatographic separation, electrophoretic separation, and analyte identification.

Abstract: A continuous simulated moving bed chromatographic focusing process is disclosed for separating and concentrating multiple components from a complex mixture. Said process comprises a number of zones that are connected in series. An eluent flows unidirectionally along the zones and decreases its desorption strength by sequential dilutions zone after zone. Each zone is detachably installed with a chromatographic column and the columns are periodically relocated one zone upstream. Multiple components of a sample are introduced into a downstream zone, absorbed on the column in the zone, brought zone by zone upstream by column relocations, and selectively desorbed from different zones to get separation. A component desorbed from one zone is reabsorbed by the column in the adjacent downstream zone and is again brought back to said zone by column relocation.

Abstract: The present invention relates to a method of preparing enantiomers and diastereomers of a 2′,3′-dideoxy-5-fluoro-3′thiocytadine (FTC) or a derivative thereof as represented by the structural formula (I), wherein R is H, a substituted or unsubstituted organic acid radical, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted heteroarakyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted heterocycloalkyl group, a substituted or unsubstitued cycloalkylalkyl group, a substituted or unsubstituted heterocycloalkylalkyl group, a sugar or a protecting group.

Abstract: A high throughput high performance chromatography system operating at a high mixing pressure including a plurality of pressurized solvent reservoirs, e.g. pumps, each maintaining an associated solvent at a substantially constant pressure. A plurality of flow control valves are connected downstream or upstream of the reservoirs for controlling the flow rate of the solvent into the respective columns. The number of reservoirs equals the number of solvents. Accordingly, the system reduces the number of pumps required thereby saving money and space. Furthermore, the system increases sample throughput, accelerates method development and minimizes organic waste.

Abstract: A plating apparatus comprises a plating unit having a plating bath for holding a plating liquid therein, and a planting monitoring unit having a liquid chromatography device and an arithmetical unit. The liquid chromatography device serves to separate and quantify an additive in a sample of the planting liquid. The arithmetical unit serves to compare a quantified value of the additive with a given concentration predetermined for the additive and to produce an output signal representing the compare result. The plating apparatus further comprises an additive replenishing unit for adding a solution including the additive from an additive tank to the plating liquid in the planting bath based on the output signal from the arithmetical unit in the plating liquid monitoring unit.

Abstract: Systems and processes are provided that are useful for separating components from feed streams containing multiple components. Systems and processes of the present invention are based on simulated moving bed technology.

Abstract: The invention relates to methods of separating compounds of interest from mixtures using high performance liquid chromatography (HPLC). An initial separation of a sample of a mixture is performed to predict a retention time and elution time for the compound of interest on a preparative scale HPLC column and, optionally, to verify that an expected compound of interest is present in the mixture. Preparative scale HPLC is then used to separate and collect at least a portion of the compound from the mixture using the predicted elution time of the compound.

Abstract: Methods and apparatus for characterizing a polymer sample and in preferred embodiments, libraries of polymer samples, in a comprehensive, directly-coupled multi-dimensional liquid chromatography system are disclosed. The first and second dimensions are preferably high-performance liquid chromatography dimensions, such as for example, a first dimension adapted for determining composition (e.g. adapted for mobile-phase gradient elution chromatography, including reverse phase chromatography, adsorption chromatography and the like), and a second dimension adapted for determining molecular weight or particle size (e.g., adapted for size exclusion chromatography, including gel permeation chromatography).

Abstract: Methods and apparatus for the evaluation of interactions between substances using inverse chromatography are disclosed. Preferably, interactions are evaluated between a liquid test sample and a solid phase comprising a receptor in the presence of a liquid carrier. Preferably, one of the modifying agent or receptor are members of a combinatorial library.

Abstract: Disclosed are apparatus for screening compound libraries using frontal chromatography in combination with mass spectrometry to identify and rank those members of the library that bind to a target receptor. The apparatus of this invention also permit a compound library to be rapidly screened to determine if any member of the library has an affinity for the target receptor as measured by a pre-selected indicator compound.

Abstract: An access valve suitable for controlling fluid flow into and out of a chromatography column has a central axially movable probe with a head acting as a spool valve in a barrel. Axial movement of the probe adjusts the valve between a fully open condition, in which both a first conduit extending through the probe and a second conduit defined around the probe are open to the column interior, a partly open condition in which a second sealing land on the probe closes the second conduit, and a fully closed position in which both conduits are closed. The three positions are useful for packing and unpacking chromatography media into and from the column. In the closed condition of the valve, the first and second conduits communicate with one another so that the valve interior can be cleaned while the column is operating.

Abstract: An optically active poly(N-&agr;-methylbenzylmaleimide) represented by the following formula (1): wherein n is a number within a range of from 2 to 10,000, and symbol * represents optically active carbon, and having a specific rotation ([&agr;]43525) of at least +30°.

Abstract: A process for separating at least one component of a mixture in a set of closed-loop chromatographic columns is described, whereby the loop comprises at least one feedstock injection point, a raffinate draw-off point, an eluant injection point, and an extract draw-off point, in which a determination is made between an injection point and a draw-off point or vice-versa a chromatographic zone, and at the end of a given period of time, all of the injection points and draw-off points are shifted by the same number of columns or column sections and advantageously by one column or column section in a given direction that is defined relative to that of the flow of a main fluid that circulates through the loop. During the period, the shifting of different injection points and draw-off points of at least one column or column section is done at different times in such a way that the lengths of the zones that are defined by said different points are variable.

Abstract: The invention concerns a method supplying volume streams of fluids in channels or capillaries of small stream cross sections, more particularly chromatographic separating columns for the analytical fluid metrology, wherein a delivery device for delivering a volume stream of the fluid through an operating channel and a pressure measuring device for measuring the pressure in the operating channel is provided, wherein a measurement of the volume stream is possible, characterized by the following steps: a) Recording a time reference pressure course using the pressure measuring device in the operating channel, while the delivery device delivers an essentially constant, pre-determinable reference volume stream through the operating channel of a fluid with properties, more particularly flow properties, varying over time; b) Calculation of a time development of the operating pressure, which corresponds to the essentially constant and preferably small operating volume stream through the operating channel, which is d

Abstract: An integrated suppressor and detector for suppressed ion chromatography includes a stationary phase, a fluid flow path, at least first and second regeneration electrodes, and at least first and second sensor electrodes. Methods of suppressed ion chromatography using the integrated suppressor and detector are also described.

Abstract: Object of the invention is a process for the chromatographic purification of cyclosporin A from a crude product containing cyclosporin complex by using a column filled with silica gel and by the application of multistep chromatography with a column filled with normal phase silica gel and by a solvent mixture containing toluene as the major component.

Abstract: The invention relates to a process for purifying a maltose-containing liquor from a undesired impurities, such as maltotriose. The process of the invention is characterized by nanofiltering said liquor and recovering a purified maltose solution as the permeate.

Abstract: A system for collection of liquid phase sample fractions from a supercritical fluid chromatography system is disclosed. The system has different ways of gathering the liquid phase into a collection chamber and provides for automated removal of liquid phase from a collection chamber into separate collection container. A separate pressure scheme is invoked upon the collection chambers to move liquid phase out of a chamber and into the separate collection container. In addition, the invention provides a renewal system for the collection chambers where each chamber returns to an uncontaminated stated by washing with a cleaning solution after removal of collected liquid phase. Spent cleaner from a chamber is purged using the pressure system into a waste stream for disposal.

Abstract: The invention relates to a method for the fractionation of molasses using a chromatographic simulated moving bed system with two or more loops in which the liquid flow can be effected in a system comprising at least two chromatographic partial packing material beds. In the method of the invention, product(s) are recovered during a process comprising one or more of the following phases: a feeding phase of molasses, an eluting phase and a recycling phase. The liquid present in the partial packing material beds with their dry solids profile can be recycled in the recycling phase in one or more loops comprising one or more partial packing material beds.

Abstract: A continuous annular chromatography (CAC) device is disclosed including a stationary column head, a stationary eluate ring, a rotating body which is located between said column head and said collecting ring and which can rotate about a vertical axis and contains a chromatographic separating medium and a drive device. An extension can be coupled to a drive shaft of the drive device with a rapidly detachable connection.

Abstract: A method for the chromatographic separation of vitamin E isomers such as &agr;-tocopherol, &bgr;-tocopherol, &ggr;-tocopherol, &dgr;-tocopherol, &agr;-tocotrienol, &bgr;-tocotrienol, &ggr;-tocotrienol and &dgr;-tocotrienol from a vitamin E containing mixture by combining the vitamin E mixture with an adsorbent to effect adsorption of the vitamin E isomers on the adsorbent; and then selectively desorbing the vitamin E isomers from the adsorbent with a solvent under supercritical conditions.

Abstract: A fractionated sample collection process and device having at least one pressurized chamber used to gather and store liquid samples generated from a flow stream containing a mixture of highly compressed gas, compressible liquid, or supercritical fluid and a relatively incompressible liquid. A bank of multiple collection chambers is secured together in a frame to form a cassette unit. Each collection chamber may house a replaceable liner such as a test tube vial, to hold a fractionated liquid phase sample. After filling with sample, a collection chamber is returned to a clean state and ready for refilling with a new sample by manually or automatically replacing the liner.

Abstract: A method for separation of enantiomers of a lactam represented by formula (I): where n and m are each, independently, 0, 1, 2, or 3; P is H or an N-protecting group; and the dotted line represents an optional double bond, by liquid chromatographing the mixture on a chiral stationary phase, where said stationary phase is derivitized with at least one sugar derivative, with an eluent which comprises acetonitrile.

Abstract: A process for determining by simulation the optimum stabilization conditions of a simulated moving bed (SMB) separation system allows to obtain set values for the purity of an extracted constituent and for the efficiency. In order to determine the optimum flow rates, a single simulation is carried out, which includes a succession of stages intended for rectification of the fluid flow rates during limited time intervals (T), including each, after each time interval, comparison of the respective purity degrees and efficiencies obtained, resulting from situations stemming from simulations over a time interval (&Dgr;t) where rectifications are applied to at least one flow rate, with those of a reference situation resulting from a simulation over the same time interval but without flow rate rectification, followed by a selection of flow rates aimed to minimize the quantity of impurities in the extract and the quantity of constituent in the raffinate.

Abstract: The invention relates to a method for the fractionation of molasses using a chromatographic simulated moving bed system in which the liquid flow is effected in a single direction in a system comprising at least two chromatographic partial packing material beds. In the method of the invention, the product or products are recovered during a multi-step sequence comprising the following phases: feeding phase of molasses, eluting phase and recycling phase. The liquid present in the partial packing material beds with their dry solids profile is recycled in the recycling phase in a loop comprising one, two or several partial packing material, beds.

Abstract: The invention encompasses systems for column-based separations, methods of packing and unpacking columns and methods of separating components of samples. In one aspect, the invention includes a system for column-based separations, comprising: a) a fluid passageway, the fluid passageway comprising a column chamber and a flow path in fluid communication with the column chamber, the flow path being obstructed by a retaining material permeable to a carrier fluid and impermeable to a column matrix material suspended in the carrier fluid, the flow path extending through the column chamber and through the retaining material, the flow path being configured to form a packed column within the column chamber when a suspension of the fluid and the column matrix material is flowed along the flow path; and b) the fluid passageway extending through a valve intermediate the column chamber and the retaining material.

Abstract: This invention relates to a high efficiency chromatographic system. More specifically, the present invention relates to a chromatographic system for determining the physicochemical properties of one or more compounds using at least two chromatographic units in eluent flow communication with one eluent analyzer via an intermediate eluent switch. The present chromatographic system allows determination of physicochemical properties through the use of multiple chromatographic units in communication with one eluent analyzer via an eluent switch.

Abstract: The present invention relates to a method and apparatus for chromatographically analyzing each of a plurality of samples in detector, comprising an autosampler to contain a plurality of samples for chromatographic analysis and a plurality of chromatographic systems, each system comprising one or more pumps and one or more chromatography columns. A detector is included for detecting compounds in the samples from each of the chromatography systems along with a valve positioned between the detector and the plurality of chromatography systems, the valve permitting each sample to reach the detector in sequence. A computer control device is included which adjusts the introduction of samples from the autosampler into the plurality of chromatography systems as well as the position of the valve to sequentially separate and deliver compounds within the samples to the detector.

Abstract: A method is provided for translating from a first method for performing gas chromatographic analysis to a second method for performing gas chromatographic analysis in a gas chromatography system without changing a peak elution pattern. Unlike the known method translation techniques that work only with the constant pressure gas chromatographic analyses, the invention can translate the gas chromatographic methods where column pressure and/or carrier gas flow rate change during the analysis by an arbitrary program.

Abstract: A process and device for chromatography, such as preparative and analytical supercritical fluid chromatography, or supercritical fluid extraction for a liquid phase SFC collection system that separates and retains eluted components from sample injections. The process efficiently separates liquid and gas phases in the flow stream upstream of a collection vessel and without additional pressure schemes or solvent extractions imposed on the flowstream. Sample fractions are collected from sample component concentration peaks based upon the chromatographic elution of the sample components. Samples are repeatedly the injected into the mobile phase flow stream and collected into large volume collection containers, thereby allowing longer unattended run times and cost-efficient sample purification and recovery.

Abstract: Volume flows of liquids in capillary tubes of chromatographic separation columns for analytical liquid measuring technology are controlled. The volume flows are derived from a liquid transport, i.e., pump arrangement, which transports a total flow to a flow splitter that divides the total flow into an excess flow in an excess path and a working flow in a working path. A controller for the working flow responds to at least one working sensor. The working sensor senses the mass flow rate of the working flow and/or the pressure in the working path which is coupled with the working sensor or the pressure differential in conduits for the excess and working flows.