Abstract: A method and apparatus for monitoring and controlling nano-scale flow rate of fluid in the operating flow path of a HPLC system provide fluid flow without relying on complex calibration routines to compensate for solvent composition gradients typically used in HPLC. The apparatus and method are used to correct the flow output of a typical, analytical-scale (0.1-5 mL/min) HPLC pump to enable accurate and precise flow delivery at capillary (<0.1 mL/min) and nano-scale (<1 ?L/min) HPLC flow rates.

Abstract: A drive mechanism for back pressure regulator used in liquid chromatography, supercritical fluid chromatography, or supercritical fluid extraction allows very fine automated control over a very wide range of pressures by combining a linear actuator compressing a spring, pushing a pin. The nozzle assembly of the regulator comprises a flow through chamber containing a diaphragm and a seat, in which the pin pushes the diaphragm against the seat, together with an upstream pressure sensor and electronic feedback control to the motor of the actuator. The BPR of the embodiments exhibits high pressure stability and extremely low pressure noise, even at moderate to high pressures. The exemplary BPR can be use at either constant pressure or to generate pressure programs where the pressure is varied versus time. Further, the nozzle assembly has a field-replaceable head, requiring no mechanical adjustment on replacement.

Abstract: 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.

Abstract: A shear valve, for use in a high performance liquid chromatography system, comprises a first shear valve member and a second shear valve member. At least one of the first and second shear valve members is adapted to be moved with respect to the other. One of the first and second shear valve members comprises a plurality of ports, and the other comprises at least one fluid path for fluidly coupling respective ones of the ports in dependency on a relative movement position of the first and second shear valve members with respect to each other. The first shear valve member is at least partially coated with or comprised of silicon carbide.

Abstract: The invention relates to a monolithic porous material made of amorphous silica or activated alumina, comprising substantially rectilinear capillary channels that are parallel to one another, wherein: the channels have a substantially uniform cross-section relative to each other, the cross-section of each channel is regular over its entire length, the channels pass through the material from end to end, the length of the channels is equal to or more than 10 mm. The invention also relates to an annular, radial or axial chromatographic apparatus, the packing of which consists of at least one said monolithic material. The invention also relates to processes for manufacturing such a monolithic material.

Abstract: Disclosed herein is a chromatography system wherein a sensor, for example, a UV sensor, is tied to a continuously variable load pump in a feedback control loop, with an option to divert the feed stream back to the load vessel or reservoir or onto a second chromatography column, the disclosed chromatography system allowing a true feedback control across variable load rates, thereby adjusting chromatographic operating parameters, for example, variable load rates, to process conditions, while maximizing throughput.

Abstract: 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).

Abstract: A liquid chromatography apparatus is provided with a sample preparation unit, a column that separates components of a sample, an eluent supplier that includes a feeder for supplying eluents to the column, a flow path directional valve capable of introducing fixed amounts of the sample and the eluents to the column, an analyzer for analyzing a test solution composed of the sample components separated by the column and one of the eluents, and a controller, wherein the eluent supplier supplies the eluents to the flow path directional valve in an unmixed state. As a result of employing this configuration, analysis time is shortened and eluent consumption is reduced.

Abstract: An organo-modified silica based material to be used for making a stationary phase for liquid chromatography comprising a part which is unmodified silica, and a part which is silica comprising organic groups bonded to the silica. A method for preparing an organo-modified silica based material comprising mixing in an aqueous medium a silica based material and an organosilane compound, and reacting the mixture. A stationary phase separation material prepared by functionalizing the organo-modified silica based material is also disclosed.

Abstract: A chromatography column having a longitudinal axis and comprising a column wall with a first end and a second end, a first end plate assembly removably connectable to said first end of the column wall, a second end plate assembly removably connectable to said second end of the column wall, wherein said first end plate assembly, said column wall and said second end plate assembly are arranged along the longitudinal axis of the column wherein the column wall, and/or first end plate assembly and/or second end plate assembly is/are rotatable about an axis of rotation wherein said axis of rotation is parallel to the longitudinal axis of said column and positioned outside the column.

Abstract: The chromatographic separation material is a cyclofructan or a derivative of cyclofructan covalently bonded to a cross-linked, organic polymer. The separation material works well in hydrophilic interaction liquid chromatography.

Abstract: The invention relates to a process for the preparation of a separating material having improved binding capacity, and to materials prepared and to the use thereof for the separation of charged or uncharged biopolymers from liquids.

Abstract: There is provided an integrated system for liquid separation, such as LC, CE, affinity chromatography, and ion exchange chromatography, comprising a column and end-fittings embedded in a plastic material, such as a thermoplastic polymer. The system may further comprise an electrospray emitter directly connected with the outlet of the column, wherein a substantial part of the emitter is covered with the polymer material. There is also provided a method by which a separation column along with the accompanying end fittings for connection with adjacent liquid conduits is embedded in a polymer matrix. This configuration e.g. ensures that the factory-made, correct attachment of the fittings to the column is preserved (since the matrix prevents further user intervention, accidental or otherwise). Accordingly, the responsibility for the correct attachment of the fittings is shifted from the end user to the manufacturer.

Abstract: A porous substrate capable of adsorptive filtration of a fluid having a porous self-supporting substrate and one or more porous, adsorptive polymeric coatings comprising from about 1 to about 80% of the void volume of the pores of the substrate. The resultant substrate has good convective and diffusive flow and capacity. The substrate may be cross-linked, have one or more capture chemistries attached to it and is useful as a chromatography media for the selective filtration of desired species including biomolecules such as proteins and DNA fragments.

Abstract: A valve for use in high-performance liquid chromatography has a spherical seat and a ball that, when it abuts against the seat, constrains a fluid from flowing through the valve and is capable of moving axially in order to allow the fluid to flow through the valve. The spherical seat has beveled outer faces in order that a force acting on the valve along the axial direction will generate a force acting on the ball. The inclination of the beveled outer face is such that a force acting on the ball counteracts a force exerted on the spherical seat by the ball and essentially compensates it.

Abstract: A fluid distributor for uniformly distributing flow of a feed onto a chromatography column in a cost-effective way defines a distribution channel of generally conical shape between a solid back plate and a packed bed in the column, wherein the fluid distributor comprises at least two circular and/or annular fluid-permeable porous disks essentially filling the volume of the distribution channel.

Abstract: A chromatography column that captures components in a process liquid in a free flow state and allows elution in steps is described.

Abstract: A liquid chromatography agglomerated bed comprising component A comprising (a) substrate particles and polymer chains (e.g. a condensation polymer) bound to the substrate particles and projecting therefrom, and (b) component B comprising substrate particles having external surfaces of opposite charge to that of the charged polymer chains, components A and B being bound at least in part by electrostatic forces between the component A charged polymer chains and the component B external surfaces to form in composite an agglomerated bed of ion exchange particles packed in a chromatography column.

Abstract: Presteralized manifolds are provided which are designed for sterile packaging and single-use approaches. Disposable tubing and flexible-wall containers are assembled via aseptic connectors. These manifolds interact with valves and pumping equipment which can be operated by a controller which provides automated and accurate delivery of biotechnology fluid. The manifold also being used in conjunction with one or more conductivity sensors used to measure the conductivity of the biotechnology fluid. Such sensors interact with the controller or are connected to a separate user interface. The combination of disposable tubing, flexible-wall containers, aseptic connectors, manifold, controller, and conductivity sensors provides an aseptic environment while avoiding or reducing cleaning and quality assurance procedures.

Abstract: Modified diamond particles for use in chromatography with a desired functional group at the diamond surface, formed from reaction of hydroxyl groups at diamond surfaces with a reactive molecule.