Abstract: Described is a mobile phase fitting having reduced corrosion and erosion. The fitting includes a coupling body, compression screw, compression member and gasket. The coupling body has a threaded bore at one end, a tapered cavity, a narrow bore and a fluid channel. The compression screw has an axial bore to receive a tube and a threaded outer surface in engagement with the threaded bore of the coupling body. The compression member is disposed in the tapered cavity and has an axial opening to pass the tube and a tapered surface to engage a surface of the tapered cavity. The gasket is disposed in the narrow bore and has one surface in contact with the first internal surface and has a parallel surface to receive an end face of the tube. Mobile phase flows along a path that includes the tube, an opening in the gasket and the fluid channel.

Abstract: A chromatography system has an associated system volume and a sample dispersion volume. The chromatography system comprises a pump pumping a flow of gradient, a sample manager for introducing a sample into the flow of gradient, and a valve manager fluidically coupled to the pump and to the sample manager. The valve manager includes at least one valve. A first valve of the at least one valve has a plurality of ports including an inlet port that receives the flow of gradient from the pump and an outlet port through which the flow of gradient exits the first valve. The first valve has at least two different, automatically selectable positions. A first position of the at least two different automatically selectable positions operating to change one of the system and sample dispersion volumes of the chromatography system when the first valve is automatically switched into the first position.

Abstract: A rotary valve used in chromatography includes a stator with a plurality of stator ports arranged on the stator. The stator further includes a stator groove connected at one end to a first stator port and terminating between the first stator port and a second stator port adjacent to the first stator port. A rotor, rotatably fitted to the stator, has a plurality of arcuate channels arranged in an asymmetrical pattern on the rotor. Each rotor channel connects to one or more of the stator ports. Different connections of the rotor channels to the stator ports produce at least three different positions for the injection valve. The three different positions provide a complete chromatography sample injection sequence using only a single valve.

Abstract: Described are a method and a system for diluting a sample at a location of injection in a liquid chromatography system. The method includes loading a sample into a first fluid channel, separating a flow of a mobile phase into a first flow in the first fluid channel and a second flow in a second fluid channel, and combining the sample that is displaced from the first fluid channel and the mobile phase exiting the second fluid channel at the location of injection into the system flow to thereby generate a diluted sample in the system flow. The dilution ratio of the diluted sample is responsive to the flow rates of the first and second flows. Advantageously, the flow rates can be changed by changing the flow restriction of one of the fluid channels. Thus providing the proper flow restriction enables a user to obtain a desired dilution ratio.

Abstract: Described are a method and a system for injecting a sample into a flow of a liquid chromatography system. The method includes combining a flow of a sample and a flow of a mobile phase to create a diluted sample in the system flow. The volumetric flow rate of the sample is controlled to be at a value that yields a desired dilution ratio for the diluted sample. The particular value at which the volumetric flow rate is maintained can be determined from the desired value of the dilution ratio and the volumetric flow rate of the mobile phase. System embodiments include a syringe that can be used to provide a sample solution at a controllable volumetric flow rate for combination with a high pressure mobile phase.

Abstract: The invention provides compression fittings and methods of assembling compression fittings. In exemplary embodiments, compression fittings are provided that include a fitting body, a ferrule and a tube. For example, the fitting body can be removably coupled to the ferrule when the tube is disposed therethrough.

Abstract: Described are a method and system for diluting a sample in a liquid chromatography system. A sample flowing at a first flow rate is combined for a predetermined time with a diluent flowing at a second flow rate to generate a volume of diluted sample. The diluted sample has a dilution ratio determined according to the two flow rates. A portion of the volume is loaded into a sample loop of an injection valve and subsequently injected into a mobile phase flowing to a chromatography column. The method eliminates the need to have a technician available to perform dilutions or to transfer the sample to a remote location for dilution. Advantageously, manufacturing or processing downtime to perform the dilution is not required and the amount of sample flowing to waste is reduced.

Abstract: The present disclosure relates to phase detection in multi-phase fluids where two fluid phases can be present in the fluid. Phase detection apparatus and methods are disclosed for determining the phase(s) (e.g., supercritical, liquid, and/or gas) of a fluid in a multi-phase fluid system, such as carbon dioxide based separation and chromatography system.

Abstract: A check valve comprises a valve seat element along a fluid path that is formed of a polymeric material and comprises a hole that extends from an input end of the valve seat element to an output end of the valve seat element. The valve seat element includes an inner taper that transitions the input end to the output end, the valve seat element including a sealing surface along the inner taper. A poppet body is formed of a polymeric material and configured to engage the internal tapered sealing surface of the valve seat element. The poppet body moves between a first position at which the poppet body sealingly engages the tapered sealing surface of the valve seat element and a second position at which the poppet body is separate from the inner taper of the valve seat member.

Abstract: A sampling system comprising an external sampling assembly in fluidic communication with a process sample manager is provided herein. The sampling system can automatically acquire sample from one or more sources of sample to prepare sample for injection into a column or detector. The external sampling assembly has an external sampling valve connected to an external pump and is in fluidic communication with a process sample manager. The external sampling valve has a first configuration and a second configuration useful in three steps of drawing, loading and discharging sample. Two selection valves can be connected to a plurality of external sampling valves for sequential sampling of multiple sources of sample. Sample can also be diluted in the process sample manager and then combined in a solvent composition stream for injection into the column or the detector.

Abstract: Process sample and dilution systems automatically draw sample from a reactor or other source of sample and prepare drawn sample for subsequent injection to a chromatographic column or a detector. The process sample and dilution system has an external pump valve assembly in fluidic communication with a process sample manager. The external pump valve assembly includes an external sampling valve, an external process valve, external pump and a mixing tee. The external sampling valve can be configured to automatically acquire sample from a reactor or other source of sample. The external pump discharges wash from the external process valve whereby sample is discharged from the external sampling valve to the mixing tee for quenching and dilution and subsequent processing by the process sample manager.

Abstract: Described are a method and a system for injecting a sample into a flow of a liquid chromatography system. The method includes combining a flow of a sample and a flow of a mobile phase to create a diluted sample in the system flow. The volumetric flow rate of the sample is controlled to be at a value that yields a desired dilution ratio for the diluted sample. The particular value at which the volumetric flow rate is maintained can be determined from the desired value of the dilution ratio and the volumetric flow rate of the mobile phase. System embodiments include a syringe that can be used to provide a sample solution at a controllable volumetric flow rate for combination with a high pressure mobile phase.

Abstract: Described are a method and a system for diluting a sample at a location of injection in a liquid chromatography system. The method includes loading a sample into a first fluid channel, separating a flow of a mobile phase into a first flow in the first fluid channel and a second flow in a second fluid channel, and combining the sample that is displaced from the first fluid channel and the mobile phase exiting the second fluid channel at the location of injection into the system flow to thereby generate a diluted sample in the system flow. The dilution ratio of the diluted sample is responsive to the flow rates of the first and second flows. Advantageously, the flow rates can be changed by changing the flow restriction of one of the fluid channels. Thus providing the proper flow restriction enables a user to obtain a desired dilution ratio.

Abstract: Described is a coupling seal that includes a polymeric body having a bore extending from a first end to an internal sealing surface and a fluid channel extending from the internal sealing surface to a second end. The bore is configured to receive a tube having a fluid channel so that an endface of the tube engages the internal sealing surface. The second end of the polymeric body is configured to contact a sealing surface of a coupling body that has a fluid channel extending from the sealing surface. A fluidic seal occurs when the coupling seal is compressed between the endface and the sealing surface. A void between an outer surface of the polymeric body and an inner surface of the coupling body receives the deformation of the coupling seal while under compression to thereby prevent the fluid channel of the tube from being crushed or obstructed.

Abstract: Described is a rotary valve including a stator element and a rotor element. The stator element defines a first inlet passage, a second inlet passage, and a first outlet passage, respectively, having a first inlet port, second inlet port and first outlet port in a stator face. The rotor element has a rotor face in contact with the stator face and has a first channel and a second channel formed therein. The rotor element is rotatably movable about a rotational axis to at least a first position and a second position. In the first position, the first inlet port is fluidly coupled to the first outlet passage by the first channel and the second inlet port is fluidly coupled to the first outlet passage by the second channel. In the second position, the first inlet port is fluidly coupled to the first outlet passage by the first and second channels.

Abstract: Described is a mobile phase fitting having reduced corrosion and erosion. The fitting includes a coupling body, compression screw, compression member and gasket. The coupling body has a threaded bore at one end, a tapered cavity, a narrow bore and a fluid channel. The compression screw has an axial bore to receive a tube and a threaded outer surface in engagement with the threaded bore of the coupling body. The compression member is disposed in the tapered cavity and has an axial opening to pass the tube and a tapered surface to engage a surface of the tapered cavity. The gasket is disposed in the narrow bore and has one surface in contact with the first internal surface and has a parallel surface to receive an end face of the tube. Mobile phase flows along a path that includes the tube, an opening in the gasket and the fluid channel.

Abstract: The invention generally provides a static back pressure regulator. In exemplary embodiments, the static back pressure regulator includes a seat that defines part of a fluid pathway, a poppet, a spring arranged to bias the poppet toward the seat to restrict fluid flow through the fluid pathway, and a calibration element configured to adjust a force applied to the poppet by the spring. The calibration element can include a through hole that forms part of the fluid pathway. The poppet can include a first guiding portion that extends into the through hole of the calibration element and inhibits tipping of the poppet relative to the seat.

Abstract: The present disclosure relates to phase detection in multi-phase fluids where two fluid phases can be present in the fluid. Phase detection apparatus and methods are disclosed for determining the phase(s) (e.g., supercritical, liquid, and/or gas) of a fluid in a multi-phase fluid system, such as carbon dioxide based separation and chromatography system.

Abstract: Described are methods in which the retention times of a chromatographic column are adjusted through the control of the temperature of a mobile phase at the inlet to the chromatographic column. The temperature of the mobile phase at the inlet is different from the temperature of the chromatographic column. Adjustment of the temperature of the mobile phase at the inlet can be used as part of a method to transfer a chromatographic method from one liquid chromatography system to another liquid chromatography system. The method can alternatively be adapted for trapping a sample at the head of a chromatographic column to reduce the amount of band broadening of the sample from the sample injector of a liquid chromatography system. A gradient elution can then be performed to cause the concentrated volume of the analyte in the sample to elute in a tight band, resulting in improved measurement sensitivity.

Abstract: A fitting for coupling fluidic paths, such as high pressure fluidic paths in liquid chromatography systems, includes a compression nut, a tube assembly and a compression member. The compression nut has a threaded outer surface to engage a threaded bore of a receiving port and the tube assembly has an outer surface and an end face to contact a sealing surface of the receiving port. The compression member is pre-staked to the outer surface of the tube assembly at a predetermined distance from the end face and has a tapered surface to engage a surface of the receiving port. The predetermined distance permits the tube assembly to be inserted into the receiving port so that the end face makes contact with the sealing surface without the tapered surface engaging a surface of the receiving port and so that the threaded outer surface of the compression nut engages the threaded bore.