Waters Technologies Corporation

James Usowicz

Marc E Lemelin

Russell Keene

Joshua A Burnett

Theodore D Ciolkosz

Joshua A Shreve

Theodore A Dourdeville

Peyton C Beals

Lucas O Tiziani

Tony A Lin

Michael R Jackson

Kurt D Joudrey

Miguel Soares

Aaron Lebeau

Stanislaw Koziol

Neal B Almeida

Christopher Seith

Douglas P Wittmer

Maruth Sok

Kara O'Donnell

Theodore C Ciolkosz

Wen Lu

Daniel J Gagne

Nathan Barrett

Joseph A Jarrell

Keith Fadgen

Mark W Moeller

Paul B Keenan

Robert A Jencks

Kenneth R Plant

John Lamoureux

John M Auclair

Senthil Bala

John Heden

Daniel J McCormick

Emily J Berg

Edwin H Denecke

Richard Kent

Roy J MacKinnon

Richard S Threlfall

Brett G Cook

Michael J Cook

Keith McGrath

Jae Hong Park

Matthew Richard Gill

Thomas Andrew Lutzow

Sukhdev Bangar

Chromatography system

Bottle cap

The present disclosure relates to methodologies, systems and apparatus for cooling pump heads and providing balanced cooling and heat transfer between multiple pump heads. Multi-pump systems that are used to pump fluids that vary greatly in density with minor changes in temperature, such as the mobile phase of a C02-based chromatography system, require highly stable temperature conditions. In order to achieve a substantially equal average heat transfer between multiple pump heads and a coolant fluid, coolant fluid may be flowed through coolant passageways within the pump heads in a recursive and/or parallel coolant flow patterns. Such recursive and/or parallel coolant fluid flow patterns provide increased stability in temperature, compressibility, and density of the fluids passing through a multi-pump system.

Cooling of pump heads in carbon dioxide chromatography systems

Described are a fraction collector and a method of fraction collection for a liquid chromatography system. The method includes diverting a liquid chromatography system flow from a waste channel to a collection tube at a start of a fraction collection window and collecting the system flow dispensed from the collection tube during the fraction collection window. At the end of the window, the system flow is diverted to the waste channel and a flow of a wash solvent is provided to the collection tube to dispense liquid remaining in the collection tube at the end of the window from the collection tube. The method can increase the amount of the collected fraction and can reduce or eliminate cross-contamination of a subsequently collected fraction. The method is useful for analytical scale applications where the collected fractions may have volumes defined by a limited number of drops dispensed from the collection tube.

Method of fraction collection for a liquid chromatography system

Described is an apparatus for controlling a position of a sample in a liquid chromatography system. The apparatus includes a rotary drive mechanism, a stepper motor and a rotational coupling system such as a drive belt and pulley system. The rotational coupling system transfers the rotational motion of a motor shaft to a shaft of the rotary drive mechanism. Advantageously, the stepper motor is remote to the sample compartment for improved safety in the event that volatile gas accumulates within the sample compartment. The rotary drive mechanism can be configured in a small form factor and can provide highly stable rotation of an attached sample tray to accommodate the requirements of compact liquid chromatography systems. In addition, leakage from inside the sample compartment to the ambient environment is substantially reduced or eliminated, resulting in better thermal control of the sample compartment.

Apparatus for controlling sample position in a liquid chromatography system

The present disclosure relates to methodologies, systems and apparatus for cooling pump heads and providing balanced cooling and heat transfer between multiple pump heads. Multi-pump systems that are used to pump fluids that vary greatly in density with minor changes in temperature, such as the mobile phase of a CO2-based chromatography system, require highly stable temperature conditions. In order to achieve a substantially equal average heat transfer between multiple pump heads and a coolant fluid, coolant fluid may be flowed through coolant passageways within the pump heads in a recursive and/or parallel coolant flow patterns. Such recursive and/or parallel coolant fluid flow patterns provide increased stability in temperature, compressibility, and density of the fluids passing through a multi-pump system.

A device comprising a pressure monitor and a control means that receives a signal representing measured pressure at the pressure monitor and controls the controllable elements of a fluid system is utilized to monitor a fluid system for error conditions, to optimize operations and to diagnose the fluid system. By following a testing protocol that selectively enables parts of the system, the control means narrows the list of possible falling components. Comparing the measured pressure against normal pressures allows the device to identify error conditions. Determining the volume of fluid being transported and controlling the duration of the flow optimizes operation of the fluid system.

Pressure monitor optimization of fluid path utilization

A method includes passing a mobile phase fluid flow comprising liquefied CO2 through a separation column; then introducing a makeup fluid flow into the mobile phase fluid flow to form a mixed fluid flow; and then splitting the mixed fluid flow.

Flow splitting in supercritical fluid chromatography systems

Apparatus and method measure the flow rate of fluid for use in calibrating fraction collection in a chromatography system. An injector inserts a detectable substance into a flow of fluid. A first detector, disposed in a path of the flow of liquid with the substance, produces a signal in response to detecting the substance in the flow of fluid. A second detector, disposed downstream from the first detector in the path of the flow of fluid with the substance, produces a signal in response to detecting the substance in the flow of fluid. A computing system receives each signal produced by the first and second detectors upon detecting the substance in the flow of fluid, and computes a volumetric flow rate of the flow of fluid based on a time interval between the signals and a volume of the path between the first and second detectors.

Liquid flow rate measurement device

Described is a dispensing needle for a fraction collector. The dispensing needle includes a conduit having a fluid channel to conduct a chromatographic flow, an interior wall that defines the fluid channel, an exterior surface and an endface through which the chromatographic flow is dispensed. The dispensing needle also includes a coating of a hydrocarbon material or a fluorocarbon material that is bonded to the endface. The coating is also bonded to at least a portion of the exterior surface that is adjacent to the endface and at least a portion of the interior wall that is adjacent to the endface. The coating operates to reduce a droplet volume of a liquid dispensed from the endface that may remain at the tip of the dispensing needle. Consequently, the concentration variation in a collected fraction due to a missing droplet or extra droplet is reduced.

Dispensing needle for a fraction collector

A supercritical fluid chromatography system is provided with an injection valve subsystem for introducing a sample into a flow of mobile phase fluid. The injection valve subsystem includes an auxiliary valve and an inject valve. The operations of the auxiliary and inject valves are coordinated in such a manner as to reduce sample carry-over and system pressure perturbations occurring during sample injection.

Introducing samples into supercritical fluid chromatography systems

A device comprising a pressure monitor and a control means that receives a signal representing measured pressure at the pressure monitor and controls the controllable elements of a fluid system is utilized to monitor a fluid system for error conditions, to optimize operations and to diagnose the fluid system. By following a testing protocol that selectively enables parts of the system, the control means narrows the list of possible failing components. Comparing the measured pressure against normal pressures allows the device to identify error conditions. Determining the volume of fluid being transported and controlling the duration of the flow optimizes operation of the fluid system.

Pressure monitor optimizaiton of fluid path utilization

The present invention provides a method and apparatus for substantially eliminating destructive transients of pressure or flow rate which can degrade the efficiency and useful lifetime of chromatography columns. The present invention enables a substantially constant flow of mobile phase liquid to be maintained through the chromatography system by eliminating the flow blockage interval associated with the actuation of sample injection valves. The present invention further provides a method to reduce the pressure and flow rate transients associated with pressurization of the sample loop contents when the sample loop is introduced to chromatography system delivery pressure.

Method and apparatus for sample injection in liquid chromatography

Described are techniques for use with a sealing member forming a static seal or a dynamic seal at a surface thereof. The sealing member has at least the surface thereof formed from one of VESPEL&#xae; SCP 5000 material or VESPEL&#xae; SCP 50094 material.

Static and dynamic seals

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Webster, MA, United States of America

James Usowicz