Waters Technologies Corporation

Waters Investments Limited

Richard Wayne Andrews

Peyton C Beals

Sylvain Gilles Cormier

Hal Richardson

Geoff C Gerhardt

Keith Fadgen

Martin Gilar

Thomas S McDonald

Barry Sunray

Jordan Kornfeld

Guo-Zhong Li

Michael R Jackson

Marc E Lemelin

Theodore D Ciolkosz

Thomas E Wheat

John Lamoureux

Uwe Dieter Neue

Edward J Ognibene

John Heden

Joseph Kareh

Craig Hamilton Dobbs

Robert Tacconi

Virginia L Corbin

Steven M Binney

Thomas Mcdonald

Craig H Dobbs

Described is a mixer for a chromatography system. The mixer includes an inlet manifold channel, an outlet manifold channel and a plurality of transfer channels. The inlet manifold channel has an inlet at a proximal end of the inlet manifold channel for receiving an inlet flow. The transfer channels are fluidly connected between the inlet and outlet manifold channels. The respective fluid connections are distributed along each of the inlet and outlet manifolds channels. The transfer channels have different volumes. The mixer may be formed of a plurality of layer and the layers may be diffusion bonded to each other.

Mixer for chromatography system

A method of performing experiments on samples may include receiving criteria defining a starting state for performing an experiment in a system including a scientific instrument; determining whether the starting state is established in the system; and, responsive to the starting state being established, allowing the experiment, that analyzes a sample using the scientific instrument, to proceed. Determining whether the starting state is established may include automated monitoring of at least one parameter for at least one data channel, and determining whether all such parameters simultaneously meet associated conditions of the criteria for specified time periods. The method may include automatically monitoring the system and re-establishing the starting state prior to performing each of one or more subsequent experiments. The method may include automatically monitoring and establishing a second starting state prior to performing each of one or more additional experiments.

Techniques for determining equilibration and stability in scientific instrument systems

A chromatography system includes a gradient delay volume defined as an overall fluid volume between where gradient is proportioned until an inlet of a chromatography column, a pump pumping a flow of gradient; and at least one valve located downstream from the pump, the at least one valve having 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 at least one valve, the at least one valve having at least two positions. A first position of the at least two positions of the at least one valve increases the gradient delay volume of the chromatography system relative to when the at least one valve is in a second position.

Multi-injection mode valve module

A method for injecting a diluted sample in a chromatography system includes merging a flow of a sample and a flow of a diluent to form a flow of a diluted sample. A dilution ratio of the diluted sample equals a sum of the volumetric flow rates of the sample and the diluent divided by the volumetric flow rate of the sample. The diluted sample is stored in a holding element before injection into a chromatographic system flow. Sample dilution occurs under low pressure relative to the chromatographic flow thereby allowing lower pressure sample and diluent syringes to be used. Other benefits include reduced compressibility and a reduction in leaks due to the lower pressure operation. The method avoids problems associated with manual techniques which can introduce errors due, for example, to loss of sample, sample precipitation and adsorption of sample to vials.

Method and apparatus for injecting a chromatographic sample

Described are a method and apparatus for diluting a chromatographic sample. The method includes repeating an alternating acquisition of sample fluidic plugs each having an incremental volume of sample and diluent fluidic plugs each having an incremental volume of diluent to obtain a stack of alternating sample and diluent fluidic plugs. The stack is inserted into a flow of a mobile phase in a chromatography system. Alternatively, the method includes repeating the steps of injecting an incremental volume of sample into a chromatographic system flow and providing an incremental volume of mobile phase into the chromatographic system flow. In either implementation, the dilution ratio of the sample equals the sum of the incremental volumes of the sample and the diluent or mobile phase divided by the sum of the incremental volumes of the sample.

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.

The invention generally provides methods for improving the dynamic range of an absorbance detector and absorbance detectors having improved dynamic range. In an exemplary embodiment, the method includes receiving calibration data for a plurality of samples, the calibration data comprising an absorbance for a concentration of each of the samples, calculating a contribution of stray light to the calibration data, and correcting subsequent data by removing the contribution of stray light.

Method for extending the dynamic range of absorbance detectors

A method of preparing a liquid mixture for use in a liquid chromatography system is provided. The mixture comprises one or more acids, one or more bases, one or more salts, and one or more solvents, and the method comprises the steps of: i) calculating pH and/or salt concentration at a particular time t from a user-determined gradient function; and ii) based on the values obtained in step (i), calculating percent acid, percent base, percent salt and percent solvent in the liquid mixture at time t. A liquid chromatography system incorporating such method is also provided.

Process for preparing liquid mixtures of known pH and salt concentration

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.

Automated dilution for liquid chromatography

Described is a method of transferring a chromatographic method between liquid chromatography (LC) systems and a sample for performing the method. The method is based on a determination of an isoretention temperature at which two solutes co-elute. The method enables separations to be performed using different LC systems with reproducible and equivalent results. For example, the method allows for a chromatography method developed for HPLC to be readily transferred to a UPLC system and for a chromatography method developed for a UPLC system to be more readily transferred to a HPLC system. The method addresses LC systems having column ovens of different design in which the internal column temperatures are not equal although the operating temperatures of the column ovens may be accurately controlled to equal values. The retention behavior and resolution of different LC systems is caused to be substantially the same so that equivalent separation results are obtained.

Chromatographic sample for determining equivalent thermal conditions between liquid chromatography systems

Described is a method of transferring a chromatographic method between liquid chromatography (LC) systems. The method is based on a determination of an isoretention temperature at which two solutes co-elute. The method enables separations to be performed using different LC systems with reproducible and equivalent results. For example, the method allows for a chromatography method developed for HPLC to be more readily transferred to a UPLC system and for a chromatography method developed for a UPLC system to be more readily transferred to a HPLC system. The method addresses LC systems having column ovens of different design in which the internal column temperatures are not equal although the operating temperatures of the column ovens may be accurately controlled to equal values. The retention behavior and resolution of different LC systems is caused to be substantially the same so that equivalent separation results are obtained.

Method for determining equivalent thermal conditions between liquid chromatography systems

Disclosed is a chromatographic system and method which includes a passive pre-heater assembly. In the inventive system and method a fluid mixture is supplied from an injector to the pre-heater assembly and then to a chromatographic column having an active heating source. The pre-heater assembly includes a convoluted tube with first and second ends and a fluid passage extending centrally therebetween, first and second end fittings attached respectively to the first and second ends of the convoluted tube, and a thermally conductive film attached to an outer surface of the convoluted tube. The first end fitting is adapted for fluidly connecting the first end of the convoluted tube to the injector and the second end fitting is adapted for fluidly connecting the second end of the convoluted tube to the chromatographic column. The thermally conductive film conveys heat from an active heating source of a chromatographic column to the convoluted tube when the pre-heater assembly is positioned adjacent to the active heating source. The central fluid passage in the convoluted tube has a series of bends which function to create a secondary fluid flow field that is substantially orthogonal to a primary flow field established when fluid is traversing the fluid passage in the tube.

Passive column pre-heater with sample band spreading reduction feature

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.

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Rehoboth, MA, United States of America

Richard Wayne Andrews