Abstract: Methods for focusing analyte peaks in liquid chromatography using a spatial temperature gradient are provided. Also provided are methods for focusing analyte peaks and improving resolution using a trap column upstream of a separation column. Further, methods are provided in which the trap column placed upstream of the separation column is packed with a temperature-sensitive polymer/copolymer, and a spatial temperature gradient is applied along the trap column for obtaining improved retentivity by trap column stationary phase, and overall improved resolution of analyte peaks.

Abstract: Exemplary embodiments are directed to methods and systems for performing online quantitative supercritical fluid extraction. An extraction cell having a known or characterized volume is loaded with a sample matrix including an analyte of interest. The extraction cell is pressurized with extraction conditions to dissolve the analyte from the sample matrix. The dissolved solution is directed from the extraction cell to a sample loop which also has a characterized volume. The dissolved solution is then directed from the sample loop to a chromatography column and subsequently to a detector. The detector output is compared against a calibration curve to determine an amount of the analyte within the sample matrix based on the known volumes of the sample loop and the extraction cell.

Abstract: Systems, methods, and devices for detecting leaks in chromatography systems are disclosed. A coating is disposed to conform to at least one component of a chromatography system, such as a fitting or a section of tubing. The coating is made of or contains a responsive material that can undergo a detectable change when exposed to a chromatographic fluid or mobile phase. The change of the responsive material can indicate the presence of the fluid or mobile phase, a change in at least one physical property of the coating to prevent passage of the fluid or mobile phase, or a combination thereof.

Abstract: Exemplary embodiments are directed to methods and systems for controlling fluid parameters within a detector. A first and second fluid pump manager control the flow of a first and second fluid to one or more heating/cooling devices, and a mixer receives and mixes the first and second fluids. An optical detector flow cell receives the fluid mixture from the mixer, and a pressure regulator controls the pressure at the optical detector flow cell. Thus, the composition, temperature, and pressure of a fluid mixture entering an optical detector flow cell can be controlled in real time.

Abstract: The disclosure relates to a system for liquid sample introduction into a chromatography system. The system includes a syringe, a first valve in fluid communication with the syringe, a second valve in fluid communication with the sample, a vessel located between, and in fluid communication with, the first and second valves, a third valve in fluid communication with the first valve, the second valve and a chromatography column, and a pump in fluid communication with the third valve and a mobile phase. When the valves are in a first position the syringe draws the sample into the vessel. The mobile phase flows to the chromatography column. When the valves are in a second position, a portion of the mobile phase flows into the vessel, mixing with and pressurizing the sample. When the valves are in a third position, the mixed and pressurized sample flows to the chromatography column.

Abstract: The disclosure relates to a system for liquid sample introduction into a chromatography system. The system includes a metering device for drawing up the liquid sample, a first multi-port valve in fluid communication with a first end of the metering device and the liquid sample, a second multi-port valve in fluid communication with a second end of the metering device and a chromatography column, and a pump in fluid communication with the second multi-port valve and a mobile phase. When the valves are in a first position the metering device draws up the liquid sample filling a portion of the metering device. When the valves are in a second position, a remaining portion of the metering device is filled with the mobile phase thereby mixing with and pressurizing the liquid sample. When the valves are in a third position, the mixed and pressurized sample flows to the chromatography column.

Abstract: In a chromatography system, including within the system an extraction vessel which receives a mixture of mobile phase and co-solvent and provides a mixture of mobile phase and co-solvent with sample to a chromatography column to increase sample concentration within the mixture. In addition, adding a reservoir to the chromatography system to form an extraction-pressurization system, wherein the mixture with sample may be collected in the reservoir and may diffuse and equilibrate to an approximately uniform sample concentration before being provided to the chromatography column. Also in addition, providing a plurality of extraction-pressurization systems to allow near-simultaneous extraction of sample and loading of the column, or concurrent extraction and loading by the plurality of extraction-pressurization systems.

Abstract: A method for estimating temperature variation due to pressure drop in a mobile phase passing through a column in a high efficiency chromatographic separation system is provided. The method includes constructing a temperature triangle using a pressure-temperature thermodynamic plot of the mobile phase having isenthalpic curves of the mobile phase. Applications of the method include development of chromatographic methods for minimizing band broadening due to temperature variation and methods to mitigate the extent of temperature variation due to the pressure drop.

Abstract: Various embodiments are generally directed to techniques for monitoring chromatographic fluid flows, such as the flow to and/or from one or more reservoirs used in chromatographic operations, for instance. In many embodiments, the chromatographic operations may include one or more of High Performance Liquid Chromatography (HPLC), Ultra Performance Liquid Chromatography (UPLC), Ultra Performance Convergence Chromatography (UPC2), and the like. Several embodiments are particularly directed to a chromatographic fluid flow device (CFFD) for monitoring a change in density of a chromatographic fluid in a tube, such as by detecting the presence or absence of gas in the tube with an ultrasonic bubble detector. In various embodiments, the chromatographic fluid may include a solvent, a sample, or waste associated with a chromatographic operation.

Abstract: Methodologies, systems, and computer-readable media are provided for controlling the mass flow rate within a CO2 based chromatography system. The pressure within a CO2 pump is measured and received at a computing system, and the computing system retrieves a target temperature value corresponding to the new pressure measurement within the CO2 pump. The computing system then generates a temperature control command that controls a CO2 pump heater or cooler in order to achieve the target temperature value at the CO2 pump. Thus, a target mass flow rate of CO2 from the CO2 pump is achieved by adjusting the temperature of the CO2 pump in response to changes in pressure.

Abstract: A liquid chromatography system, includes a fluidic flow path, a chromatography column located in the fluidic flow path, a filtration device located in the fluidic flow path before the chromatography column, the filtration device including a housing having a fluidic inlet, a fluidic outlet, wherein at least a portion of the fluidic flow path is located between the fluidic inlet and the fluidic outlet and at least one filter disposed in the portion of the fluidic flow path, wherein the at least one filter is made of a micromachined material. Liquid chromatography filtration methods are further disclosed.

Abstract: A chromatographic device includes a primary channel having a cross-sectional area and characteristic length such that analyte travel within the primary channel is substantially convective. A plurality of secondary channels each having a cross-sectional area and characteristic length such that analyte flow into and out of a secondary channel is substantially diffusive, each of the plurality of secondary channels having an entrance in fluidic communication with the primary channel wherein the entrance intersects the primary channel.

Abstract: A system and method of reducing chromatographic band broadening within a separation column include passing a mobile phase through a length of a separation column, and generating a spatial thermal gradient external to and along the length of the separation column. The spatial thermal gradient is specifically configured to counteract a particular change in a property of the mobile phase as the mobile phase passes through the separation column. For example, the particular change counteracted may be a change in density or in temperature of the mobile phase. For analytical-scale columns, for example, the spatial thermal gradient may be configured to produce temperatures external to and along the length of the separation column that substantially matches temperatures predicted to form in the mobile phase along the column length as the mobile phase passes through the separation column, thereby substantially preventing formation of a radial thermal gradient in the mobile phase.

Abstract: A significant reduction in extra-column band broadening can be achieved by decoupling the injection system from the main solvent flow line. Systems and methods for such decoupling can allow for the injection of larger volumes of sample without compromising separation yield, increase the column loading per batch, and increase the overall yield of separations. For example, a mixture of co-solvent and sample can be prepared separately from the main flow of mobile phase and co-solvent (e.g., a mixture of CO2 and methanol), loaded onto an injection loop, and then injected directly into the main flow of mobile phase and co-solvent before the chromatography column.

Abstract: Exemplary embodiments are directed to methods and systems for managing fluid decompression. A fluid connector is located downstream of a chromatography column and defines an interior bore through which a fluid can pass. The interior bore has a reduced internal diameter at a downstream end compared to an upstream portion of the fluid connector. A cooling system is configured to cool a portion of the fluid connector at or below a threshold temperature value associated with a phase separation of the fluid. A detector is located downstream of the fluid connector, and the detector is configured to receive the fluid exiting the cooled fluid connector.

Abstract: The present disclosure relates to methodologies, systems and apparatus for controlling pressure in a CO2-based chromatography system. A first pressure control element is located downstream of a CO2-based chromatography system and is disposed to control pressure within the column. A split restrictor is located downstream of the primary pressure control element and is disposed to divert a portion of the mobile phase flow to a detector. A second pressure control element is located downstream of the split restrictor and is disposed to control pressure at the restrictor. While the first pressure control element executes a pressure-controlled gradient separation, the second pressure control element maintains a constant pressure at the restrictor. During a composition-programmed gradient separation, the second control element maintains a constant pressure at the split restrictor while the first pressure control element maintains a constant average density across the column.

Abstract: In a chromatography system, including within the system an extraction vessel which receives a mixture of mobile phase and co-solvent and provides a mixture of mobile phase and co-solvent with sample to a chromatography column to increase sample concentration within the mixture. In addition, adding a reservoir to the chromatography system to form an extraction-pressurization system, wherein the mixture with sample may be collected in the reservoir and may diffuse and equilibrate to an approximately uniform sample concentration before being provided to the chromatography column. Also in addition, providing a plurality of extraction-pressurization systems to allow near-simultaneous extraction of sample and loading of the column, or concurrent extraction and loading by the plurality of extraction-pressurization systems.

Abstract: In various aspects provided are purification media and containers for dispensing a purified liquid are provided herein where a high surface area-to-volume chemically interactive purification media positioned at the outlet of a container that purifies the liquid as it is dispensed and/or extracted.

Abstract: Analytical-scale separation column assemblies include a tube with a bore packed with a stationary phase through which a mobile phase flows. In one embodiment, thermal elements are disposed remotely from and unattached to the tube. The thermal elements are in thermal communication with an external surface of the tube for producing a spatial thermal gradient outside of and along a length of the tube. In another embodiment, discrete, spatially separated strips of thermally conductive material are disposed on and wrapped around an external surface of the tube. Thermal elements are disposed remotely from the tube. Each thermal element is in thermal communication with one strip of thermally conductive material by a heat-transfer device. The thermal elements produce a spatial thermal gradient outside of and along a tube length by controlling temperature of each strip of thermally conductive material disposed on and wrapped around the external surface of the tube.

Abstract: In a sample extraction system, providing within the system two or more extraction vessel assemblies, each of which receive an extraction vessel containing the sample to be extracted and is pressurized with an extraction solvent. Additionally, providing certain changeable fluid circuits such that the extraction system may provide a sustained delivery of feed solution above or about a threshold concentration.