Abstract: Methods for transferring a separation procedure from a first chromatographic system to a second one are disclosed that involve substantially matching a pressure profile. In some such methods, a length, an area, and a particle size of a first column in the first system and a flow rate in the first separation procedure are identifiable. Some such methods also involve selecting a combination of a length, an area, and a particle size of a second column in the second system and a flow rate for the second separation procedure. These methods may involve calculating a target length, a target area, or a target particle size for the second column in the second system or a target flow rate for the second separation procedure.

Abstract: The present disclosure relates generally to a system and a method for improving performance of a chromatography system using a highly-compressible fluid based mobile phase (e.g., CO2). In particular, the present disclosure relates to a system that uses a conduit, such as a convergent-divergent nozzle, for reducing pressure noise in a chromatography system using a highly-compressible fluid based mobile phase. The chromatography system can include a conduit, such as a convergent-divergent nozzle, disposed downstream of the column to reduce or prevent the propagation of pressure or density pulses from a back pressure regulator.

Abstract: The present disclosure relates generally to a system of method development in a highly-compressible fluid based chromatography system. In particular, the disclosure relates to method development in a carbon dioxide based chromatography system which can avoid non-laminar flow conditions. The system can include characterization of the chromatographic system in the form of one or more charts that can be used during method development to select chromatographic separation conditions that avoid non-laminar flow. For example, the onset of non-laminar conditions can be plotted as a function of volumetric flow rate and the mobile phase composition, e.g., carbon dioxide: methanol (v/v %).

Abstract: A significant reduction in extra-column band broadening can be achieved by decoupling the injection system from the main solvent flow line. In addition, by decoupling the injection system from the main solvent flow line, additional components (e.g., filters, valves, etc.) can be introduced into the chromatography system without increasing the negative band broadening effects. Systems and methods herein provide not only for such decoupling but also for filtering precipitates from the system. As a result, a larger volume of sample can be injected into the present systems without compromising separation yield. In addition, an increase the column loading per batch, an increase the overall yield of separations, and greater system efficiency (i.e., less time lost for cleaning and maintenance) can be realized.

Abstract: Methods for transferring a carbon dioxide based separation procedure from a reference chromatographic system to a target chromatographic system involve alternative techniques for determining system pressure drops not attributable to the column. One technique involves leveraging experimental chromatography to develop a correction factor that is a function of at least one correction coefficient and at least one ratio of the differential analyte retention time to the retention time in the reference system. Another technique involves leveraging other experimental measurements of tubing pressure drops under various condition to develop a lookup table that can be used to identify likely tubing pressure drops in the target system. A third technique leverages knowledge of the separation procedure and the target system and the likely nature of the relevant flow to calculate tubing pressure drops in the target system.

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: 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: Solvent containers and solvent container trays for chromatography systems are described for providing control over solvent supply and waste collection. Designated solvent containers and exclusively designated solvent containers provide solvents for use by chromatography systems. Control over solvent supply is achieved by requiring matched container shape and container receiving position shape within the tray, and additionally or alternatively, through solvent container coding readable by the solvent tray and chromatography system which provide information about the solvent container to the chromatography system.

Abstract: Systems, methods, and devices for detecting leaks in chromatography systems are disclosed. The leak detection system includes a sealable compartment disposed to surround at least one component of a chromatography system. The detector is in communication, e.g., fluid communication, with an interior of the sealable compartment and configured to detect the leak by various mean including the presence of liquid or the presence of vapor, or both within the sealable compartment.

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: The present disclosure generally relates to systems, methods and devices for providing pressurized solvent flow in chromatography 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: 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: 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.