Abstract: Provided herein is a multi-component chromatographic material and use thereof for reversed-phase liquid chromatography. The multi-component chromatographic materials provided herein comprise a chromatographic core having an exterior surface; and at least two different hydrophobic ligands covalently bound to the exterior surface with a total surface coverage less than 2.0 ?mol/m2. The multi-component chromatographic materials of the present technology are beneficial for reversed-phase liquid chromatography using highly aqueous mobile phases. For example, chromatographic materials described herein allow mitigating or preventing significant retention loss of reversed-phase liquid chromatography columns after flow interruption.

Abstract: Described is a mixer for a liquid chromatography system. The mixer includes a flow distributor, a mixing disk and a flow collector. The mixer includes an inlet face, an outlet face and a plurality of channels each having an inlet end at the inlet face and an outlet end at the outlet face. The channels have a flow direction anisotropy between the inlet and outlet faces. A compositional solvent stream received at the flow distributor is distributed across the inlet face of the mixing disk and the flow collector collects the distributed solvent composition stream after passing through the mixing disk. The mixing disk may include a dispersive medium having a random porous structure. A retention time distribution of the mixer may depend on the structure of the channels between the inlet and outlet faces of the mixing disk.

Abstract: The present disclosure discusses a method of separating and/or purifying polynucleotides. The method includes injecting a sample into a chromatographic column that is packed with a porous sorbent having a pore size that substantially excludes the polynucleotides from the sorbent. This restricted access to the sorbent allows separation of large polynucleotides from each other and from smaller molecular weight impurities.

Abstract: Described is a mixer for a liquid chromatography system. The mixer includes an inlet, an outlet, a first flow channel, and a second flow channel. The inlet receives a fluid flow to be mixed and the outlet provides the mixed fluid flow. Each of the two flow channels is coupled between the inlet and the outlet. The second flow channel includes an offset volume that delays fluid propagation through the second flow channel relative to the first flow channel. The offset volume includes a coiled channel which increases radial dispersion and decreases axial dispersion of a fluid flowing through the offset volume, thereby enabling a further reduction in periodic noise in a detector baseline signal as compared to known split flow mixers for liquid chromatography systems.

Abstract: The exemplary embodiments may provide liquid chromatography systems that are smaller in size and with reduced extra-column volume than conventional liquid chromatography systems. The exemplary embodiments may reduce the size of the liquid chromatography systems enough that the liquid chromatography systems of the exemplary embodiments may be deployed adjacent to automated sample preparation robotics, adjacent to a process stream, or adjacent to the inlet of a mass spectrometer. In addition, the exemplary embodiments may reduce the extra-column volume of the liquid chromatography system by eliminating many of the connection tubes found in conventional liquid chromatography systems and by situating components of the liquid chromatography system in closer proximity.

Abstract: The disclosure relates to a gradient twin column recycling chromatography method that is used to separate a mixture containing closely eluting compounds. In one embodiment, a sample includes a primary organic compound and one or more impurities that closely elute with the primary organic compound. A gradient mobile phase is initially used to remove unwanted early eluting and late eluting impurities from the sample. After the gradient removal of some of the impurities is complete, the remaining mixture of the primary organic compound and the closely eluting impurities are separated using recycle chromatography methodology with an isocratic mobile phase.

Abstract: Disclosed herein are chromatography columns with conical or reducing inside dimensions and improved fits for use therewith, along with methods for making the columns and the frits.

Abstract: The disclosure relates to a recycling chromatography method that includes injecting a sample into a mobile phase flow stream of a chromatography system to create a combined flow stream. The sample includes an API and at least one impurity. The chromatography system includes a first column and a column in series, a first valve in fluid communication with the first and second chromatographic columns, a heater in communication with the first and second chromatographic columns, a fraction collector in fluid communication with the first and second chromatographic columns, and a second valve positioned before the fraction collector. The combined flow stream is recycled from the first chromatographic column to the second chromatographic column and vice versa by switching the first valve until a baseline resolution is achieved to separate the at least one impurity from the API. The at least one impurity is collected in the fraction collector.

Abstract: Described is a mixer for a liquid chromatography system. The mixer includes a flow distributor, a mixing disk and a flow collector. The mixer includes an inlet face, an outlet face and a plurality of channels each having an inlet end at the inlet face and an outlet end at the outlet face. The channels have a flow direction anisotropy between the inlet and outlet faces. A compositional solvent stream received at the flow distributor is distributed across the inlet face of the mixing disk and the flow collector collects the distributed solvent composition stream after passing through the mixing disk. The mixing disk may include a dispersive medium having a random porous structure. A retention time distribution of the mixer may depend on the structure of the channels between the inlet and outlet faces of the mixing disk.

Abstract: A mixer arrangement for use in a chromatography system includes a first frequency targeting mixer including a first flow channel coupled between an inlet and an outlet and a second flow channel coupled between the inlet and the outlet, the second flow channel including a volume offset region configured to delay fluid propagation through the second flow channel, wherein the volume offset region is configured to reduce or eliminate fluidic compositional oscillations in a compositional solvent stream that depart from a desired composition at a first target frequency, and a residual noise targeting mixer fluidically connected in series to the frequency targeting mixer, the residual noise targeting mixer configured to dampen aperiodic baseline noise in the compositional solvent stream.

Abstract: Exemplary embodiments may compensate for expected frictional heating or Joule-Thomson cooling in chromatography columns. Frictional heating or Joule Thomson cooling are the same thing for a fluid decompressing along a porous material. Either heat is absorbed from or released to the external environment. The exemplary embodiments may cool the mobile phase to a sub-ambient temperature before the mobile phase passes through a chromatography column to compensate for the frictional heating or heat the mobile phase to a super-ambient temperature to compensate for Joule-Thomson cooling. The amount of temperature increase expected from the frictional heating or the amount of temperature decrease expected from the Joule-Thomson cooling may be calculated or estimated. Based on the amount of temperature increase or decrease expected, the set point for the heater/cooler may be determined and applied to the mobile phase.

Abstract: The exemplary embodiments may determine a temperature set point for an outlet heater or cooler based on available information without requiring user input or requiring only minimal user input. The exemplary embodiments may estimate the temperature set point of the outlet heater based on available information, such as pressure delta along the column, temperature at the inlet of the chromatography column, and volumetric flow rate. In some instances, the estimate may be normalized for column dimensions, such as length and diameter. Tailing factor may also be used in determining the estimate. The estimate is not computationally burdensome and can be recalculated as the chromatography column is in use.

Abstract: A liquid chromatography system including a solvent delivery pump for delivering a mobile phase through the liquid chromatography system, an injector for injecting a sample into the mobile phase, a column for effecting a separation of components of the sample, and a dispersive element positioned between the injector and the column, the dispersive element configured to dilute a sample solvent in the mobile phase prior to entering the column is provided. Further dispersive elements, systems, and methods are also provided.

Abstract: The disclosure relates to a recycling chromatography method that includes injecting a sample into a mobile phase flow stream of a chromatography system to create a combined flow stream. The sample includes an API and at least one impurity. The chromatography system includes a first column and a column in series, a first valve in fluid communication with the first and second chromatographic columns, a heater in communication with the first and second chromatographic columns, a fraction collector in fluid communication with the first and second chromatographic columns, and a second valve positioned before the fraction collector. The combined flow stream is recycled from the first chromatographic column to the second chromatographic column and vice versa by switching the first valve until a baseline resolution is achieved to separate the at least one impurity from the API. The at least one impurity is collected in the fraction collector.

Abstract: The technology relates to a recycling chromatography method. A sampled is injected into a mobile phase flow stream of a liquid chromatography system creating a combined flow stream. The liquid chromatography system includes at least two columns positioned in series, a valve in fluid communication with the at least two columns, and a detection cell positioned between the at least two columns. The combined flow stream is flowed through the at least two columns and chromatographic peaks of the sample are monitored by the detection cell. The detection cell is configured to measure resolution and width of the chromatographic peaks and automatically switch the valve from a first position to a second position when the measured resolution is less than a desired resolution, the measured width is less than a maximum combined peak width, and a switch count is less than a predetermined maximum number of switches.

Abstract: A method of performing a chromatographic separation includes generating a spatial temperature gradient along a length of a chromatographic column in a liquid chromatography system. A sample is injected into a flow of a mobile phase to the column and a flow of a mobile phase having a composition gradient is provided to the column after the sample is received at the column. The spatial temperature gradient is moved along the length of the column from the column inlet to the column outlet during the time that the composition gradient traverses the column. This coordination of the composition gradient with the movement of the spatial thermal gradient yields a significant increase in peak capacity per unit time compared with conventional separation techniques performed in a conventional isothermal column environment.

Abstract: A process for avoiding formation of an Si—SiO2—H2 environment during a dissolution treatment of a semiconductor-on-insulator structure that includes a carrier substrate, an oxide layer, a thin layer of a semiconductor material and a peripheral ring in which the oxide layer is exposed. This process includes encapsulating at least the exposed oxide layer of the peripheral ring with semiconductor material by performing a creep thermal treatment; and performing an oxide dissolution treatment to reduce part of the thickness of the oxide layer. In this process, the semiconductor material that encapsulates the oxide layer has a thickness before the oxide dissolution that is at least twice that of the oxide that is to be dissolved, thus avoiding formation of an Si—SiO2—H2 environment on the peripheral ring where the oxide layer would otherwise be exposed.

Abstract: A process for avoiding formation of a Si—SiO2—H2 environment during a dissolution treatment of a semiconductor-on-insulator structure that includes a carrier substrate, an oxide layer, a thin layer of semiconductor material and a peripheral ring in which the oxide layer is exposed. This process includes encapsulating at least the exposed oxide layer of the peripheral ring with semiconductor material by performing a creep thermal treatment; and performing an oxide dissolution treatment to reduce part of the thickness of the oxide layer. In this process, the semiconductor material that encapsulates the oxide layer has a thickness before the oxide dissolution that is at least twice that of the oxide that is to be dissolved, thus avoiding formation of a Si—SiO2—H2 environment on the peripheral ring where the oxide layer would otherwise be exposed.

Abstract: A process for treating a semiconductor-on-insulator type structure that includes, successively, a support substrate, an oxide layer and a thin semiconductor layer. The process includes formation of a silicon nitride or silicon oxynitride mask on the thin semiconductor layer to define exposed areas at the surface of the layer which are not covered by the mask, and which are arranged in a desired pattern; and application of a heat treatment in a neutral or controlled reducing atmosphere and under controlled conditions of temperature and time to induce at least a portion of the oxygen of the oxide layer to diffuse through the thin semiconductor layer, thereby resulting in the controlled reduction in the oxide thickness in the areas of the oxide layer corresponding to the desired pattern. The mask is formed so as to be at least partially buried in the thickness of the thin semiconductor layer.

Abstract: A process for treating a semiconductor-on-insulator type structure that includes, successively, a support substrate, an oxide layer and a thin semiconductor layer. The process includes formation of a silicon nitride or silicon oxynitride mask on the thin semiconductor layer to define exposed areas at the surface of the layer which are not covered by the mask, and which are arranged in a desired pattern; and application of a heat treatment in a neutral or controlled reducing atmosphere and under controlled conditions of temperature and time to induce at least a portion of the oxygen of the oxide layer to diffuse through the thin semiconductor layer, thereby resulting in the controlled reduction in the oxide thickness in the areas of the oxide layer corresponding to the desired pattern. The mask is formed so as to be at least partially buried in the thickness of the thin semiconductor layer.