The present disclosure relates to a method of separating a compound of interest, particularly unsaturated compound(s) of interest, from a mixture. The compound is separated using a column having a chromatographic stationary phase material for various different modes of chromatography containing a first substituent and a second substituent. The first substituent minimizes compound retention variation over time under chromatographic conditions. The second substituent chromatographically and selectively retains the compound by incorporating one or more aromatic, polyaromatic, heterocyclic aromatic, or polyheterocyclic aromatic hydrocarbon groups, each group being optionally substituted with an aliphatic group. In some examples, the present disclosure can include a chromatographic system having a chromatographic column having a stationary phase with a chromatographic substrate containing silica, metal oxide, an inorganic-organic hybrid material, a group of block copolymers, or a combination thereof.

A composition includes a hybrid ligand. The hybrid ligand includes an amine group, an amide group or a sulfonamide group, and hydroxyl groups. A first method includes providing a solution containing a first polar analyte and a second polar analyte, applying the solution to a stationary phase including an immobilized hybrid ligand, applying an elution solvent to the stationary phase such that the first polar analyte and the second polar analyte pass through the stationary phase with different elution times, and collecting the first polar analyte at a first elution time and collecting the second polar analyte at a second elution time after the first elution time. A device of a packed column, a cartridge, a tube, a well plate, a membrane, or a planar thin-layer chromatography plate includes a solid support and a hybrid ligand coupled to the solid support. A second method forms an immobilized hybrid ligand.

Low-retention pre-columns that allow increased injection volumes of solvents chromatographically stronger than the mobile phase and use of solvents with limited solubility in the mobile phase, such as ethyl acetate and MTBE. The system and method also reduces band broadening due to the extra-column effects acting upstream of the analytical column, including band broadening due to the injection process and due to the connecting tubing and fittings between the injection system and the column. A pre-column may also be used as a guard column, thereby minimizing band broadening due to the guard column.

A laterally-fed membrane chromatography device for removing a solute from a fluid is provided. The device has a top plate, a middle plate and a bottom plate. The top plate has an inlet and a top channel for directing the fluid from the inlet towards a membrane stack. The middle plate houses the membrane stack. The membrane stack has a leading edge for receiving the fluid from the top channel, a trailing edge for distributing the fluid to the bottom channel, and is configured to remove the solute from the fluid as the fluid passes through the membrane stack. The bottom plate has a bottom channel and an outlet. The bottom channel is for directing the fluid from the membrane stack to the outlet. The top channel directs the fluid form the inlet over the leading edge in a direction that is transverse to the direction of flow of the fluid through the membrane stack.

A laterally-fed membrane chromatography device for removing a solute from a fluid is provided. The device has a top plate, a middle plate and a bottom plate. The top plate has an inlet and a top channel for directing the fluid from the inlet towards a membrane stack. The middle plate houses the membrane stack. The membrane stack has a leading edge for receiving the fluid from the top channel, a trailing edge for distributing the fluid to the bottom channel, and is configured to remove the solute from the fluid as the fluid passes through the membrane stack. The bottom plate has a bottom channel and an outlet. The bottom channel is for directing the fluid from the membrane stack to the outlet. The top channel directs the fluid form the inlet over the leading edge in a direction that is transverse to the direction of flow of the fluid through the membrane stack.

A chromatography device for removing a solute from a fluid is provided. The device has a first plate having an inlet and a first channel. The first channel directs the fluid from the inlet towards chromatographic media housed in a chamber coupled to the first plate. The chamber has a leading edge for receiving the fluid from the first channel and a trailing edge for delivering the fluid to a second channel. The chromatographic media is configured to remove the solute from the fluid as the fluid passes through the chamber. The device also has a second plate coupled to the chamber having the second channel and an outlet. The second channel directs the fluid from the chamber to the outlet. The direction of flow of fluid through the first channel and the second channel is transverse to a direction of flow of the fluid through the chromatographic media. A method of removing a solute from a fluid is also provided.

A chromatography device for removing a solute from a fluid is provided. The device has a first plate having an inlet and a first channel. The first channel directs the fluid from the inlet towards chromatographic media housed in a chamber coupled to the first plate. The chamber has a leading edge for receiving the fluid from the first channel and a trailing edge for delivering the fluid to a second channel. The chromatographic media is configured to remove the solute from the fluid as the fluid passes through the chamber. The device also has a second plate coupled to the chamber having the second channel and an outlet. The second channel directs the fluid from the chamber to the outlet. The direction of flow of fluid through the first channel and the second channel is transverse to a direction of flow of the fluid through the chromatographic media. A method of removing a solute from a fluid is also provided.

A method of forming a frame around a membrane stack for a laterally-fed membrane chromatography device is provided. The method includes placing a membrane stack having one or more membrane layers on a bottom surface of body of a master mold, the body having opposed side walls and opposed end walls, the opposed side walls spaced apart by a distance greater than a length of the membrane stack, the opposed end walls spaced apart by a distance greater than a width of the membrane stack; placing a cap on the body of the master mold to enclose the membrane stack in the master mold, the cap having at least one opening for injecting a material into a space defined by the end walls of the master mold, the side walls of the master mold, end walls of the membrane stack side walls of the membrane stack, the bottom surface of the body and an inner surface of the cap; injecting the material into the space around the membrane stack; and curing the material to form a frame around the membrane stack.

A method of forming a frame around a membrane stack for a laterally-fed membrane chromatography device is provided. The method includes placing a membrane stack having one or more membrane layers on a bottom surface of body of a master mold, the body having opposed side walls and opposed end walls, the opposed side walls spaced apart by a distance greater than a length of the membrane stack, the opposed end walls spaced apart by a distance greater than a width of the membrane stack; placing a cap on the body of the master mold to enclose the membrane stack in the master mold, the cap having at least one opening for injecting a material into a space defined by the end walls of the master mold, the side walls of the master mold, end walls of the membrane stack side walls of the membrane stack, the bottom surface of the body and an inner surface of the cap; injecting the material into the space around the membrane stack; and curing the material to form a frame around the membrane stack.

The present disclosure relates to the determination of analytes in a sample using chromatography. The present disclosure provides methods of separating an analyte from a sample. A mobile phase is flowed through a chromatography column. The mobile phase includes about 0.005% (v/v) to about 2.50% (v/v) difluoroacetic acid and less than about 100 ppb of any individual impurity, especially metal impurities. A sample including the analyte is injected into the mobile phase. The analyte is separated from the sample.