In the specification, a method for purifying a compound by column chromatography, and a method for optimizing the symmetry factor and theoretical plate number by allowing the slurry to settle and reducing the sedimentation volume of the slurry. A compound purified by such method is also provided.

Stationary phase for preparative High Pressure Liquid Chromatography (HPLC) for preparative separation of Rare Earth Elements (REEs), the stationary phase comprising porous particles suitable for HPLC having a non-polar surface being impregnated with ligands binding REEs, wherein the porous particles has a pore size of 300 or higher, is described.

Stationary phase for preparative High Pressure Liquid Chromatography (HPLC) for preparative separation of Rare Earth Elements (REEs), the stationary phase comprising porous particles suitable for HPLC having a non-polar surface being impregnated with ligands binding REEs, wherein the porous particles has a pore size of 300 or higher, is described.

A gas chromatography device for peak focusing of one or more target analytes is provided that include a chromatographic column with an inlet and an outlet. A stationary phase is deposited inside the chromatographic column and has a positive thickness gradient. The stationary phase extends from the inlet to the outlet and has a first thickness at the inlet of the chromatographic column and a second thickness at the outlet of the chromatographic column. The second thickness is at least about 10% greater than the first thickness. Methods of peak focusing in a gas chromatography device, method of verifying peak focusing in a gas chromatography device and creating a gas chromatography device having a chromatographic column with a positive thickness gradient are also provided.

A gas chromatography device for peak focusing of one or more target analytes is provided that include a chromatographic column with an inlet and an outlet. A stationary phase is deposited inside the chromatographic column and has a positive thickness gradient. The stationary phase extends from the inlet to the outlet and has a first thickness at the inlet of the chromatographic column and a second thickness at the outlet of the chromatographic column. The second thickness is at least about 10% greater than the first thickness. Methods of peak focusing in a gas chromatography device, method of verifying peak focusing in a gas chromatography device and creating a gas chromatography device having a chromatographic column with a positive thickness gradient are also provided.

There is provided a system for separation of analytes in a solution. The system encompasses a cartridge or trapping column enclosing a sorbent for binding the analytes in the solution and a conduit establishing a fluid link to a valve having a holding-loop to achieve elution through the cartridge at low pressures. Prior to entry into the loop, the eluent is diluted or modified by a confluent flow stream. The valve is switchable to a position following the elution from the cartridge for emptying the holding loop through an outlet port at high pressures comparable to those required for chromatographic columns. The system may use parallel gradient formation/elution to stagger analyses so that essentially the only analytical phase that hinders a 100% duty cycle is the time required for moving the first analyte from the valve and to the detector.

There is provided a system for separation of analytes in a solution. The system encompasses a cartridge or trapping column enclosing a sorbent for binding the analytes in the solution and a conduit establishing a fluid link to a valve having a holding-loop to achieve elution through the cartridge at low pressures. Prior to entry into the loop, the eluent is diluted or modified by a confluent flow stream. The valve is switchable to a position following the elution from the cartridge for emptying the holding loop through an outlet port at high pressures comparable to those required for chromatographic columns. The system may use parallel gradient formation/elution to stagger analyses so that essentially the only analytical phase that hinders a 100% duty cycle is the time required for moving the first analyte from the valve and to the detector.

The present disclosure provides methods, compositions, and kits for the rapid release, labeling, and detection of O-glycans present on a glycoconjugate, such as a glycoprotein, glycopeptide, peptidoglycan, or proteoglycan of interest. The compositions and methods allow the released O-glycans to be subjected to high-throughput analysis.

Functionalized fluorescent tracers, compositions, and methods for extracting the functionalized fluorescent tracers from oil phases and other wellbore or drilling fluids are provided. In some implementations, a sorbent for extracting tracer molecules from a fluid includes a silica-based sorbent. The silica-based sorbent includes a hydrophobic functional group and an ionic functional group. In some implementations, the ionic functional group is positively charged. In some implementations, the ionic functional group is negatively charged. A method of extracting a functionalized dye from an oil phase includes mixing a sorbent for extracting tracer molecules with an oil phase sample that includes a functionalized fluorescent tracer, recovering the sorbent from the oil phase, and dispersing the sorbent in an organic solvent. In some implementations, the method includes lowering the pH of the organic solvent. In some implementations, the method includes raising the pH of the organic solvent.

Functionalized fluorescent tracers, compositions, and methods for extracting the functionalized fluorescent tracers from oil phases and other wellbore or drilling fluids are provided. In some implementations, a sorbent for extracting tracer molecules from a fluid includes a silica-based sorbent. The silica-based sorbent includes a hydrophobic functional group and an ionic functional group. In some implementations, the ionic functional group is positively charged. In some implementations, the ionic functional group is negatively charged. A method of extracting a functionalized dye from an oil phase includes mixing a sorbent for extracting tracer molecules with an oil phase sample that includes a functionalized fluorescent tracer, recovering the sorbent from the oil phase, and dispersing the sorbent in an organic solvent. In some implementations, the method includes lowering the pH of the organic solvent. In some implementations, the method includes raising the pH of the organic solvent.