A method of purification and/or separation of glycopeptides and quantitation of same. The method includes contacting a sample comprising glycopeptides to a hydrophilic enrichment substrate under conditions that permit the glycopeptides to bind to the hydrophilic enrichment substrate. The glycopeptides are eluted from the hydrophilic enrichment substrate with an ammonium formate and acetonitrile (ACN) in water solution to create an enriched glycopeptide sample, which may be subjected to analysis to identify specific glycopeptides.

The invention herein describes a method to purify a target oligonucleotide using hydrophobic interaction chromatography (HIC). The method includes adding a salt to a mixture of the target oligonucleotide and product-related impurities, applying the diluted mixture, at a particular dynamic loading capacity, to the hydrophobic interaction chromatography resin (or hydrophobic adsorbent), washing the hydrophobic adsorbent with an aqueous salt solution, eluting the target oligonucleotide with a eluting solution, and collecting the eluent comprising the target oligonucleotide.

A method for separating steviol glycoside, including: a separating step 55 of performing a continuous liquid chromatography for continuously separating at least one type of steviol glycoside by allowing a liquid to be separated containing plural types of steviol glycosides to pass through a separating agent in which polyethylene imine is immobilized to a carrier.

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 chromatography column for the use of separation of acidic sugar chains, wherein the column comprises a first column and a second column, the second column connected by a flow path downstream of an outlet of the first column, and selected from the following (1) or (2): (1) the carrier of the first column is hydrophobically modified silica having a group containing a primary amine, a secondary amine or/and a tertiary amine, and the carrier of the second column is a resin having a group containing a primary amine, a secondary amine or/and a tertiary amine; (2) the carrier of the first column is a resin having a group containing a primary amine, a secondary amine or/and a tertiary amine, and the carrier of the second column is hydrophobically modified silica having a group containing a primary amine, a secondary amine, or/and a tertiary amine.

Methods of LC-MS analysis of oligonucleotides free of ion-pairing reagents are disclosed herein. Historically, ion-pairing reagents have been used for acceptable extraction and chromatography prior to mass spectral analysis. The disclosure herein presents methods free of ion-pairing reagents at each stage, from extraction through the LC-MS endpoint. The methods improve assay reliability and reproducibility, extend column lifetimes, and decrease instrumental downtime previously necessary to remove ion-pairing reside. Also disclosed herein are systems for performing these methods.

Methods of LC-MS analysis of oligonucleotides free of ion-pairing reagents are disclosed herein. Historically, ion-pairing reagents have been used for acceptable extraction and chromatography prior to mass spectral analysis. The disclosure herein presents methods free of ion-pairing reagents at each stage, from extraction through the LC-MS endpoint. The methods improve assay reliability and reproducibility, extend column lifetimes, and decrease instrumental downtime previously necessary to remove ion-pairing reside. Also disclosed herein are systems for performing these methods.

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.

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.