The present invention provides a process for preparing a functionalised polymeric chromatography medium, which process comprises (I) providing two or more non-woven sheets stacked one on top of the other, each said sheet comprising one or more polymer nanofibres, (II) simultaneously heating and pressing the stack of sheets to fuse points of contact between the nanofibres of adjacent sheets, and (III) contacting the pressed and heated product with a reagent which functionalises the product of step (II) as a chromatography medium.

The present invention provides a process for preparing a functionalised polymeric chromatography medium, which process comprises (I) providing two or more non-woven sheets stacked one on top of the other, each said sheet comprising one or more polymer nanofibres, (II) simultaneously heating and pressing the stack of sheets to fuse points of contact between the nanofibres of adjacent sheets, and (III) contacting the pressed and heated product with a reagent which functionalises the product of step (II) as a chromatography medium.

A method for producing porous particles of a cross-linked polymer, and porous particles that can be produced according to the method are disclosed. The porous particles of a crosslinked hydroxy- or amino-group-containing polymer have a relatively low swelling factor. A composite material contains the porous particles dispersed in a continuous aqueous phase. The porous particles, or the composite material, are used for purifying organic molecules and for bonding metals from solutions. A filter cartridge contains the porous particles of a cross-linked polymer or the composite material.

A method for preparation of a separation matrix, comprising the steps of: a) providing a solid support and an alkali-stable ligand derived from an immunoglobulin-binding bacterial protein; b) reacting said alkali-stable ligand with said solid support to form a separation matrix having covalently coupled alkali-stable ligands; and c) washing said separation matrix having covalently coupled alkali-stable ligands with a wash solution comprising at least 10 mM of an alkali metal hydroxide.

A method for preparation of a separation matrix, comprising the steps of: a) providing a solid support and an alkali-stable ligand derived from an immunoglobulin-binding bacterial protein; b) reacting said alkali-stable ligand with said solid support to form a separation matrix having covalently coupled alkali-stable ligands; and c) washing said separation matrix having covalently coupled alkali-stable ligands with a wash solution comprising at least 10 mM of an alkali metal hydroxide.

An object of the present invention is to provide a ligand-immobilized sea-island composite fiber in which generation of fine particles due to peeling of a sea component from an island component and generation of fine particles due to destruction of a fragile sea component are both suppressed. The present invention provides a sea-island composite fiber comprising a sea component and island components, in which a value (L/S) obtained by dividing the average total length (L) of the perimeter of all island components in a cross section perpendicular to the fiber axis by the average cross-sectional area (S) of the cross section is from 1.0 to 50.0 μm.sup.−1, a distance from the surface to the outermost island component is 1.9 μm or less, and an amino group-containing compound is covalently bonded to a polymer constituting the sea component at a charge density of 0.1 μmol or more and less than 500 μmol per 1 gram dry weight.

An object of the present invention is to provide a ligand-immobilized sea-island composite fiber in which generation of fine particles due to peeling of a sea component from an island component and generation of fine particles due to destruction of a fragile sea component are both suppressed. The present invention provides a sea-island composite fiber comprising a sea component and island components, in which a value (L/S) obtained by dividing the average total length (L) of the perimeter of all island components in a cross section perpendicular to the fiber axis by the average cross-sectional area (S) of the cross section is from 1.0 to 50.0 μm.sup.−1, a distance from the surface to the outermost island component is 1.9 μm or less, and an amino group-containing compound is covalently bonded to a polymer constituting the sea component at a charge density of 0.1 μmol or more and less than 500 μmol per 1 gram dry weight.

A separating column (12) for hippuric acid analysis is filled with a filler in which 123 μmol/g or more of β-cyclodextrin is chemically bonded to a silica matrix. By using such a filler for the separating column (12) in which 123 μmol/g or more of β-cyclodextrin is chemically bonded to the silica matrix, hippuric acid, o-methyl hippuric acid, m-methyl hippuric acid, p-methyl hippuric acid, and mandelic acid can be separated without using a mobile phase containing cyclodextrin.

A separating column (12) for hippuric acid analysis is filled with a filler in which 123 μmol/g or more of β-cyclodextrin is chemically bonded to a silica matrix. By using such a filler for the separating column (12) in which 123 μmol/g or more of β-cyclodextrin is chemically bonded to the silica matrix, hippuric acid, o-methyl hippuric acid, m-methyl hippuric acid, p-methyl hippuric acid, and mandelic acid can be separated without using a mobile phase containing cyclodextrin.

In various aspects, the present disclosure pertains to high purity chromatographic materials that comprise a chromatographic surface wherein the chromatographic surface comprises a hydrophobic modifier and an ionizable modifier comprising one or more anion exchange moieties that are positively charged when ionized, as well as devices containing such materials. In other aspects, the present disclosure provides methods for mixed mode, anion exchange reversed phase liquid chromatography comprising: (a) loading a sample comprising a plurality of acidic analytes (e.g., acidic glycans) onto a chromatographic separation device comprising such a high purity chromatographic material and (b) eluting adsorbed acidic analytes from the high purity chromatographic material with a mobile phase comprising water, organic solvent, and an organic acid salt, wherein during the course of elution a pH of the mobile phase, an ionic strength of the mobile phase, and a concentration of the organic solvent are altered over time.