A method for separating diastereomers of pristane. A pristane sample is prepared, and then injected into a chromatographic instrument equipped with a chiral chromatographic column, where a stationary phase of the chiral chromatographic column has a preset pore size. The pristane diastereomers in the pristane sample are separated by the chiral chromatographic column, and the components produced by the separation of the pristane diastereomers sequentially enter a mass spectrometer for detection and analysis.

Chiral polymer microspheres have a porous structure of a concentric multi-shell structure. Each layer of the multi-shell structure is optically and structurally anisotropic. The optical axes of adjacent layers have a sequential slight twist. All layers of the multi-shell structure generate a helix configuration and the chiral polymer microspheres are optically active. A method for preparing the chiral polymer microspheres, includes: forming a homogeneous liquid crystal mixture; dispersing the liquid crystal mixture into a continuous phase to form liquid crystal droplets through an emulsification process; polymerizing the reactive liquid crystal to form intermediate microspheres; and removing the one non-reactive liquid crystal and the chiral additive to form the chiral polymer microspheres. The chiral polymer microspheres have a porous structure and a swelling ability, and can be used as the stationary phase in chiral chromatograph, improving separation efficiency.

A separation medium for removing small molecules from biomacromolecule in aqueous mixtures comprises gel filtration chromatography beads having a nominal protein fractional range of about 1000 Da to about 5000 Da and having an internal adsorbent matrix derived from a hydrophobicized scaffold. The gel filtration chromatography beads remove small molecules that are less than 1500 Da and have log Pow values greater than about −0.5 from biomacromolecules in aqueous mixtures. Devices containing the separation medium are also provided.

Disclosed are composite materials and methods of making them. The composite materials comprise a support member and a cross-linked gel, wherein the cross-linked gel is a polymer synthesized by thiol-ene or thiol-yne polymerization and cross-linking. The cross-linked gel may be functionalized by a thiol-ene or thiol-yne grafting reaction, either simultaneously with the polymerization or as the second step in a two-step procedure. The composite materials are useful as chromatographic separation media.

Provided are a novel chitosan compound represented by Formula (I) and a separating agent for optical isomers. In Formula (I), each R is independently a group represented by Formula (II) or a group represented by Formula (III); R.sup.a is an alkyl group having from 1 to 5 carbons or an alkyl group having from 3 to 5 carbons and having a branched chain; and n is an integer of 5 or greater; and in Formulas (II) and (III), each R.sup.b is independently an unsubstituted phenyl group, a phenyl group having a substituent, an unsubstituted cylohexyl group, or a cyclohexyl group having a substituent, and each of the substituent is independently an alkyl group having from 1 to 5 carbons, or a halogen.

Chiral polymer microspheres have a porous structure of a concentric multi-shell structure. Each layer of the multi-shell structure is optically and structurally anisotropic. The optical axes of adjacent layers have a sequential slight twist. All layers of the multi-shell structure generate a helix configuration and the chiral polymer microspheres are optically active. A method for preparing the chiral polymer microspheres, includes: forming a homogeneous liquid crystal mixture; dispersing the liquid crystal mixture into a continuous phase to form liquid crystal droplets through an emulsification process; polymerizing the reactive liquid crystal to form intermediate microspheres; and removing the one non-reactive liquid crystal and the chiral additive to form the chiral polymer microspheres. The chiral polymer microspheres have a porous structure and a swelling ability, and can be used as the stationary phase in chiral chromatograph, improving separation efficiency.

The present invention provides novel chromatographic materials, e.g., for chromatographic separations, processes for its preparation and separations devices containing the chromatographic material; separations devices, chromatographic columns and kits comprising the same; and methods for the preparation thereof. The chromatographic materials of the invention are high purity chromatographic materials comprising a chromatographic surface wherein the chromatographic surface comprises a hydrophobic surface group and one or more ionizable modifier.

The present invention provides novel chromatographic materials, e.g., for chromatographic separations, processes for its preparation and separations devices containing the chromatographic material; separations devices, chromatographic columns and kits comprising the same; and methods for the preparation thereof. The chromatographic materials of the invention are high purity chromatographic materials comprising a chromatographic surface wherein the chromatographic surface comprises a hydrophobic surface group and one or more ionizable modifier.

The present invention relates to a method to improve chromatography beads. More closely, the invention relates to a novel method for production of dextran-containing porous media and chromatography media produced with this method. In the method, the chromatography media is subjected to dextranase-treatment leading to improved pressure-flow properties of the media.

The present invention relates to a method to improve chromatography beads. More closely, the invention relates to a novel method for production of dextran-containing porous media and chromatography media produced with this method. In the method, the chromatography media is subjected to dextranase-treatment leading to improved pressure-flow properties of the media.