257results about "Chromatographic cation exchangers" patented technology

The present invention relates to a method of separating antibodies from contaminants in a solution, which method comprises contacting the solution with a chromatography resin comprised of a support to which multi-modal ligands have been immobilised, wherein a multi-modal ligand comprises at least one cation-exchanging group and at least one aromatic or heteroaromatic ring system. In one embodiment, the ring-forming atoms of the aromatic or hereoaromatic entity are selected among C, S or O, and the cation exchanging group is a weak cation exchanger. The present method may be used as a single step procedure or as a polishing step following a capture on a Protein A column.

A method for making an ion exchange coating (e.g., a chromatographic medium) on a substrate comprising (a) reacting at least a first amine compound comprising amino groups, with at least a first polyfunctional compound, in the presence of a substrate to form a first condensation polymer reaction product, with a first unreacted excess of either at least said first amino group or polyfunctional compound functional moieties, irreversibly attached to the substrate, and (b) reacting at least a second amine compound or at least a second polyfunctional compound with unreacted excess in the first condensation polymer reaction product to form a second condensation polymer reaction product, and repeating the steps to produce the desired coating. A coated ion exchange substrate so made.

Novel material for chromatographic separations, processes for its preparation, and separations devices containing the chromatographic material. In particular, the disclosure describes porous inorganic / organic hybrid particles having a chromatographically-enhancing pore geometry, which desirably may be surface modified, and that offer more efficient chromatographic separations than that known in the art.

The present invention provides an agglomerated multimodal chromatographic medium. the medium of the invention includes groups active in anion exchange, cation exchange and hydrophilic interaction chromatographic modalities. The invention provides methods of making these media and using them in separations of analytes. Also provided are separations devices incorporating the medium and systems incorporating these separations devices.

Permeable polymeric monolithic materials are prepared in a plastic column casing. In one embodiment, the permeable polymeric monolithic materials are polymerized by the application of heat from an external source starting at a low temperature such as 40 degrees centigrade, depending on the mixture and size of the column, and continuing at a higher temperature, such as 60 degrees centigrade. The temperature at the start of the polymerization is low enough so as not to cause exothermal run-away conditions and to avoid high heat of reaction that would prevent a substantially constant temperature across the cross-section of the column. The higher temperature is used after sufficient monomer depletion has occurred and steric interference has increased so the polymerization reaction is sufficiently slow to avoid heat of reaction generation high enough to cause significant reduction in the homogeneousness of the pore sizes.