Abstract: The present invention relates to a zwitterionic stationary phase comprising a carrier and at least one zwitterionic ligand bound to said carrier, said phase being suitable for HPLC separation in Hydrophilic Interaction mode, wherein the positively charged part of said zwitterionic ligand is located at the end of the ligand, and the negatively charged part of said zwitterionic ligand is located between the positively charged part and the part of said zwitterionic ligand directly binding to said carrier, or a polymeric backbone attached to the carrier, wherein the intramolecular distance between the negatively charged part of the zwitterionic ligand preferably is at most 10 atoms long. The invention also provides methods for producing said zwitterionic stationary phase and method for using the phase in HPLC separations.

Abstract: The invention relates to a polymeric material comprising crosslinked spherical particles that are obtained by photoinitiated precipitation polymerization of crosslinking monomer and optionally a further monomer in the presence of an initiator and a solvent. It also relates to a method for producing the material and a chromatography column containing the material.

Abstract: A porous silica particle suitable can be used in zwitterionic high performance liquid chromatography. The particle comprises covalently bound zwitterionic groups grafted through a polymerization reaction. A hydrophilic column packing material suitable for use as a stationary phase in zwitterionic high performance liquid chromatography may comprise porous silica particles. The particles may comprise covalently bound zwitterionic groups. Methods for manufacturing and applying the silica particles exist.

Abstract: The present invention provides porous monoliths with high flow permeability that can be produced by polymerising and divinylbenzene in the presence of an initiator, a carboxy-functionalized nitroxide stable free radical and polymeric porogens. The monoliths produced with these stable free radicals functionalized with carboxylic groups feature porosities very different from those produced by polymerizations involving other SFRs, characterized by very large surface areas in combination with relatively large through-pores. The invention also provides a method for producing the monoliths, a column containing the monoliths and an assay method using the column.

Abstract: A porous silica particle suitable can be used in zwitterionic high performance liquid chromatography. The particle comprises covalently bound zwitterionic groups grafted through a polymerization reaction. A hydrophilic column packing material suitable for use as a stationary phase in zwitterionic high performance liquid chromatography may comprise porous silica particles. The particles may comprise covalently bound zwitterionic groups. Methods for manufacturing and applying the silica particles exist.