HIGH-DENSITY LIGAND ATTACHMENT TO BROMINATED ALLYL MATRICES AND APPLICATION TO MIXED-MODE CHROMATOGRAPHY OF CHYMOSIN

Allylated cellulose, agarose and methacrylate matrices, activated with allyl bromide or allyl glycidyl ether, were modified by aqueous bromi nation, preferably with N-bromosuccinimide. Amine, thiol and sulphite ligands were attached efficiently and in high densities (1-1.5 mmol/g dry) to the brominated matrices, using concentrated reaction mixtures. Organic solvents were not required. Bromohydroxypropyl matrices and a mine or carboxylate derivatives could thus be used to produce matrices for all major forms of adsorption chromatography. This chemistry was used to prepare high-density mercaptoalkyl acid matrices, which were s uccessfully applied to mixed mode purification of crude chymosin and c ompared with matrices used previously. (C) 1997 Elsevier Science B.V.