Abstract: The present invention relates to magnetic, polymeric polyvinylalcohol-based carrier materials. The surface of said materials is at least partially silanised. The invention also relates to a method for silanising the surface of such materials and to the use of the magnetic, silanised carrier materials for isolating biological material, preferably nucleic acids.

Abstract: Biological materials in a mixture of substances are separated, detected or quantified using magnetic spherically shaped cross-linked polyvinyl alcohol (PVAL) polymer particles ranging in size from 1 to 10 &mgr;m. The particles containing a coupled ligand are used to bind a biological material in a mixture of substances, and the particles containing bound biological material are isolated from the mixture. The particles are prepared by dispersing a magnetic colloid containing a magnetic material such as a ferromagnetic or superparamagnetic substance in an aqueous solution of polyvinyl alcohol containing reactive hydroxyl groups, adding the resultant mixture to an organic phase containing a mixture of at least two emulsifiers, and adding a water-soluble cross-linking agent such as a dialdehyde that reacts with the hydroxyl groups of polyvinyl alcohol to form the polymer particles.