A separating material formed by a solid substrate having a substrate surface, primary or secondary amines coupled to the substrate surface, and a graft polymer formed on the substrate by covalently coupling the primary or secondary amines with a thermally labile radical initiator and subsequently contacting the substrate surface with a solution of one or more polymerizable monomers. Methods for the extracorporeal treatment of blood, blood plasma or blood serum employing the separating material, for affinity adsorption, ion-exchange adsorption, hydrophobic adsorption, or hydrophilic adsorption employing the separating material, and a separating column employing the separating material are also disclosed.
