The invention relates to a sorbent having improved selective properties for removing protein-bound substances from a biological liquid, especially blood or blood plasma of patients suffering from severe disorders of the liver function or liver failure or renal insufficiency, the sorbent comprising: (a) a porous, neutral, hydrophobic polymer and (b) a polypeptide layer which is adsorbed to the polymer, the neutral, hydrophobic polymer having an average pore size of at least 15 nm. The invention further relates to methods and uses in conjunction with such a sorbent. The invention is especially used in the extracorporeal liver support.
