Preparation of an asymmetric semipermeable membrane with anticoagulant activity.

In this paper we report the preparation of a new asymmetric semipermeable styrene-isoprene-styrene block-copolymer membrane. Its modification by addition of gaseous N-chlorosulphonylisocyanate alters neither its permselectivity nor its water permeability rate. This modified membrane possesses an antithrombic activity which depends on antithrombin III. The actual active surface in contact with proteins is very large because the whole macroporous underlayer is modified and accessible to the proteins.