Abstract: The object of the invention is a unit element forming a membrane comprising a semi-permeable material able to separate in two compartments a filtration device for extracorporeal treatment of a fluid such as blood or plasma, said material being negatively charged, said element having a first internal face intended to be in direct contact with blood or plasma and a second external face intended to be in contact with filtrate, wherein said second face of said element is treated on the surface by one selected in the group comprising at least a cationic polymer, a mixture of polymers of which at least one polymer is cationic. The unit element can also have said first face treated on the surface by one selected in the group comprising: at least one cationic polymer, a mixture of polymers of which at least one polymer is cationic.

Abstract: The object of the invention is a unit element forming a membrane comprising a semi-permeable material able to separate in two compartments a filtration device for extracorporeal treatment of a fluid such as blood or plasma, said material being negatively charged, said element having a first internal face intended to be in direct contact with blood or plasma and a second external face intended to be in contact with filtrate, wherein said second face of said element is treated on the surface by one selected in the group comprising at least a cationic polymer, a mixture of polymers of which at least one polymer is cationic. The unit element can also have said first face treated on the surface by one selected in the group comprising: at least one cationic polymer, a mixture of polymers of which at least one polymer is cationic.

Abstract: The object of the invention is a unit element forming a membrane comprising a semi-permeable material able to separate in two compartments a filtration device for extracorporeal treatment of a fluid such as blood or plasma, said material being negatively charged, said element having a first internal face intended to be in direct contact with blood or plasma and a second external face intended to be in contact with filtrate, wherein said second face of said element is treated on the surface by one selected in the group comprising at least a cationic polymer, a mixture of polymers of which at least one polymer is cationic. The unit element can also have said first face treated on the surface by one selected in the group comprising: at least one cationic polymer, a mixture of polymers of which at least one polymer is cationic.

Abstract: A module for extracorporeal purification of a biological fluid includes at least one support or wall defining a compartment which is delimited by an ionic functionalized support or wall, the surface of which is bonded by ionic bonds to a first molecule or macromolecule which exhibits free amine groups to which are covalently bonded a second molecule or macromolecule which exhibits free carboxylic groups which can directly or indirectly form amide, ester or thioester bonds. The invention also includes methods of producing such module.