Apparatus for the treatment of blood by extracorporeal circulation and process of manufacture

Process for improving the biocompatibility of an apparatus for the treatment of blood or plasma by extracorporeal circulation, the apparatus having a compartment for the circulation of blood provided with two accesses, the process comprising the steps of:

• depositing in the blood compartment, at at least one of the accesses, a determined quantity of a substance in a form such that the substance is capable of undergoing, substantially without deterioration, an irradiation capable of sterilizing the apparatus, the substance being capable of dissolving in an aqueous solution and of durably bonding to an inner surface of the blood compartment in order to increase biocompatibility of the inner surface of the blood compartment, the determined quantity of the substance being determined such that the circulation of a determined volume of aqueous solution through the blood compartment, starting from the access where the determined quantity of the substance has been deposited, should result in the formation, by durable bonding, of at least one molecular layer of the substance on the inner surface of the blood compartment;
• sterilizing the apparatus;
• and
• before the utilization of the apparatus, circulating the determined volume of aqueous solution through the blood compartment, starting from the access where the determined quantity of the substance has been deposited, so as to carry the substance into contact with the inner surface of the blood compartment and to cause the formation of at least one durable molecular layer of the substance on the inner surface of the blood compartment.