A device removing a biological and/or chemical entity (C) from extracorporeal blood (B) is disclosed. The device has a hollow capture chamber with an inlet for the entry of the extracorporeal blood (B) and an outlet for the outflow of the extracorporeal blood (B) and a capture element inside the capture chamber having a reactant surface placed in contact with the extracorporeal blood (B) and a plurality of binding agents (A) for the biological and/or chemical entity to be removed (C) such that the biological and/or chemical entity (C), upon exiting the capture chamber, is removed from the extracorporeal blood (B) as linked to the reactant surface.