Basic features of the polyamide membranes.

Progress in membrane and membrane process development have contributed to the continuous improvement of the extracorporeal treatment of renal failure during the last 40 years. Today membranes can be adapted to the specific needs required by their clinical application. Synthetic structures like the polyamide membranes offer a wide range of possibilities in performance and hemocompatibility, due to: (1) the use of block polymers or polymer blends and mixtures, and (2) modification of membrane structure, pore size and porosity, due to changes of the preparation process. However, further improvements are still required to achieve the ultimate goal of matching the performance of biological membranes.