EFFECT OF ADSORPTION OF CHARGED MACROMOLECULES ON STREAMING AND MEMBRANE-POTENTIAL VALUES MEASURED WITH A MICROPOROUS POLYSULFONE MEMBRANE

Changes in streaming and membrane potentials measured across a commerc ial microporous polysulfone membrane as a result of the adsorption of differently charged macromolecules were studied. Measurements were car ried out with different NaCl solutions (10(-3) M to 5 x 10(-2) M) and their mixtures with a polyanion (dextran sulfate or DS) and a polycati on (diethylaminoethyl or DEAE-dextran). From electrokinetic and electr ochemical measurements, information about characteristic membrane para meters (transport number and ionic permselectivity) and membrane/solut ion interactions (zeta potential) can be obtained. Results show how th e adsorption of charged particles affects the electrical parameters of the membrane and also its hydraulic permeability. The concentration d ependence of these parameters was also studied.