FOULING AND PROTEIN ADSORPTION - EFFECT OF LOW-TEMPERATURE PLASMA TREATMENT OF MEMBRANE SURFACES

Adsorption of proteins and the effect of the chemical nature of membra ne surfaces on protein adsorption were investigated using C-14-tagged albumin and several microporous membranes (polyvinilydene fluoride, PV DF; nylon; polypropylene, PP; and polycarbonate, PC). The membrane sur faces were modified by exposing them to low-temperature plasma of seve ral different monomers (n-butane, oxygen, nitrogen alone or as mixture s) in a radiofrequency plasma reactor. Transients in the permeability of albumin solutions through the membranes and changes in flux of dist illed water through the membranes before and after adsorption of album in were used to investigate the role of protein adsorption on membrane fouling. The results show that the extent of adsorption of albumin on hydrophobic membranes was considerably more than that on hydrophilic membranes. The hydrophilic membranes were susceptible to electrostatic interactions and less prone to fouling. A pore-blocking model was suc cessfully used to correlate the loss of water flux through pores of de fined geometry.