Protein adsorption onto tentacle cation-exchange hollow-fiber membranes

S. A. CAMPERI; A. A. NAVARRO DEL CAÑIZO; F. J. WOLMAN; E. E. SMOLKO; O. CASCONE; M. GRASSELLI

BIOTECHNOLOGY PROGRESS

American Chemical Society

Año: 1999 vol. 15 p. 500 - 505

8756-7938

A sulfonic group (up to 200 ímol/mL) membrane was incorporated to epoxy-activated microporous hollow fibers to obtain high-capacity convective ion exchangers. The pure water flux through the membrane decreased exponentially with sulfonic group density and protein binding capacity increased accordingly. At sulfonic group density of 70 mmol/mL, the membrane lysozyme maximum binding capacity was 84 (9 mg/mL in comparison with its theoretical monolayer maximum binding capacity of 20 mg/mL, thus evidencing tentacle formation. After a cycle of adsorption in a 30 mM sodium phosphate buffer, pH 7.0, adsorbed lysozyme could be quantitatively recovered following elution with 0.5 M NaCl in the same buffer. Dynamic capacity for lysozyme was 67% of maximum binding, and this value did not change at space velocities ranging from 10 to 40 min-1 as shown by the superimposition of the corresponding breakthrough curves. A cartridge assembled with 21 fibers showed a dynamic-to-static capacity ratio for lysozyme of 0.60 with 1 mg/mL pure lysozyme solution, and 0.42 with a particulate feed composed of 1 mg/mL lysozyme and 0.1 mg/mL yeast.