SOME FACTORS DETERMINING PROTEIN AGGREGATION DURING ULTRAFILTRATION

The factors contributing to protein aggregation in albumin ultrafiltra tion were investigated as a function of operation conditions. The natu re of protein deposits was examined by electron microscopy. Protein ag gregation appears to occur as a result of rapid supersaturation of pro tein molecules and high solvent velocity (shear) in the concentrated l ayer near the membrane surface. The shear occurring in the solvent flo w on the membrane surface probably unfolds protein molecules and thus promotes flocculation due to collision between particles.