The resolving power of ultrafiltration

The comparison of theoretical retention curves related to the sieving mechanism of Ferry and to the distribution of membrane pores by size (PSD) with experimental curves of polymeric ultrafiltration (UF) membranes and of membranes obtained by using the surface layers of bacteria cell envelopes was carried out. It follows from this comparison that the separation mechanism in ultrafiltration has essentially a sharper character than when it is determined by Ferry's equation. It also follows that the determining factor in the resolving power of ultrafiltration is the structure of the UF membranes and especially the PSD width. Therefore, one may hope that the improvement of UF membrane structure will greatly increase the resolving power of ultrafiltration making it comparable to that of gel permeation chromatography.