Fractionation of similar molecular weight proteins by ultrafiltration

摘要

The fractionation of protein mixtures by ultrafiltration has elicited considerable interest in the past decade. Apart from the molelcular weight difference between the proteins, the degree and effectiveness of separation is governed by the combination of membrane surface characteristics, module hydrodynamics and the feed solution environment (1-3). However with few exceptions (1-2), the studies have been confined to laboratory scale stirred units with proteins having at least a two fold difference in their molecular weights. This work explores the fractionation of similar molecular weight proteins bovine serum albumin (BSA) (65.4 kD, pl 4.8) and bovine hemoglobin (64.6kD, pl 6.8). The aim was to study and analyze the operating variables affecting the separation factor in order to determine the optimum conditions for selective separation.