Separation of glucose oxidase and catalase using ultrafiltration with 300-kDa polyethersulfone membranes

This work examines the separation of glucose oxidase (GOx) and catalase by ultrafiltration using 300 kDa MWCO polyethersulfone membranes. The effects of solution pH and ionic strength on the transmission of a single protein (either GOx or catalase) were quantified using the pulsed sample injection technique. Other effects including stirring speed and permeate flux on separation of the binary protein mixtures were also studied using parameter scanning ultrafiltration. Under optimized conditions, glucose oxidase transmission could reach more than 47% and the purity obtained in the permeate was greater than 93% after one stage ultrafiltration process even with higher molar ratio of catalase in the feed.