Patent ID: 8388847

Claim:
A method for concentrating shear sensitive biopolymers, the method comprising flowing a mixture comprising a shear sensitive biopolymer and a solution buffer into a hollow fiber dialysis module to form a retentate, said retentate having a shear sensitive biopolymer concentration that is greater than that of the mixture, and a filtrate, wherein a transmembrane pressure between the mixture and the filtrate is about 1 mmHg to about 150 mmHg, wherein a membrane thickness of the hollow fiber dialysis module is less than about 200 micrometers, and wherein a wall shear rate in the hollow fiber dialysis module is less than about 2300 sec −1 wherein the shear sensitive biopolymer present in the retentate retains an activity of at least 70% of the activity of the sensitive biopolymer present in the mixture.