BACTERIAL CELLULOSE MEMBRANE AS SEPARATION MEDIUM

A thin membrane of bacterial cellulose (BC) obtained from Acetobacter culture was tested for its performance as a dialysis membrane in aqueo us systems. The BC membrane showed superior mechanical strength to tha t of a dialysis-grade regenerated cellulose membrane, allowing the use of a thinner membrane than the latter. As a result, the BC membrane g ave higher permeation rates for poly (ethylene glycols) as probe solut es. The cutoff molecular weight of the original BC membrane, significa ntly greater than that of regenerated cellulose, could be modified by concentrated alkali treatments of the membrane. The nature of the chan ge at the ultrastructural level caused by the alkali treatments was st udied by X-ray diffraction and scanning electron microscopy. (C) 1993 John Wiley & Sons, Inc.