Abstract: Cellulose Sulfate (CS) is a sulfated polysaccharide derivative, which shows a variety of biological activities such as anticoagulation etc.The molecular weight is the key factor to affect the biological activitiesa ndb iological utilizationo fC S.Hence ultra-filtration membranes with the cut-off molecular weight of 10K and 4K were adopted respectively for the fractionation of the CS mixed component. The structure of each fraction was investigated. Results indicated that three fractions i.e.“ above 10K”,“ between 4K and 10K”, and“ below 4K” were obtained respectively after two ultra-filtration procedures. The weight percentage of the above fractions in the mixed components was 55.9%, 16.7% and 18.5% respectively. The intrinsic viscosity and the sulfur content of the fractions decreased according to the order of“ above 10K”,“ between 4K and 10K”, and“ below 4K”. The“ above 10K” fraction exhibited optical rotation property. The“ below 4K”raction showed no metachromasia on azure A and its IR spectrum was different from that of the rest fractions.

Key words: cellulose sulfate, ultrafiltration, fractionation, biological activity