Characteristic physicochemical features of the biopolymer inulin in solvent added and depleted states

The β (2 → 1) fructosyl fructose unit containing carbohydrate polymer (inulin) exhibits interesting solution properties. Its physicochemical behaviors in aqueous and aquo-organic (DMSO–water and isopropanol (IP)-water) media as well as in solvent depleted states have been investigated using viscometry, DLS, TEM and AFM methods. The solvent type and composition dependent changes in aggregation of the biopolymer have been examined. The energetics of solubility of inulin in water and IP-water media, and the salt effect on the process have been evaluated. The salting out phenomenon has been examined in terms of Hofmeister or lyotropic series. Its correlation with ionic radius, hydrodynamic radius, and lyotropic number has been tested. The molecular configurations of the polysaccharide in the solvent media have been assessed by the DLS method. In the solvent removed state, globular, rod-like and elongated fiber-like species registering fingerprint patterns of the biopolymer have been witnessed from TEM and AFM measurements.