Chemically Cross-Linking Effects on the Sorption of Heavy Metal Ions to Hydrogels of Cyanobacterial Megamolecules, Sacran

Abstract

Cyanobacterial polysaccharides, sacrans, are anionic megamols. having extremely high mol. wts. (Mw: 1.6 * 107). We confirmed by FT-MS analyses that sacran is composed of various partial structures such as continuous and combination structures of uronic acids and hexoses. We used highly swollen sacran gels (swelling degree: 700-800 times of dry wt.) prepd. by chem. crosslinking with diamines such as 1-lysine. Sacran gels shrank and clouded in aq. solns. of In and Gd ions and showed more than 100 times adsorption ratios of these metal ions compared with non cross-linked sacran presumably due to continuous uronic acids.