Polysaccharide based superabsorbent hydrogels and their methods of synthesis: A review

Since the emergence of a new concept "superabsorbent polymer" also referred as "slush powder" in 1950s, considerable interest and rapid progress have been put by scientist and industrialist to meet the demand. Superabsorbent hydrogels (SAHs), 3D hydrophilic networks of polymer chains; that absorb and retain aqueous solutions up to hundreds of times of their own weight while maintaining its network intact. The most widely used and commercially available SAHs are synthetic Na-polyacrylate. The tendency of replacing them with "greener" option is due to their poor degradability, biocompatibility and high cost. The affinity for water makes them useful in personal hygiene, agriculture, construction, water purification, drug delivery, etc. The reviewed SAHs in this article are purely saccharide based such as: starch, cellulose, chitosan, guargum, cyclodextrin, etc. with their chemical and physical synthesis. The discussed information will be very helpful to design bio-friendly and low-cost SAHs for biomedical and agricultural purposes.