Recent trends in hydrogels based on psyllium polysaccharide: A review

Natural polysaccharide based hydrogels display unique properties such as biodegradability, biocompatibility, stimuli-responsive characteristics and biological functions making them a materials of choice for diverse applications. Indeed during the last few years, a number of biorenewable polymers based hydrogels have attracted great interest for miscellaneous applications including biomedical, toxic ion removal and water purification. Keeping in mind the advantages of biorenewable polymers, this article summarizes for the first time, the recent development in psyllium polysaccharide based hydrogels. Different methods for preparation of polysaccharide hydrogels along with characterization, their swelling behavior and different mechanisms of solvent diffusion are critically reviewed. This article also comprehensively discusses the structure-property relationships of polysaccharide hydrogels and highlights the application potential for prime performance of the resulting hydrogels. Effect of different reaction conditions and monomers on different properties of the resulting hydrogels have been explored. The most important properties of polysaccharide hydrogels relevant to their biomedical/environmental applications are also identified, especially for the use of polysaccharide hydrogels as drug delivery/flocculant and superabsorbent systems. It is anticipated that the interest in natural polysaccharide based hydrogel will continue to grow as value - added green materials for multifunctional applications.