Several studies were done in the
past to functionalize this amino-polysaccharide in order to remove
pollutants such as metals, dyes or phenols from aqueous solutions
[25,26]. However, one inconvenience of this low-cost polysaccharide
is its swelling in aqueous solution. To circumvent this
problem, chitosan-silica hybrid materials have been elaborated by
reacting CS with Si(OEt)4 [27]