Preparation and physico-chemical characterisation of microporous polysaccharidic hydrogels

A new technique to realise microporous structure was realised. It permits to obtain a microporous structure directly on the already crosslinked hydrogel. It consits in stratifying the already crosslinked hydrogel onto a filter with a known porosity and forcing the CO2 bubbles, deriving from the addition of HCl to a porogen salt, to cross through the filter first and the matrix then. Changing the filter porosity it was possible to modulate the porous morphology of the hydrogels. The selected polysaccharides were hyaluronane, alginate and carboxymethylcellulose. The influence of the porous morphology on the gel physico-chemical properties has been evaluated by FT-IR, FRAP, calorimetric, absorption and rheological analysis