[Microcapsules with modulable properties made with cross-linked proteins and polysaccharides]

A cross-linking process was applied to mixtures of a protein (gelatin A or B) and a polysaccharide. Mixed-walled microcapsules were then obtained, which exhibited properties different from those of microcapsules prepared from the protein alone. They were shown to be more resistant to enzymatic lysis and this effect depended on the ratio of the polysaccharide, on its nature and on the cross-linking pH. Very hydrophilic microcapsules were obtained through cross-linking of gelatin admixed with alginate or carboxymethylcellulose. The addition of alginate to gelatin resulted in a slower release of encapsulated pilocarpine.