Chemically modified xanthan and gellan for preparation of biomaterials for ophthalmic applications
Résumé
Gellan and xanthan are extracellular polysaccharides with very interesting rheological or gelling properties. They are esterified with acrylic acid, acryloyl chloride or maleic anhydride. Consequently, due to the presence of carbon double bonds, hydrogels are obtained using a grafting–crosslinking process with N-isopropylacrylamide and N′-bisacrylamide. Such hydrogels, due to the presence of poly(N-isopropylacrylamide), are thermosensitive and present drug release properties which can be adjusted through the reaction conditions. This concept was demonstrated for ophthalmic applications.