The potentiometric determination of the degree of acetylation was carried out following the method given by Muzzarelli[21]. Chitosan was dissolved in an excess of acid and titrated with 0.1 M NaOH. The volume of base used between the two inflexion points observed on the titration curve corresponded to the acid consumed for the salification of amine groups and allowed the determination of the degree of acetylation of the chitosan.