The present investigation describes the synthesis and the characterization of a novel highly stable polysaccharidic hydrogel system, designed for modified drug delivery. Gels and films based on the biodegradable and biocompatible chitosan (CS) were prepared by a crosslinking reaction between the polysaccharide amino groups with tartaric acid, using the short-range crosslinkers 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) and N-hydroxysuccinimide (NHS) as coupling agents. The aim of the study is to characterize the novel CS hydrogel by means of rheological and mechanical measurements; in vitro swelling, release, and degradation studies were also carried out. Obtained results show how the structure of the obtained networks can deeply affect dynamomechanical properties of the hydrogel as well as the delivery rate of loaded model drugs. The mechanical characterization of the hydrogel, in the form of films, indicates that the film elasticity increases as the water content in the hydrogel increases. Rheological studies evidenced that the different network structures can affect the elastic modulus of the system. Release studies of two model molecules, i.e., vitamin B12 and blue dextran, of different steric hindrance were carried out using both the bulk gel and the film. In vitro release of both drugs was evaluated in water and in Hepes to assess the suitability of this novel drug delivery system for pharmaceutical applications. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 123:842-849, 2012