Preparation and Swelling Study of a pH-Dependent Interpolymeric Hydrogel Based on Chitosan for Controlled Drug Release

Novel pH-dependent, biodegradable interpolymeric network (IPN) hydrogels were prepared for controlled drug release investigations. The IPN hydrogels were prepared by irradiation of solutions of N-acryloyglycine (NAGly), polyethylene glycol diacrylate (PEGDA) mixed with chitosan, in the presence of a lower amount of glutaraldehyde as the crosslinker and using 2,2-dimethoxy-2-phenyl acetophenone as the photo-initiator. The equilibrium swelling studies were carried out for the gels at 37°C in buffer solutions of pH 2.1 and 7.4 (simulated gastric and intestinal fluids, respectively). 5-Fluorouracil (5-FU) was entrapped, as a model therapeutic agent, in the hydrogels and equilibrium-swelling studies were carried out for the drug-entrapped gels at 37°C. The in-vitro release profiles of the drug were established at 37°C in pH 2.1 and 7.4.