Preparation and Characterization of CS/(β-CD)/PAA Composite Hydrogels for Controlled Drug Delivery

Novel macroporous composite hydrogels were synthesized by free radical polymerization of crylic acid (AA), chitosan (CS) and beta-cyclodextrin (β-CD) with N,N-methylenebisacrylamide (MBA) as the cross-linking agent. The structure of the resultant hydrogels was characterized by the Fourier Transform Infrared Spectrum (FT-IR) spectroscopy and Scanning Electron Microscopy (SEM). The thermal stability was also investigated by thermal gravimetric analyzer. The swelling properties were investigated in detail. The results revealed that the prepared hydrogels exhibited high pH sensitivity and well reversible property by undergoing a number of swelling/de-swelling recycles. Nicotinamide was chosen as a model drug to evaluate the controlled drug release behavior. The results indicated that the release rate decreased with the increasing of β-CD content in acidic solution (pH=1.80).