Sacrificial functional polystyrene template to prepare chitosan nanocapsules and in vitro drug release properties

In this study, biocompatible and biodegradable chitosan (CS) nanocapsules are successfully prepared in abundant and easily using carboxyl-functionalized polystyrene (PS) as sacrificial template and cross-linked CS with glutaraldehyde as the shell. First, the monodisperse functionalized PS templates be about 200 nm are made by emulsifier-free emulsion polymerization. Second, nanocapsules are accomplished by fabricating on the basis of chemical cross-linking on the surface of the PS template and removing the core via tetrahydrofuran. The templates and nanocapsules were characterized by FT-IR, H-1 NMR, FESEM, and TEM. All the results confirmed that the nanocapsules are accomplished via this method. By dissolution of ibuprofen in the chloroform droplets when prepare the carboxyl-functionalized PS, drug-loaded nanocapsules are also fabricated. It is found that the loaded drug can be released again in a sustained manner for up to 80 h. The nanocapsules walls have a prominent effect in slowing down the drug release rate.