Preparation of Amphiphilic Chitosan Nanoparticles for Controlled Release of Hydrophobic Drugs

The present work has been focused on the fabrication and characterization of amphiphilic chitosan nanoparticles by oil-in-water emulsion/ionic gelation technique. We elucidated the successful encapsulation of nanoparticles by FT-IR spectroscopy technique, and determined the shape, morphology and mean particle size by SEM and laser light scattering, respectively. The size of nanoparticles was about 103.5 nm by SEM and 373.95 +/- 12.8 nm by laser light scattering. The novelty of this study is the evaluation of various factors (crosslinking pH, crosslinker, and core and shell materials ratio) on encapsulation efficiency, loading capacity and release of a hydrophobic drug model such as letrozole. Encapsulation efficiency, loading capacity and release behavior of letrozole were affected by the factors. In vitro drug release studies showed an initial burst followed by a slow drug release. The amphiphilic chitosan nanoparticles prepared under lower pH and higher concentration of crosslinker agent resulted in slower letrozole release from nanoparticles. Under these conditions we observed that the release of letrozole was decreased when the concentration of core/shell materials was increased and the best release value was obtained when the concentration of core/shell materials was identical.