Abstract

Purpose: To prepare chitosan-modified paclitaxel-loaded PLGA nanoparticles and evaluate their cytotoxicity in vitro. Method: The parameters of the emulsion solvent diffusion process were optimized. The ratio of the water phase to the organic phase (v/v), the concentration of chitosan solution and the dose of paclitaxel were investigated with regard to the particle size and encapsulation efficiency. The micromeritic properties of the nanoparticles were also investigated. Results: The optimized formulation had the following characteristics: the ratio of the water phase to the organic phase was 6:1 (v/v), the chitosan concentration was 0.2% (v/v), and the dose of paclitaxel was 3 mg. The average particle size and encapsulation efficiency were 105 nm and 91.2%, respectively. The Zeta potential of the nanoparticles was changed from negative (– 6.71 mV at 25.6˚; –6.5 mV at 34.2˚) to positive (+39.9 mV at 25.6˚; +40.5 mV
at 34.2˚) after the nanoparticles were modified by chitosan. Difference scanning calorimetry (DSC) studies indicated that paclitaxel encapsulated in the nanoparticles was in the form of a solid dispersion and spherical nanoparticles were observed under a scanning electron microscope. The drug release profile exhibited was that of sustained-release of the nanoparticles. Cytotoxicity experiments in vitro showed that the chitosan-modified nanoparticles have a greater cell killing potential than chitosan-unmodified nanoparticles. Conclusions: Chitosan-modified PLGA nanoparticles were successfully prepared by the emulsion-solvent diffusion method and exhibited excellent cytotoxicity in vitro.


Keywords:  Emulsion-solvent diffusion   Paclitaxel   PLGA   Nanoparticles   Chitosan