Characterization and in vitro cytotoxicity of doxorubicin-loaded γ-polyglutamic acid-chitosan composite nanoparticles

In this study, gamma-polyglutamic acid (gamma-PGA) and chitosan (CS) nanoparticles were characterized as a carrier for the anti-cancer drug doxorubicin (DOX). Using ionic complexation between the positively charged DOX and the negatively charged polyelectrolyte gamma-PGA, DOX:gamma-PGA complexes were produced with an efficiency of approximately 99%. SEM micrographs demonstrated that the complexation of gamma-PGA and DOX alone does not lead to the formation of nanoparticles and that the addition of a third component, chitosan, is required. Drug-loaded DOX:gamma-PGA:CS nanoparticles were produced with particle sizes ranging from similar to 150 to similar to 630 nm. The stability of the DOX:gamma-PGA:CS nanoparticles was examined by suspending the nanoparticles in different kinds of aqueous media. For the first time, in vitro studies with DOX-loaded nanoparticles demonstrated the cytotoxicity of the nanoparticles against a human oral squamous cell carcinoma cell line (HN-5a). Non-drug-loaded gamma-PGA:CS nanoparticles did not display cytotoxic effects. It was shown that the encapsulated or surface-bound DOX did not lose its bioactivity and the prepared drug-loaded particles exhibited a considerable anti-proliferative activity against the human cancer cell line. (C) 2013 Elsevier B.V. All rights reserved.