Polyelectrolyte three layer nanoparticles of chitosan/dextran sulfate/chitosan for dual drug delivery.

In this work, dual drug loaded in chitosan/dextran sulfate/chitosan (CS/DEX/CS) nanoparticles was synthesized by layer-by-layer (LBL) self-assembly technique for use in anti-cancer drug delivery. The nanoparticles were characterized in terms of particle size, zeta-potential, encapsulation efficiency and morphology (SEM and TEM). The in vitro release of the dual drugs, inner PTX and outer 5-Fu, from the CS-PTX/EX/CS-5Fu nanoparticles with different numbers of CS and DEX layers and different PBS was characterized. The results revealed that the pH-sensitive dual drug loaded nanoparticles exhibited a controlled release profile, and the release mechanism followed Two-phase kinetic model for PTX and Higuchi model for 5-Fu. Subsequently the cytotoxicity of nanoparticles was evaluated against HepG2 cells using MTT and apoptosis assay, resulting in synergistic effects between dual drugs and enhanced inhibition to cancer cells. Cellular uptake studies demonstrated efficient internalization of PTX and 5-Fu in HepG2 cells. Therefore the dual drug loaded CS/DEX/CS nanoparticles had good prospects for the biomedical delivery application.