Preparation and Gene Silencing Efficiency of Chitosan-based siRNA Nano-carriers

This study is to prepare chitosan-based siRNA nano-carriers (Chi-TPP-siRNA) using ionic gelation between cationic chitosan and anionic tripolyphosphate (TPP) for delivery of siRNA to cytoplasm. We studied the effect of the molecular weight of chitosan and the mole ratio of chitosan/TPP on the physicochemical properties of Chi-TPP nanoparticles by using dynamic light scattering and electron microscopy. The siRNA encapsulation was evaluated by using electrophoresis. The biological properties of Chi-TPP-siRNA on MDA-MB-231 cells were evaluated by using confocal laser microscopy. The resulting Chi-TPP-siRNAs, using control siRNA, were formed in sphere shape. The diameter and the PdI value of Chi-TPP-siRNA were 223.5 nm and 0.229, respectively. The cell viability of Chi-TPP-siRNA at the concentration of 500 mu g/mL was above 88%. Green fluorescent protein (GFP) silencing effect of Chi-TPP-siGFP was evaluated to be 48.1%. In conclusion, the biocompatible nano-carrier, Chi-TPP-siRNA, could be used in various gene therapy.