Formulation and in vitro characterization of PEGylated chitosan and polyethylene imine polymers with thrombospondin-I gene bearing pDNA.

An ideal gene carrier is required both in safety and efficiency for transfection. We examined the use of water soluble chitosan and polyethyleneimine as a carrier for anti-angiogenic protein, TSP-1 coded, in gene delivery. The aim of this study was to synthesize and characterize polyethylene glycol conjugated cationic polymers to increase anti-angiogenic gene transfection and reduce possible cytotoxicity. Gel electrophoresis study showed strong DNA binding ability of modified cationic polymers. Also structural properties of pegylated polymers were confirmed by (1)H-NMR. We investigated in vitro properties of PEG conjugated and coated particles which were observed between 145 and 250 nm with the positive zeta potential value. In addition, the chitosan-based DNA complexes did not induce remarkable cytotoxicity against MCF-7 cells. Due to low cytotoxicity, we observed high transfection efficiency at chitosan-based formulations compared with PEI ones. Although transfection studies carried on in vitro conditions, we measured slight increases at transfection with PEGylation. PEG-conjugated chitosan formulations can be a promising candidate due to its efficiency in condensing and transfection of pDNA, its low cytotoxicty and comparatively high encapsulation degree.