EXPLOITING INNOVATIVE DNA DELIVERY PLATFORMS BASED ON NATURAL POLYMERS AND POLY(2-OXAZOLINES)

The aim of this study was the synthesis and characterization of grafted natural polymers, which consist of poly(2-oxazoline) chains synthetized by CROP1 linked to partially quaternized chitosan or dextran. These novel materials are being used to produce polymer-DNA polyplexes towards ocular gene delivery.2 The substituted polymers were characterized by 1H NMR and SEC. The chains were used to complex the genetic material at different ratios, dynamic and electrophoretic light scattering showed stable electrostatic complexes with hydrodynamic radius ranging from 40 to 100 nm and positive charge around + 40 mV. According to agarose gel electrophoresis and fluorescence spectroscopy, complete DNA condensation is reached at N/P ~ 2 for chitosan and N/P ~ 5 for dextran. There are investigations underway to probe the transfection efficiency and cytotoxicity of the polymer-DNA polyplexes. The MTT assays preliminary demonstrated that the produced materials are nontoxic at relevant biological concentrations.