Background: Despite great hopes for small interfering RNA (siRNA)-based gene therapies,
restrictions, including the presence of nucleases, reticuloendothelial system and undesired electrostatic
interactions between nucleic acids and the cell membrane, limit the success of these approaches.
In the last few decades, non-viral nucleic acid delivery vectors in nanosize with high biocompatibility,
low toxicity and proton sponge effect have emerged as magic bullets to overcome
Objective: This study aimed to develop poly(2-hydroxyethyl methacrylate) (pHEMA)-chitosan
nanoparticles (PCNp), and to transfect green fluorescent protein (GFP)-silencing siRNA (GsiR) in
Methods: Firstly, PCNp displaying core-shell structure were synthesized and thereafter GsiR was
encapsulated into the core of PCNp. The synthesized PCNp with/without GsiR were characterized
using ultraviolet-visible (UV-vis)-spectroscopy, Fourier-transform infrared (FTIR) spectroscopy,
thermal decomposition, atomic force microscopy (AFM), scanning electron microscopy (SEM), zeta
potential and dynamic light scattering (DLS) measurements. Encapsulation of siRNA into the
pHEMA core coated with chitosan shell was demonstrated using fluorescence and FTIR spectroscopy.
Results: The surface charges of PCNp and PCNp-GsiR were found to be +39.5 and +40.2, respectively.
In DLS analysis, an insignificant shift in the Z-average diameter of PCNp was observed from
109 nm to 133 nm using the encapsulation of GsiR. In comparison to other studied nanomaterials and
a commercial transfection reagent, our findings suggest a promising GFP-silencing effect of 45%.
Conclusion: To our knowledge, we have obtained comparable silencing activity with the other studied
equivalents despite using the lowest concentration of siRNA in existing literature.