Halloysite nanotubes-carbon dots hybrids multifunctional nanocarrier with positive cell target ability as a potential non-viral vector for oral gene therapy

Hypothesis: The use of non-viral vectors for gene therapy is hindered by their lower transfection effi- ciency and their lacking of self-track ability. Experiments: This study aims to investigate the biological properties of halloysite nanotubes-carbon dots hybrid and its potential use as non-viral vector for oral gene therapy. The morphology and the chemical composition of the halloysite hybrid were investigated by means of high angle annular dark field scan- ning TEM and electron energy loss spectroscopy techniques, respectively. The cytotoxicity and the antioxidant activity were investigated by standard methods (MTS, DPPH and H2O2, respectively) using human cervical cancer HeLa cells as model. Studies of cellular uptake were carried out by fluorescence microscopy. Finally, we investigated the loading and release ability of the hybrid versus calf thymus DNA by fluorescence microscopy, circular dichroism, dynamic light scattering and f-potential measure- ments. Findings: All investigations performed confirmed the existence of strong electrostatic interactions between the DNA and the halloysite hybrid, so it shows promise as a multi-functional cationic non- viral vector that has also possesses intracellular tracking capability and promising in vitro antioxidant potential