Synthesis and characterization of chitosan-coated titanate nanotubes: towards a new safe nanocarrier

In this work, we discuss for the first time the elaboration of nanohybrid materials, intended for drug delivery systems, based on titanate nanotubes (TiONts) coated with chitosan polymer (CT). Chitosan has been used to enhance the biocompatibility of hydrothermally synthesized nanotubes in biological medium as a substitute for the polyethylene glycol (PEG) that is generally used for biocompatibility. CT grafting was carried out using two different approaches; the first was made by a covalent bond using two intermediate molecules, and the second is based on electrostatic interactions between CT and TiONts. The type of elaborated bond on the surface of TiONts was proven to influence the colloidal stability of the elaborated nanohybrids, which were studied in different media. A detailed comparison between these two approaches was carried by XPS and TGA-SM techniques. Finally, an original and sensitive cytotoxicity assay consisting of the measurement of the cells' total RNA synthesis was used to prove the non-toxicity of both obtained nanohybrids.