Biological applications study of bio-nanocomposites based on chitosan/TiO nanoparticles polymeric films modified by oleic acid.

The aim of the present study was to prepare and characterize nanocomposite films to improve the treatment of skin wounds by applying the film as a bandage. To modify chitosan (Cs) and to prepare nanocomposites, a mixture between titanium dioxide nanoparticles (TiO NPs) was performed at different concentrations (2, 5, 10 and 15 wt%) and oleic acid (OA). The thin nanocomposite films were prepared by using casting method. The prepared films (Cs, Cs/TiO NPs, Cs/OA and Cs/OA/TiO NPs) were described by water absorption (swelling study) and biological degradation. Physico-chemical characterizations of Cs, Cs/OA, Cs/TiO NPs and Cs/OA/TiO NPs (with only 15 wt% TiO NPs) films were determined by X-ray diffraction, transmission high-resolution electron microscopy, field emission scanning electron microscopy, thermal analysis and Fourier transform infrared spectroscopy as well as their mechanical properties. Antimicrobial activity against microorganisms has been studied to assess activity against bacteria. The prepared nanocomposite films showed good antimicrobial activity for both Gram-positive and Gram-negative bacteria. The therapeutic effects of Cs-TiO NPs-oleic acid nanocomposites on healing excision wounds were studied in rat animal model. The data obtained revealed that groups treated with nanocomposites showed enhancement wound closure and speed up wound healing time.