Hani A. Alhadrami^{1, 2}, Aisha Baqasi¹, Javed Iqbal³, Raniyah A.M. Shoudri¹, Ahmad Mohammad Ashshi⁴, Esam I. Azhar^{1, 5}, Faten Al-Hazmi⁶, Ahmed Al-Ghamdi⁶, S. Wageh^{6, 7,}

Many methods have been used for the preparation of nanostructured metal oxides. Here we report the synthesis of TiO₂ nanoparticles by facile hydrothermal process by varying the concentration of the precursor and reaction temperature while keeping the process time constant. Morphological, structural and optical studies were carried out by scanning electron microscopy equipped with energy dispersive spectroscopy, X-ray powder diffraction spectroscopy and VU-Vis-NIR spectroscopy. Morphological and compositional analysis reveal that the prepared nanoparticles are highly pure with an approximate average particle size 5-15nm. XRD studies showed their crystalline structure and the sizes around 5 nm, while the optical absorption studies in the photon wavelength range 300-600 nm reveal that the strong absorbance peak is positioned at around 3.5 eV nm whereas visible energy is almost transparent for the materials. Finally, the antibacterial effect of TiO₂ nanoparticles has been studied. Plating technique was used to determine lowest concentration that prevent or inhibit growth of bacteria. This technique of TiO₂ nanoparticle was used against most common organisms which cause wound infection including: MRSA, E. coli and Pseudomonas aeruginosa. Different concentrations of TiO₂ nanoparticles were used 100 μg/ml, 200 μg/ml, 400 μg/ml, 600 μg/ml and 800 μg/ml. Inhibition of bacteria was different for prepared TiO₂ samples due to different concentration of the precursors and synthesis temperature.

TiO₂, nanoparticles, crystal structure, antibacterial