THE ANTIBACTERIAL ACTIVITY OF TIO2 NANOPARTICLES PREPARED BY SOL-GEL METHOD FOR A GROUP OF GRAM-POSITIVE AND NEGATIVE BACTERIA

Abstract

Titanium dioxide nanoparticles TiO₂ NP were prepared by sol-gel method. TiO₂ NP was identified and characterized using scanning electron microscopy (SEM), ultraviolet spectroscopy (UV-vis), Fourier transform infrared (FTIR), X-ray diffraction ( XRD) and atomic force microscopy (AFM). The SEM results showed an irregular spherical shape with different diameters (22.84-65.98) nm. The highest UV-Vis absorption was recorded at 345 nm wavelength. FTIR was used to find out the effective aggregates and the success of the process of forming TiO₂ NP bands. The first centered between (450 – 800 cm-1), which is attributed to the patterns of stretching vibrations of the titanium oxide bond (Ti-O Vibrations). While the XRD peaks appeared at angles 2Ѳ (27.32°, 35.89° 39.03°, 41.02°, 43.88°, 54.09°, 56.38°, 62.43°, 63.77°, 68.67°, 69.41°, 76.11°) at Crystal Planes (110) (101) (200) (111) (210) (211) ( (220) (002) (310) (301) (112) and (202), (respectively, which corresponds to JCPDS standard tables), and this indicates the formation of rutile-type NPs TiO₂. The results of (AFM) ranged between (6-7 nm) and the mean height (Z-mean value) was (8 nm). The effectiveness of NP TiO₂ was tested at different concentrations (1, 0.75,0.5) mg/ml against a group of Gram-negative and Gram-positive bacteria:(Pseudomonas aeruginosa, Salmonella typhimurium, Bacillus subtilis, Staphylococcus aureus, E.coli) reached the highest zone of inhibition at a concentration of (1) mg/ml for Staphylococcus aureus, as the diameter of inhibition was (19.5).