Nanostructured TiO2 Prepared Through Solâ€“Gel Method Enhances the Activity of Antibiotics against Gram Positive Bacteria

durga prasad; Nagaraju Kottam; H. Nagabhushana; C.R. Girija; T.V. Venkatesha; B.M. Nagabhushana

Abstract

The synthesis and bioactivity of titanium dioxide (TiO2) nanoparticles has been extensively studied. However, the antibacterial activity of TiO2 individually or in combination with different antibiotics has not been demonstrated. TiO2 was prepared by sol–gel process using precursor Titanium (IV) Chloride (TiCl4) and concentrated sulfuric acid in 4 h of calcinations at 550 °C and the enhancement effect of TiO2 nanoparticle on the antibacterial activity of different antibiotics was evaluated against gram positive bacteria (Staphylococcus aureus). Disk diffusion method was used to determine the antibacterial activity of various classes of antibiotics in the absence and presence of sub inhibitory concentration of TiO2 nanoparticles. A clinical isolate of S. aureus was used as the test strain. In the presence of sub-inhibitory concentration of TiO2 nanoparticles (25μg/disc) the antibacterial activities of all antibiotics have increased from minimum 2 mm to a maximum of 10 mm. The highest increase was observed for Ampicillin and Amikacin. These results signify that the TiO2 nano particles potentiate the antimicrobial action of beta lactums, cephalosporins, amino glycosides, glycopeptides, macrolids and lincosamides, tetracycline, suggesting a possible utilization of nano compounds in combination therapy against gram positive bacteria. Keywords: Antibiotics, sol–gel, nano-materials, antibacterial activity, titanium oxide