Optimisation of preparation conditions for Ti nanowires and suitability as an antibacterial material

Ultrafine titanium dioxide (TiO₂) nanowires were synthesised using a hydrothermal method with different volumes of ethylene glycol (EG) and annealing temperatures. It shows that sodium titanate nanowires synthesised using 5 and 10 ml EG, which annealed at 400°C produced TiO₂ nanowires that correspond to a photochemically active phase, which is anatase. The influences of annealing temperatures (400-600°C) on the morphological arrangement of TiO₂ nanowires were evident in the field emission scanning electron microscopy. The annealing temperature of 500°C led to agglomeration, which formed a mixture of TiO₂ nanoparticles and nanowires. High thermal stability of TiO₂ nanowires revealed by thermogravimetric analysis and Fourier transform infrared spectroscopy spectrum showed the presence of the Ti-O-Ti vibrations as evidenced due to TiO₂ lattices. An antibacterial study using TiO₂ nanowires toward Escherichia coli and Klebsiella pneumoniae showed large zones of inhibition that indicated susceptibility of the microbe toward TiO₂. Growth kinetic analysis shows that addition of TiO₂ has reduced optical density (OD) suggesting an inhibition of the growth of bacteria. These results indicate TiO₂ nanowires can be effectively used as an antimicrobial agent against gram-bacteria. The TiO₂ nanowires could be exploited in the medical, packaging and detergent formulation industries and wastewater treatment.