In recent years, silver nanoparticles have found broad application as antibacterial agents in products ranging from medical devices to high-tech clothing. A team led by Huan-Tsung Chang of National Taiwan University investigates the use of tellurium nanoparticles as antibacterial agents displaying high activity and low toxicity.

The reseachers prepared tellurium nanoparticles by reducing TeO₂ with hydrazine. Depending on the concentration of reagents and the temperature, particles shaped like cubes, grains of rice, pencils, and wires were obtained. Under physiological conditions, the nanoparticles were found to slowly release TeO₃^2– ions, which were taken up by Escherichia coli bacteria, eventually leading to their death. The nanoparticles with lower aspect ratios (cubes, rice) were more potent antibacterials, killing 85 % of bacteria when applied at a concentration of 10 μg mL^–1, compared to 70 % of bacteria that were killed with the nanopencils and nanowires.

The tellurium nanoparticles were also shown to be less toxic than sodium tellurite and silver nanoparticles, making them attractive for future applications as antibacterial agents.

• Antibacterial Activities of Tellurium Nanomaterials,
  Z.-H. Lin, C.-H. Lee, H.-Y. Chang, H.-T. Chang,
  Chem. Asian J. 2012.
  DOI: 10.1002/asia.201101006