Synthesis of “Naked” TeO(2) Nanoparticles for Biomedical Applications

[Image: see text] Chalcogenide nanoparticles have become a very active field of research for their optoelectronic and biological properties. This article shows the production of tellurium dioxide nanoparticles (TeO(2) NPs) by pulsed laser ablation in liquids. The produced nanoparticles were spherical with a diameter of around 70 nm. The energy band gap of those nanoparticles was determined to be around 5.2 eV. Moreover, TeO(2) NPs displayed a dose-dependent antibacterial effect against antibiotic-resistant bacteria such as multidrug-resistant Escherichia coli (MDR E. coli) and methicillin-resistant Staphylococcus aureus (MR S. aureus). The “naked” nature of the nanoparticle surface helped to eradicate the antibiotic-resistant bacteria at a very low concentration, with IC50 values of ∼4.3 ± 0.9 and 3.7 ± 0.2 ppm for MDR E. coli and MR S. aureus, respectively, after just 8 h of culture. Further, the IC50 values of the naked TeO(2) NPs against melanoma (skin cancer) and healthy fibroblasts were 1.6 ± 0.7 and 5.5 ± 0.2 ppm, respectively, for up to 72 h. Finally, to understand these optimal antibacterial and anticancer properties of the TeO(2) NPs, the reactive oxygen species generated by the nanoparticles were measured. In summary, the present in vitro results demonstrate much promise for the presently prepared TeO(2) NPs and they should be studied for a wide range of safe antibacterial and anticancer applications.