Effects of Brookite TiO₂/CeO₂ Nanocomposite on <i>Artemia salina</i>: Induction of Oxidative Stress and Apoptosis Assessment

Abstract

TiO2 and CeO2 NPs are widely used in the medical field, for drug administration, oncological therapies, disinfection or diagnostic imaging. To date, their effects on aquatic ecosystems and their impacts on human health are little known but several scientific evidences show how CeO2 NPs are able to store and release oxygen, giving them antioxidant activity against oxidative stress while TiO2 NPs seem to be responsible for cytotoxicity and genotoxicity. In this study, the effects of combined nanoparticles, brookite TiO2/CeO2 nanocomposites, on A. salina nauplii following acute exposure were evaluated. Although the cytotoxicity of nanoparticles is generally dose-dependent and time-dependent, in the following investigation, exposure to combined nanoparticles, brookite TiO2/CeO2 nanocomposites, in A. salina nauplii would appear not to have had a statistically significant negative impact on the viability of the specimens. One of the mechanisms by which NPs exert toxic effects is the induction of oxidative stress. In this study, an assessment of potential oxidative stress and apoptotic damage on exposed organisms was conducted through the use of the DCFH2DA probe and acridine orange. The results obtained suggest that although acute exposure to different concentrations of brookite TiO2/CeO2 nanocomposites did not have lethal effects, the positivity to DCFH2DA and acridine orange observed does not exclude potential sublethal effects.

Keywords

• nauplii
• toxicological assay
• oxidative stress