Determination of F₂-isoprostanes in Cultured Human Lung Epithelial Cells after Exposure to Metal Oxide and Silica Nanoparticles by High-Performance Liquid Chromatography/Tandem Mass Spectrometry

The environmental impact of nanotechnology has caused a great concern. Many in vitro studies showed that many types of nanoparticles were cytotoxic. However, whether these nanoparticles caused cell membrane damage was not well studied. F ₂ -isoprostanes are specific products of arachidonic acid peroxidation by nonenzymatic reactive oxygen species and are considered as reliable biomarkers of oxidative stress and lipid peroxidation. In this article, we investigated the cytotoxicity of different nanoparticles and the degree of cellular membrane damage by using F ₂ -isoprostanes as biomarkers after exposure to nanoparticles. The human lung epithelial cell line A549 was exposed to four silica and metal oxide nanoparticles: SiO ₂ (15 nm), CeO ₂ (20 nm), Fe ₂ O ₃ (30 nm), and ZnO (70 nm). The levels of F ₂ -isoprostanes were determined by using highperformance liquid chromatography/mass spectrometry. The F ₂ -isoprostanes' peak was identified by retention time and molecular ion m/z at 353. Oasis HLB cartridge was used to extract F ₂ -isoprostanes from cell medium. The results showed that SiO ₂ , CeO ₂ , and ZnO nanoparticles increased F ₂ -isoprostanes levels significantly in A549 cells. Fe ₂ O ₃ nanoparticle also increased F ₂ -isoprostanes level, but was not significant. This implied that SiO ₂ , CeO ₂ , ZnO, and Fe ₂ O ₃ nanoparticles can cause cell membrane damage due to the lipid peroxidation. To the best of our knowledge, this is the first report on the investigation of effects of cellular exposure to metal oxide and silica nanoparticles on the cellular F ₂ -isoprostanes levels.