Transmission Electron Microscopy-and Metabolomics-based Nanotoxicology Research

As nanotechnology develops, nanomaterials have been widely applied in daily life andsubsequent problem on the potential health risk are raised. This paper aims at providing methodsto mechanism studies in the field of nanotoxicology, and statistics for safety evaluation ofnanomaterial application. We investigated on the subcellular structure changes and metabolicchanges in L929cells after TiO2nanoparticles and polystyrene nanoparticles exposure usingtransmission electron microscope (TEM) and gas chromatograph with time-of-flight massspectrometry (GC/TOFMS)-based metabolomics approach. TEM outcomes showed that thedamage of subcellular structure got worse by the dosage and exposure time arose. And themeasurement of the damage extent was the vesicles and the mitochondria in L929cells. Also, thedosage effect is higher on the toxic effect of nanoparticles than the exposure time effect. In themetabolomics-based nanotoxicology study of TiO2nanoparticles, it was found that7metabolicpathways (impact-value>0.10) among the regulated pathways were significantly perturbed.12distinct amino acids are identified from these pathways. These results show that the disturbedamino acids played an important role in the TiO2nanoparticles-induced cytotoxicity. Along withearlier findings, we successfully used the metabolomics approaches to manifest TiO2nanoparticlesmight exhibit toxicity through triggering cellular oxidative stress, energy damage and theinhibition of DNA and RNA synthesis. In the metabolomics-based nanotoxicology study of PSnanoparticles,13metabolites with obvious concentration change were found in different dosagetreatment. And despite the dosage change, the toxicity of PS nanoparticles was induced throughdisturbance in carbohydrate metabolism and amino acid metabolism. Furthermore, the studyshowed the effectiveness of TEM and GC/TOFMS-based metabolomics approach innanotoxicology study.