Comprehensive Study on The Bio-safety of Single-walled Carbon Nanotubes

Single-walled carbon nanotubes were oxidized and the XRD spectra of o-SWNTs indicated that there are no residual catalysts existed. Then four popular cell viability assays were used to investigate the cytotoxicity of o-SWNTs to K562 cells. The concentrations of o-SWNTs used to treat cells were varied from 5 to 50 μg/mL, and it was found that o-SWNTs have no influences on cell viability. In order to acquire a comprehensive understanding on the bio-safety of o-SWNTs, online 2-D nano-LC/MS/MS identification and semi-quantitative proteomic analysis were conducted. Semiquantitative analysis suggested that 33 proteins were notably changed during the treatment with o-SWNTs. Among them, 18 proteins were significantly up-regulated, and 15 were down-regulated. As noted by Gene Ontology annotation, the identified proteins demonstrate a wide range of biological processes, such as cell cycle, cell death, cell communication, response to stimulus, metabolism and so on. Especially, an important protein related with the transportation of oxygen, Hemoglobin alpha subunit, has significant change, nearly 9-folds higher in K562 cells after treatment with o-SWNTs