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Cellular Toxicity of Carbon - based Nanomaterials. Nano Letters, 2006, 6 (6), pp 1121–1125. Arnaud Magrez, Sandor Kasas, Valérie Salicio, Nathalie Pasquier, Jin Won Seo, Marco Celio, Stefan Catsicas, Beat Schwaller, and László Forró. Jaehyun Park EE235 Student Presentation 2 May 4, 2009.
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Cellular Toxicity of Carbon-based Nanomaterials Nano Letters, 2006, 6 (6), pp 1121–1125 Arnaud Magrez, Sandor Kasas, Valérie Salicio, Nathalie Pasquier, Jin Won Seo, Marco Celio, Stefan Catsicas, Beat Schwaller, and László Forró Jaehyun Park EE235 Student Presentation 2 May 4, 2009 Electrical Engineering and Computer Sciences University of California, Berkeley
Backgrounds Discovery of Numerous Nanomaterials • CBNs (Carbon-based nanomaterials) such as carbon nanotubes / carbon fibers / carbon nanoparticles • One of key elements in nanotechnology CBNs in Biological Applications • Recently attracted much attention to DNA / proteins / drug delivery • Lack of information concerning the potential hazards to CBN exposure In Vitro Toxicity of CBNs on Lung Cells • Lung : directly exposed after inhalation of contaminated air – One of the first target organs of nanomaterials – Nanomaterials distribute in the whole respiratory tract To provide Information about Biocompatibility of Nanomaterials for in vitro research
+ Carbon black + MWCNTs + CNFs Effect of CBNs on Cell Toxicity • Various aspect ratios of CBNs • MWCNTs (AR : 80-90) CNFs (AR : 30-40) Carbon black (AR : 1) • Diluted in gelatin solution to avoid aggregation with 0.02µg/mL and 0.2 µg/mL Proliferation Curve for 3 Different Lung Tumor Cells • Optical density ~ Number of cells • Shows similar behavior • Two controls > Low concentration > • High concentration • H446 + CNFs showed the highest sensitivity and reproducibility
Toxicity appeared within 1 day Differences more pronounced for 5 days Proliferation for H446 Cells with CBNs Toxicity of various CBNs Dose-dependent toxicity • Toxicity ~ CBN dose • Toxicity : Aspect ratio dependent • Carbon black > CNFs > MWCNTs : Filaments were less toxic than particles
Morphological Change Control With 0.02µg/mL of MWCNT • Close cell-cell contacts • Polygonal-shaped • Lost mutual attachments • Smaller & condensed nuclei • Cytoplasm retracted • CBNs caused typical irreversible cell injuries and cell death • No specific morphological differences w.r.t. different CBNs
Another Paper Supports Toxicity Dose-Dependent Toxicity of CNTs in Alveolar Macrophage (AM) • Toxicity : SWNTs > MWNT > Fullerenes (C60) Jia el al., Cytotoxicity of carbon nanomaterials: single-wall nanotube, multi-wall nanotube, and fullerene, Environ. Sci. Technol.39 (2005), pp. 1378–1383.
Summary / Conclusion • Nanomaterials MAY affect Toxicity of Cells • Depends on aspect ratio : Filaments were less toxic than particles • Depends on concentration : Higher concentration more toxic • Toxicity : Still Debating • Some papers showed no clear correlation between the biological impact of nanomaterials and their properties such as size, surface structure, crystalline phase, chemical composition, presence of metal trace impurities • – Soto et al., Acta Biomaterialia, 2007 / Pulskamp et al., Tox. Letters, 2007etc • Every condition leads to a different biological response • Different cell type would have different behavior • Nanomaterialsnot always fully characterized before and during the experiment • Conclusion • More research needed to get more information • Cell viability should be investigated carefully when the integration is needed