Journal of Nanoparticle Research

, Volume 9, Issue 1, pp 85–92

Measuring particle size-dependent physicochemical structure in airborne single walled carbon nanotube agglomerates

  • Andrew D. Maynard
  • Bon Ki Ku
  • Mark Emery
  • Mark Stolzenburg
  • Peter H. McMurry
Article

Abstract

As-produced single-walled carbon nanotube (SWCNT) material is a complex matrix of carbon nanotubes, bundles of nanotubes (nanoropes), non-tubular carbon and metal catalyst nanoparticles. The pulmonary toxicity of material released during manufacture and handling will depend on the partitioning and arrangement of these components within airborne particles. To probe the physicochemical structure of airborne SWCNT aggregates, a new technique was developed and applied to aerosolized as-produced material. Differential Mobility Analysis-classified aggregates were analyzed using an Aerosol Particle Mass Monitor, and a structural parameter Γ (proportional to the square of particle mobility diameter, divided by APM voltage) derived. Using information on the constituent components of the SWCNT, modal values of Γ were estimated for specific particle compositions and structures, and compared against measured values. Measured modal values of Γ for 150 nm mobility diameter aggregates suggested they were primarily composed of non-tubular carbon from one batch of material, and thin nanoropes from a second batch of material – these findings were confirmed using Transmission Electron Microscopy. Measured modal values of Γ for 31 nm mobility diameter aggregates indicated that they were comprised predominantly of thin carbon nanoropes with associated nanometer-diameter metal catalyst particles; there was no indication that either catalyst particles or non-tubular carbon particles were being preferentially released into the air. These results indicate that the physicochemistry of aerosol particles released while handling as-produced SWCNT may vary significantly by particle size and production batch, and that evaluations of potential health hazards need to account for this.

Keywords

aerosol carbon nanotubes differential mobility analysis aerosol particle mass monitor composite nanoparticles occupational health 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Bronikowski M.J., Willis P.A., Colbert D.T., Smith K.A., Smalley R.E. (2001). Gas-phase production of carbon single-walled nanotubes from carbon monoxide via the HiPCO® process: A parametric study. J. Vac. Sci. Technol. A.-Vac. Surf. Films 19(4): 1800–1805CrossRefGoogle Scholar
  2. Ehara K., Hagwood C., Coakley K.J. (1996). Novel method to classify aerosol particles according to their mass-to-charge ratio – aerosol particle mass analyzer. J. Aerosol Sci. 27(2): 217–234CrossRefGoogle Scholar
  3. Keller A., Fierz M., Siegmann K., Siegmann H.C., Filippov A. (2001). Surface science with nanosized particles in a carrier gas. J. Vacuum Sci. Technol. Vacuum Surf. Films 19(1): 1–8CrossRefGoogle Scholar
  4. Knutson E.O., Whitby K.T. (1975). Aerosol classification by electrical mobility: Apparatus, theory, and applications. J. Aerosol Sci. 6: 443–451CrossRefGoogle Scholar
  5. Ku B.K., Maynard A.D. (2005). Comparing aerosol surface-area measurement of monodisperse ultrafine silver agglomerates using mobility analysis, transmission electron microscopy and diffusion charging. J. Aerosol Sci. 36(9): 1108–1124CrossRefGoogle Scholar
  6. Lam C.-W., James J.T., McCluskey R., Hunter R.L. (2004). Pulmonary toxicity of single-wall carbon nanotubes in mice 7 and 90 days after intratracheal instillation. Toxicol. Sci. 77: 126–134CrossRefGoogle Scholar
  7. Maynard A.D. (1995). The development of a new thermophoretic precipitator for scanning-transmission electron-microscope analysis of ultrafine aerosol-particles. Aerosol Sci. Technol. 23(4): 521–533Google Scholar
  8. Maynard A.D., Baron P.A., Foley M., Shvedova A.A., Kisin E.R., Castranova V. (2004). Exposure to carbon nanotube material: Aerosol release during the handling of unrefined single walled carbon nanotube material. J. Toxicol. Environ. Health 67(1): 87–107Google Scholar
  9. McMurry P.H., Wang X., Park K., Ehara K. (2002). The relationship between mass and mobility for atmospheric particles: A new technique for measuring particle density. Aerosol Sci. Technol. 36(2): 227–238CrossRefGoogle Scholar
  10. Oberdörster G., A. Maynard, K. Donaldson, V. Castranova, J. Fitzpatrick, K. Ausman, J. Carter, B. Karn, W. Kreyling, D. Lai, S. Olin, N. Monteiro-Riviere, D. Warheit & H. Yang, 2005. Principles for characterizing the potential human health effects from exposure to nanomaterials: elements of a screening strategy. Part. Fiber Toxicol. 2(8): doi:10.1186/1743-8977-2-8Google Scholar
  11. Park K., Kittelson D.B., McMurry P.H. (2004a). Structural properties of diesel exhaust particles measured by transmission electron microscopy (TEM): Relationships to particle mass and mobility. Aerosol Sci. Tech. 38(9): 881–889CrossRefGoogle Scholar
  12. Park K., Kittelson D.B., Zachariah M.R., McMurry P.H. (2004b). Measurement of inherent material density of nanoparticle agglomerates. J. Nanopart. Res. 62(2): 267–272CrossRefGoogle Scholar
  13. Rogak S.N., Flagan R.C., Nguyen H.V. (1993). The mobility and structure of aerosol agglomerates. Aerosol Sci. Technol. 18(1): 25–47Google Scholar
  14. Shvedova A.A., Kisin E.R., Mercer R., Murray A.R., Johnson V.J., Potapovich A.I., Tyurina Y.Y., Gorelik O., Arepalli S., Schwegler-Berry D., Hubbs A.F., Antonini J., Evans D.E., Ku B.K., Ramsey D., Maynard A., Kagan V.E., Castranova V., Baron P. (2005). Unusual inflammatory and fibrogenic pulmonary responses to single-walled carbon nanotubes in mice. Am. J. Physiol.-Lung Cell. Mol. Physiol. 289: 698–708CrossRefGoogle Scholar
  15. Shvedova A.A., Kisin E.R., Murray A.R., Gandelsman V.Z., Maynard A.D., Baron P.A., Castranova V. (2003). Exposure to carbon nanotube material: Assessment of the biological effects of nanotube materials using human keratinocyte cells. J. Toxicol. Environ. Health 66(20): 1909–1926Google Scholar
  16. Warheit D.B., Laurence B.R., Reed K.L., Roach D.H., Reynolds G.A.M., Webb T.R. (2004). Comparative pulmonary toxicity assessment of single-wall carbon nanotubes in rats. Toxicol. Sci. 77: 117–125CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • Andrew D. Maynard
    • 1
  • Bon Ki Ku
    • 2
  • Mark Emery
    • 3
  • Mark Stolzenburg
    • 3
  • Peter H. McMurry
    • 3
  1. 1.Woodrow Wilson International Center for ScholarsProject on Emerging NanotechnologiesWashingtonUSA
  2. 2.Centers for Disease Control and PreventionNational Institute for Occupational Safety and HealthCincinnatiUSA
  3. 3.Mechanical Engineering DepartmentUniversity of MinnesotaMinneapolisUSA

Personalised recommendations