Mammalian pharmacokinetics of carbon nanotubes using intrinsic near-infrared fluorescence
- Paul Cherukuri*,
- Christopher J. Gannon†,
- Tonya K. Leeuw*,
- Howard K. Schmidt*,
- Richard E. Smalley*,‡,
- Steven A. Curley†, and
- R. Bruce Weisman*,§
- *Department of Chemistry, Carbon Nanotechnology Laboratory, Smalley Institute for Nanoscale Science and Technology, and Center for Biological and Environmental Nanotechnology, Rice University, 6100 Main Street, Houston, TX 77005; and
- †Department of Surgical Oncology, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030
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Communicated by Robert F. Curl, Rice University, Houston, TX, October 20, 2006 (received for review July 31, 2006)
Abstract
Individualized, chemically pristine single-walled carbon nanotubes have been intravenously administered to rabbits and monitored through their characteristic near-infrared fluorescence. Spectra indicated that blood proteins displaced the nanotube coating of synthetic surfactant molecules within seconds. The nanotube concentration in the blood serum decreased exponentially with a half-life of 1.0 ± 0.1 h. No adverse effects from low-level nanotube exposure could be detected from behavior or pathological examination. At 24 h after i.v. administration, significant concentrations of nanotubes were found only in the liver. These results demonstrate that debundled single-walled carbon nanotubes are high-contrast near-infrared fluorophores that can be sensitively and selectively tracked in mammalian tissues using optical methods. In addition, the absence of acute toxicity and promising circulation persistence suggest the potential of carbon nanotubes in future pharmaceutical applications.
Footnotes
- §To whom correspondence should be addressed. E-mail: weisman{at}rice.edu
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↵ ‡Deceased October 28, 2005.
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Author contributions: P.C., H.K.S., R.E.S., S.A.C., and R.B.W. designed research; P.C., C.J.G., and T.K.L. performed research; P.C., C.J.G., T.K.L., S.A.C., and R.B.W. analyzed data; and R.B.W. wrote the paper.
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Conflict of interest statement: R.B.W. holds an interest in Applied NanoFluorescence, LLC.
- Abbreviation:
- SWNT,
- single-walled carbon nanotubes.
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Freely available online through the PNAS open access option.
- © 2006 by The National Academy of Sciences of the USA
