title: Biodistribution of Carbon Nanotubes in Animal Models.
abstract: The many interesting physical and chemical properties of carbon nanotubes (CNT) make it one of the most commercially attractive materials in the era of nanotechnology. Here, we review the recent publications on in vivo biodistribution of pristine and functionalized forms of single-walled and multi-walled CNT. Pristine CNT remain in the lung for months or even years after pulmonary deposition. If cleared, the majority of CNT move to the gastrointestinal (GI) tract via the mucociliary escalator. However, there appears to be no uptake of CNT from the GI tract, with a possible exception of the smallest functionalized SWCNT. Importantly, a significant fraction of CNT translocate from the alveolar space to the near pulmonary region including lymph nodes, subpleura and pleura (<7% of the pulmonary deposited dose) and to distal organs including liver, spleen and bone marrow (~1%). These results clearly demonstrate the main sites of long-term CNT accumulation, which also includes pleura, a major site for fibre-induced pulmonary diseases. Studies on intravenous injection show that CNT in blood circulation are cleared relatively fast with a half-life of minutes or hours. The major target organs were the same as identified after pulmonary exposure with the exception of urine excretion of especially functionalized SWCNT and accumulation in lung tissue. Overall, there is evidence that CNT will primarily be distributed to the liver where they appear to be present at least one year after exposure.
authors.affiliation: The National Research Centre for the Working Environment, Copenhagen, Denmark.
authors.forename: Nicklas Raun
authors.initials: NR
authors.lastname: Jacobsen
authors.affiliation: Department of Public Health, Section of Environmental Health, University of Copenhagen, Copenhagen K, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Møller
authors.affiliation: The National Research Centre for the Working Environment, Copenhagen, Denmark.
authors.forename: Per Axel
authors.initials: PA
authors.lastname: Clausen
authors.affiliation: The National Research Centre for the Working Environment, Copenhagen, Denmark.
authors.forename: Anne Thoustrup
authors.initials: AT
authors.lastname: Saber
authors.affiliation: ECAMRICERT, Vicenza, Italy.
authors.forename: Christian
authors.initials: C
authors.lastname: Micheletti
authors.affiliation: The National Research Centre for the Working Environment, Copenhagen, Denmark.
authors.forename: Keld Alstrup
authors.initials: KA
authors.lastname: Jensen
authors.affiliation: The National Research Centre for the Working Environment, Copenhagen, Denmark.|Department of Public Health, Section of Environmental Health, University of Copenhagen, Copenhagen K, Denmark.
authors.forename: Håkan
authors.initials: H
authors.lastname: Wallin
authors.affiliation: The National Research Centre for the Working Environment, Copenhagen, Denmark.|Department of Micro and Nanotechnology, Technical University of Denmark, Lyngby, Denmark.
authors.forename: Ulla
authors.initials: U
authors.lastname: Vogel
mesh_terms: D000818:Animals; D004337:Drug Carriers / Q000032:analysis / Q000737:chemistry / Q000633:toxicity; D065569:Gastrointestinal Absorption; D041981:Gastrointestinal Tract / Q000737:chemistry* / Q000378:metabolism / Q000473:pathology; D006207:Half-Life; D006801:Humans; D019570:Inhalation Exposure; D008168:Lung / Q000737:chemistry* / Q000473:pathology; D008198:Lymph Nodes / Q000737:chemistry* / Q000473:pathology; D023421:Models, Animal; D037742:Nanotubes, Carbon / Q000032:analysis / Q000737:chemistry / Q000633:toxicity*; D065667:Renal Elimination; D014018:Tissue Distribution
chemical_list: D004337:Drug Carriers; D037742:Nanotubes, Carbon