title: Biocompatibility and toxicological studies of carbon nanotubes doped with nitrogen.
abstract: In this report, we compare the toxicological effects between pure carbon multiwalled nanotubes (MWNTs) and N-doped multiwalled carbon (CNx) nanotubes. Different doses of tubes were administered in various ways to mice: nasal, oral, intratracheal, and intraperitoneal. We have found that when MWNTs were injected into the mice's trachea, the mice could die by dyspnea depending on the MWNTs doses. However, CNx nanotubes never caused the death of any mouse. We always found that CNx nanotubes were far more tolerated by the mice when compared to MWNTs. Extremely high concentrations of CNx nanotubes administrated directly into the mice's trachea only induced granulomatous inflammatory responses. Importantly, all other routes of administration did not induce signs of distress or tissue changes on any treated mouse. We therefore believe that CNx nanotubes are less harmful than MWNTs or SWNTs and might be more advantageous for bioapplications.
authors.affiliation: Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Cd. Universitaria, 04510, México.
authors.forename: J C
authors.initials: JC
authors.lastname: Carrero-Sanchez
authors.forename: A L
authors.initials: AL
authors.lastname: Elías
authors.forename: R
authors.initials: R
authors.lastname: Mancilla
authors.forename: G
authors.initials: G
authors.lastname: Arrellín
authors.forename: H
authors.initials: H
authors.lastname: Terrones
authors.forename: J P
authors.initials: JP
authors.lastname: Laclette
authors.forename: M
authors.initials: M
authors.lastname: Terrones
mesh_terms: D000280:Administration, Inhalation; D000818:Animals; D001672:Biocompatible Materials / Q000008:administration & dosage* / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D005549:Foreign-Body Reaction / Q000209:etiology* / Q000473:pathology*; D007267:Injections; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D037742:Nanotubes, Carbon / Q000633:toxicity*; D009584:Nitrogen / Q000008:administration & dosage* / Q000633:toxicity*; D015996:Survival Rate
chemical_list: D001672:Biocompatible Materials; D037742:Nanotubes, Carbon; D009584:Nitrogen