Biocompatible nanoscale dispersion of single-walled carbon nanotubes minimizes in vivo pulmonary toxicity.
Excitement surrounding the attractive physical and chemical characteristics of single walled carbon nanotubes (SWCNTs) has been tempered by concerns regarding their potential health risks. Here we consider the lung toxicity of nanoscale dispersed SWCNTs (mean diameter approximately 1 nm). Because dispersion of the SWCNTs increases their aspect ratio relative to as-produced aggregates, we directly test the prevailing hypothesis that lung toxicity associated with SWCNTs compared with other carbon structures is attributable to the large aspect ratio of the individual particles. Thirty days after their intratracheal administration to mice, the granuloma-like structures with mild fibrosis in the large airways observed in mice treated with aggregated SWCNTs were absent in mice treated with nanoscale dispersed SWCNTs. Examination of lung sections from mice treated with nanoscale dispersed SWCNTs revealed uptake of the SWCNTs by macrophages and gradual clearance over time. We conclude that the toxicity of SWCNTs in vivo is attributable to aggregation of the nanomaterial rather than the large aspect ratio of the individual nanotubes. Biocompatible nanoscale dispersion provides a scalable method to generate purified preparations of SWCNTs with minimal toxicity, thus allowing them to be used safely in commercial and biomedical applications.
Mutlu
Gökhan M
GM
Department of Medicine, Division of Pulmonary and Critical Care Medicine, Northwestern University Feinberg School of Medicine, Evanston, IL 60208, USA.
Budinger
G R Scott
GR
Green
Alexander A
AA
Urich
Daniela
D
Soberanes
Saul
S
Chiarella
Sergio E
SE
Alheid
George F
GF
McCrimmon
Donald R
DR
Szleifer
Igal
I
Hersam
Mark C
MC
D000818:Animals; D001672:Biocompatible Materials / Q000633:toxicity*; D003102:Colloids / Q000737:chemistry / Q000633:toxicity; D003460:Crystallization / Q000379:methods; D008422:Materials Testing; D051379:Mice; D008810:Mice, Inbred C57BL; D043942:Nanotubes / Q000737:chemistry* / Q000633:toxicity* / Q000648:ultrastructure; D010316:Particle Size; D014132:Trachea / Q000187:drug effects* / Q000473:pathology*; D014136:Tracheitis / Q000139:chemically induced* / Q000473:pathology*
D001672:Biocompatible Materials; D003102:Colloids