Biodistribution of pristine single-walled carbon nanotubes in vivo

The biodistribution of pristine single-walled carbon nanotubes (SWNTs) in mice was determined by using the skeleton C-13-enriched SWNTs and isotope ratio mass spectroscopy. The results suggested that the SWNTs were distributed in the entire body, with major accumulations in the liver, lungs, and spleen over an extended period of time. The specimen from the effected organ tissues were examined by using transmission electron microscopy, aimed toward an understanding of the possible uptake mechanism. The biological consequence of pristine SWNTs is obviously very different from that of their chemically modified or functionalized counterparts. The implication of such a fact is discussed.