Nanowerk‘s Michael Berger has filed a report about a breakthrough technology developed by Dr. R. Bruce Weisman and colleagues at Rice University to detect the presence of single-walled carbon nanotubes (SWCNTs) inside living cells via NIR fluorescence. Such research might help investigators to further delineate the role SWCNTs play on intracellular biochemistry:
Nanotechnology’s poster child, the carbon nanotube (CNT), has been explored for use in many technical applications. Increasingly, researchers are also looking at the unique biological properties of CNTs for potential biomedical uses. For instance, the interaction between DNA and CNTs have been explored and DNA-functionalized nanotubes hold significant promise as nucleic acid sensors. Nanotubes have also been considered for use as scaffolds for cells in tissue engineering. No matter what their intended function, any material used in medicine must exhibit – among other compatibility factors – biocompatibility, non-toxicity and non-carcinogenicity. And here the jury is still out as far as CNTs are concerned. One limiting factor of toxicological studies so far has been the use of animal tissue rather than living specimen. Researchers have now succeeded in detecting single-walled CNTs (SWCNTs) inside living animals – with surprisingly benign results – paving the way for future research on the effects and fate of nanotubes inside living organisms.
“We believe that our work is the first observation of carbon nanotubes in a living animal and the first detection of individual nanotubes in biological tissues” Dr. R. Bruce Weisman explains to Nanowerk. “Although much more work must be done to investigate the effects of SWCNT exposure on higher animals (mammals), these results show an absence of negative effects in one system and suggest that it is worthwhile to continue studying SWCNTs for biomedical applications, including diagnostic imaging based on their unique near-IR fluorescence signatures.”
Weisman, a professor in the Department of Chemistry at Rice University in Houston, Texas, and his group investigate the spectroscopy and photophysics of fullerenes and carbon nanotubes. Following the discovery in Weisman’s lab of near-infrared nanotube fluorescence, the group has measured and unraveled the absorption and emission spectra of more than 30 semiconducting nanotube species. In his most recent work, Weisman, together with co-author Kathleen Beckingham, professor of biochemistry and cell biology, attempted the first-ever detection of nanotubes inside a living animal. Their findings have been published in a recent paper in Nano Letters (“Single-Walled Carbon Nanotubes in the Intact Organism: Near-IR Imaging and Biocompatibility Studies in Drosophila”).