Authors: S. Bellucci, C. Balasubramanian, A. Bergamaschi, M. Bottini, A. Magrini and T. Mustelin
Affilation: INFN-Laboratori Nazionali di Frascati, Italy
Pages: 217 - 220
Keywords: carbon nanotubes, composite materials, biosensors, cytotoxicity
Carbon nanotubes, a form of carbon that did not exist in our environment before being manufactured possess unique chemical, physical, optical, and magnetic properties, which make them suitable for many uses in industrial products and in the field of nanotechnology, including nanomedicine. Hence, it is of the uttermost importance to explore the yet almost unknown issue of the toxicity of this new material. We begin with illustrating the potential use of Carbon nanotubes-Silica Nanoparticles Composites in Biomedicine. Silica nanoparticles have been widely used for biosensing and catalytic applications due to their large surface area-to-volume ratio, straightforward manufacture, and the compatibility of silica chemistry with covalent coupling of biomolecules. Carbon nanotubes–composite materials, such as those based on Carbon nanotubes bound to nanoparticles, are suitable, in order to tailor Carbon nanotubes properties for specific applications. Here, we present a tunable synthesis of Multi Walled Carbon nanotubes–Silica nanoparticles. The control of the nanotube morphology and the bead size, coupled with the versatility of silica chemistry, makes these structures an excellent platform for the development of biosensors (optical, magnetic and catalytic applications). Then, we compare the toxicity of pristine and oxidized Multi Walled Carbon nanotubes on human T cells - which would be among the first exposed cell types upon intravenous administration of Carbon nanotubes in therapeutic and diagnostic nanodevices. Our results suggest that carbon nanotubes indeed can be very toxic and induce massive loss of cell viability through programmed cell death at sufficiently high concentrations (>1ng/cell). The cytotoxicity of Carbon nanotubes does depend on many other factors than concentration, including their physical form, diameter, length, and the nature of attached molecules or nanomaterials: carbon black, for instance, is less toxic than pristine CNTs (which shows the relevance of structure and topology); oxidized CNTs are more toxic than pristine CNTs. We conclude that careful toxicity studies need to be undertaken particularly in conjunction with nanomedical applications of Carbon nanotubes.