Oxidatively Induced Damage to DNA: Potential Roles of Single- and Multi-Wall Carbon Nanotubes at the Molecular Level

B.C. Nelson
National Institute of Standards and Technology, US

Keywords: carbon nanotubes, DNA damage, molecular level investigation, free radicals


Carbon nanotubes (CNTs) are remarkable materials in terms of their enhanced thermal and electrical conductivities, tensile strengths and mechanical properties. Because of these unique properties, the commercial development and application of CNTs in electronics, advanced materials, sporting equipment and targeted drug delivery, for example, is expanding at a phenomenal pace. However, our understanding and characterization of the potential environmental, health and safety risks of these novel nanomaterials is incomplete and is, in fact, lagging behind the commercial development of CNTs. Our group develops and applies hyphenated tandem mass spectrometry techniques (LC/MS/MS & GC/MS/MS) to understand the fundamental interaction mechanisms of engineered nanomaterials with nucleic acids. We demonstrate and propose a mechanistic basis for how single wall carbon nanotubes (SWCNTs) in close contact with oligomeric DNA can act as effective scavengers of free radicals, and thus inhibit the formation and accumulation of DNA lesions. In a second study, we demonstrate and propose a mechanistic basis for how MWCNTs are able to enter cells, enter the nucleus of the cells and generate free radicals and yet fail to produce significant levels of oxidative damage to genomic DNA.