<u>The SWCNT-DNA hybrid for imaging and vector delivery applications </u> A. Adesina, S. Pourianejad, T. Ignatova <i>Nanoscience Department, University of North Carolina at Greensboro, Greensboro, NC, USA</i>

Single Wall Carbon Nanotubes (SWCNTs), being quasi-one-dimensional materials, are extensively investigated for intracellular imaging and bio-sensing applications since discovery of the hybridization of ssDNA molecules to SWCNTs.When functionalized, SWCNT can be introduced within the cell and co-localized with the sub-cellular organelles. SWCNTs exhibit resonance Raman scattering, with sharp, high intensity Raman peaks quite different from that of the hybrid or the cell itself.Raman signal of SWCNTs is chirality specific hence it can be used for nanotube identification and to assess their aggregation in cell environment. The long-term intracellular studies of SWCNTs within neural stem cells have been conducted using micro-Raman spectroscopy indicating the viability of SWCNTs as an efficient tracking agent.Additionally, we investigated the affinity of the ssDNA for SWCNT in presence of complementary strand. Here, the results on the equilibrium and dynamic study of DNA displacement from the nanotube surface, temperature dependence, Manning-Oosawa counterion condensation, and pH variation will be presented.