(198m) Probing the Kinetics of DNA-Surfactant Exchange Reactions for Carbon Nanotubes

Single-wall carbon nanotubes (SWCNTs) possess superior and tunable optical and electronic properties that are dependent on their helicity and handedness. Unique properties of each and every single species of SWCNTs offer possibilities in many technological applications of SWCNTs. Recent studies have shown that single-stranded DNA molecules have the ability to select structurally defined DNA-wrapped SWCNTs (DNA-SWCNTs) from their synthetic mixtures. In this work, the kinetics of DNA displacement by a surfactant for DNA-SWCNTs were measured by analyzing the spectral changes in absorption and fluorescence emission peaks of SWCNTs in the near-infrared region. The kinetics of surfactant exchange reactions were employed to characterize the binding affinity of a DNA recognition sequence for specific SWCNT species. Furthermore, the environmental impact, such as temperature, on the dispersion stability and optical properties of DNA-SWCNTs were explored. These findings will provide better understandings of sequence-dependent properties of DNA-SWCNTs and enable SWCNT applications in biosensing and imaging.