title: Stable luminescence from individual carbon nanotubes in acidic, basic, and biological environments.
abstract: Aqueous surfactant suspensions of single walled carbon nanotubes (SWNTs) are very sensitive to environmental conditions. For example, the photoluminescence of semiconducting SWNTs varies significantly with concentration, pH, or salinity. In most cases, these factors restrict the range of applicability of SWNT suspensions. Here, we report a simple strategy to obtain stable and highly luminescent individualized SWNTs at pH values ranging from 1 to 11, as well as in highly saline buffers. This strategy relies on combining SWNTs previously suspended in sodium dodecylbenzene sulfonate (SDBS) with biocompatible poly(vinyl pyrrolidone) (PVP), which can be polymerized in situ to entrap the SWNT-SDBS micelles. We present a model that accounts for the photoluminescence stability of these suspensions based on PVP morphological changes at different pH values. Moreover, we demonstrate the effectiveness of these highly stable suspensions by imaging individual luminescent SWNTs on the surface of live human embryonic kidney cells (HEK cells).
authors.affiliation: Department of Chemical and Biomolecular Engineering, Carbon Nanotechnology Laboratory, Rice University, 6100 Main Street, Houston, Texas 77005, USA.
authors.forename: Juan G
authors.initials: JG
authors.lastname: Duque
authors.forename: Laurent
authors.initials: L
authors.lastname: Cognet
authors.forename: A Nicholas G
authors.initials: AN
authors.lastname: Parra-Vasquez
authors.forename: Nolan
authors.initials: N
authors.lastname: Nicholas
authors.forename: Howard K
authors.initials: HK
authors.lastname: Schmidt
authors.forename: Matteo
authors.initials: M
authors.lastname: Pasquali
mesh_terms: D001557:Benzenesulfonates / Q000737:chemistry*; D002021:Buffers; D002460:Cell Line; D006801:Humans; D006863:Hydrogen-Ion Concentration; D049449:Luminescence; D008823:Micelles; D015394:Molecular Structure; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011145:Polyvinyls / Q000737:chemistry*; D011759:Pyrrolidines / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013501:Surface-Active Agents / Q000737:chemistry*; D013535:Suspensions / Q000737:chemistry; D013997:Time Factors
chemical_list: D001557:Benzenesulfonates; D002021:Buffers; D008823:Micelles; D037742:Nanotubes, Carbon; D011145:Polyvinyls; D011759:Pyrrolidines; D013501:Surface-Active Agents; D013535:Suspensions; C505150:poly(N-vinylpyrrolidine); C001114:dodecylbenzenesulfonic acid