title: Helical polycarbodiimide cloaking of carbon nanotubes enables inter-nanotube exciton energy transfer modulation.
abstract: The use of single-walled carbon nanotubes (SWCNTs) as near-infrared optical probes and sensors require the ability to simultaneously modulate nanotube fluorescence and functionally derivatize the nanotube surface using noncovalent methods. We synthesized a small library of polycarbodiimides to noncovalently encapsulate SWCNTs with a diverse set of functional coatings, enabling their suspension in aqueous solution. These polymers, known to adopt helical conformations, exhibited ordered surface coverage on the nanotubes and allowed systematic modulation of nanotube optical properties, producing up to 12-fold differences in photoluminescence efficiency. Polymer cloaking of the fluorescent nanotubes facilitated the first instance of controllable and reversible internanotube exciton energy transfer, allowing kinetic measurements of dynamic self-assembly and disassembly.
authors.affiliation: Memorial Sloan Kettering Cancer Center , New York, New York 10065, United States.
authors.forename: Januka
authors.initials: J
authors.lastname: Budhathoki-Uprety
authors.forename: Prakrit V
authors.initials: PV
authors.lastname: Jena
authors.forename: Daniel
authors.initials: D
authors.lastname: Roxbury
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Heller
mesh_terms: D002234:Carbodiimides / Q000737:chemistry*; D004735:Energy Transfer; D037742:Nanotubes, Carbon
chemical_list: D002234:Carbodiimides; D037742:Nanotubes, Carbon