title: Gel electrophoresis using a selective radical for the separation of single-walled carbon nanotubes.
abstract: We have applied agarose gel electrophoresis (AGE) to single-walled carbon nanotubes (SWNTs) that have been pre-reacted with metallic-selective ionic radicals and then re-suspended with sodium cholate (SC) surfactant to obtain highly purified (up to 98%) semiconducting single-walled carbon nanotubes (s-SWNTs). The proposed combination method exploits the preferential reactivity with the metallic nanotube of the radicals generated from an azo naphthalene compound (Direct Blue 71(I)) to preferentially increase the surface charge, and therefore the electrophoretic mobilities, of the metallic nanotube population under the influence of the electric field in AGE. The excellent separation achieved was verified by UV-vis-NIR and Raman spectroscopy as well as by the performance of field effect transistors fabricated with semiconducting-enriched SWNTs. FETs fabricated with -assisted AGE-separated semiconducting nanotubes exhibited mobilities of ∼3.6 to 11.7 cm(2) V(-1) s(-1) and on/off ratios from 10(2) to 10(6).
authors.affiliation: School of Chemical & Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore. mbechan@ntu.edu.sg.
authors.forename: Sara
authors.initials: S
authors.lastname: Mesgari
authors.forename: Ashok Kumar
authors.initials: AK
authors.lastname: Sundramoorthy
authors.forename: Leslie S
authors.initials: LS
authors.lastname: Loo
authors.forename: Mary B
authors.initials: MB
authors.lastname: Chan-Park
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D004587:Electrophoresis, Agar Gel; D005609:Free Radicals / Q000138:chemical synthesis*; D037742:Nanotubes, Carbon / Q000032:analysis / Q000737:chemistry*; D012666:Semiconductors; D020358:Sodium Cholate / Q000737:chemistry; D055672:Static Electricity; D013499:Surface Properties; D014173:Transistors, Electronic
chemical_list: D001391:Azo Compounds; D005609:Free Radicals; D037742:Nanotubes, Carbon; C408744:Direct Blue 71; D020358:Sodium Cholate