Peptide secondary structure modulates single-walled carbon nanotube fluorescence as a chaperone sensor for nitroaromatics

Proc Natl Acad Sci U S A. 2011 May 24;108(21):8544-9. doi: 10.1073/pnas.1005512108. Epub 2011 May 9.

Abstract

A class of peptides from the bombolitin family, not previously identified for nitroaromatic recognition, allows near-infrared fluorescent single-walled carbon nanotubes to transduce specific changes in their conformation. In response to the binding of specific nitroaromatic species, such peptide-nanotube complexes form a virtual "chaperone sensor," which reports modulation of the peptide secondary structure via changes in single-walled carbon nanotubes, near-infrared photoluminescence. A split-channel microscope constructed to image quantized spectral wavelength shifts in real time, in response to nitroaromatic adsorption, results in the first single-nanotube imaging of solvatochromic events. The described indirect detection mechanism, as well as an additional exciton quenching-based optical nitroaromatic detection method, illustrate that functionalization of the carbon nanotube surface can result in completely unique sites for recognition, resolvable at the single-molecule level.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adsorption
  • Fluorescence
  • Hydrocarbons, Aromatic / analysis*
  • Microscopy / instrumentation
  • Molecular Chaperones / analysis*
  • Nanotubes, Carbon / chemistry*
  • Nitro Compounds / analysis*
  • Peptides / chemistry*
  • Protein Structure, Secondary

Substances

  • Hydrocarbons, Aromatic
  • Molecular Chaperones
  • Nanotubes, Carbon
  • Nitro Compounds
  • Peptides
  • bombolitins