Bright quantum-dot-sized single-chain conjugated polyelectrolyte nanoparticles: synthesis, characterization and application for specific extracellular labeling and imaging

Small. 2014 Aug 13;10(15):3110-8. doi: 10.1002/smll.201303505. Epub 2014 Apr 14.

Abstract

We report a simple method to fabricate quantum-dot-sized nanoparticles (NPs) from poly[9,9-bis((6-N,N,N-trimethylammonium)hexyl)fluorene-alt-co-2,1,3-benzo-xadiazole dibromide] (PFBD). The transmission electron microscope results reveal that the obtained NPs have a mean diameter of ≈4 nm, which is composed of a single PFBD chain. The NPs show bright fluorescence with an emission maximum at ≈636 nm and a quantum yield of ≈26% in water. The fluorescence properties of the NPs are characterized by steady fluorescence microscopy, fluorescence dynamic study and single nanoparticle microscopy, which show superior brightness over commercial quantum dots QD655. The NPs are further conjugated with streptavidin to yield PFBD-SA NPs, which serve as a specific extracellular labeling and imaging probe with high specificity and good photostability.

Keywords: benzoxadiazole; conjugated polyelectrolyte; extracellular labeling; fluorene; single-chain nanoparticles; ultrasonication.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Tracking / methods*
  • Electrolytes
  • Fluorescent Dyes / chemical synthesis*
  • Materials Testing
  • Microscopy, Fluorescence / methods*
  • Molecular Imaging / methods*
  • Nanoconjugates* / chemistry
  • Nanoconjugates* / ultrastructure
  • Quantum Dots*
  • Staining and Labeling / methods

Substances

  • Electrolytes
  • Fluorescent Dyes
  • Nanoconjugates