title: Bright quantum-dot-sized single-chain conjugated polyelectrolyte nanoparticles: synthesis, characterization and application for specific extracellular labeling and imaging.
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.
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, 117576.
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.forename: Guangxue
authors.initials: G
authors.lastname: Feng
authors.forename: Rongrong
authors.initials: R
authors.lastname: Liu
authors.forename: Nikodem
authors.initials: N
authors.lastname: Tomczak
authors.forename: Lin
authors.initials: L
authors.lastname: Ma
authors.forename: Gagik G
authors.initials: GG
authors.lastname: Gurzadyan
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
mesh_terms: D058948:Cell Tracking / Q000379:methods*; D004573:Electrolytes; D005456:Fluorescent Dyes / Q000138:chemical synthesis*; D008422:Materials Testing; D008856:Microscopy, Fluorescence / Q000379:methods*; D057054:Molecular Imaging / Q000379:methods*; D058726:Nanoconjugates / Q000737:chemistry / Q000648:ultrastructure; D045663:Quantum Dots; D013194:Staining and Labeling / Q000379:methods
chemical_list: D004573:Electrolytes; D005456:Fluorescent Dyes; D058726:Nanoconjugates
keywords: benzoxadiazole; conjugated polyelectrolyte; extracellular labeling; fluorene; single-chain nanoparticles; ultrasonication