title: Tailor-made conjugated polymer nanoparticles for multicolor and multiphoton cell imaging.
abstract: Sonogashira coupling of dibromo- and diethynyl-substituted benzenes and fluorenes in aqueous mini-emulsion afforded colloidally stable dispersions of highly fluorescent 60-120 nm particles of poly(arylene ethynylene)s of molecular weights M(n) 4 × 10(4)-2 × 10(5) g mol(-1) with solids contents up to 15 wt %. By covalent incorporation of diethynyl pyrrolo-pyrrole or diethynyl fluorenone in the mini-emulsion polymerization the emission color of these photostable nanoparticles can be tuned from blue (λ(em max) 470) to orange at a given excitation wavelength due to an efficient energy transfer to these acceptors. Two-photon action cross sections of the particles amount to 10(6) to 10(7) GM. The particles from emulsion polymerization are taken up by HeLa cells without an adverse effect on the cells. Differentiation of the location in cells of particle species varying in emission color was demonstrated for both linear and two-photon excitation microscopy in the NIR regime.
authors.affiliation: University of Konstanz, Department of Chemistry, Universitätsstrasse 10, Konstanz, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Pecher
authors.forename: Johannes
authors.initials: J
authors.lastname: Huber
authors.forename: Martin
authors.initials: M
authors.lastname: Winterhalder
authors.forename: Andreas
authors.initials: A
authors.lastname: Zumbusch
authors.forename: Stefan
authors.initials: S
authors.lastname: Mecking
mesh_terms: D001555:Benzene Derivatives / Q000737:chemistry*; D005449:Fluorenes / Q000737:chemistry*; D005453:Fluorescence; D006367:HeLa Cells; D006801:Humans; D036641:Microscopy, Fluorescence, Multiphoton; D057054:Molecular Imaging; D015394:Molecular Structure; D008970:Molecular Weight; D053758:Nanoparticles / Q000737:chemistry*; D038761:Photobleaching; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry; D013050:Spectrometry, Fluorescence
chemical_list: D001555:Benzene Derivatives; D005449:Fluorenes; D011108:Polymers