title: Few-atom fluorescent silver clusters assemble at programmed sites on DNA nanotubes.
abstract: We show that DNA hairpins template the site-specific assembly of fluorescent few-atom Ag clusters on DNA nanotubes. Fluorescent clusters form only at hairpin sites and not on the double-stranded DNA scaffold, allowing for spatially programmed self-assembly. Ag clusters synthesized on hairpins protruding from DNA nanotubes can have nearly identical fluorescence spectra to those synthesized on free hairpins of identical sequence. Analysis of the stepwise photobleaching of individual clusters suggests a chemical yield of ~45%. Given the well-established sequence-specific optical properties of DNA stabilized Ag clusters, these results point the way toward high yield assembly of metal cluster fluorophores with control over spectra as well as spatial arrangement.
authors.affiliation: Physics Department, University of California, Santa Barbara, California 93106, USA.
authors.forename: Patrick R
authors.initials: PR
authors.lastname: O'Neill
authors.forename: Kevin
authors.initials: K
authors.lastname: Young
authors.forename: Daniel
authors.initials: D
authors.lastname: Schiffels
authors.forename: Deborah K
authors.initials: DK
authors.lastname: Fygenson
mesh_terms: D001483:Base Sequence; D004247:DNA / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000494:pharmacology; D053768:Metal Nanoparticles / Q000737:chemistry; D008670:Metals / Q000737:chemistry; D008969:Molecular Sequence Data; D053761:Nanocomposites / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods*; D043942:Nanotubes / Q000737:chemistry*; D055095:Optics and Photonics; D010825:Physics / Q000379:methods; D011789:Quantum Theory; D012834:Silver / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: D005456:Fluorescent Dyes; D008670:Metals; D012834:Silver; D004247:DNA