title: Formation of bimetallic Ag-Au nanowires by metallization of artificial DNA duplexes.
abstract: Uniform bimetallic nanowires, tunable in size, have been grown on artificial DNA templates via a two-step metallization process. Alkyne-modified cytosines were incorporated into 900-base-pair polymerase-chain-reaction fragments. The alkyne modifications serve as addressable metal-binding sites after conversion to a sugar triazole derivative via click chemistry. Reaction of the Tollens reagent with these sugar-coated DNA duplexes generates Ag0 metallization centers around the sugar modification sites of the DNA. After a subsequent enhancement step using gold, nanowires < or = 10 nm in diameter with a homogeneous surface profile were obtained. Furthermore, the advantage of this two-step procedure lies in the high selectivity of the process, due to the exact spatial control of modified DNA base incorporation and hence the confinement of metallization centers at addressable sites. Besides experiments on a membrane as a proof for the selectivity of the method, atomic force microscopy (AFM) studies of the wires produced on Si-SiO2 surfaces are discussed. Furthermore, we demonstrate time-dependent metallization experiments, monitored by AFM.
authors.affiliation: Institut für Anorganische Chemie, RWTH Aachen, Landoltweg 1, 52074 Aachen, Germany.
authors.forename: Monika
authors.initials: M
authors.lastname: Fischler
authors.forename: Ulrich
authors.initials: U
authors.lastname: Simon
authors.forename: Hadar
authors.initials: H
authors.lastname: Nir
authors.forename: Yoav
authors.initials: Y
authors.lastname: Eichen
authors.forename: Glenn A
authors.initials: GA
authors.lastname: Burley
authors.forename: Johannes
authors.initials: J
authors.lastname: Gierlich
authors.forename: Philipp M E
authors.initials: PM
authors.lastname: Gramlich
authors.forename: Thomas
authors.initials: T
authors.lastname: Carell
mesh_terms: D020029:Base Pairing; D040761:Biomimetic Materials / Q000737:chemistry*; D002241:Carbohydrates / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D053770:Nanowires / Q000737:chemistry*; D009692:Nucleic Acid Heteroduplexes / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification / Q000648:ultrastructure; D012441:Saccharomyces cerevisiae; D012834:Silver / Q000737:chemistry*; D013997:Time Factors
chemical_list: D002241:Carbohydrates; D009692:Nucleic Acid Heteroduplexes; D012834:Silver; D006046:Gold; D004247:DNA