title: Stable gold nanoparticle conjugation to internal DNA positions: facile generation of discrete gold nanoparticle-DNA assemblies.
abstract: A straightforward strategy to stably anchor one or more gold nanoparticles (AuNPs) at both the internal and terminal positions of single-stranded DNA is presented. Discrete DNA-AuNP conjugates are isolated using a noncovalent extension strand strategy, that helps to resolve prepared species by agarose gel electrophoresis (AGE). These are used to assemble well-defined AuNP squares and rectangles. Two complementary bis-AuNP-labeled DNA conjugates are then prepared. One of these places two smaller (5 nm) AuNPs at defined internal positions within a DNA strand, and the other places two larger (13 nm) AuNPs at each of its terminal positions. We show the self-assembly of these bis-AuNP conjugates into a tapered tetrameric gold nanoparticle "antenna" structures of direct relevance to engineered "hot spots" and surface enhanced Raman scattering (SERS) substrates.
authors.affiliation: Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, Quebec, Canada.
authors.forename: Yongqiang
authors.initials: Y
authors.lastname: Wen
authors.forename: Christopher K
authors.initials: CK
authors.lastname: McLaughlin
authors.forename: Pik Kwan
authors.initials: PK
authors.lastname: Lo
authors.forename: Hua
authors.initials: H
authors.lastname: Yang
authors.forename: Hanadi F
authors.initials: HF
authors.lastname: Sleiman
mesh_terms: D001665:Binding Sites; D004247:DNA / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D013059:Spectrum Analysis, Raman; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013499:Surface Properties
chemical_list: D013438:Sulfhydryl Compounds; D006046:Gold; D004247:DNA