title: Quantitative Single-Molecule Surface-Enhanced Raman Scattering by Optothermal Tuning of DNA Origami-Assembled Plasmonic Nanoantennas.
abstract: DNA origami is a powerful approach for assembling plasmonic nanoparticle dimers and Raman dyes with high yields and excellent positioning control. Here we show how optothermal-induced shrinking of a DNA origami template can be employed to control the gap sizes between two 40 nm gold nanoparticles in a range from 1 to 2 nm. The high field confinement achieved with this optothermal approach was demonstrated by detection of surface-enhanced Raman spectroscopy (SERS) signals from single molecules that are precisely placed within the DNA origami template that spans the nanoparticle gap. By comparing the SERS intensity with respect to the field enhancement in the plasmonic hot-spot region, we found good agreement between measurement and theory. Our straightforward approach for the fabrication of addressable plasmonic nanosensors by DNA origami demonstrates a path toward future sensing applications with single-molecule resolution.
authors.affiliation: Photonics and Optoelectronics Group, Department of Physics and Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität München , Amalienstraße 54, Munich 80799, Germany.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Simoncelli
authors.affiliation: Department of Physics and Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität München , Geschwister-Scholl-Platz 1, Munich 80539, Germany.
authors.forename: Eva-Maria
authors.initials: EM
authors.lastname: Roller
authors.affiliation: Photonics and Optoelectronics Group, Department of Physics and Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität München , Amalienstraße 54, Munich 80799, Germany.
authors.forename: Patrick
authors.initials: P
authors.lastname: Urban
authors.affiliation: Clarendon Laboratory, Department of Physics, University of Oxford , Parks Road, Oxford OX1 3PU, United Kingdom.
authors.forename: Robert
authors.initials: R
authors.lastname: Schreiber
authors.affiliation: Clarendon Laboratory, Department of Physics, University of Oxford , Parks Road, Oxford OX1 3PU, United Kingdom.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Turberfield
authors.affiliation: Department of Physics and Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität München , Geschwister-Scholl-Platz 1, Munich 80539, Germany.|Nanosystems Initiative Munich (NIM) , Schellingstraße 4, Munich 80539, Germany.
authors.forename: Tim
authors.initials: T
authors.lastname: Liedl
authors.affiliation: Photonics and Optoelectronics Group, Department of Physics and Center for Nanoscience (CeNS), Ludwig-Maximilians-Universität München , Amalienstraße 54, Munich 80799, Germany.|Nanosystems Initiative Munich (NIM) , Schellingstraße 4, Munich 80539, Germany.
authors.forename: Theobald
authors.initials: T
authors.lastname: Lohmüller
mesh_terms: D004247:DNA / Q000737:chemistry*; D006046:Gold; D053768:Metal Nanoparticles; D036103:Nanotechnology; D013059:Spectrum Analysis, Raman
chemical_list: D006046:Gold; D004247:DNA
keywords: DNA Origami; SERS; plasmonic heating; single molecule