TY - CONF A1 - Heck, Christian T1 - Gold nanolenses on DNA origami substrates for surface-enhanced Raman scattering N2 - Surface-enhanced Raman scattering (SERS) exploits the enhancement of electromagnetic fields in close vicinity of plasmonic nanostructures, enabling characterization of analytes at the single-molecule level. The nanometer-scale spatial arrangement of plasmonic metal nanoparticles and analyte molecules has a significant effect on the observed signal enhancements and represents a great challenge in this technique. In our work, DNA origami is used as platform for precise positioning of gold nanoparticles (AuNPs). Especially high sensitivities are expected for gold nanolenses (AuNLs), consisting of rows of three or more differently-sized AuNPs. We assembled different AuNL designs and determined respective SERS enhancement factors by collecting Raman spectra from single AuNLs. Finite difference time domain calculations estimate attainable electromagnetic field enhancements. Ultimately, we aim to develop a versatile platform for various SERS applications. T2 - DNA meets Plasmonics Konferenz CY - Bad Honnef, Germany DA - 07.12.2015 KW - DNA origami KW - SERS KW - Plasmonics PY - 2015 AN - OPUS4-35906 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heck, Christian A1 - Prinz, Julia A1 - Dathe, A. A1 - Merck, V. A1 - Stranik, O. A1 - Fritzsche, W. A1 - Kneipp, Janina A1 - Bald, Ilko T1 - Gold nanolenses self-assembled by DNA origami N2 - Nanolenses are self-similar chains of metal nanoparticles, which can theoretically provide extremely high field enhancements. Yet, the complex structure renders their synthesis challenging and has hampered closer analyses so far. Here, DNA origami is used to self-assemble 10, 20, and 60 nm gold nanoparticles as plasmonic gold nanolenses (AuNLs) in solution and in billions of copies. Three different geometrical arrangements are assembled, and for each of the three designs, surface-enhanced Raman scattering (SERS) capabilities of single AuNLs are assessed. For the design which shows the best properties, SERS signals from the two different internal gaps are compared by selectively placing probe dyes. The highest Raman enhancement is found for the gap between the small and medium nanoparticle, which is indicative of a cascaded field enhancement. KW - DNA origami KW - SERS KW - Gold nanoparticles KW - Plasmonics PY - 2017 UR - http://pubs.acs.org/doi/pdf/10.1021/acsphotonics.6b00946 DO - https://doi.org/10.1021/acsphotonics.6b00946 SN - 2330-4022 VL - 4 IS - 5 SP - 1123 EP - 1130 AN - OPUS4-40587 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -