TY  - JOUR
A1  - Eerqing, Narima
A1  - Subramanian, Sivaraman
A1  - Rubio Jimenez, Jesus
A1  - Lutz, Tobias
A1  - Wu, Hsin-Yu
A1  - Anders, Janet
A1  - Soeller, Christian
A1  - Vollmer, Frank
T1  - Comparing transient oligonucleotide hybridization kinetics using DNA-PAINT and optoplasmonic single-molecule sensing on gold nanorods
JF  - ACS photonics / American Chemical Society
N2  - We report a comparison of two photonic techniques for single-molecule sensing: fluorescence nanoscopy and optoplasmonic sensing. As the test system, oligonucleotides with and without fluorescent labels are transiently hybridized to complementary "docking" strands attached to gold nanorods. Comparing the measured single-molecule kinetics helps to examine the influence of the fluorescent labels as well as factors arising from different sensing geometries. Our results demonstrate that DNA dissociation is not significantly altered by the fluorescent labels and that DNA association is affected by geometric factors in the two techniques. These findings open the door to exploiting plasmonic sensing and fluorescence nanoscopy in a complementary fashion, which will aid in building more powerful sensors and uncovering the intricate effects that influence the behavior of single molecules.
KW  - single-molecule
KW  - plasmonics
KW  - whispering gallery modes
KW  - optoplasmonic
KW  - DNA-PAINT
KW  - fluorescence
KW  - localization microscopy
Y1  - 2021
U6  - https://doi.org/10.1021/acsphotonics.1c01179
SN  - 2330-4022
VL  - 8
IS  - 10
SP  - 2882
EP  - 2888
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Kogikoski Junior, Sergio
A1  - Dutta, Anushree
A1  - Bald, Ilko
T1  - Spatial separation of plasmonic hot-electron generation and a hydrodehalogenation reaction center using a DNA wire
JF  - ACS nano
N2  - Using hot charge carriers far from a plasmonic nanoparticle surface is very attractive for many applications in catalysis and nanomedicine and will lead to a better understanding of plasmon-induced processes, such as hot-charge-carrier- or heat-driven chemical reactions. Herein we show that DNA is able to transfer hot electrons generated by a silver nanoparticle over several nanometers to drive a chemical reaction in a molecule nonadsorbed on the surface. For this we use 8-bromo-adenosine introduced in different positions within a double-stranded DNA oligonucleotide. The DNA is also used to assemble the nanoparticles into nanoparticles ensembles enabling the use of surface-enhanced Raman scattering to track the decomposition reaction. To prove the DNA-mediated transfer, the probe molecule was insulated from the source of charge carriers, which hindered the reaction. The results indicate that DNA can be used to study the transfer of hot electrons and the mechanisms of advanced plasmonic catalysts.
KW  - plasmonics
KW  - DNA nanotechnology
KW  - hot electrons
KW  - charge transfer
KW  - SERS
KW  - superlattices
Y1  - 2021
U6  - https://doi.org/10.1021/acsnano.1c09176
SN  - 1936-0851
SN  - 1936-086X
VL  - 15
IS  - 12
SP  - 20562
EP  - 20573
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Heck, Christian
A1  - Prinz, Julia
A1  - Dathe, Andre
A1  - Merk, Virginia
A1  - Stranik, Ondrej
A1  - Fritzsche, Wolfgang
A1  - Kneipp, Janina
A1  - Bald, Ilko
T1  - Gold Nanolenses Self-Assembled by DNA Origami
JF  - ACS Photonics
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  - plasmonics
KW  - DNA origami
KW  - SERS
KW  - nanolenses
KW  - gold nanoparticles
Y1  - 2017
U6  - https://doi.org/10.1021/acsphotonics.6b00946
SN  - 2330-4022
VL  - 4
SP  - 1123
EP  - 1130
PB  - American Chemical Society
CY  - Washington
ER  -