Plasmons as sensors [Elektronische Ressource] / vorgelegt von Jan Becker

Informations

• Publié par: johannes_gutenberg-universitat_mainz
• Publié le: 01 janvier 2010
• Nombre de lectures: 52
• Langue: Deutsch
• Poids de l'ouvrage: 17 Mo

Extrait

Plasmons as Sensors
Dissertation zur Erlangung des Grades
“Doktor der Naturwissenschaften”
am Fachbereich
Chemie, Pharmazie und Geowissenschaften
der Johannes-Gutenberg Universität Mainz
vorgelegt von
Jan Becker
aus Heidelberg
März 2010Dekan:
Erster Gutachter:
Zweiter Gutachter:
Tag der mündlichen Prüfung: 20.05.2010
iIwouldliketoacknowledgetheCarl-ZeissFoundationforprovidingmeaPhDscholarship.
iiScientific Publications
Parts of this thesis have been published in scientific journals:
“Gold Nanoparticle Growth Monitored in situ Using a Novel Fast Optical Single-Particle
Spectroscopy Method”
J. Becker, O. Schubert, and C. Sönnichsen
Nano Letters, Year: 2007, Vol. 7, Pages: 1664 - 1669
“Plasmonic Focusing Reduces Ensemble Linewidth of Silver-Coated Gold Nanorods”

J. Becker , I. Zins , A. Jakab, Y. Khalavka, O. Schubert, and C. Sönnichsen
Nano Letters, Year: 2008, Vol. 8, Pages: 1719 - 1723
“Protein-Membrane Interaction Probed by Single Plasmonic Nanoparticles”

C. Baciu , J. Becker , A. Janshoff, and C. Sönnichsen
Nano Letters, Year: 2008, Vol. 8, Pages: 1724 - 1728
“Mapping the Polarization Pattern of Plasmon Modes Reveals Nanoparticle Symmetry”
O. Schubert, J. Becker, L. Carbone, Y. Khalavka, T. Provalska, I. Zins, and C. Sönnichsen
Nano Letters, Year: 2008, Vol. 8, Pages: 2345 - 2350
“Synthesis of Rod-Shaped Gold Nanorattles with Improved Plasmon Sensitivity and Cat-
alytic Activity”
Y. Khalavka, J. Becker, and C. Sönnichsen
Journal of the American Chemical Society, Year: 2009, Vol. 131, Pages: 1871 - 1875
“The Optimal Aspect Ratio of Gold Nanorods for Plasmonic Bio-Sensing”
J. Becker, A. Trügler, A. Jakab, U. Hohenester, and C. Sönnichsen
Plasmonics, Year: 2010, Vol. 5, Pages: 161 - 167
Parts of this thesis are in preparation for scientific publication:
“Parallel Investigation of Local Refractive Index and Interparticle Distance of Dimers”
J. Becker, I. Zins, A. Henkel, O. Schubert, and C. Sönnichsen
Authors contributed equally, in alphabetic order
iiiAdditional scientific publications during PhD (not presented in
this thesis):
“A Nanoassembled Plasmonic-Photonic Hybrid Cavity for Tailored Light-Matter Coupling”
M. Barth, S. Schietinger, S. Fischer, J. Becker, N. Nüsse, T. Eichele, B. Löchel, C. Sön-
nichsen, and O. Benson
Nano Letters, Year: 2010, Vol. 10, Pages: 891 - 895
“Au@MnONanoflowers: Hybrid Nanocomposites for Selective Dual Functionalization and
Imaging”
T. D. Schladt, M. I. Shukoor, K. Schneider, M. N. Tahir, F. Natalio, I. Ament, J. Becker,
F. D. Jochum, S. Weber, O. Köhler, P. Theato, L. M. Schreiber, C. Sönnichsen, H. C.
Schröder, W. E. G. Müller, and W. Tremel
Angewandte Chemie International Edition, Year: 2010, Vol. 49, Pages: 3976 - 3980
“Nanoscale pH-Sensing with Polymer-Coated Gold Nanorods”
I. Ament, J. Becker, and C. Sönnichsen
In preparation
ivConference Contributions
Talks:
“Gold Nanorods as Novel Nonbleaching Plasmon-Based Sensors for Molecular Orienta-
tions and Local Refractive Index Changes”
Spring Meeting of the German Physical Society, Dresden (Germany), March 2006
“Protein-Membrane Interaction Probed by Single Plasmonic Nanoparticles”
Heraeus-Seminar “Ultrafast Nanooptics”, Bad Honnef (Germany), Juni 2008
“Single Plasmonic Nanoparticles as Biosensors” (Invited Talk)
Fall meeting of the European Materials Research Society (E-MRS), Warsaw (Poland),
September 2008
“Protein-Membrane Interaction Probed by Single Plasmonic Nanoparticles”
Annual Meeting of the Optical Society of America (OSA), Rochester, NY (USA), Novem-
ber 2008
Posters:
“Fast Optical Single-Particle Spectroscopy of Metal Particles ”
Annual Meeting of the Material Reserach Center (MFWZ), Mainz (Germany), June 2006
“Nanoparticle Growth Investigated Optically on Single Particles With a Novel Fast Spec-
troscopy Method”
Trends in Nanoscience, Kloster Irsee (Germany), February 2007
“Fast, Continuous and Parallel Spectroscopy of Single Nanoparticles ”
Meeting of the Collaborative Research Centre 625, Mainz (Germany), September 2007
“FastSPS shows: Silver Coating Improves the Optical Properties of Gold Nanorods” Inter-
nationalSummerSchoolNicolasCabrera: NanophotonicsandOptics,Madrid(Spain),September
2007
“Nanoparticle Growth Investigated Optically on Single Particles With a Novel Fast Spec-
troscopy Method”
rd43 Meeting of the German Colloid Society, Mainz (Germany), October 2007
v“Plasmonic Focusing Reduces Ensemble Linewidth of Silver-Coated Gold Nanorods”
Annual Meeting of the Material Reserach Center (MWFZ), Mainz (Germany), June 2008
“Protein-Membrane Interaction Probed by Single Plasmonic Nanoparticles”
Annual Meeting of the Material Reserach Center (MWFZ), Mainz (Germany), June 2008
“Nanorattles Improve Plasmonic Sensitivity”
Annual Meeting of the Material Reserach Center (MWFZ), Mainz (Germany), June 2008
“Protein-Membrane Interaction Probed by Single Plasmonic Nanoparticles”
International Workshop on Optical Properties of Coupled Semiconductors and Metallic
Nanoparticles, Dresden (Germany), July 2008
Seminar Talks:
Biophysical Chemistry Group (Prof. Dr. Andreas Janshoff)
University of Mainz (Germany), Februar 2007
Colloid Chemistry Group (Prof. Dr. Luis Liz-Marzan)
University of Vigo (Spain), July 2008
Nanooptics Group (Prof. Dr. Oliver Benson)
Humboldt University of Berlin (Germany), January 2009
viAbstract
“Plasmon” is a synonym for collective oscillations of the conduction electrons in a metal
nanoparticle (excited by an incoming light wave), which cause strong optical responses
like efficient light scattering. The scattering cross-section with respect to the light wave-
length depends not only on material, size and shape of the nanoparticle, but also on the
refractive index of the embedding medium. For this reason, plasmonic nanoparticles are
interesting candidates for sensing applications. Here, two novel setups for rapid spectral
investigations of single nanoparticles and different sensing experiments are presented.
Precisely, thenovelsetupsarebasedonanopticalmicroscopeoperatedindarkfieldmodus.
For the fast single particle spectroscopy (fastSPS) setup, the entrance pinhole of a coupled
spectrometer is replaced by a liquid crystal device (LCD) acting as spatially addressable
electronic shutter. This improvement allows the automatic and continuous investigation
of several particles in parallel for the first time. The second novel setup (RotPOL) uses
a rotating wedge-shaped polarizer and encodes the full polarization information of each
particle within one image, which reveals the symmetry of the particles and their plasmon
modes. Both setups are used to observe nanoparticle growth in situ on a single-particle
level to extract quantitative data on growth.
Using the fastSPS setup, I investigate the membrane coating of gold nanorods in aque-
ous solution and show unequivocally the subsequent detection of protein binding to the
membrane. This binding process leads to a spectral shift of the particles resonance due
to the higher refractive index of the protein compared to water. Hence, the nanosized
addressable sensor platform allows for local analysis of protein interactions with biological
membranes as a function of the lateral composition of phase separated membranes.
The sensitivity on changes in the environmental refractive index depends on the particles’
aspect ratio. On the basis of simulations and experiments, I could present the existence of
an optimal aspect ratio range between 3 and 4 for gold nanorods for sensing applications.
A further sensitivity increase can only be reached by chemical modifications of the gold
nanorods. This can be achieved by synthesizing an additional porous gold cage around
the nanorods, resulting in a plasmon sensitivity raise of up to 50 % for those “nanorattles”
compared to gold nanorods with the same resonance wavelength. Another possibility is
to coat the goldds with a thin silver shell. This reduces the single particle’s reso-
nance spectral linewidth about 30 %, which enlarges the resolution of the observable shift.
Thissilvercoatingevokestheinterestingeffectofreducingtheensembleplasmonlinewidth
by changing the relation connecting particle shape and plasmon resonance wavelength.
This change, I term plasmonic focusing, leads to less variation of wavelengths
for the same particle size distribution, which I show experimentally and theoretically.
In a system of two coupled nanoparticles, the plasmon modes of the transversal and
longitudinalaxisdependontherefractiveindexoftheenvironmentalsolution,butonlythe
latter one is influenced by the interparticle distance. I show that monitoring both modes
provides a self-calibrating system, where interparticle distance variations and changes of
the environmental refractive index can be determined with high precision.
vii