1. Results
600 700 800
0
0.5
1
Wavelength (nm)
Norm.Intensity
Scattering
Photoluminescence
Control
600 650 700 750 800 850
0
0.5
1
Wavelength (nm)
Norm.Intensity
5 mM MV
550 600 650 700 750 800 850
0
0.5
1
Wavelength (nm)
NormalizedIntensity
1 M MV
Photoluminescence and scattering of gold
nanorods.
Acknowledgements
I would like to thank my mentor, Anneli Hoggard, for
guiding me through this experiment and to Joey Tauzin for
assisting me with my poster. I would also like to thank Rice
University chemistry department and Dr. Stephan Link for
allowing me to work in his lab.
500 600 700 800 900
0
0.5
1
Wavelength (nm)
NormalizedIntensity
Before MV
After MV
1 M MV solution
600 700 800
0
0.005
0.01
0.015
0.02
0.025
0.03
Wavelength (nm)
Intensity
Before MV
After MV
5 mM MV solution
Conclusion
The addition of methyl viologen to the gold
nanoparticles had a significant change on its
scattering spectra, but not its luminescence. The
changes that were observed in both
concentrations, more notably in 1 M MV, were: a
red shift, a widening of the spectra, and a slight
decrease in intensity. This proves that
photoluminescence is more stable in electron
withdrawing environments.
Biological Applications
Nanoparticles have a huge potential in the
biological field. They can be great imaging probes
in cells because they are background free, bright
and stable. They can also be used in the delivery
of drugs to specific parts of the body. However,
before they can be used commercially, they need
to be understood fully and be measured
predictably and accurately.
Dark-field image of red nanoparticles
inside live pancreatic cancer cells1.
1Hu, R.; Yong, K.T.; Roy, I.; Ding, H.; He, S.;
Prasad, P.N. J. Phys. Chem. C. 2009, 113(7), 2676-
2684.
Microscope Setup
CCD
Spectrometer White light
APD
or
Dark-field
scattering
Luminescence
CCD = Charge Coupled device APD = Avalanche Photo Diode
Experimental Procedures
Camera Image 061213a_059.dat
15
20
25
30
35
40
45
50
55
60
10 µm
10µm
Scattering 061413a_100.dat
15
20
25
30
35
40
45
20 µm
20µm
Luminescence
1. Microscope calibrated to
receive maximum counts.
2. Camera image
3. APD image
4. Single Particle Spectra
5. Data analysis (Matlab, background correction,
white light standard correction)
Structure of Methyl
Viologen (MV)
Plasmon Resonance in Noble Metal Nanostructures
Guillermo Lash1, Anneli Hoggard2, Dr. Stephan Link2
1 Science Academy of South Texas 2 Dept. of Chemistry, Rice University
Charge
Cloud of Conduction Electrons
Nuclear Framework
of Nanoparticle
E-Field
e- Cloud
Plasmon Resonance is the collective
oscillation of electrons in a solid or liquid
stimulated by incident light and is the basis of
many biomedical and materials applications.
Before metal nanoparticles can be used in these
applications, we must understand their
fundamental properties.
Introduction
To determine how gold nanorods change
their light scattering through their interactions with
other molecules such as methyl viologen.
Bottle
containing a
solution of gold
nanorods
The sonicator
was used to
break up
aggregates in
solution
Special
quartz
slides with
nanogrid
Spin coater
evenly spreads
gold nanorods
and methyl
viologen
Sample Preparation
1. Gold nanorod solution was stirred using
sonicator
2. Quartz slides were peeled and placed on spin
coater
3. Solution was pipetted onto the slides
4. Spin coater was activated and solution spread
out evenly on the surface of the slides.
Objective