B.S., Biochemistry/ Medieval Studies (1996), University
of California, Davis
"Quantum Dot-Organic Oligomer
Nanostructures: Electronic Excitation Migration and Optical
Memory Design" A. Javier,
C. S. Yun, Geoffrey F. Strouse*,
Mat. Res. Soc. Symp. Proc, Vol.
776, Q2.1.1 [ view
article - PDF ]
"Energy Transport in CdSe Nanocrystals
Assembled with Molecular Wires." Javier,
A.; Yun, C.S.; Sorena, J.; Strouse, G.F.
J. Phys. Chem. B, 107, 435-442
(2003).
[ view article
- PDF ]
"Effects of
Alkylamine Chain Length on the Thermal Behavior of CdSe Quantum
Dot Glassy Films." Meulenberg, R.W.; Bryan, S.;
Yun, C.S.; Strouse, G.F. J. Phys.
Chem B, 106, 7774-7780 (2002). [ view
article - PDF ]
"Enzymatic
Modulation of DNA-Nanomaterial Constructs." Yun,
C.S.; Khitrov, G.A.; Vergona, D.E.; Reich, N.O.; Strouse,
G.F. J. Amer. Chem. Soc.,
124, 7644-7645 (2002). [ view
article - PDF ]
"Inorganic
Clusters as Single Source Precursors for Preparation of CdSe,
ZnSe, CdSe/ZnS Nanomaterials." Cumberland, S.L.;
Hanif, K.M.; Javier, A.; Khitrov, G.A.; Strouse, G.F.; Woessner,
S.M.; Yun, C.S.
Chem. Mater., 14, 1576-1584 (2002).
[ view article - PDF ]
"Assembly
of Nanomaterials Using Bio-Scaffolding." Yun,
C.S.; Major, J.L.; Strouse, G.F.
Mat. Res. Soc. Symp. Proc., 642, J2.3 (2001). [ view
article - PDF ]
"Pd(0)-mediated
couplings of aryl nonaflates and triflates with diphenylphosphine-borane.
Preparation of BH3-stabilized, unsymmetrical triarylphosphines"
Lipshutz, Bruce H.; Buzard, D. J.; Yun, Chol Steve.
Tetrahedron Letters (1999), 40(2), 201-204.
The tremendous advance in understanding, utilization and control
of biomolecules provides a dramatically enhanced set of reagents,
allowing precise control over the assembly of nano-scale components
into larger construct. Next generation materials developed at
the interface between traditional inorganic materials and biological
polymers can form the basis of novel device technologies by
utilizing the highly cooperative, self-assembling capability
of biopolymers to direct the formation of 3-dimensional constructs.
Integrating nano-scale materials into biological architectures
offers intriguing potentials for novel electronic frameworks.
Biomaterials represent a burgeoning field in which the demonstration
and control of bio-compatibility between the inorganic nanomaterials
and the biological scaffolding, as well as the maintenance of
bioactivity of the biological framework is crucial to the development
of the field. We demonstrate that bio-compatibility and bio-activity
are maintained for biomaterials composed of duplex DNA appended
with 1.4 nm Au particles. We used highly selective proteins
that induce sequence-specific structural perturbations on the
DNA. Electron microscopy imaging provides a direct assessment
of the bio-activity of the DNA-Au assemblies. (Figure 6) These
results lay a foundation for interfacing more complex and diverse
protein-DNA-nanomaterial systems, and mechanism for the analysis
of the resultant conjugate structures.
In a recent study in our lab, we have
initiated a study of organic polymers as molecular scaffolding
for CdSe nano-composites. These polymer based nanocomposites
exhibit efficient energy transfer from the organc oligomers
to the nanomaterial. Energy transfer appears to be dominated
by a dipole-dipole exchange mechanism in which the size dependent
nature of this energy transfer process is clearly evident in
the loss of quantum efficiency for transfer above 5 nm. The
quenching of the polymer by appended nanoscale CdSe via directed
energy transfer proceeds with near unit quantum efficiency in
the region where the spectral overlap <J-integral> is
favorable. At 5 nm the nature of the directed energy transfer
from the polymer to CdSe can be modulated by photolysis.
The observation of a photo-initiated switch in the efficiency
of energy transfer coupled to recent crystal structures of the
oligomers suggest that structural reorientation of the composite
may lead to the opening of transverse optical energy transfer
along a pi-pi stacking direction. We are developing a series
of oligomerically linked (n = 1, 3, 5) systems based on PAO,
phenylethynylene, appended to CdSe. The PAO is linked to the
CdSe through a benzylic thiol bond. (figure 7) The size dependent
nature of energy transfer allows fine control over energy transport
from the surface of the CdSe. (figure 8)
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