Chip-based devices and biosensors
incorporate the attachment of biomolecules
at interfaces. The behavior of biomolecules
at the surface and interfaces differs from the
behavior of biomolecules in the bulk solution.
Surface-analysis techniques are therefore
required to characterize these interfaces.
Second harmonic generation (SHG) has been
used to characterize DNA on...
In this research project, particle sorting of
Brownian liquids was explored by sweeping
two noncoherent pairs of parallel optical
standing waves in a translating medium.
Each wave was created by interfering two
coherent beams of light, and the resulting
fringe periods were determined by the angle
of intersection. Adjusting the...
In many biological systems, ligand-receptor
pairs bind to each other via noncovalent
interactions such as hydrogen-bonding and
Van der Waals forces. This project’s method
of studying these interactions uses electron
transfer theory. When a receptor binds to a
redox-modified ligand, there is a change in
the reorganization energy of the...
Germanium (Ge) nanowires were grown via
the vapor-liquid-solid growth mechanism
and surface-doped with manganese (Mn).
The nanowires were annealed at 350˚ C for
30 min to promote the Mn diffusion.
Pulsed-laser local electrode atom probe
tomography was used to determine the
concentration and distribution of Mn in the
Ge nanowires....
Silver nanoparticles exhibit distinctive
optical properties. When exposed to
electromagnetic radiation, a noble metal
nanoparticle demonstrates the unique
optical property of localized surface
plasmon resonance (LSPR). LSPR is
measured through an extinction spectrum,
the sum of absorption and Rayleigh
scattering, which results when the
collective oscillation of electrons is
resonant...
When the Aß peptides aggregate into
soluble oligomeric clusters, they form
central nervous system neurotoxins known
as amyloid-ß-derived diffusible ligands
(ADDLs). The assembly of ADDLs is
currently thought to be a pathogenic
process in Alzheimer's disease (AD).
Understanding the molecular structure and
properties of ADDLs could prove useful in
the...
Numerous studies have been structured to
investigate magnetoelectric multiferroic
materials, which possess simultaneous
ferroelectric and (anti)ferromagnetic
ordering. Bismuth ferrite (BiFeO3), referred
to as BFO, has drawn special attention
because of its unique ability to maintain both
electric and magnetic dipole moments at
room temperature. BFO shows great
potential to revolutionize...
A self-assembled monolayer of an alkene or
alkyne can be applied to a hydrogenpassivated
silicon surface using UV hydrosilylation.
This research shows that
field-induced oxides can be used as a
negative resist to selectively prevent
bromostyrene attachment, providing a
means of nanopatterning organic molecules
on silicon. The negative resist effects...
Pressure-assisted densification was used
by way of a hot press to optimize the
conditions of heat and pressure when
applied to anatase (TiO2). This study
optimized hot-pressing conditions, which
will be helpful when doping TiO2 because it
will allow optimization of bulk anatase for
transparent conductive oxide (TCO)
applications. Lessons...
Magnetic tweezers are a simple yet
powerful tool for the micromanipulation of
single molecules. In this study, a vertical
magnetic tweezer apparatus was
constructed for research on the micromechanics
of DNA, DNA supercoiling, and
DNA-protein interactions. By joining DNA
molecules to magnetic beads and attaching
these tethers to the wall...
This paper reports the synthesis of an
azide-functionalized deoxynucleoside as a
precursor for azide-terminated oligonucleotides.
Also reported is the synthesis of an
acetylene-terminated precursor, which can
be used to make a diverse array of
silyl-protected acetylene-terminated small
molecule cores. Both of these precursors
serve as basic building blocks en route...
Magnetic resonance imaging (MRI) is a
powerful technique used in clinical
medicine and biomedical research to
conduct noninvasive imaging of tissues and
organisms. Chelated gadolinium is often
used as an MRI contrast agent to improve
the spatial resolution of these images.
Recently developed “smart” MRI contrast
agents respond to specific...
The need for high-performance, solid-state
H2 gas sensors is one research effort aimed
at enabling the future hydrogen economy.
Improving the gas-sensing properties of
semiconducting oxide materials such as tin
oxide, zinc oxide, etc., necessitates the
control microstructure and composition.
This study compares the effect of
dimensionality with the effect...
This research illustrates the modification of
an iodostyrene layer on a Si(111) surface
using a Sonogashira reaction. This was
accomplished by applying UV irradiation
(254 nm) to a hydrogen-passivated silicon
surface in a solution of iodostyrene in
benzene, followed by a Sonogashira
coupling between the iodine group from
iodostyrene and...
This research investigated the feasibility of
patterning with sol-gels using a nanofountain
probe in an atomic force microscope.
Two oxide sols — barium titanate and
cobalt ferrite — were used as inks in
patterning tests using fountain-pen
nanolithography (FPN). This was shown to
be a suitable method of depositing sol-gels...