Several phosphonate-functionalized molecular
squares have been successfully synthesized,
and the fabrication of multilayer films
on both conductive and semiconducting
platforms has been demonstrated. These
films were grown using the well-documented
zirconium phosphonate multilayer method.
The layer-by-layer growth rate is uniform.
Experiments suggest, however, that the
molecular squares adopt a semi-collapsed...
The development and applications of
organic/DNA molecules for the use of DNA
detection systems are reported here. In particular,
two different hybrids are synthesized:
DNA/polymer hybrids and small-molecule
DNA hybrids. DNA/polymer hybrids are especially
useful considering that their functionality
may be varied according to the polymer
selected. The hybrids are...
Recent research suggests that ultraviolet
illumination is essential for the creation of
monolayers of Undecylenic Acid Methyl
Ester (UDAME), as it is believed that the
UV illumination initiates the radical-chain
polymerization. Samples created without
UV illumination, however, also show signs
of a monolayer. In this study, samples were
analyzed using...
This research project explores two different
processes that can be used to pattern
organic molecules on silicon. In the first
process, hydrogen-terminated silicon surfaces
were anodized in nanometer scale with
a contact-mode atomic force microscope
(AFM). Anodization was done by applying a
positive bias voltage to the surface with
respect...
Feedback-controlled lithography (FCL)
enables atomically precise patterning of
individual molecules on the technologically
significant Si(100)-2 x 1:H surface. However,
because it is performed in an ultrahigh vacuum
(UHV) environment, FCL has thus far
been restricted to surface chemistries that
can be delivered in the gas phase. The present
research attempts...
Transmission and reflection diffraction
gratings were fabricated by micropatterning
polymers on transparent substrates and
drop-coating polymers onto etched silicon
wafers. Exposure of these gratings to three
nerve toxin mimics at very low concentrations
resulted in mimic sorption by the polymers,
changing the polymer’s refractive
index. As a result, the grating’s...
The effects of 13 nm Au colloid and 10 nm Ag
colloid on the growth of the yeast species
Saccharomyces cerevisiae were compared
to control samples cultured in a growth
media of yeast extract, bacto peptone, and
dextrose (YPD) to determine the toxicity of
nanoparticles. Growth curves were generated
for...
In modern medicine, physicians destroy
otherwise healthy tissues in patients’ bodies
because of the lack of site-target specificity
and sensitivity in detecting and attacking
cancerous cells. Many cancer patients are
left with the difficult task of weighing the
benefits against the harm of undergoing
current cancer treatments. Members of the...
Chemists and physicists have been interested
in the optical properties of metal nanoparticles
since the time of Michael Faraday.1
New approximation techniques for different
sizes and geometries have created renewed
interest in and investigation of these particles.
Many different arrays of particle extinctions
of various shapes and sizes have been...
While nanoscale device prototypes using
carbon nanotubes abound, no mass
production-scale technique exists for examining
properties of a batch of nanotubes.
Dielectrophoresis, on the other hand, has
received much attention in the press as a
method of separating and trapping particles.
In this research, a method of developing
mass production-scale...
Fullerene and inorganic fullerene-like nanotubes
are molecules with the unique geometry
of a single layer or multiple layers of a bulk
material oriented in a tube. These molecules
have novel mechanical properties and great
potential in experimental systems for nanotechnology
and nanodevices. The threedimensional
atom-probe (3DAP) microscope
is an atomic...
The effects of Ru, W, and Re on the temporal
evolution of the gamma prime precipitates in
a Ni-Cr-Al alloy were investigated by threedimensional
atom probe (3DAP) microscopy.
The spatial distribution of the gamma prime
precipitates in a model Ni-8.5Cr-10Al alloy
was investigated using atomic force
microscopy (AFM). We reported...
This study investigated the precipitation
strengthening of the binary Al-0.14wt% Sc,
0.16% Ti alloy system. Ingots of Al-2.1wt% Sc
and Al-4.68wt% Ti were melted together, and
the nucleation, growth, and coarsening of
precipitates were analyzed. The microstructural
evolution of the nanoscale L12 precipitates
phase was examined with Vickers
microhardness testing,...
Electron transfer theory predicts reorganization energy to be one factor that determines the electrochemical potential of a metal ion. This paper describes part of a study that aims to increase understanding of solvent reorganization energy in noncovalent systems by systematically varying the environment around a metal ion, specifically ruthenium. The...
Alzheimer’s disease (AD) is a progressive
mental disorder that affects 23 million people
worldwide. It is pathologically characterized
by amyloid plaques and tau tangles that
form in the brain. The hard, insoluble amyloid
plaques develop from the naturally
secreted amyloid beta peptide, which can
also assemble into toxic oligomeric forms...
Every year millions of Americans go to the
emergency room with symptoms of a heart
attack. More than half a million Americans
die each year of myocardial infarctions (MI)
caused by coronary heart disease (CHD).
CHD detection is currently limited to EKG
analyses of electrical signals generated by
the heart...
The optical properties of spherical gold
nanoparticles are calculated using classical
electrodynamics. The wavelength corresponding
to maximum extinction shifts to
longer wavelengths as the size of the
nanoparticle is increased. The influence of
higher-order multipoles is evident for large
nanoparticles, making the spectra more
complex. When the shell thickness of...
This paper explores the various approaches
to time-resolved single nanoparticle spectroscopy.
Due to the novelty of these types
of experiments, several difficulties arise in
creating a feasible physical setup capable
of imaging single nanoparticles less than
100 nm in size. The various difficulties in
setup and their attempted resolutions will...
Chemical vapor deposition was used to
synthesize CdS nanowires via the vaporliquid-solid
growth mechanism. After Ti/Au
contacts were patterned to the nanowires
using electron beam lithography, photoresponse
studies were conducted. A significant
response was observed when the
wires were exposed to visible light; this
occurred as electrons in the nanowires...
The performance of mixed-phase TiO2 was observed in an effort to test its practical use as
a semiconductor photocatalyst. Synthesis of mixed-phase TiO2, characterization using xray
diffraction analysis, monitoring testing using the gas chromatography-FID, and
testing gas phase reactor were four techniques used in this research to evaluate mixedphase
TiO2....
This project focused on the growth of Cu2O
nanocubes in microwells from nanoparticle
“seeds.” The seeds were first formed by the
reduction of copper sulfate with ascorbic
acid in the presence of the surfactant
poly(ethylene glycol) (PEG). Upon reaction
within the microwell, the seed solution
formed a larger single crystal....
In this study attention was focused on a
templated fabrication of Au nanotubular
structures that could carry a highly magnetic
entity such as cobalt. In brief, experimentation
was performed to create Co@Au
core-shell nanorods of different lengths. The
preliminary core-shell structures were first
characterized using x-ray diffraction (XRD),
scanning electron...
The purpose of this study was to select an
alloy with a low driving force for nucleation
for a more in-depth study of the nucleation
of γ’-precipitates. To do this, three Ni-Cr-Al
alloys were chosen close to the solvus line
of a Ni-Cr-Al phase diagram, ensuring low
supersaturation and therefore...
In this study liquid-phase nanolithography
(LPN) techniques using conductive atomic
force microscopy are investigated in order
to study properties of nano-patterned
organic molecules covalently bound to a
silicon substrate. Previous work has shown
that LPN in the inert organic solvent hexadecane
forms patterned features on
hydrogen-passivated Si(111). Due to hexadecane’s...
Monolayers on H-Si(111) were formed thermally
using decene and 10-bromodecene.
Samples were subjected to 100 percent
humidity in order to induce oxidation for
upwards of three weeks. The ability of
bromine to bind to the Si(111) and inhibit
oxidation through steric hindrance was
intended to be analyzed. Atomic force
microscopy...
The intention of this research was to investigate
the ink diffusion that takes place in
dip-pen nanolithography in order to better
understand how to enhance the possibilities
of nano fountain probes. Varying concentrations
of 16-mercaptohexadecanoic acid in
ethanol were used as ink in dip-pen nanolithography,
and the relationships between
contact...
This report describes the development of
bioorganic small-molecule complexes for the
directed assembly of functional nanomaterials.
In particular, it examines the synthesis of
small acetylene-based organic precursors for
attaching DNA to form DNA/organic hybrids.
This work continues previous studies
demonstrating how DNA/polymer hybrid
composites have sharper melting points than
DNA...
The bio-barcode assay is a nanotechnology-based
method for capturing and
detecting proteins. It shows extraordinary
sensitivity in detecting certain antigens at
extremely low concentrations, now without
the use of the polymerase chain reaction
(PCR). This assay uses disease identification
biomarkers that cannot be used in the
conventional assays of today....
Weak interactions in ligand-receptor
pairs are important in biological systems.
However, the energetics of these interactions
are often difficult to quantify for ligandreceptor
pairs. Weak interactions are a part
of reorganization energy, which plays a role
in electron transfer reactions. Under certain
conditions the rate of electron transfer
can be...
In this experiment, the optical properties
of several spherical nanoparticles were
observed. Particles were modeled using
Mie theory, a set of equations that calculate
the extinction coefficient of virtually any
spherical particle. Initially this theory was
used to model solid particles made of noble
metals. As time passed, its scope...
This work exploits the use of noble metal
nanoparticles to achieve sensitive and
selective detection of chemical and
biological analytes. The localized surface
plasmon resonance (LSPR) of these metal
nanoparticles is known to be sensitive to
shape, size, and the local environment.
Ag nanoparticles fabricated using the
nanosphere lithography (NSL)...
In this study, ligands modified to contain
a metal ion were synthesized and their
electrochemical properties were examined
alone and in the presence of a protein. We
chose to use avidin and biotin as a model
system. Probes have been developed in
which biotin is modified to coordinate to
a...
This project involved the study of Brownian
motion of polystyrene microspheres in the
presence of gravity and a one-dimensional
sinusoidal optical potential generated by
the interference of two laser beams. An
exponential relationship was observed
between applied laser power and particle
residence time of individual interference
fringes. Increasing laser power...
The aim of this research was to investigate
the use of atomic force microscopy (AFM)
for the high-resolution imaging of collagen
fibers in aqueous media. Collagen plays a
vital role in many processes in vivo, especially
in structural integrity, yet few studies
have used AFM to investigate the structure
of...
Many studies have focused on harnessing
the extraordinary optical properties of
noble metal nanoparticles for the development
of biological and chemical nanosensors.
Metallic nanoparticles emulate
surface roughness, facilitating the coupling
of light to surface plasmon polaritons. The
excitation of the plasmons enhances the
electromagnetic field near the surface so
that...
The need to improve sensing technology for
widespread application in everyday life is
fueling the development of diffraction-based
sensing, an optical sensing technique.
Selectivity and sensitivity issues must first
be resolved. Both selectivity and sensitivity
can be increased by using resonance conditions
— that is, using a probe wavelength
where...
The use of a variable resistor-capacitor
(RC) bridge circuit was previously reported
to be a viable solution to the spurious
contribution of fringe capacitance during
nanoscale impedance microscopy (NIM).
In this paper, a refinement of this technique
combined with standard NIM is presented
as an impedance characterization tool for
organic...
The effects of volumetric size-control
techniques on the photoinduced conversion
of silver colloids to triangular nanoprisms
were examined. It was hoped that through
the application of size-control techniques
on photocatalyzed reactions, a new method
of controlling particle dimensions could
be established. Initial work focused on
optimizing the synthesis procedure in...
Oligonucleotide-functionalized gold
nanoparticles (DNA-Au NPs) find
ubiquitous use in various biomolecular
detection schemes due to their unique
chemical and physical properties. This
study investigates the effects of nanoparticle
size and concentration of salt in
solution on the DNA loading of the Au NP
surface. The DNA loading studies are
performed...
Second harmonic generation (SHG),
a nonlinear optical tool, was used to
characterize DNA bound through a
chemical linker to the flat surface of a
hemispherical lens. Contact angle
measurements were used to guarantee
that the chemical linker did not hydrolyze
under experimental conditions. SHG
experiments followed the effects of salt...
Two-phase multiferroic nanostructures
have the potential to display magnetoelectricity
(ME) through interphase mechanical
coupling. Nanoscale ME-based technology
may lead to the next generation of computer
memory. In this research, soft electron
beam lithography (soft-eBL) was used to
fabricate submicron-sized structures of
cobalt ferrite (magnetostrictive) and barium
titanate (piezoelectric) as bottom...
Carbon nanotubes have been shown to
behave as very effective conductors and
semiconductors, but their electronic uses
are limited by how well metallic and
semiconducting nanotubes can be sorted.
Recent investigations have shown an
effective method of separating laser
ablation–produced carbon nanotubes by
electronic type. However, laser ablation
nanotubes are...
There is a continuing need for patterning
multifunctional materials to harness their
features and explore synergy among
diverse properties and phenomena. Soft
lithography, among various patterning
techniques, is a versatile method that can
generate inorganic patterns in a parallel
mode. Experimentation was performed
making use of flexible soft lithography to...
In this work, computational electrodynamics
is used to calculate extinction,
scattering, and local electric fields around
the transition metal nanoparticles. Rhodium
and ruthenium exhibit plasmon peak shifts
as a function of local refractive index
comparable to particles of silver and gold.1,2
In addition, the local fields calculated
indicate that Rh...
The purpose of this study is to characterize
the nanometer-scale structure of an Al2O3-
W-Ge multilayer utilizing x-ray reflectivity.
Attributes such as layer thickness, density,
surface, and interface roughness are
determined and explained. The reasons for
using this particular multilayer are also
reviewed, as well as the benefits to science...
Surface patterns, formed by the coassembly
of cationic-anionic amphiphiles into
cylindrical micelles, were analyzed. The
competition between electrostatic forces
and the net incompatibility χ arising from
the different chemical natures of those
oppositely charged amphiphiles resulted in
the formation of segregated domains. These
surface domains are not macroscopically
segregated due...
Amyloid-β oligomers, also known as
amyloid-β derived diffusible ligands
(ADDLs), have been implicated in numerous
studies as being a possible cause for
Alzheimer’s disease (AD). The goal of this
study was to investigate the kinetics of the
oligomerization of the monomer amyloid-β
(Aβ) into ADDLs in various ratios of
dimethyl...
Magnetic nanostructures are of great
interest as platforms for medical applications,
including biomedical imaging and
targeted cancer therapy. However, current
magnetic nanostructures are limited by
magnetic strength and insufficient
biocompatibility. In this research project,
significant progress was made to address
these confines, including 1) increasing
magnetic responsiveness by replacing the...
Antibiotin was labeled with colloidal Au
nanoparticles as a method of amplifying the
localized surface plasmon resonance
(LSPR) extinction maximum shift. This shift
allows for the monitoring of binding events
on the surface of nanosphere nithography
(NSL) fabricated silver nanoparticles. A
shift of +2.9 nm was observed for the
colloidal...
Weak, noncovalent interactions (dipoledipole
interactions, hydrogen bonding, and
Van der Waals forces) in ligand-receptor
pairs play a very important role in living
systems. A new way to study these
interactions is by using electron transfer
theory. The rate of electron transfer
between redox centers is dependent on
several factors, including...
Weak, noncovalent interactions (dipoledipole
interactions, hydrogen bonding, and
Van der Waals forces) in ligand-receptor
pairs play a very important role in living
systems. A new way to study these
interactions is by using electron transfer
theory. The rate of electron transfer
between redox centers is dependent on
several factors, including...
Carbon nanotubes (CNTs) are highly
promising in the miniaturization of
electronic devices. However, there are
currently many limitations in mass
producing devices that involve the
application of CNTs, one of which is the
ability to physically pattern CNTs in specific
locations on a wafer, which is what this
study aims...
In this study, particle sorting and transportation
in Brownian liquids were explored by
translating an optical standing wave. The
standing wave is produced by crossing two
coherent beams of light, and determining
the resulting period by the angle of the
intersection. Adjusting the period and
velocity of wave ridges allows...
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...
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...
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 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 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...
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...
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...
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...
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...
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...
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....
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...
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...
Concern about maximizing and improving heterogeneous catalysis has
grown because it is used in a variety of applications. This study focused
on the effect single-walled carbon nanotubes (SWNTs) had on titanium
dioxide (TiO2) catalysis. Two different forms of TiO2, rutile and anatase,
were combined with SWNTs in heterogeneous mixtures and...
Semiconductor oxides are important materials in gas-detection systems
and can be improved by enhancing the sensitivity and selectivity of
oxide sensors to specific gases. This research investigates the effect of
palladium dopant (Pd) on the hydrogen gas-sensing ability of ZnO 2-D
nanostructures. Photolithography was used to pattern electrodes on
various...
The aim of this research is to investigate the pH effect on the assembled
nanostructures of peptide amphiphiles (PAs). Controlling the sizes and
shapes of these assembled nanostructures is of great importance for
their ultimate applications in drug delivery, tissue engineering, and
regenerative medicine. A complete characterization of these nanostructures...
Bone-related problems have always been a concern in the medical field,
particularly how to heal and rebuild bones more rapidly when injuries
occur. A path to solving such problems might be to examine the
processes when bone develops in nature. This project aims at discovering
the chemical reactions that occur...
The formation of covalently grafted polymer brushes on silica (SiO2)
nanoparticles was achieved by surface-initiated reversible additionfragmentation
chain transfer (si-RAFT) polymerization. RAFT initiator
was first attached onto the surface of silica nanoparticles and then
examined by ultraviolet-visible spectroscopy (UV-vis) analysis. From the
resulting RAFT initiator-modified SiO2 nanoparticles, polymer chains
can...
Polymer nanoparticles (PNPs) were formed from amphiphilic diblock
copolymers consisting of a hydrophilic block with pendant polyethylene
glycol tosylate (PEG-OTs) groups and a hydrophobic block with pendant
terthiophene (TTT) groups. The resulting PNPs were characterized
using dynamic light scattering (DLS) and transmission electron
microscopy (TEM) to determine size, shape, and...
The formation of organic layers on hydrogen-passivated silicon (HPS)
surfaces via (UV) ultraviolet treatment was completed for three styrene
derivatives with different conjugated lengths. The styrene molecules
were synthesized and characterized using nuclear magnetic resonance
(NMR) spectroscopy and gas chromatography-mass spectrometry
(GC-MS). Layer formation on silicon was then accomplished through...
In the field of clinical diagnostics, biosensors are used to identify genetic
disorders by hybridizing a surface-bound DNA sequence with the
patient’s DNA. To further improve biosensor design, two nonlinear
optical techniques, sum frequency generation (SFG) and second
harmonic generation (SHG), were used to probe the orientation,
chirality, and surface...
Small, soluble, self-assembling peptide Aβ-oligomers, known as ADDLs
(amyloid-derived diffusible ligands), accumulate in the Alzheimer’s
disease (AD) brain as Aβ 12-mers and are thought to contribute to AD
neuropathological conditions. Unlike plaques, which were once thought
to cause neuronal death due to insoluble amyloid plaque deposits,
ADDLs initiate abnormal changes...
Semiconductor nanowires show promise for application in nanoscale
electronics, but the difficulty of forming low-resistance ohmic contacts
provides a challenge to their implementation. To improve the electrical
performance of lithographically defined nickel contacts, nickel-silicide/
silicon axial nanowire heterostructures were formed by controlled
partial silicidation. Prior to annealing, two-terminal silicon nanowire...
"This paper describes the development of an efficient transfection
vehicle for nucleic acids using surface-functionalized gold nanoparticles
(AuNPs) with a mixed-monolayer of biological molecules—a hybrid
approach that combines two previously investigated models. The
objective is to improve upon previously described nanoparticles used to
introduce nucleic acids to cells—oligonucleotide-functionalized AuNPs
and...
This paper reports the syntheses of acetylene-terminated smallmolecule
cores. Also reported are successful attempts at “click”
coupling the core molecules with azide-terminated oligonucleotides to
construct stable small-molecule DNA hybrids (SMDH). Once these
click-based small-molecule DNA hybrids are formed, melting studies
will be done that study how the geometry of SMDH...
The swelling and deswelling behavior of poly(methacrylic acid) (PMAA)
thin films and the permeability of poly(styrene) (PS) membranes was
investigated using quartz crystal microbalance and ellipsometry.
The system consisted of either homopolymer PMAA film or diblock
poly(methyl methacrylate)-poly(methacrylic acid) (PMMA-PMAA)
brushes with a hydrophobic PS membrane capping layer. Results show...
This study examined the invasiveness of nanofountain probes (NFP)
when used as a transfection tool for single-cell research. For comparison,
the damage caused to cells by more commonly used commercial
atomic force microscope (AFM) probes was also studied. Forces were
applied to cells at increasing levels using both probes, and...
Cadmium selenide (CdSe) quantum dots have low conductivity upon
synthesis with the original capping ligands. The conductivity can be
altered by the addition of other ligands. Thiols, amines, and carboxylic
acids, as well as other functional groups, have been shown to improve
conductivity in quantum dot films. This investigation describes...
This paper investigates the use of self-assembled monolayers
(SAMs) to optimize the localized surface plasmon resonance (LSPR)
biosensor for disease detection. Various experiments were done
with 1-(9-mercaptononyl)-3,6,9-trioxaundecan-11-ol (TDT) and
heptaoxatricosanoic acid (HSA), a new SAM; these included a solvent
study to determine refractive index sensitivity and nonspecific binding
and specific...
Under the correct conditions, aluminum can be anodized in an electrochemical
cell to produce hexagonally ordered arrays of nanoscale
pores. This study examines how adding the chemicals methanol and
acetic acid to a typical anodization solution alters pore-growth patterns
across the surface oxide layer. The existence of the unique pore-growth...
Thermoelectric materials, which convert heat energy to electrical
energy, may become increasingly important in the world’s energy
situation. Through the inclusion of nanoscale features embedded within
a thermoelectric bulk material, it has been shown that a corresponding
decrease in lattice thermal conductivity results in an enhanced
thermoelectric figure of merit,...
Alzheimer’s disease (AD) is one of the most common forms of dementia,
with no current definitive premortem diagnosis. Amyloid beta-peptide
derived diffusible ligands, known as ADDLs, have become a key link in
the AD specificity for memory loss and are a potential biomarker for AD.
In order to develop an...
Neurons are difficult to manipulate experimentally. Most transfection
reagents used for gene silencing are neurotoxic, and the postmitotic
state of neurons prevents the effective use of viral vectors. This study
demonstrated the delivery of antisense DNA against target genes by
gold nanoparticle oligonucleotide complexes (GNOs) in primary cultures
of rat...
Magnetic nanostructures (MNS) have become the subject of intense
interest due to their superparamagnetic properties and consequently
their potential uses in medical diagnostics and therapeutics. In this
study, monodisperse magnetite MNSs were synthesized via thermal
decomposition of iron(III) acetylacetonate and transferred to aqueous
solution using 11-aminoundecanoic acid as the surfactant....
With the advent of a variety of novel nanometer-scale diagnostic techniques such as DNA micro- and nanoarrays, increasing focus has been placed on developing methods to quickly and accurately create these nanometer scale patterns. One promising technique for depositing DNA, proteins, and other liquid molecular "inks" with submicron resolution is...