applied physics/nanotechnology honours research projects 2015 · applied physics/nanotechnology...
TRANSCRIPT
i
Applied Physics/Nanotechnology Honours Research Projects 2015 Supervisors Project Description Page
Cuong Ton-That, Matthew Phillips
Characterisation of nitrogen acceptors in zinc oxide nanowires 1
Cuong Ton-That, Huu Hao Ngo Optimisation of Fe nano- and micro-particles for the removal of heavy metals in water
2
Matthew Arnold, Chris Poulton
Modelling gap plasmons for optimal energy concentration 3
Matthew Arnold, Milos Toth Simulating the effect of bollard lattices on bacterial path-following 4
Angus Gentle, Matthew Arnold Nanocomposites for directional emission control 5
Annette Dowd, Shaoli Zhu Enhancement of Raman spectroscopy using silver nano-stars 6
Annette Dowd, Stella Valenzuela, Linda Xiao
Optical spectroscopic probing of biological nanomachines: elucidating the structure of CLIC proteins in cell membrane models
7
Michael Cortie, Annette Dowd
Precipitation of intermetallic phases from metastable (Pt,Ag) thin films 8
Milos Toth, Charlene Lobo Directed and emergent phenomena in chemically-assisted charged particle beam nanofabrication
9
Igor Aharonovich, Olga Shimoni Development of novel bio-markers based on fluorescent nanocrystals 10
Igor Aharonovich, Mike Ford Investigation of optically active 2D materials 11
Igor Aharonovich, Matthew Arnold
Coupling single emitters to plasmonic nanostructures 12
Igor Aharonovich, Milos Toth, Olga Shimoni
Controlled growth of diamond nanostructures 13
Mike Ford Designing 2D materials for the future 14
Mike Ford Super-atom materials 15
Michael Braun Heart displacement in free-breathing MR-PET image data 16
Chris Poulton Nonlinear phononic interactions in nanophotonic structures 17
Andrew McDonagh
New Metal and Metal Oxide Core/Shell Nanoparticles 18
Zhimin Ao, Guoxiu Wang
Atomistic simulations on graphene-based materials for hydrogen storage and in Li-ion batteries
19
Hao Liu
Novel nano-structured materials for high power energy storage 20
Charles Cranfield, Annette Dowd, Stella Valenzuela
Creating improved electrodes for cochlear and vision implants. 21
ii
1
Characterisation of nitrogen acceptors in zinc oxide nanowires
Cuong Ton-That, Matthew Phillips
Zinc oxide (ZnO) nanowires have the capability to provide the key for many nanodevice applications
due to its versatile optical and electronic properties. ZnO also possesses properties superior to its
chief competitor, Gallium Nitride (GaN) that has been widely used in light emitting diodes in recent
years. Like nitride materials, benefits of ZnO can only be realised once a reliable acceptor and
associated fabrication methods have been established.
Our recent studies have shown that ZnO nanowires doped with nitrogen by plasma annealing exhibit
the characteristics of a shallow acceptor. However, the exact chemical origin of the acceptor has not
been established. This project involves the growth of ZnO nanowires with prescribed defect
properties using chemical vapour deposition. Doped ZnO nanowires will be achieved by plasma
annealing in appropriate gaseous environments. The relationship between plasma processing
conditions and optical emissions associated with the acceptor will be investigated by advanced
microscopy and synchrotron techniques.
ZnO nanowires grown at UTS
Techniques
Plasma processing, electron microscopy, cathodoluminescence, photoluminescence, Raman, x-ray
diffraction, energy dispersive x-ray analysis
2
Optimisation of Fe nano- and micro-particles for the removal of heavy
metals in water
Cuong Ton-That, Huu Hao Ngo
Fe particles are good adsorbents of heavy metals and metal-ligand complexes in water. Extensive
studies in Centre for Technology in Water and Wastewater (CTWW) in FEIT have proved that Fe is an
economically feasible material for the efficient removal of Pb, Cu and Zn from wastewater; however
at present the exact mechanism of aqueous contaminant removal is unknown and thus the process
cannot be optimised. It has been recognised that if the particle size and surface chemistry can be
controlled, this method is capable of removing heavy metals to much lower levels than the current
achievable level and over a wider pH range. This project involves the production of Fe nano- and
micro-particles by ball milling, the particles are thermally treated in plasma to control the surface
chemistry systematically. The processed materials will be analysed by electron microscopy, x-ray
microanalysis, Brunauer–Emmett–Teller (BET) and inductively coupled plasma atomic emission
spectroscopy (ICP-AEP) to investigate the relationship between their surface and morphological
properties and the removal efficiency of heavy metals.
This is a collaborative project that brings together interdisciplinary expertise from two research
strengths within UTS.
Techniques
Electron microscopy, x-ray diffraction, energy dispersive x-ray analysis, BET, ICP-AEP, plasma
processing, ball milling
3
Modelling gap plasmons for optimal energy concentration
Matthew Arnold, Chris Poulton
Gap plasmons concentrate energy particularly strongly, which could be usefully exploited in
detection and energy conversion applications. While there is extensive literature on the gap
plasmons where a single metal is present, there is comparatively less on combinations of metals.
Use of dissimilar metals offers additional flexibility in tuning and possibly other advantages. The aim
of this project is to investigate a new technique to simulate the field enhancement between pairs of
common metals, and ideally develop a model that could be used to predict the optimum metals for a
given application.
Plasmon confinement between metal resonators
Techniques
This is a computer simulation project – some knowledge of computer simulations and optical
resonators would be a definite advantage. The simulations will be carried out using existing
implementations of solvers such as DDA & BEM. These large scale calculations will be run remotely
on the UTS cluster with SSH & PBS.
4
Simulating the effect of bollard lattices on bacterial path-following
Matthew Arnold, Milos Toth
Collective motion emerges in systems such as crowds of people and bacterial colonies, and the
ability to control this motion is often desirable. Simple models for these systems have given insight
into why this behaviour occurs: for example it has been suggested that bacteria exhibit path-
following behaviour through chemical signalling (much like ant trails). One possibility for disrupting
bacterial activity is to insert barriers that establish controlled paths. The aim of this project is to use
simulations to understand how lattices of barriers might affect bacteria, by quantifying how path-
following metrics vary in response to lattice spacing and symmetry.
Sketch of bacterial pathfollowing in an artificial lattice
Techniques
This is a computer simulation and will require familiarity with computational physics and
programming, especially in Matlab. It will use an established stochastic particulate model, with
some programming required to setup up the barriers. If time or inclination permits, conversion to a
continuum fluid model could be undertaken. Learning to use a batch system such as PBS would be a
desirable outcome of this project.
5
Nanocomposites for directional emission control
Angus Gentle & Matthew Arnold
Improved absorption and emission on opaque materials is important for improving the efficiency of
photovoltaics. In particular, thermophotovoltaics (TPV) should maximize absorption on the “hot”
side and confine emission around the bandgap of the photovoltaic material. Mixtures of metals and
dielectrics offer a useful way to tune this emission – producing them requires attention to the
mutual wettability of the materials. Additionally the directionality of emission is important, and this
can be controlled either via multilayer structures or by production of vertically oriented
nanostructure. The aim of this project is to systematically produce a series of emission control
coatings (for example by varying the metal-dielectric deposition time or the deposition angle) and
characterize the angular emission.
Sketch of directional emission from a nanostructured coating
Techniques
The films will be grown either by sputtering or e-beam deposition using existing semi-automated
equipment. The optical properties will be characterised on a variety of equipment such as the
spectrophotometer, ellipsometer & emissometer. Some development of protocols and/or additions
to optical equipment could be performed by the student so it would particularly suit someone with
good instrumentation development skills. The structures will be characterized using SEM and/or
TEM cross-section.
6
Enhancement of Raman spectroscopy using silver nano-stars
Annette Dowd, Shaoli Zhu
Raman spectroscopy is a useful technique that can provide information on the structure or
composition of a sample. The Raman signal can be massively amplified if the analyte is placed on a
particle or surface that can undergo a plasmon resonance with the Raman probe laser. This
phenomenon is known as Surface Enhanced Raman Spectroscopy (SERS) Here we will investigate the
degree to which SERS can be carried out on arrays of silver nano-stars (already) prepared using
electron beam lithography. One or more suitable Raman probe molecules will be used and the
Raman signal carefully mapped using as many different wavelengths of Raman probe laser as are
available. The work will be supported by numerical simulations of the electric field intensity around
the nano-particles (this part co-supervised by Prof. M Cortie). The purpose of the work is to
determine how much enhancement occurs, where exactly on the nano-star geometry the
enhancement occurs, and whether the maximum enhancement is at the plasmon resonant
wavelengths or (as recently reported in the scientific literature) at wavelengths that are significantly
red-shifted from the resonances.
Techniques
Raman microscopy and mapping, Surface Enhanced Raman Spectroscopy, numerical simulations of
electromagnetic fields generated by light, scanning electron microscopy, atomic force scanning
probe microscopy
7
Optical spectroscopic probing of biological nanomachines: elucidating the
structure of CLIC proteins in cell membrane models
Annette Dowd, Stella Valenzuela, Linda Xiao
Raman spectroscopy is a potentially powerful tool to monitor modification in the lipid bilayer and
also the protein structure. Characteristic vibrations of chemical bonds can be subtly changed by their
nanoscale local environment, e.g. the frequency associated with the peptide bond depends on
whether it is situated in an alpha-helix or a beta-sheet structure. Raman spectroscopy can
interrogate these chemical bonds in a noninvasive way by using only a tightly focused laser beam.
The aim of this project is to add to knowledge about the structure of the CLIC protein machinery and
its insertion into lipid bilayer membranes using a novel application of Raman microspectroscopy.
This student will study the effect of cholesterol on the lipid structure, protein structure and its
insertion. The student will also develop the Raman technique by investigating different types of
membrane preparation (liposomes, single tethered layers etc) and the use of nanostructured SERS
substrates for signal enhancement.
This multidisciplinary project will be undertaken in PAM, CFS & MMB labs. Opportunities will be
available to access state-of-the-art equipment at the Vibrational Spectroscopy Facility at the
University of Sydney. (http://sydney.edu.au/science/chemistry/spectroscopy/index.shtml)
Techniques
Raman spectroscopy, Confocal microscopy, Magnetron sputtering, SEM, perhaps multivariate data
analysis depending on interest of student.
8
Precipitation of intermetallic phases from metastable (Pt,Ag) thin films
Michael Cortie, Annette Dowd
Platinum electrodes are the preferred option for medical implants that cause neural stimulation.
However, pure platinum is quite soft. In this project we investigate whether Pt can be hardened by
additions of Ag. A side-benefit is that Ag is a potent bactericide, which may be useful in the medical
implant context. Thin films of Pt-Ag alloys will be prepared by physical vapour deposition and then
carefully characterized to determine their crystal structure, mechanical properties and solid-state
phase transformations. A key factor is whether the material remains in the desirable face centred
cubic structure or whether it transforms to brittle intermetallic compounds.
Techniques
magnetron sputtering, X ray diffraction, Rietveld data analysis of diffraction patterns,
crystallography, kinetics and thermodynamics of phase transformations, microscopy including SEM
and (maybe) TEM
9
Directed and emergent phenomena in chemically-assisted charged particle
beam nanofabrication
Milos Toth, Charlene Lobo
Electron and ion beams can be focused down to ~1 nm and used for additive and subtractive
nanofabrication. The techniques typically employ a coincident pair of electron and Ga ion beams in a
vacuum chamber that contains a fabrication precursor gas (Fig. 1(a)). Deposition is achieved by
irradiating a substrate in the presence of a gas that contains the atoms of interest, while chemical
dry etching employs precursors such as XeF2 which are decomposed by a beam into species (e.g. F*)
that react with and volatilise a solid substrate. The beams primarily cause the dissociation of surface-
adsorbed (rather than gas-phase) precursor molecules, thereby leading to highly localised additive or
subtractive `3D printing' with a spatial resolution of ~10 nm (Fig. 1(b-c)). In addition, self-ordered,
`emergent' growth of complex, 3D nanostructures can arise from non-linear interactions between a
number of physical and chemical processes such as sputtering, self-masking, adsorbate dissociation,
and mass transport of molecular fragments and intact precursor molecules.
The present project will advance present understanding of the basic mechanisms behind chemically-
assisted charged particle beam fabrication. The student will have the option to achieve this
experimentally, and/or by advancing existing, state-of-the art computational modeling techniques.
Experimental work will be focused on identifying and elucidating basic mechanisms behind directed
and emergent growth phenomena. Theoretical work will involve the development of rate equation
algorithms for predictive models of material growth and processing rates.
Figure 1: Schematic illustrations of: (a) a coincident electron-ion beam system; (b) 3D printing by a focused scanned ion beam and (c) a
stationary defocused, top-hat electron beam; and, (d) emergent, bottom-up growth under a stationary beam.
Techniques
Electron and ion beam microscopy, scanning probe microscopy and/or computer models of EBIED
implemented in MatLab, Mathematica and/or the C++ programming language.
Ga+
subs
trat
e
e-
gas injector
b) c) d) a)
10
Development of novel bio-markers based on fluorescent nanocrystals
Igor Aharonovich, Olga Shimoni
The goal of the project is to demonstrate use of nanodiamonds as bio-markers for biological tagging
and labelling. Nanodiamonds are biocompatible and host bright color centers which can be used as
efficient bio labels.
The project goals are to incorporation of the nanodiamonds into biological media – e.g. cells. Several
challenges will be addressed by the students during the project: prevention of nanodiamonds’
agglomeration, investigation of emitter photostability in small particles, characterization of
nanodiamonds in cells.
This multidisciplinary project will provide the student exposure to both optical and biological
sciences. The student will have access to the newly established nanophotonics laboratory that
includes a confocal microscope for the photoluminescence measurements as well as the opportunity
to learn basic biological processes and work with cells.
Techniques
Confocal microscopy, Scanning Electron Microscopy, biological sample preparation.
11
Investigation of optically active 2D materials
Igor Aharonovich, Mike Ford
Two dimensional materials (2D) such as graphene attract a lot of attention due to their unique
photophysical properties. Recently, it was shown that single layers of di-chalcogenides (MoS2/WS2)
are optically active materials that exhibit bright florescence.
This project will be focused on understanding the optical properties of these materials. The student
will investigate defect generation in these materials, perform high resolution spectroscopy and
measure photon statistics.
The student will have access to the materials and will investigate novel growth methods of single
layered materials. The newly established nanophotonics laboratory that includes all the required
optical gear (single photon detectors, spectrometer, low temperature cryostat etc) will be used for
characterization. The student will also get experience in nanomaterials characterization using SEM,
AFM and will pursue basic nanofabrication processes.
Techniques
Confocal microscopy, Scanning Electron Microscopy, chemical vapor deposition,
Cathodoluminescence, low temperature spectroscopy.
12
Coupling single emitters to plasmonic nanostructures
Igor Aharonovich, Matthew Arnold
The goal of the project is to develop robust methods to couple single emitters to plasmonic
nanostructures. One of the main challenges in single photon emitters is their relatively low
brightness. Through coupling to plasmonic resonators, the emission is enhanced and the excited
state lifetime is reduced.
The project will involve characterization of single photon emitters using a confocal microscope and
Hunbury Brown and Twiss interferometer. Once the emitters are selected, metal nanoparticles such
as gold and silver will be deterministically positioned in a close proximity to the emitters. To
optimize the coupling, various parameters including emitter’s distance, dipole orientation and the
plasmonic medium would be varied. If time permits, modeling of the system will be conducted to
understand the underlying photophysical processes.
The student will have access to the newly established nanophotonics laboratory that includes all the
required optical gear (single photon detectors, spectrometer, low temperature cryostat etc). The
student will also get experience in nanomaterials characterization using SEM, AFM and will pursue
basic nanofabrication processes.
Techniques
Confocal microscopy, Scanning Electron Microscopy, cathodoluminescence, low temperature
spectroscopy.
13
Controlled growth of diamond nanostructures
Igor Aharonovich, Milos Toth, Olga Shimoni
The goal of the project is to develop growth of diamond nanoparticles and films using the newly
established microwave assisted chemical vapour deposition (CVD) reactor at UTS. One of the main
challenges will be controlling the density of the crystals, their final size and quality. A methodology
to incorporate fluorescent color centers into the diamond will be investigated as well.
The student will utilize the CVD reactor at UTS as well as the reactive ion etching system and
photolithography tools. This project will provide a thorough understanding into controlled growth of
diamond and fundamental nanofabrication techniques that will enable exposure to “real world”
technologically important processes. The student will also get experience in nanomaterials
characterization using SEM, and optical confocal microscopy.
Techniques
microwave CVD, photolithography, confocal microscopy, Scanning Electron Microscopy,
cathodoluminescence.
14
Designing 2D materials for the future
Mike Ford
Computational materials science has been used for some time to describe the properties of existing
materials, for example the electronic properties of silicon. The future is using computers to design
new and novel materials that currently don’t exist (Heine Frontiers in Materials, 1, pp1, 2014).
Progress in computing hardware and software is bringing this goal nearer all the time. Add to this
the recent advances in understanding 2-dimensional (2D) materials (materials that are only one or a
few atoms thick, such as graphene, then the future becomes very interesting.
The aim of this project is to combine more traditional computational materials science with machine
learning methods to predict new hybrid materials that are yet to be made experimentally. A range of
potential 2D materials have already been identified (Lebegue et al Phys Rev X, 3, pp031002, 2013)
and will be the basic building blocks for our hybrid materials, for example alternating layers of MoS2
and graphene. Machine learning techniques will allow us to work out how to combine these
building blocks to make materials with the new functionalities. For example, combining the
excellent conductivity of graphene with the optical properties of MoS2.
Techniques
Computer based materials programs for calculating the properties of materials (eg VASP or SIESTA),
and machine learning neural network programs. We would most likely use the computer packages
VASP and SIESTA. Depending upon interest there is also opportunity to write your own programs for
analysis of the data. High performance computing facilities.
15
Super-atom materials
Mike Ford
Conventional solid materials are made from collections of atoms, for example NaCl is binary solid
compound made up of Na and Cl atoms bound to each other due to charge transfer between the
two atoms forming ionic bonds.
Recently the first in a whole new class of solid-state materials was produced (Roy et al, Science 341,
pp157 2013). In this material clusters of atoms are the basic building blocks once again held
together by charge transfer and Van der Waals bonds. This opens up the possibility of creating
whole families of new materials where properties and functionality can be controlled by varying the
superatom building blocks.
In this project we will use computer simulations to look at the atomic properties of these new
materials. The starting point would be those few materials already successfully synthesised
experimentally, with the aim of predicting new super-atom materials.
Techniques
Computer based materials simulations. We would most likely use the computer packages VASP and
SIESTA. These are both implementation of Density Functional Theory and solve the Schroedinger
equation. Depending upon interest there is also opportunity to write your own codes for analysis of
the data. High performance computing facilities.
16
Heart displacement in free-breathing MR-PET image data
Michael Braun
In free-breathing positron emission tomography (PET) or single photon emission computed
tomography (SPECT), the image is acquired over a period extending over multiple respiratory cycles.
As the patient breathes, the thorax expands and contracts anisotropically, the diaphragm pushes up
on the thoracic cavity and the heart moves largely in the longitudinal direction. The heart
displacement causes substantial blurring that would not be corrected by ecg gating. Furthermore,
the cardiac displacement due to breathing is substantially less regular in frequency and amplitude
than the cardiac cycle. In a dual system, the PET or SPECT scanner is coupled with an anatomical
modality, such as the MR imaging system. Recent developments (M Uecker et al., NMR in
Biomedicine, 2010, see also http://en.wikipedia.org/wiki/File:Real-time_MRI_-_Thorax.ogv) allow
MR to capture thoracic images with temporal increments much smaller than the cardiac cycle. The
project will investigate the capture of cardiac displacement from the high spatial and temporal
resolution and application of the respiratory model to the complementary SPECT/PET data. Of
particular interest is the decoupling of the blurring caused by the cardiac displacement from the ecg
gated data.
The project will be carried out in collaboration with the Institute of Nuclear Medicine at the
University College London. It will suit a student comfortable with computational modelling (e.g. in
Matlab) and interest in medical imaging.
Techniques:
The student’s computational work will be implementing using a scripting language, such as Matlab
or IDL. Image data will be provided by collaborators at the University College London.
17
Nonlinear phononic interactions in nanophotonic structures
Chris Poulton
The project will be part of CUDOS, the ARC Centre of Excellence for nanophotonics, and involve
collaborating with researchers from UTS, Macquarie University and the University of Sydney. The
main focus of this research is on the theoretical and computational investigation of the nonlinear
interaction between acoustic and optical waves in integrated nanophotonic structures. These new
“phononic chips” promise breakthrough applications in high-speed optical processing and sensing,
and have recently been used in fundamental studies of “slow” and “fast” light. The honours project
will concentrate on using new theoretical and numerical techniques to model the complex
interaction between optical and acoustic waves in new materials and in microstructured devices.
The specific task will be to model the dynamics of the interaction in chalcogenide nanowires, first by
computing the otpical and acoustic modes and then using coupled mode theory to simulate the
dynamics. The optical field will lead to vibrations in the waveguide, which will function as a tuneable
long-period grating, which can be used for filtering or for the modification of optical pulses. An
analysis of the performance, feasibility and optimization of this grating structure will form the
capstone of this project.
This project requires good knowledge of electromagnetic theory and will involve some
programming.
Techniques
Electromagnetic theory, elasticity theory, programming using Matlab and COMSOL
18
New Metal and Metal Oxide Core/Shell Nanoparticles
Andrew McDonagh
In this project, nanoparticles containing metal oxide cores coated with gold will be investigated. The
particles will then be examined by ablating them with a laser and analysing the masses of the
ablated materials under various conditions.
Nanoparticles made of gold have proven to be extremely valuable as probes to visualise important,
individual features within biological specimens. However, if multiple targets are to be imaged, then a
solid gold particle provides no means of distinguishing between the targets. As a solution to this
problem, core−shell structures may be used as extremely sensitive bio-imaging probes if they
possess an appropriate metal oxide core and gold shell.
Project outcomes: This project will result in new nanoparticles and new knowledge about the laser
ablation of the new particles under various conditions. The particles may be applied to biological
material to enable imaging of molecule/particle interactions as well as their interaction with light.
Techniques
Nanoparticle synthesis, molecular synthesis, measurement of optical properties, laser ablation, mass
spectrometry, scanning electron microscopy.
19
Atomistic simulations on graphene-based materials for hydrogen storage
and in Li-ion batteries
Zhimin Ao, Guoxiu Wang
Graphene was experimentally fabricated for the first time in 2004 and was found with excellent
electrical, mechanical and thermal properties. Graphene has shown promising applications as ultra-
sensitive gas sensors, transparent electrodes in liquid crystal display devices, large capacity
electrodes in Li-ion batteries and hydrogen storage materials. In this project, to further explore
graphene applications in electronic devices, especially in Li-ion batteries, and hydrogen storage
materials, atomistic simulation method (using Materials Studio software and other first principles
calculation software) is used to predict the electronic and magnetic properties of graphene in the
presence of substrates and different kinds of defects, the interaction between hydrogen or Li-ion
and graphene related materials, then to determine the hydrogen storage behaviors or the
performance of Li-ion batteries.
Hydrogen storage in 3D graphene structure
Techniques:
Materials Studio software and other first principles calculation software.
High performance computing cluster in UTS, and National computing infrastructure in Canberra.
20
Novel nano-structured materials for high power energy storage
Hao Liu
Greenhouse gas emissions from the consumption of fossil fuels are causing disastrous climate
change and global warming. The research and development of electric vehicles to replace
conventional vehicles has emerged as a solution to this imminent problem. The progress of battery
technology plays a key role in the development of electric vehicles. This proposed project addresses
the issues by the development of innovative nano-structured materials for next generation batteries
with high capability, high power density and excellent retention. In this project, a series of novel
structured will be synthesised from wet-chemistry method. The resultant nano-structured materials
will be characterised by advanced instrumental analyses such as scanning electron microscopy
(SEM), transmission electron microscopy (TEM), nitrogen adsorption, small angle X-ray diffraction
(SAXRD), and small-angle X-ray scattering (SAXS) to determine the micro-structure. Their
electrochemical performance will be investigated for high-power energy systems, including lithium
ion batteries, sodium ion batteries, lithium sulphur batteries and lithium air batteries. In particular,
in situ analyses (XRD & TEM) will be conducted to investigate the working principle of energy storage
systems. This project will benefit UTS and Australia in the research forefront of nanotechnology,
materials engineering, energy storage and applied chemistry.
Techniques:
Material synthesis, characterization and electrochemical measurement.
Internal: Furnace, oven, microwave oven, glovebox , X-ray diffraction (in situ), Scanning Electron
Microscope, Atomic Force Microscopy, Transmission electron Microscopy. (Faculty of Science)
External: Neutron & Synchrotron X-ray diffraction (in situ), Transmission electron Microscopy.
(ANSTO, Australian synchrotron, USyd)
21
Creating improved electrodes for cochlear and vision implants.
Charles Cranfield, Annette Dowd, Stella Valenzuela
This project aims to actually get cells to grow adjacent to gold electrodes using tethered bilayer lipid
membranes. By investigating ways to grow cells directly onto gold we hope to demonstrate how to
improve electrode design in cochlear and retinal implants.
By anchoring cells directly onto the electrodes will enable improved resolution of electrically
implanted devices such cochlear and retinal implants. Currently, implanted stimulatory electrodes
are hampered in that they overstimulate too many cells at once.
The student will grow murine cardiomyocyte like cells (HL-1 cell line) cells (which are electrically
excitable) to near confluence on electrodes that have been chemically coated with tethering
chemistries provided by SDx Tethered Membranes Pty Ltd. Using electrical impedance spectroscopy
the student will determine if cells directly adjacent to the electrodes are being stimulated.
If time permits, the student will also demonstrate that the cells are being stimulated using
membrane potential fluorophores in conjunction with confocal microscopy.
Techniques: cell culture, impedance spectroscopy, confocal microscopy
Note: this project involves PC1 cell culture which will require that the student has or can quickly
develop an aptitude for biology (with assistance from supervisors). The Applied Physics and
Nanotechnology degrees require that the results can be explained to physicists.