Tell us what you think of PERSPECTIVES! - IMRE - A*Star

Research, Development and Commercialisation
MICA (P) 051/03/2011 • ISSN 0219-1830 JULY 2011
CORPORATE NEWS
Smart biomaterials
from IMRE
Institute of
Materials Research
and Engineering
www.imre.a-star.edu.sg
RESEARCH AWARDS OUTREACH
UPCOMING EVENTS
Record-breaking
electroluminescence
from blue-light
emitting materials
IMRE’s synthetic cell
membranes is one
of the top Asian
innovations
IMRE’s synthetic cell membrane technology
is one of the top Asian innovations
Dr Madhavan Nallani’s work on synthetic cell membranes that could help reduce cost and
speed up the development of medicines and drugs is one of 12 finalists in the Wall Street
Journal’s Asian Innovation Awards 2011.
Schematic representation of artificial
membrane.
They may look and act like
natural human cell membranes
but the synthetic cell membranes
Online
Survey
invented by Dr Madhavan Nallani
have more advantages compared
to the real thing. IMRE’s patented
synthetic cell membranes can
be made-to-order, are easier
to maintain in a laboratory
environment and do not require
the lengthy preparation that
comes with working on live cell
membranes. The synthetic cell
membranes mimic the natural
functions of live cell membranes,
such as interacting with drug
molecules and antibodies, which
is crucial in the drug discovery
process. The innovation also
provides a more stable and
workable membrane model to
allow better understanding of
the mechanisms of diseases that
Dr Madhavan Nallani
nallanim@imre.a-star.edu.sg
Workshop on industrial coatings and packaging
More than 100 participants, mostly from industry, attended the workshop that introduced
IMRE’s various coatings and packaging-related R&D technologies.
Participants networking during the workshop on
industrial coatings and packaging.
The workshop on 24 May 11 was
held as part of the impending
launch of an industrial consortium
on coating and packaging
technologies led by IMRE. Some
of the technologies presented at
the workshop included
coatings for heat shielding
and sound attenuation,
hybrid polymer composites
coatings, silicone reinforced
UV curable hard coatings
and highly precise atomic
layer deposition for
coatings.
The planned Industrial
Coating and Packaging
(ICAP) consortium is a platform
for companies to reduce R&D risks
and investments in new coating or
packaging technologies by pooling
R&D resources in pre-competitive
projects. By doing so, companies can
affect human cells, such as cancer
and diabetes. The breakthrough
earned a spot as a finalist in
the Wall Street Journal’s Asian
Innovation Awards 2011.
With reference to Vesicular system
and uses there of (PCT/
SG2010/000159).
For more information about the
research, please contact
enhance or build new capabilities
as they embark in new product
development or to improve existing
products and processes.
For more information about the
Industrial Coating and Packaging
(ICAP) consortium, please contact
Mr Rick Ong
Industry Development Manager
ongr@imre.a-star.edu.sg
Highlight of
recent events
Tell us what you think of PERSPECTIVES!
Seminars and
workshops to
look out for!
CORPORATE NEWS
Smart biomaterials from IMRE
The new ‘smart’ biomaterials include a unique hydrogel
that has an on-off switch to precisely control its density
and a modular block copolymer that can be tailored to be
triggered by specific temperatures.
Researchers from
IMRE have
developed two new
‘smart’ biomaterials
that can be used for
unique drug delivery
and biomedical
applications.
One of the new
‘smart’ biomaterials
is the first ever
hydrogel with a
gelation process that can be started,
stopped and resumed at any time -
something not possible with any of
today’s hydrogels. The revolutionary
hydrogel gelation process creates
a single hydrogel that can vary in
thickness, shape and size. More
importantly, the gelation process,
or change in hydrogel density, can
be precisely controlled and turned
on and off by specific pH levels.
The other discovery is a novel
way to make temperaturesensitive
block copolymers that
allows researchers to create new
biomaterials by combining different
block copolymers, much like mixing
and matching LEGO toy building
blocks. The uniqueness of IMRE’s
block copolymers is this mix-andmatch
option that allows many new
Photograph illustration of hydrogel formation
controlled by pH.
What does this mean for you?
properties to be manifested through
different combinations of polymers.
For more information about
the research, please refer to:
‘Living’ Controlled in Situ
Gelling Systems: Thiol-Disulfide
Exchange Method toward Tailor-
Made Biodegradable Hydrogels
De-Cheng Wu, Xian Jun Loh, Yun-
Long Wu, Chee Leng Lay, and Ye Liu
J. AM. CHEM. SOC. 2010, 132,
15140–15143
Self-Assembly and Micellization
of a Dual Thermoresponsive
Supramolecular Pseudo-Block
Copolymer*
Zhong-Xing Zhang, Kerh Li Liu, and
Jun Li
Macromolecules, 2011, 44 (5), pp
1182–1193
*One of its top ten most read articles for the
first quarter of 2011.
IMRE scientists have developed a hydrogel
that could be loaded with different drugs
in one dosage for release at different
densities and at different pH levels, such
as what happens on sweaty versus nonsweaty
skin, or in the oral cavity versus
the stomach. A newly developed block
copolymer can also be triggered to change its nanostructure in two
stages at different temperatures so that different active contents such
as medicines can be released at those specific temperatures.
Dear Readers,
Since its first issue in April 1998, IMRE’s PERSPECTIVES newsletter has been reaching out to you, our readers, collaborators and stakeholders, both in academia and industry.
The newsletter has grown and matured through the years. As we seek to continually improve on the newsletter and its content, we would like to hear from you, our current
readers as well as potential subscribers, about what you think of the newsletter and what else you would like to see in it.
Please do help us to make the PERSPECTIVES better by answering 10 simple questions online at IMRE’s website at http://www.imre.a-star.edu.sg/newsletter.
Institute of Materials Research and Engineering (IMRE) • A*STAR • Singapore • Institute of Materials Research and Engineering (IMRE) • A*STAR • Singapore • Institute of Materials Research and Engineering (IMRE) • A*STAR • Singapore • Institute
Page 01

Publication highlights
Listed below are some noteworthy IMRE research
publications.
Page 02
RESEARCH
Record-breaking electroluminescence from bluelight
emitting materials
Achieving Highly Efficient Fluorescent Blue Organic Light-Emitting
Diodes Through Optimizing Molecular Structures and Device
Configuration; Adv. Funct. Mater. 2011, 21, 699–707; Chang-Gua Zhen,
Yan-Feng Dai, Wen-Jin Zeng, Zhun Ma, Zhi-Kuan Chen, John Kieffer
Abstract: Based
on the results of
first-principles
calculations of
the electronic
properties of blue
light-emitting
materials, the
molecular
structures of
oligofluorenes
were optimised
by incorporating
electronwithdrawing
groups into the molecules to balance
hole and electron injection and
transport for organic light-emitting
diodes (OLEDs). This resulted in a
remarkable improvement in the
maximum external quantum efficiency
(EQE) of the undoped device from
2.0% to 4.99%. Further optimisation
“…pure blue emission
with an extremely high
maximum EQE of 9.40%
was achieved...”
of the device configurations and
processing procedures led to a
very high maximum EQE of 7.40%
for the undoped sky-blue device.
Finally, by doping the emitter in a
suitable host material and at the
optimal concentration of 6%, pure
blue emission with an extremely
high maximum EQE of 9.40% was
achieved, which trumps the current
The new material was used to produce this deep blue
organic light emitting diode (OLED) that is driven at 6V.
theoretical 5% maximum limit. The
achievement allows manufacturers of
full colour OLED displays to use the new
materials to make devices that have
significantly longer lifetime, consume
less power and more importantly, can
emit pure, and brighter blue light to
give more life-like colours to OLED
displays. This could greatly enhance
the attractiveness of OLED displays in
the consumer market.
For more information about the
publication, please contact
Dr Chen Zhikuan
zk-chen@imre.a-star.edu.sg
New method allows greater variety of deposited metals on
semiconductor nanorods
World experts in IMRE for atomic
interconnection tool workshop
Experts from around the globe
gathered in IMRE for a workshop
on atomic scale interconnection
machines. The event was held as part
of the European Union’s €10 million
Atomic Scale and Single Molecule
Logic Gate Technologies, or AtMol
project in which IMRE is the only
non-EU partner. The project lays the
foundation for creating and testing a
molecule-sized processor chip.
The atomic scale interconnection
machines are used to physically
move atoms into place one-by-one
to construct atomic scale circuits at
cryogenic temperatures. The tools
are also able to interconnect the tiny
circuits of the device to the external
environment.
The machines are essentially miniature
high precision scanning tunnelling
microscopes (STMs) that can image a
surface with picometer precision and
manipulate one atom or molecule at
a time. The STMs are coupled to a
high-resolution electron microscope
that allows a researcher to position
interconnects to make an atomic
Light-Induced Selective Deposition of Metals on Gold-Tipped CdSe-Seeded CdS Nanorods; J. Am. Chem.
Soc. 2011, 133, 672–675; Xinheng Li, Jie Lian, Ming Lin, and Yinthai Chan
Abstract: A new approach for the
selective deposition of metals on Autipped
CdSe-seeded CdS nanorods
using UV excitation was developed.
This light-induced deposition
method allowed Pd to be selectively
deposited under mild conditions,
which produced a Pd/Au alloyed
tip while preserving the rest of the
semiconductor nanoarchitecture.
Before the success of this method,
the metals that could be deposited
on semiconductor nanorods were
limited because only mild chemicals
could be used. The chemicals needed
in conventional treatment had to be
mild so that it would not degrade
the semiconductor nanorod, which
would affect the performance and
photocatalytic properties of the
metal-semiconductor nanorods.
This research effectively expands
on the range of metals that can
be deposited on heterostructured
Metal-semiconductor matchstick-like
structure viewed under high-powered
transmission electron microscopy.
“This research
effectively expands on
the range of metals
that can be deposited
on heterostructured
semiconductor nanorods...”
semiconductor nanorods, opening
up new avenues for the hierarchical
Institute of
Materials Research
and Engineering
IMRE hosts workshop on the advanced tools needed to build a molecule-sized chip.
Participants of IMRE’s international workshop on atomic scale interconnection
machines.
buildup of structural complexity
and therefore multifunctionality
in nanoparticles. The researchers
are already looking at using the
new method to produce materials
that have ‘green’ photocatalytic
applications such as materials that
enhance water-splitting to produce
hydrogen more efficiently for fuel
cell; and materials that actively
degrade environmental pollutants
on exposed surfaces like buildings
and cars.
For more information about the
publication, please contact
Dr Chan Yin Thai
chanyt@imre.a-star.edu.sg
scale circuit. Speakers from Europe,
USA, Japan, Canada, Australia and
Singapore discussed advancements
in ultra-high vacuum (UHV) tools and
plans for the next generation tools.
“Because we are working at the scale
of the atom, our tools have to be
ultra high-precision and of extremely
high-calibre, just like IMRE’s UHV
interconnection machine, which is one
of the three in AtMol that can study the
performance of single molecule and
surface atom circuit logic gates”, said
the AtMol project leader, Prof Christian
Joachim of the French Centre National
de la Recherche Scientifique (CNRS)
and an A*STAR Visiting Investigator at
IMRE. “This workshop brings together
the world’s foremost experts to discuss
the latest in atomic interconnection
machine technology and how this can
quicken the pace towards a working
molecular chip.”
“The tools and the level of expertise
that IMRE is contributing to this project
show that the research in Singapore
is truly at the cutting edge of global
science”, said Prof Andy Hor, Executive
CORPORATE NEWS
How low can you go?
IMRE built the world’s first
controllable molecular gear.
The AtMol project is part of
research that is looking at new
ways to build miniaturised
devices and electronics. It is
estimated that conventional
methods for miniaturising
devices will reach their limit
in 10-15 years and cannot
be reduced further. This
method is a leading alternative
in the race to achieve
continued miniaturisation of
nanoelectronic devices. The
research team in IMRE is one
of the pioneers in atomic
scale technology, having built
the world’s first controllable
molecular gear and constructed
the smallest digital logic gate
using a single molecule. IMRE
also houses one of the few
R&D tools worldwide that is
powerful enough to study
single molecule logic gates and
surface atom circuit logic gates.
Director of IMRE. “IMRE is extremely
glad to host the event and be a part
of a truly momentous scientific effort.”
‘Machines that build and connect atomic
scale circuits’ infographics on page 3
New ambipolar polymer semiconductors for
flexible plastic electronic devices
A Low-Bandgap Diketopyrrolopyrrole-Benzothiadiazole-Based
Copolymer for High-Mobility Ambipolar Organic Thin-Film
Transistors; Adv. Mater. 2010, 22, 5409–5413; Prashant Sonar,
Samarendra P. Singh, Yuning Li, Mui Siang Soh and Ananth
Dodabalapur
Abstract: A new solution
processable, low band gap polymer
semiconductor comprised of donoracceptor
blocks was designed and
synthesised via Suzuki coupling.
The new ambipolar polymer
semiconductor has improved
intermolecular interactions due to
π-π stacking of donor and acceptor
blocks. The polymer exhibits
ambipolar charge transport which
“The balanced hole and
electron mobility values
are among the highest for
single component ambipolar
organic thin-film
semiconductors…”
RESEARCH
allows the transport of both
positive (holes) and negative
(electrons) charges. The hole
and electron mobilities are
0.35 cm 2 /V.s and 0.40 cm 2 /V.s,
respectively when used as the
active semiconductor in organic
thin-film transistor (OTFT) devices.
The balanced hole and electron
mobility values are among the
highest for single component
ambipolar organic thin-film
semiconductors that have been
reported so far. The new polymer
is simpler to manufacture, easy
to process and is suitable for
creating electronic circuits. This
polymer has the potential to be
(continued on page 4)
Institute of Materials Research and Engineering (IMRE) • A*STAR • Singapore • Institute of Materials Research and Engineering (IMRE) • A*STAR • Singapore • Institute of Materials Research and Engineering (IMRE) • A*STAR • Singapore • Institute

Institute of
Materials Research
and Engineering
CORPORATE NEWS
of Materials Research and Engineering (IMRE) • A*STAR • Singapore • Institute of Materials Research and Engineering (IMRE) • A*STAR • Singapore • Institute of Materials Research and Engineering (IMRE) • A*STAR • Singapore • Institute of Mater
Page 03

(continued from page 2)
Institute of
Materials Research
and Engineering
27 May 11
IMRE hosted a visit for students
of the Singapore International
Science Challenge (SISC) 2011,
a biannual international science
competition organised by the
National Junior College (NJC) to
provide opportunity for students
from different countries to interact
and showcase their research
projects. The students were introduced to IMRE’s research on functional
silk, water analyser technology and materials characterisation.
Institute of Materials Research and Engineering (IMRE) • A*STAR • Singapore • Institute of Materials Research and Engineering (IMRE) • A*STAR • Singapore • Institute of Materials Research and Engineering (IMRE) • A*STAR • Singapore • Institute
Page 04
Schematic of OFET device geometry and nano-fibrillar thin film morphology of ambipolar polymers.
deployed in ambipolar transistorbased
complementary circuits
in printed electronics. The
fabrication of complementary
circuits would also be simplified
using the solution-processable,
single-component ambipolar
thin-film semiconductor. The new
Dr Tan Yen Nee was awarded
the Best Presenter in the
Professional Category and Ms
Jasmine Yuen won a Distinction in the
Poster Presentation of the Biomedical
Engineering Society (Singapore)
(BES) 5th Scientific Meeting held at
Nanyang Technological University,
Singapore on 28 May 11. Yen Nee
National Chemistry Week
OUTREACH
IMRE was involved in a number of activities held in conjunction with the
week-long National Chemistry Week (28 May – 5 June 2011).
Dr Davy Cheong (foreground) conducting
a demonstration during the “Chemistry
Here, There and Everywhere” show.
Organised by the Singapore
National Institute of Chemistry,
the National Chemistry Week is a biannual
event that raises awareness
on the importance of chemistry
as a science and how it impacts
daily life. The 2011 festivities were
particularly meaningful as this year
is the United Nations-designated
material, which can be adapted to
high-volume roll-to-roll printing,
can speed up the development of
large area scale flexible and plastic
electronics devices.
For more information about the
publication, please contact
IMRE researchers win the Best Presentation (Professional Category) Award and a Distinction in
the poster presentation category at Biomedical Engineering Scientific Meeting 2011.
presented her research on the topic
of “Rapid Colorimetric Biosensors
Based on Non-crosslinking
Aggregation of Gold Nanoparticles”
while Jasmine’s poster was on the
“Capacitively coupled contactless
conductivity detection of inorganic
cations in rabbit blood serum,
human urine and sweat using
Students at the IMRE Workshop on
Chemistry of Materials.
International Year of Chemistry.
IMRE worked with the organisers
to help celebrate the event by
conducting a laboratory visit and a
public science demonstration.
Drs Karen Chong, Chua Yang
Choo and Davy Cheong from
IMRE performed a live science
show entitled, “Chemistry Here,
RESEARCH
Dr Prashant Sonar
sonarp@imre.a-star.edu.sg
AWARDS
AWARDS
microchip electrophoresis”. The
meeting showcased a wide range
of Singaporean biomedical R&D
activities from junior colleges,
polytechnics, universities as well
as from professional researchers in
areas such as bionanotechnology,
regenerative medicine, bioimaging,
sensors and biomechanics.
There and Everywhere” at the
launch of the National Chemistry
Week on 28 May 2011. The
show combined demonstrations
on chemistry science, slide shows,
videos to highlight the impact and
applications of chemistry in today’s
world.
IMRE also organised a halfday
Workshop on Chemistry of
Materials on 30 May 11 for students
that featured researchers from
IMRE and the National University
of Singapore as well as two junior
college attachment students who
spoke on their experiences working
in the IMRE laboratories. The
workshop ended with a laboratory
tour showcasing IMRE’s facilities
and research.
25 May 11
Prof Andy Hor, IMRE’s Executive
Director was invited to speak at
the annual Shell Singapore Youth
Science Festival Student Seminar.
More than 100 students and
teachers from secondary schools
and junior colleges attended the
talk where Prof Hor spoke about
Prof Andy Hor, Executive Director of
IMRE, presenting at the Shell Singapore
chemistry and its applications in Youth Science Festival.
daily life through his talk entitled, “Chemistry is in Our Life”.
Past issues of our newsletters are available on our website at
www.imre.a-star.edu.sg
For general enquiries please write in to
enquiry@imre.a-star.edu.sg
OUTREACH
Shell Singapore Youth Science Festival
Presentation
Visit by Singapore International Science
Challenge (SISC)
Participants of the SISC visiting an IMRE
lab.
NUS Chemistry Camp visit at IMRE
03 June 11
Some 35 junior college participants
of the NUS Chemistry Camp were
at IMRE to experience what a
research environment was like.
With a focus on chemistry the
group was introduced to IMRE’s
characterisation facilities and R&D
on composites, biosensors and
quantum dots.
IMRE hosts students from NUS Chemistry
Camp.
UPCOMING EVENTS
Diary of upcoming events @
IMRE
20 Jul 11
Chemistry – People & Opportunities in Singapore 2011
Inaugural Royal Society of Chemistry Singapore Section
symposium
IMRE, Singapore
22 – 24 Jul 11
X-periment Exhibition
Suntec City, Singapore
09 – 11 Jan 12
Molecular Materials Meeting (M3) @ Singapore
Biopolis, Singapore
To find out more about IMRE’s seminars and events, please
visit www.imre.a-star.edu.sg/eventsall.php