chemistry

Alex Donald pic

A Sydney scientist has created the world’s smallest metallic wire, which is 100,000 times shorter than the width of a hair.

Dr Alex Donald, of the University of New South Wales, manipulated five silver atoms into a zigzag-shaped metal wire, overcoming previous difficulties of creating anything smaller than one-billionth of a metre.

“Scientists can already create metallic wires that are measured in nanometres, or one-billionth of a metre, which are many times larger than this wire. A key challenge in going smaller is that it becomes increasingly difficult to isolate and determine the shapes of such small particles,” says Alex, an ARC Discovery Early Career Researcher Award fellow and chemistry lecturer at the University of New South Wales.

Alex used an advanced instrument at the University of Melbourne to first manipulate the five atoms into a bowtie shape and then into a zigzag-shaped wire. He found that the addition or removal of a chemical allowed him to switch between shapes.

“We do not yet know what we can do with this wire, if anything, but these results demonstrate that an impressively small metal cluster can be entirely isolated and moulded into a relatively predicable shape,” he says.

These atom clusters have unique properties, including high-surface areas, which may ultimately make them useful as sensitive chemical sensors. For example, if one ounce of silver was converted into five-atom clusters, the total surface area of the clusters would be equivalent to 10 times the area of Australia.

NSW State Finalist: Alex Donald, University of New South Wales

Aliaa-Shallan-front

The dream of affordable personalised medicine is one step closer to reality as a Tasmanian scientist shrinks a drug-testing laboratory to a size of a hand.

Aliaa Shallan, a PhD student at the University of Tasmania’s school of chemistry, is developing a portable unit that can analyse the drug quinine, using a single drop of blood and costing only a few dollars per test.

“It is devices like this that will make the dream of personalised medicine affordable and dramatically change the quality of life of billions of people around the world,” Aliaa says.

“The challenge was to extract the drug without blood cells and proteins, for which I created nanofilters using controlled lightning; an electric field applied across a thin part of the device. The cost is the lowest among existing nanofabrication techniques,” Aliaa says.

Billions of people take prescription drugs every day but the optimum dose for each person can vary greatly. Personalised medicine accommodates these differences by tailoring the dose according to the drug level in the blood.

Aliaa says creating simple devices that can be used at home is the answer to measuring individual needs without compromising lifestyle. “One example is glucose meters but similar devices for other drugs like antiepileptics and antidepressants are not available,” she says.

The next step in her research will be to apply her method to other approved drugs and to engineer the device for commercialisation.

Tasmania State Finalist: Aliaa Shallan, University of Tasmania

http://freshscience.org.au/2013/portablelab

Soil has the answer to burning climate questions


Decreasing the frequency of wild fires in northern Australia would lead to an increase in the amount of carbon stored in the soil, significantly lowering greenhouse gas emissions, according to CSIRO ecologist, Dr Anna Richards. [click to continue…]

…by putting the squeeze on mining waste

You may not be able to squeeze blood out of a stone but, by applying the right amount of ultrasound during processing, Jianhua (Jason) Du and colleagues from the Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE) have been able to squeeze a considerable amount of fresh water from mining waste. [click to continue…]

Patented South Australian technology

South Australian researchers have invented and patented a new technology for delivering cosmetics and drugs to the skin.They are using nanoparticles of silica (essentially sand) to create longer lasting cosmetics and creams that control the delivery of drugs through the skin.

They already have a family of international patents on their technology, and are now actively looking for commercial partners to get their invention out of the lab and on to your skin.

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A young Monash University chemist and her colleagues have successfully strengthened insulin’s chemical structure without affecting its activity. Their new insulin won’t require refrigeration.

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p8070118‘Fool’s gold’ has tricked many amateur gold miners, but Queensland researchers have discovered it can reveal much about the early evolution of life on Earth.

Three billion years ago the Earth couldn’t support life as we know it – the atmosphere was deadly to oxygen-breathing plants and animals.
But two and half billion years ago life changed the Earth’s atmosphere creating the oxygen-rich air we rely on today. [click to continue…]

An international team of astronomers has discovered the oldest and most distant carbon in the Universe, but there’s not enough of it to support standard theories of how the Universe lit up, a member from Swinburne University of Technology has calculated.

In the early Universe a dark pervasive fog of neutral hydrogen gas lurked everywhere. Astronomers think that this fog cleared when the first stars formed and emitted light.

There is a close connection between the amount of light and carbon produced in stars. But adding up all the 13-billion-year-old carbon detected, Dr Emma Ryan-Weber and her collaborators came to the conclusion the amount of carbon, and therefore the number of massive stars, was insufficient to lift the fog. [click to continue…]

Doctoral student Jacqueline Burgess from La Trobe University has identified odour molecules associated with the small brown stomach worm.

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Australian orchids are engaged in an arms race, using sensory overload to seduce male insects.

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A research team in Sydney has created molecules that mimic those in plants which harvest light and power life on Earth.  

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The cleaning power of sound waves on the back of a truck

A young researcher in Sydney is cleaning up contaminated soil by blasting it with ultrasound.

Andrea Sosa Pintos from CSIRO Industrial Physics has shown that toxic and carcinogenic pollutants, such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), can be decomposed quickly, easily and cheaply using a portable treatment unit.

 ”Chemical analysis of the soil and water after we’ve treated it confirms that more than 90 per cent of pollutants have been destroyed,” she says.

Present soil remediation techniques such as landfill disposal, incineration and bioremediation, have many limitations. “None of these provides a complete or cost-effective solution. And some of them can be time-consuming.” says Sosa Pintos.
“Our process is very simple. We generate high-power ultrasound waves in a slurry of the contaminated soil in water,” Sosa Pintos explains.

The soil and water are mixed and the slurry is pumped through a treatment unit where it is exposed to the ultrasonic waves. The whole process only takes a matter of minutes, as opposed to hours and days, or even months using other techniques.

 ”Ultrasonic waves travelling through the mixture create micro-bubbles. When these bubbles burst on the surface of the soil particles, they release intense shock waves which can generate temperatures of up to 5000 degrees Celsius. Any chemical contaminants on the surface of the soil particles bear the brunt of these bursts of energy and are blown apart,” she says.

Importantly, the surrounding liquid stays cool, eliminating the possibility that the remnants of the toxic compounds can recombine to form dangerous by-products, as sometimes happens using other technologies. Dioxins are formed during incineration, for instance.

The pilot plant Sosa Pintos and her colleagues have developed can already process about a tonne of soil a day. For a commercial scale system a more efficient feeder unit including a higher capacity pump would be required.

Sosa Pintos says. “If the right engineering company were interested, within a couple of years we could develop a commercial treatment unit able to be hauled to contaminated sites on the back of a truck.”

The combination of high destruction rates, very low energy costs, and the convenience of on-site treatment, makes high-power ultrasound a promising option for soil remediation. 

Andrea Sosa Pintos is one of 16 Fresh Scientists who are presenting their research to school students and the general public for the first time thanks to Fresh Science, a national program hosted by the Melbourne Museum and sponsored by the Federal and Victorian governments, New Scientist, The Australian and Quantum Communications Victoria.  One of the Fresh Scientists will win a trip to the UK courtesy of the British Council to present his or her work to the Royal Institution.

Research by a Perth forensic scientist is helping to
stem the flood of forgeries entering the international
antiques market.

A Perth forensic scientist is employing lasers to help trace pottery back to
the kiln site of its production, thus exposing ceramic forgeries, a multi-million
dollar criminal business.

Emma Bartle from the Centre for Forensic Science at the University of Western Australia has developed a scientific method to authenticate porcelain, based on a technique known as elemental fingerprinting originally used to establish where gold came from. It employs lasers to vaporise a minute amount of material, which can then be analysed for the elements it contains, and how much of each is present. The process causes no visual damage to the ceramics.

“Over the past decade a multi-million dollar industry has grown up in South-East Asia, Cambodia and Laos to forge Chinese Ming and Japanese Imari porcelain,” Bartle says. “These modern fakes are so detailed and sophisticated that gone are the days whereby trained experts can authenticate pieces using visual examination alone.

“By analysing the porcelains’ chemical composition we can establish the geographical origins of an artefact and trace it back to the kiln site of its production in China or Japan. Each site has a different combination of trace elements, such as strontium and lanthanum, which is unique.”

The accepted conventional method of authentication at present uses emitted radiation to estimate the age of the porcelain; the idea being the older the object the less likely it is to be a fake. However, the process causes visible damage to the ceramics, decreasing both their cultural and monetary value. “Even worse, forgers have now caught up with the science and are artificially aging their imitations”, Emma remarks.

Elemental fingerprinting, pioneered by Prof John Watling for establishing the provenance of gold, is now routinely used in forensic applications. However, its adaptation and application to ceramics is new.

This unique research has sparked both local and international interest. Already museums, auction houses and private collectors have come forward to loan items from their collections for analysis. “We are working in collaboration with The Percival David Foundation of Chinese Art (London), Bonhams Auction House (London) and the Kyushu Ceramics Museum (Japan).”

“We have also analysed some of the ceramic artefacts recovered from Dutch shipwrecks along the Western Australian coastline, which were kindly loaned by the Western Australian Maritime Museum. Private collectors from the US and UK have also sent porcelain shards from their own collections for us to investigate,” says Emma.

Emma Bartle is one of 16 Fresh Scientists who are presenting their research to school students and the general public for the first time thanks to Fresh Science, a national program hosted by the Melbourne Museum and sponsored by the Federal and Victorian governments, New Scientist, The Australian and Quantum Communications Victoria.  One of the Fresh Scientists will win a trip to the UK courtesy of the British Council to present his or her work to the Royal Institution.

Salads, shampoos and mining to benefit from theoretical
research into droplets

How much effort does it take to understand the behaviour of oil droplets?
A multi-disciplinary team of six researchers from the University of Melbourne
has spent the best part of two years, and used $300,000 of equipment to crack
the problem.

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A new system for directing radiation to target cells has been developed in Melbourne. The new targeting system has the potential to specifically destroy cancer cells with minimal damage to healthy tissues.

The new targeting concept, for which an international patent is pending, uses a special class of radioactive atoms for which the radiation damage is confined to the molecules immediately adjacent to the radioactive atom.

The cell-killing effect is maximised by directing the radiation to the genetic material (DNA) of the target cell, with little effect on neighbouring cells.

“We expect that our targeting system will be particularly useful for small clusters of cancer cells, such as those that spread throughout the body when a cancer becomes more advanced,” says Dr Tom Karagiannis, research officer with the Peter MacCallum Cancer Centre where the system was devised.

Conventional cancer therapies such as surgery, radiotherapy and chemotherapy have resulted in a steady decline in cancer mortality rates over the years.  Only chemotherapy has the potential to be effective when the cancer has spread throughout the body, but often it is not effective.

Latest figures from the World Health Organization show that about 50 percent of cancer patients still die in developed countries and about 80 percent die in developing countries.

A unique feature of the cancer targeting system is the highly focussed damage caused by the radioactive isotopes used – most of the radiation damage is within a distance of only a few millionths of a millimetre.  This means they can kill cancer cells without causing significant damage to normal cells.

The new technology combines knowledge from a wide range of scientific disciplines, including radiation biology, chemistry and immunology, Dr Karagiannis says.  The key ingredient is a complex composite drug, made by attaching the radioactive atom to a DNA-binding molecule, which in turn is linked to a cancer-targeting protein such as an antibody.

“Our radiolabelled DNA-binding drug alone provided a very efficient ‘molecular bomb’ for destroying cells,” says Dr Karagiannis. “But it could not discriminate between cancer cells and healthy cells.”

To make a ‘smarter’ drug, researchers took advantage of the fact that many cancer cells express high levels of certain proteins on their cell surface. Antibodies that bind specifically to these surface proteins were used as vehicles to target the lethal damage to cancer cells.

“Our strategy builds on the growing interest in antibodies as cancer therapeutics,” says Associate Professor Roger Martin, Tom’s supervisor who has been working on the project concept for the past three decades.

“There are a currently only a handful of such anticancer-antibodies that have been approved for therapy and many others that are in clinical trials.”

Proof-of-principle studies with the new targeting system have yielded very promising results with cell cultures, but a commercial partner is required for further development.

Tom is one of 13 Fresh Scientists who are presenting their research to the public for the first time thanks to Fresh Science, a national program sponsored by the Federal and Victorian Governments. One of the Fresh Scientists will win a trip to the UK courtesy of the British Council to present his or her work to the Royal Institution.

Billion year old bacteria in NT rocks and bugs from outer space

Researchers from the CSIRO, Sydney University and Colorado State University have developed a means of detecting signs of ancient microbes which may have lived on Earth or come from outer space.

The group already has picked up signs of bacteria more than a billion years old inside rocks from the Northern Territory.

The technique centres around analysing tiny oil droplets-sealed inside rocks as they formed-for traces of chemical compounds known only to be produced by particular types of organisms. The results provide unequivocal evidence of their presence.

“Oil forms from decayed organisms, and therefore contains fatty tracers or biomarkers for the organism from which they came-like the footprint of a dinosaur, but at a molecular level,” says Herbert Volk from CSIRO Petroleum, a member of the research team.

“It’s important that we understand these early organisms, as they were the building blocks for the evolution of the more complex life forms which play an important part in today’s ecosystems.”

The team has managed to extract such biomarkers from oil droplets sealed in Precambrian rocks from the Northern Territory for more than a billion years.

The chemical analysis of the oil indicates that it is derived from single-celled cyanobacteria, the aquatic and photosynthetic bacteria responsible for increasing oxygen levels in the atmosphere. There is also evidence of the presence of more complex strains of life.

“Microscopic evidence of fossilised microbes is very rare in rocks of this age, and if present are often fiercely debated,” Volk says. “Biomarkers have been extracted from rocks of similar age before, but these were not from oil droplets sealed in crystals, so they may have been contaminated by more recent life forms. The new results are free of such doubt.

“And should oil inclusions be found in extraterrestrial rocks such as meteorites or Martian rocks, the molecular signature would be perfectly protected from traces of terrestrial life that could otherwise compromise the information.”

Herbert is one of 13 Fresh Scientists presenting their research to the public for the first time thanks to Fresh Science, a national program hosted by the State Library of Victoria. One of the Fresh Scientists will win a trip to the UK courtesy of the British Council to present his or her work to the Royal Institution.

To view larger image, click on image:  
Remote arid landscape near the drill site in the Roper Superbasin in the Northern Territory, near the Gulf of Carpentaria.
Photo: Dr David Rawlings
The Roper Superbasin is one of the oldest basins known to contain petroleum which is where the researchers look for life.
 This is a thin slice of rock viewed through a microscope with UV light. The oil inclusions are seen fluorescing in bright blue. What the researchers look for are biomarkers of life. Some of the chemical structures they look for are hopanes, derived mainly from hopanols which are fatty alcohols in the cell walls of bacteria.
This is the chemical structure of a hopane molecule.
Herbert Volk (right) and colleague Simon George (left), analysing the oil droplets using a mass spectrometer.