Tag Archives: nanomaterials

Drops from thin air

The University of Sydney Nano Institute team

University science is behind some of the most profound innovations and breakthroughs in water research, from the development of cutting-edge techniques to maximise irrigation, to the creation of innovative new materials that can literally capture water from the air.

At the University of Sydney, the Advanced Capture of Water from the Atmosphere (ACWA) project applies nanoscale materials science to mimic the remarkable adaptation of desert beetles in Namibia, a region where just 1.4cm of rain falls each year. The beetle collects water vapour from the atmosphere, turning it into liquid via the intricate shapes of tiny bumps on its exoskeleton.

Biomimicry — learning from, and mimicking, clever strategies found in nature to solve human design challenges — is an important component of the work of the University of Sydney Nano Institute, co-led by chemist Professor Chiara Neto and physicist Professor Martijn de Sterke. Innovations from the research include a nanotextured surface which can repel bacteria, algae and other marine life from ships’ hulls, inspired by a lotus leaf; a nanoscale slippery surface, inspired by the pitcher plant, that can be used for microfluidic channels in bioengineering; and a stain-resistant paint base.

The Institute has attracted top-level researchers from chemistry, physics, materials science and bioengineering from across the university.

“We began with the idea of capturing water from the atmosphere by optimising the surface chemistry of a material so it would enable the formation of droplets out of humid air,” says Neto.

“We are now developing new devices that capture water from the atmosphere through condensation, using no external source of energy, by designing surfaces that spontaneously cool when exposed to the air,” she says.

Related: Software saves rainwater

The team has made two key breakthroughs. First, they have perfected the surface science of nanoscale ‘bumps’ shaped in a way to harvest a very thin film of water vapour, similar to the Namibian desert beetle.

Their second breakthrough is the development of an entirely new surface that is naturally chilled and causes water to condense into droplets. Wherever the atmosphere is above 30% humidity, this surface will automatically collect water vapour from the air.

The ACWA project is well on the way towards its ambitious goal to create materials that capture sufficient water from the atmosphere to alleviate the effect of drought by providing water for humans, animals and plants.

Patents are underway for exciting applications for the technology, including watering devices to use within greenhouses; a portable self-filling water bottle for bushwalkers and emergency crews; and small water stations to sustain wildlife in remote areas

Fran Molloy

This article appears in Australian University Science issue 2.

biophotonics

Biophotonics pioneer

Featured image above: biophotonics Professor Dayong Jin. Credit Vanessa Valenzuela Davie

Professor Dayong Jin envisions a future where portable diagnostic devices will be as ubiquitous as smartphones, where scientists can peer inside individual cells, and where diseases can be detected before they infect our bodies.

A pioneer in the emerging field of nanoscale biophotonics at the University of Technology Sydney (UTS), it’s a future Jin is working hard to create.

“The nanoscale is really the fundamental level on which biological molecules operate,” he says. “It’s the scale of the original disease.”

Jin engineers functional nanoparticles – invisible to the naked eye – which harness light to probe our cells, detect diseases and deliver drugs in perfectly measured doses.

Transforming the biomedical industry with biophotonics

Jin was recently named the Director of a new A$3.7 million Australian Research Council Industrial Transformation Hub. The hub’s objective is to develop portable diagnostic devices with vastly improved detection capabilities.

These easy-to-use devices, which incorporate nanomaterials and photonic technologies developed by Jin and his colleagues from UTS and the University of South Australia, can analyse incredibly small samples of substances including breath, saliva, urine and blood, to find markers of disease.

Jin says these point-of-care technologies will ease the burden on hospitals and align with the demands of consumers: real-time health monitoring, and faster treatment options.

“In the near future, prostate cancer patients who have gone into remission will have a handheld device at home to analyse their urine samples,” he says. “It will be able to tell them whether their cancer is recurring.”

The hub is also working with industry partners to develop an improved roadside breath-testing device for police forces to detect traces of illicit drugs.

Over its five-year lifespan, Jin expects the hub to generate a number of new portable diagnostic devices, which can be tailored to specific applications to detect everything from cancers to infectious diseases and environmental pollutants.

Super Dots diagnose diseases inside the body

Jin is also helping improve disease diagnosis from inside the body itself.

Cancers and infectious disease outbreaks all originate from a single cell, he says.

“The current challenge is that we don’t have a method to find this very rare cell from the earliest stage.”

Jin was part of an Australian research team that developed a technology known as Super Dots, which won a prestigious Eureka Prize in 2015. These nanoparticles can find a needle in a haystack, detecting individual diseased cells from a population of millions.

The particles are made from a nanocrystal material that can absorb invisible infrared light and emit higher energy, visible light, says Jin.

Once the nanoparticle has found the target cell inside the body, or a blood sample, it can be stimulated by researchers with a harmless, skin-penetrating infrared light.

The dot then emits a visible flash, which causes the diseased cell to light up.

“It’s like you have the diseased cell glowing in the darkness,” says Jin. “This allows you to achieve the ultimate detection sensitivity.”

Beyond medicine, Super Dots can be encoded with “secret signatures” and used for the anti-counterfeiting of passports, banknotes and drug labels, says Jin.

There are also applications for more efficient solar cells and 3D display screens.

Biophotonics pioneer featured video above: Superdots, WINNER 2015 Eureka Prize for Excellence in Interdisciplinary Scientific Research.Credit: Australian Museum.

Breaching the blood-brain barrier

Jin is hopeful that another class of his nanoparticles will serve as a versatile drug delivery vehicle, capable of breaching the protective blood-brain barrier.

Delivering drugs to individual neurons in the brain is a “holy grail problem” in neurological research, says Jin.

“There are many drugs already developed to treat Alzheimer’s and Parkinson’s quite effectively outside the body,” he says. “But the blood-brain barrier prevents more than 99 per cent of drugs from accessing the brain from the blood circulation system.”

Jin and his colleagues have created a library of 800 types of nanoscale drug carriers with specific shapes, sizes and surface functionality. Importantly, they have developed a process to replicate these carriers exactly, according to any design.

“We’ve solved the problem in terms of developing the material,” he says.

“If the tailored drug carrier can tell the blood-brain barrier that the carriers are the friend and not the enemy… we can open a gate into the brain.”

Super-resolution microscopy breakthrough

biophotonics
Super resolution image of the single cell nuclear membrane pores. Credit: Professor Dayong Jin.

Jin’s research has led to a recent breakthrough in the field of microscopy.

With colleagues at Georgia Institute of Technology in the US and Peking University in China, Jin has developed a simple but highly effective way to see individual cells in 3D – overcoming a major barrier. Instead of growing cells on transparent glass slides, the team grew their cells on specialised mirrors. As reflected light passed through the cell while being viewed under a super-resolution microscope, researchers could see new structures in exquisite detail.

“This simple technology is allowing us to see the details of cells that have never been seen before,” says Jin. “We can see the tiny little hole on the cell nucleus’ membrane – that hole is the entrance and exit for single molecules.

“When the cell wants to express a signal, or send a message outside the cell, this is the gateway – and we now have the tool to see what that looks like.”

By understanding how cells behave, communicate and how diseases arise inside them, researchers can develop more effective treatments.

Jin and Professor Peng Xi from Peking University hold a patent for their invention, and Jin says they are currently exploring opportunities to commercialise the technology with leading imaging companies such as Olympus and German firm Leica.

Multiculturalism trumps geography for Australia

It was love that brought Jin to Australia from his home in northeastern China, near the border with inner Mongolia. His future wife, Lisa Li, came to Sydney to study accounting in 2002, and he followed.

Jin ended up at Macquarie University in the laboratory of Dr Jim Piper, a renowned expert in lasers, optics and photonics. Under his guidance, Jin developed a system to detect trace amounts of pathogens in water.

Jin says the postgraduate scholarship in Australia was more comprehensive and generous than what was offered to his Chinese peers who chose to study in the US.

Jin says he and his family had planned on returning to China or finding a postdoctoral position in the US after his PhD, but ultimately decided to stay in Australia.

He says the decision has been good for his career: “Geographically, Australia looks like it’s isolated,” he says. “But we are actually well connected.

“The Australian research community is very multicultural, and these ‘soft connections’ have created a lot of opportunities for my research collaborations.”

Jin says multidisciplinary knowledge and collaboration is vital to realising the healthcare future he envisions – and going even further beyond.

In addition to his many breakthroughs in biophotonics, one of the prospects Jin is most excited about is that of truly personalised medicines.

At present, people with the same diseases are all treated with the same drugs, which might be totally ineffective for a proportion of the population, says Jin.

“But future medicines will have a tool to decode the unique molecular signature of a patient,” he says.

It means when two people have the same disease, they could be treated remarkably differently – with dramatically improved outcomes.

This is where we’re heading, he says.

– Myles Gough
This article on the biophotonics pioneer, Professor Dayong Jin, was first published by Australia Unlimited on 9 August 2016. Read the original article here.
gemstones-nanomaterials

Tiny gemstones advance nanoscale imaging

Featured image above: Nanomaterials composed of tiny diamonds and rubies can be used to light up and image a long chain of proteins. Credit: Carlo Bradac

A research team at the ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP) – led by Dr Philipp Reineck from RMIT University’s School of Science – tested the ruby and diamond particles, more than a thousand times smaller than the diameter of a hair, alongside other nanoparticles for use in biological imaging, and found that they have a higher degree of stability, critical to achieving imaging success.

“Fluorescing nanoparticles can be used as ‘tiny lamps’ that when placed in the body, are able to light up cells and their internal processes.”

“We shine light at the biological sample of interest in a very controlled way and the nanomaterials send light back, helping us to see very specifically what is happening, right down to a molecule and protein level.”

“This is the area we’re focused on, exploring how the ‘very small’ can help us in answering some of the very big questions in biology.”

In the study published in the journal Advanced Optical Materials, the team compared seven types of fluorescent nanomaterials – organic dyes, semiconductor quantum dots, fluorescent beads, carbon dots and gold nanoclusters, as well as the nano sized diamonds and rubies.

Characteristics tested for included levels of fluorescence brightness and photostability (resistance to change under the influence of light), as well as how efficiently these new materials can be imaged using standard microscopes used in biology.

“Nanomaterials have widely differing characteristics and we need to determine which materials will work best in which imaging application,” Reineck said.

“What our study clearly shows is that nanodiamonds and nanorubies are excellent materials for long-term biological imaging.

“These two materials provide acceptable levels of brightness and the best photostability by far, when compared to the other materials that were tested.”

In other study findings, Reineck noted clear trade-offs in many of the nanomaterials examined.

“We found that ideal levels of photostability generally mean a sacrifice in brightness and vice versa,” he said.

“For example, during testing, the organic dyes and carbon dots were much brighter than the rubies and the diamonds – but photobleaching (or fading) was a major issue, impacting their practical imaging use.”

Reineck’s next step will be to work closely with biologists and medical researchers within the CNBP to develop selected nanomaterials so that they can be used with the needed precision and reliability to light-up real-world biological environments.

Future application of the materials will relate to fertility, chronic pain and heart disease research, key focus areas for the CNBP.

“The real treasure isn’t the rubies or the diamonds,” concluded Reineck.

“It will be the way in which we use these materials to shed new light on the incredibly complex processes taking place in the living body, helping us understand a whole host of matters relating to health, wellbeing and disease.”

The Centre for Nanoscale BioPhotonics (CNBP) is an Australian Research Council Centre of Excellence, with research focussed nodes at the University of Adelaide, Macquarie University and RMIT University.

A $40 million initiative, the CNBP is focused on developing new light-based imaging and sensing tools, that can measure the inner workings of cells, in the living body.

– Petra van Nieuwenhoven

This article was first published by RMIT University on 20 July 2016. Read the original article here.