Ultra-fast Data Processing At Nanoscale

Advancement in nanoelectronics, which is the use of nanotechnology in electronic components, has been fueled by the ever-increasing need to shrink the size of electronic devices like nanocomputers in a bid to produce smaller, faster and smarter gadgets such as computers, memory storage devices, displays and medical diagnostic tools.

While most advanced electronic devices are powered by photonics – which involves the use of photons to transmit informationphotonic elements are usually large in size and this greatly limits their use in many advanced nanoelectronics systems. Plasmons, which are waves of electrons that move along the surface of a metal after it is struck by photons, holds great promise for disruptive technologies in nanoelectronics. They are comparable to photons in terms of speed (they also travel with the speed of light), and they are much smaller. This unique property of plasmons makes them ideal for integration with nanoelectronics. However, earlier attempts to harness plasmons as information carriers had little success.

Addressing this technological gap, a research team from the National University of Singapore (NUS) has recently invented a novel “converter” that can harness the speed and small size of plasmons for high frequency data processing and transmission in nanoelectronics.

This innovative transducer can directly convert electrical signals into plasmonic signals, and vice versa, in a single step. By bridging plasmonics and nanoscale electronics, we can potentially make chips run faster and reduce power losses. Our plasmonic-electronic transducer is about 10,000 times smaller than optical elements. We believe it can be readily integrated into existing technologies and can potentially be used in a wide range of applications in the future,” explained Associate Professor Christian Nijhuis from the Department of Chemistry at the NUS Faculty of Science, who is the leader of the research team behind this breakthrough.

This novel discovery was first reported in the journal Nature Photonics.

Source: http://news.nus.edu.sg/

Liver Cancer: NanoDiamonds Eliminate Resistant Stem Cells

A study led by the National University of Singapore (NUS) found that attaching chemotherapy drug Epirubicin to nanodiamonds effectively eliminates chemoresistant cancer stem cells. The findings were first published online in ACS Nano, the official journal of the American Chemical Society.
liver cancer

The research team, led by Assistant Professor Edward Chow, Junior Principal Investigator at the Cancer Science Institute of Singapore (CSI Singapore) at NUS, demonstrated the use of nanotechnology to repurpose existing chemotherapy drugs as effective agents against chemoresistant cancer stem cells. Chemoresistance, which is the ability of cancer cells to escape chemotherapy treatment, is a primary cause of treatment failure in cancer. Cancer stem cells, a type of cancer cell which initiates the formation of tumours, are commonly found to be more resistant to chemotherapy than the rest of the bulk tumour, which can lead to cancer recurrence following chemotherapy treatment. As such, there is intense interest in developing new drugs or treatment strategies that overcome chemoresistance, particularly in cancer stem cells.

In this study, widely-used chemotherapy drug Epirubicin was attached to nanodiamonds, carbon structures with a diameter of about five nanometres, to develop a nanodiamond-Epirubicin drug delivery complex (EPND). The researchers found that while both standard Epirubicin as well as EPND were capable of killing normal cancer cells, only EPND was capable of killing chemoresistant cancer stem cells and preventing secondary tumour formation in xenograft models of liver cancer.

Source: http://news.nus.edu.sg/

Robot Lifting Loads 500 Times Its Own Weight

Engineering team from the National University of Singapore (NUS) led by Dr Arian Koh has achieved a world record. They have designed an artificial muscle which could carry a weight 80 times its own while extending to five times its original length. The team’s invention will pave the way for the constructing of life-like robots with superhuman strength and ability.
Artificial muscles have been known to extend to only three times its original length when similarly stressed. The muscle’s degree of extensibility is a significant factor contributing to the muscle’s efficiency as it means that it could perform a wider range of operations while carrying heavy loads. Robots, no matter how intelligent, are restricted by their muscles which are able to lift loads only half its own weight – about equivalent to an average human’s strength (though some humans could lift loads up to three times their weight).
Dr Koh and his team used polymers which could be stretched over 10 times their original length. Translated scientifically, this means that these muscles have a strain displacement of 1,000 per cent. A good understanding of the fundamentals was largely the cause of their success, Dr Koh added.

We put theory to good use. Last year, we calculated theoretically that polymer muscles driven by electrical impulse could potentially have a strain displacement of 1,000 per cent, lifting a load of up to 500 times its own weight. So I asked my students to strive towards this Holy Grail, no matter how impossible it sounded,” he said.
Source: http://www.eng.nus.edu.sg/

Non-Invasive Treatment For Deep Cancer

PhotoDynamic therapy (PDT) as a non-invasive treatment of cancer is limited by the penetration depth of visible light needed for its activation. A Bioengineering team from the National University of Singapore – NUS – led by Associate Professor Zhang Yong has invented a novel method which will pave the way for PDT to treat deep-seated cancer as well. The researchers also revealed how they have been able to control gene expression – the release of certain proteins in our body – using their nanoparticles which could convert NIR (Near Infrared) light to UV light (visible light needed for effective activation).
NIR is a safe light as opposed to UV light, which could cause damage to cells. NIR can also penetrate deeper into tissues to target tumours.

Near Infrared Light -NIR-, besides being non-toxic, is able to penetrate deeper into our tissues. When NIR reaches the desired places in the body of the patient, the nanoparticles which we have invented, are able to convert the NIR back to UV light (upconversion) to effectively activate the genes in the way desired – by controlling the amount of proteins expressed each time, when this should take place, as well as how long it should take place” explains Prof Zhang.

Source: http://www.eng.nus.edu.sg/ero/announcement/web-zhangyong0912.pdf