Nanoparticles deliver successful cancer cure

Nanoparticles have been able to disable cancerous cells in living human bodies for the first time. The results are perfect so far, killing tumors with no side effects whatsoever. The Caltech researchers created the particles from two polymers plus a protein that binds to receptors on the surface of cancer cells and pieces of RNA called small-interfering RNA, or siRNA, designed to stop the RRM2 gene from being translated into protein. The siRNA works by sticking to the messenger RNA (mRNA) that carries the gene's code to the cell's protein-making machinery and ensuring that enzymes cut the mRNA at a specific spot. When the components are mixed together in water, they assemble into particles about 70 nanometres in diameter. The researchers can then administer the nanoparticles into the bloodstream of patients.


"Once inside the cell, the nanoparticles fall apart, releasing the siRNA. The other parts of the nanoparticle are so small, they pass out of the body in urine. "It sneaks in, evades the immune system, delivers the siRNA, and the disassembled components exit out," Davis says."



See Nature.

Nanolaser breakthrough crucial for optical computer miniaturisation

A new nanolaser device, called a "spaser," has been developed and is the first of its kind to emit visible light. It represents a critical component for possible future technologies based on "nanophotonic" circuitry.



The spasers contain a gold core surrounded by a silica shell filled with OG-488 green dye in spheres totalling 44nm in diameter. When a light was shone on the spheres, plasmons generated by the gold core were amplified by the dye. The plasmons were then converted to photons of visible light, which was emitted as a laser. The "spaser-based nanolasers" research is detailed in a paper appearing online in the journal Nature that reports on work conducted by researchers at Purdue, Norfolk State University and Cornell University.

See Purdue University.

Spin-torque nanomagnet switching breaks speed limits

Dynamic Static Random Access Memory (DRAM) and Static Random Access Memory (SRAM) require constant power in order to retain memory. Using a magnetic memory chip known as Magnetic Random Access Memory (MRAM), information can be stored in the form of magnetization. The newest generation of MRAM employs the spin-torque effect for programming the magnetic bits. By using a current pulse, the spin-torque can be controlled and the memory state of the cell can be programmed. An experiment performed at the Physikalisch-Technische Bundesanstalt (PTB) in Germany has uncovered that a spin-torque switching of a nanomagnet is as fast as what is permitted according to the fundamental laws of physics’ limit.

This method of switching, also named ballistic switching, could allow for increased speeds in future non-volatile magnetic memories.

See thefutureofthings.com.

"Hairy" solar cells make better photovoltaics?

Materials scientists in the USA and in Germany have come up with methods of growing silicon nanowires in upright fashion on for example an indium tin oxide conductive layer. The wires, coated with either polymer or spun glass, are used as a series of channels to bring electrons more efficiently from the solar cell surface to the electrode.

The technique is one of many being investigated to increase the efficiency of solar cell energy collection that holds the promise of cheap permanent power.

See ecotech daily. Also, Science Daily.

IBM chips at 32nm using High-K/Metal Gate Materials

As you might remember, Intel announced in 01/2007 a new technique for increasing conductivity and transistor isolation using high-k materials. This was curiously followed on the same day by a similar breakthrough announcement from IBM/AMD alliance. Intel is using the high-k technology to improve speed and lower power consumption in its 45nm chips now.

IBM, along with its manufacturing partners, has just demonstrated chips that it says show that high-k/metal gate technology down at typical dimensions of 32nm "can result in performance gains up to 30% and power savings up to 50%", compared to the 45nm process. IBM expects to be manufacturing 32nm systems by the end of 2009

See IBM Press Release.

Graphene may replace silicon in large scale integration

University of Maryland physicists have shown that in graphene the intrinsic limit to the mobility, a measure of how well a material conducts electricity, is higher than any other known material at room temperature.

See U Maryland.

Production targeting 10m2 carbon nanotube sheets

Nanocomp Technologies of Concord, USA says it can now produce sheets of carbon nanotubes that measure 1m by 2m and will reach 10 square metres in area by this summer. The sheets, which the company can produce on its single machine at a rate of one per day, are composed of a series of nanotubes each about a millimeter long, overlapping each other randomly to form a thin mat. The tensile strength of the mat ranges from 200 to 500 megapascals. A sheet of aluminum of equivalent thickness, for comparison, has a strength of 500 megapascals.

See xconomy.com.

New Scanning Microscope identifies atoms as it scans

A new type of scanning transmission electron microscope (STEM) incorporating new aberration-correction technology focuses a beam of electrons on a spot smaller than a single atom -- more sharply and with greater intensity than previously possible. The STEM shoots an electron beam through a thin-film sample and scans the beam across the sample in subatomic steps. The microscope can actually identify atoms using electron energy-loss spectrometry as it scans. Atoms in the path of the beam absorb energy from some of its electrons to kick their own electrons into higher orbits. The amount of energy this takes is different for each kind of atom giving a unique fingerprint.

See Science Daily.

Chinese propose nanotechnology as a "science Megaprojects"

Nanotechnology research is one of four Chinese "science megaprojects" that have the central purpose of catching the country up to US research levels and beyond by 2020 according to a survey by University of California at Santa Barbara researchers who presented their findings on the state of Chinese nanotechnology at the AAAS annual meeting.

See Wired.

3D nanostructures grown using DNA templating

Researchers at the U.S. Department of Energy's Brookhaven National Laboratory have used DNA to guide the creation of three-dimensional, ordered, crystalline structures of nanoparticles. The ability to engineer such 3-D structures is essential to producing functional materials that take advantage of the unique properties that may exist at the nanoscale.

See Science Daily.

Nanowires lead revolutionary change in battery technology

Stanford researchers have used silicon nanowires to revolutionise rechargeable lithium-ion battery technology. Research led by Yi Cui, assistant professor of materials science and engineering, has led to technology that produces 10 times the amount of electricity of existing lithium-ion, known as Li-ion, batteries. A laptop that now runs on battery for two hours could operate for 20 hours.

"It's not a small improvement," Cui said. "It's a revolutionary development."

See Stanford News.

Bacteria produces nanotubes

Researchers from Bourns College of Engineering at the University of California, Riverside, have used Shewanella bacteria, which are metal reducing, to sythesize arsenic-sulfide nanotubes.

See Biophotonics Newsletter.

Major spintronics research breakthrough

"Scientists at the Naval Research Laboratory (NRL) have generated, modulated and electrically detected a pure spin current in silicon, the semiconductor used most widely in the electronic device industry. Magnetic contacts on the surface of an n-type silicon layer enable generation of a spin current which flows separately from a charge current. The spin orientation is electrically detected as a voltage at a second magnetic contact. The relative magnetizations of these contacts allow full control over the orientation of the spin in the silicon channel.

"The electronics industry has relied largely on the control of charge flow, and through size scaling (i.e. reducing the physical size of elements such as transistors) has continuously increased the performance of existing electronics. However, size scaling cannot continue indefinitely as atomic length scales are reached, and new approaches must be developed. Basic research efforts at NRL and elsewhere have shown that spin angular momentum, another fundamental property of the electron, can be used to store and process information in metal and semiconductor based devices."

See EUREKA ALERT, also Spintronics briefing in Scientific American

Nanotechnology health concerns

The Economist has recently run a column on the health concerns behind nanotechnology and the public perception of the area. Good to see these issues getting broader coverage it has to be said. Worth a browse.

See The Economist.

DIT Scientists organise Ireland's first conference on nanotoxicology

DIT's Gordon Chambers and Maria Davoren recently jointly organised Ireland's first conference on nanotoxicology with the Food Safety Authority of Ireland and the Irish Society of Toxicologists. While our bodies have been exposed to naturally occurring nanoparticles throughout our evolution, engineered nanoparticles are a new departure and bring new issues.

From the Irish Times: "Safety is the focus now," says Chambers, whose work looks at how lung cells respond to carbon nanotubes (tiny cylindrical structures) in the lab. "For years people were looking into developing applications for nanoparticles and nanotechnology, but now most people's attention has turned to the safety and biocompatibility of these materials," he says.

See The Irish Times.
(Requires paid subscription or internal DIT access)

RF-STM speeds probe scanning enormously

Scanning Tunneling Microscopes (STM) are capable of imaging lateral distances as small as 1 angstrom and can measure changes in height as small as 0.1 angstrom.

Researchers have found that by adding an external radio frequency (RF) source to the STM setup that they could measure the resistance at the tunneling junction by examining the characteristics of the wave that gets reflected back to the RF source. With knowledge of the junction resistance, the researchers can much more easily deduce the distance between the tip and the surface allowing for 100 to 1000 fold increase in measurement speeds. The researchers who developed this technique have dubbed their modified method as RF-STM.

See arstechnica, original research article in Nature.

Ultrasound from the inside out

Scientists in New Mexico and Taiwan are testing an ultrasound probe about the size of a grain of rice that could offer panoramic views from inside the human body.

The silicon-based device could ultimately be sent through blood vessels in the brain or swallowed like a pill for localised diagnosis.

See NewScientist.

New carbon nanotube fibre outperforms Kevlar

A new type of continuous carbon fibre, developed a group at the Department of Materials Science and Metallurgy at Cambridge, could be woven into super-strong fabric, with potential uses for body armour for the military and law enforcement.

Made from carbon nanotubes, the researchers say their material is already several times stronger, tougher and stiffer than Kevlar fibres currently used to make protective armour.


See BBC News.

Nano effect wins 2007 Nobel Prize in Physics

In 1988 Albert Fert and Peter Grünberg each independently discovered a totally new physical effect – Giant Magnetoresistance or GMR, which was to revolutionise data storage technology that is used to read data on hard disks. With GMR it has been possible to miniaturize hard disks radically in recent years. Sensitive read-out heads are needed to be able to read data from the increasingly compact hard disks used in laptops, iPods and other ever-smaller devices.

GMR can be considered one of the first real applications of nanotechnology. ''The MP3 and iPod industry would not have existed without this discovery,'' Borje Johansson, a member of the Royal Swedish Academy of Sciences told The Associated Press. ''You would not have an iPod without this effect.''

The two winners split the 10M SEK prize (€1.1M).

See nobelprize.org.
Also New York Times.

Silicon nanoparticles boost performance of solar cells

Solar cells coated with a film of 1 nanometer, blue luminescent particles showed a power enhancement of about 60 percent in the ultraviolet range of the spectrum, but less than 3 percent in the visible range, researchers report.

“Integrating a high-quality film of silicon nanoparticles 1 nanometer in size directly onto silicon solar cells improves power performance by 60 percent in the ultraviolet range of the spectrum,” said Munir Nayfeh, a physicist at the University of Illinois and corresponding author of a paper accepted for publication in Applied Physics Letters.

See EurekAlert.