Nanotechnology News

Moved to www.nanotechstate.com

2006-09-19T16:30:00.000-07:00

We got our own domain name www.nanotechstate.com, so from now on you can follow us there. All the articles that were here are already tranferred to Nano Tech State.

Researchers build tiny batteries with viruses

2006-04-07T07:43:00.000-07:00

MIT scientists have harnessed the construction talents of tiny viruses to build ultra-small "nanowire" structures for use in very thin lithium-ion batteries.

By manipulating a few genes inside these viruses, the team was able to coax the organisms to grow and self-assemble into a functional electronic device.

The goal of the work, led by MIT Professors Angela Belcher, Paula Hammond and Yet-Ming Chiang, is to create batteries that cram as much electrical energy into as small or lightweight a package as possible. The batteries they hope to build could range from the size of a grain of rice up to the size of existing hearing aid batteries.

Batteries consist of two opposite electrodes -- an anode and cathode -- separated by an electrolyte. In the current work, the MIT team used an intricate assembly process to create the anode.

Specifically, they manipulated the genes in a laboratory strain of a common virus, making the microbes collect exotic materials -- cobalt oxide and gold. And because these viruses are negatively charged, they can be layered between oppositely charged polymers to form thin, flexible sheets.

The result? A dense, virus-loaded film that serves as an anode.

A report on the work will appear in the April 7 issue of Science.

In their research, the MIT team altered the virus's genes so they make protein coats that collect molecules of cobalt oxide, plus gold. The viruses then align themselves on the polymer surface to form ultrathin wires. Each virus, and thus the wire, is only 6 nanometers (6 billionths of a meter) in diameter, and 880 nanometers in length.

"We can make them in larger diameters," Belcher said, "but they are all 880 nanometers in length," which matches the length of the individual virus particles. And, "once we've altered the genes of the virus to grow the electrode material, we can easily clone millions of identical copies of the virus to use in assembling our batteries.

"For the metal oxide we chose cobalt oxide because it has very good specific capacity, which will produce batteries with high energy density," meaning it can store two or three times more energy for its size and weight compared to previously used battery electrode materials. And adding the gold further increased the wires' energy density, she added.

Equally important, the reactions needed to create nanowires occur at normal room temperatures and pressures, so there is no need for expensive pressure-cooking technology to get the job done... virus battery

Carbon Nanotubes with a Memory

2006-04-03T21:47:00.000-07:00

Carbon nanotubes have successfully been made into a variety of nanoscale circuit components, including transistors, inverters, and switches. Now, a pair of scientists has made a rough, yet promising, flash memory device out of carbon nanotubes. The device is a long way from a finished, marketable product, but it nonetheless represents a significant step in the drive to incorporate carbon nanotubes into mainstream electronics.

“Unlike similar devices that have been made, which use carbon nanotubes but can only operate at very low, very impractical temperatures, our device displays impressive long-term information retention characteristics at room temperature,” said lead researcher Jiyan Dai, a physicist at The Hong Kong Polytechnic University, to PhysOrg.com. “This indicates that mainstream carbon nanotube-based flash memory devices are a real possibility.”

Flash memory devices are currently used to store data in many types of electronic items, including digital cameras, USB memory sticks, and cell phones. Flash memory is considered a “non-volatile” form of memory, meaning it can retain data without a constant supply of power.

A typical flash memory device stores information within a grid of transistors called cells. Each cell consists of three layers: a “control gate” compound and a “floating gate” compound separated by a thin layer of an insulating oxide compound. When a voltage is applied to the cell, electrons build up as negative electric charge in the floating gate. At a certain threshold of charge, the floating gate is considered closed and the cell is thought to have a value of “0.” When the charge drops below that level, the gate is open and the cell has a value of “1.” In this way, each cell is able to hold one bit of information (there are eight bits in one byte).

Dai and co-researcher X.B. Lu created their flash memory device using carbon nanotubes as the charge-storage layer. As described in a paper in the online edition of Applied Physics Letters, they embedded the nanotubes in a compound made of the elements hafnium, aluminum, and oxygen, abbreviated HfAlO, which serves as both the control gate and the oxide layer. This carbon-nanotube “sandwich,” with each layer only several nanometers in thickness, sits on a substrate of silicon.

via http://www.physorg.com/news63291916.html

Nano-welding could join molecular devices

2006-04-01T13:17:00.000-07:00

A nanoscale welding technique has been developed by sparking high-temperature chemical reactions inside "nanopores".

The technique could ultimately be used to weld together nanoscale components and could also lend itself to nanoscopic chemistry experiments, say the researchers.

By lacing a micrometre-thick film of aluminium with nanoscopic holes and filling the holes with iron oxide, the researchers produced a high-temperature "thermite" reaction.

This reaction is used every day in welding and fireworks, and as a simple but spectacular classroom chemistry demonstration. Thermite reactions are normally produced by heating a mixture of aluminium and iron oxide powders, and produce fiery sparks and molten iron.

Etching nanopores

"Instead of just making a wire or a tube like lots of nanotechnology projects, we wanted to actually try and do some chemistry," says Christiaan Richter of Northeastern University in Boston, US, who presented his research at the National Meeting of the American Chemical Society in Atlanta this week.

Richter and colleagues used electrochemical acid etching to create "nanopores" 20 nanometres wide in the surface of aluminium film, at a density of more than a billion per square centimetre.

The pores were made by placing the aluminium film in a solution of weak acid with an electric current running through it. At first, random dimples appear in the aluminium's surface, but if the right current is applied for long enough nanopores form in a regular hexagonal arrangement. This happens due to small differences in electric potential across the surface of the film, which affect the acid solution.

Using a similar electrochemical trick the researchers then filled the nanopores with iron oxide, triggering a reaction that produced temperatures up to 4000°C. nano welding

Using a microwave for synthesis of nanomaterials

2006-03-30T08:27:00.000-07:00

Virginia Commonwealth University chemists, using a simple, commercial microwave oven, have developed a new method for the synthesis of nanomaterials that can control the dimensions and properties of rods and wires that are just one billionth of a meter in size.

The method, known as microwave irradiation, or MWI, is considered a fast and easy way to create highly versatile, tailored nanorods and nanowires to be used in medical applications, drug delivery, sensors, communications and optical devices because microwave heating can provide significant enhancement in reaction rates.

M. Samy El-Shall, Ph.D., professor of chemistry and affiliate professor of chemical engineering at VCU, is discussing his ongoing work of the design, synthesis and characterization of nanoparticles at the American Chemical Society National Meeting & Exposition in Atlanta, March 26-30. In addition, his colleague, Asit Baran Panda, a post-doctoral fellow in the VCU Department of Chemistry, will present this study.

“The synthesis of new materials made of particles, rods and wires with dimensions in the nanometer scale is among the most active areas of research in science due to the unique properties of these materials compared to conventional materials made from micron sized particles,” said El-Shall, who is lead author of the study.

“MWI is unique in providing scaled-up processes thus leading to a potentially important industrial advancement in the large-scale synthesis of nanomaterials,” said El-Shall...

news release

Cerium oxide nanotubes get noticed

2006-03-29T10:06:00.000-07:00

Chemists and materials scientists often study "nanotubes" -- capsule-shaped molecules only a few billionths of a meter in width. In nanotube form, many materials take on useful, unique properties, such as physical strength and excellent conductivity. Carbon nanotubes are the most widely investigated variety. Now, in pioneering research, scientists at the U.S. DoE's Brookhaven National Laboratory have created and investigated the properties of nanotubes made of a different, yet equally interesting material: cerium oxide.

"Cerium oxide nanotubes have potential applications as catalysts in vehicle emission-control systems and even fuel cells," says Brookhaven chemist Wei-Qiang Han, the lead scientist involved in the work. "But until very recently, they haven't been studied."

Han and his colleagues are in the midst of ongoing research into the structure and properties of cerium oxide nanotubes. As part of this, they have devised a method to synthesize cerium oxide nanotubes of high quality. First, they allow the compounds cerium nitrate and ammonia hydroxide to chemically react. Initially, this reaction forms "one-dimensional" nanostructures, such as rods and sheets, made of the intermediate product cerium hydroxide. The intermediate product is then quickly cooled to zero degrees Celsius, which freezes those structures into place. By letting the chemical reaction proceed over a long period of time, a process called "aging," the hydrogen is eventually removed from the intermediate product and a large quantity of the desired end product -- cerium oxide nanotubes -- is formed... cerium oxide nanotubes

Center For Responsible Nanotechnology Engages Leading Experts To Discuss Nanotech's Impact

2006-03-27T15:31:00.000-07:00

The Center for Responsible Nanotechnology (CRN) today announced its first series of new research papers in which industry experts predict profound impacts of nanotechnology on society. Eleven original essays by members of CRN's Global Task Force appear in the latest issue of the journal Nanotechnology Perceptions, published today. From military and security issues to human enhancement, artificial intelligence, and more, these papers give readers a peek under the lid of Pandora's box to see what the future might hold.

Ray Kurzweil, renowned inventor, entrepreneur, and best-selling author, explained, "As the pace of technological advancement rapidly accelerates, it becomes increasingly important to promote knowledgeable and insightful discussion of both promise and peril. I'm very pleased to take part in this effort by including my own essay, and by hosting discussion of these essays on the 'MindX' discussion board at KurzweilAI.net."

Nanotechnology Perceptions is a peer-reviewed academic journal of the Collegium Basilea in Basel, Switzerland. "We jumped at the chance to publish the CRN Task Force essays," said Jeremy Ramsden, editor-in-chief of the journal. "To us, these papers represent world-class thinking about some of the most important challenges that human society will ever face."

In August 2005, the Center for Responsible Nanotechnology, a non-profit research and advocacy organization, formed its Global Task Force to study the societal implications of molecular manufacturing, an advanced form of nanotechnology. Bringing together a diverse group of world-class experts from multiple disciplines, CRN is spearheading an historic, collaborative effort to develop comprehensive recommendations for the safe and responsible use of this rapidly emerging technology... read

New 3D Magnetic Tweezers

2006-03-27T09:42:00.000-07:00

Professor Gwo-Bin Vincent Lee, from National Cheng Kung University, Taiwan, and his colleagues have manufactured three-dimensional, micromachined magnetic tweezers to manipulate DNA molecules. Their method was published in the February 7, 2006 issue of Nanotechnology.

"This study could provide a provide a powerful tool for exploring the bio-physical properties of biomolecules, bio-polymers and cells," Lee said.

Lee's team made magnetic tweezers from six, hexagonal micro-electromagnets. The scientists wrapped three-dimensional coils, with a width of 80 um, spacing of 100 um, and thickness of 25 um, 30 times around a permalloy core. They chose permalloy because it magnetizes and demagnetizes with low-magnetic field strength.

The type of DNA was likewise important to the study's success. The team used λ-phage DNA, which had two complementary 12-base, single-stranded 5' overhangs. "These overhangs allow phage DNA to easily be derivatized with various functional groups by base-pairing with a complementary sequence," Lee explained. Each base pair of DNA was 0.34nm, without any external force.

The scientists colored the DNA with a green dye, keeping the base pair to dye molecule ratio at 5 to 1, in order to have a high signal-to-noise ratio. "Since a DNA molecule only has a 2nm thickness, we can't observe it with a normal optical microscope," Lee said. The dye allowed the team to view DNA under a fluorescent microscope.

An important element to Lee's study was a microfluidic channel integrated with the magnetic tweezers. This channel had a width of 5mm, height of 60um, and length of 2cm. "We sealed the microfluidic channel with a glass cover slip (100um thick), using double-sided sticky tape (60um thick)."

"The microfluidic channel allowed us to observe a single DNA molecule in real-time," Lee stressed. "We introduced the DNA by pressuring it with a syringe pump into the channel."

Another element to the study was what to use on DNA extremities. "A DNA specific-end anchoring must meet several rigorous requirements, including specific binding, binding strength, localized binding, and complexity level of the procedure," Lee said... nano magnetic tweezers

New Material Could Have Applications For Microelectronics, Drug Delivery Systems

2006-03-23T23:16:00.000-07:00

A new study by chemists and engineers at the University of Toronto describes a nanoscale material they’ve created that could help satisfy society’s never-ending hunger for smaller digital devices and cellphones, and could even lead to new methods for delivering medications via skin patches.

The material, known as periodic mesoporous organosilica (PMO), is a thin film interspersed with pores just two-billionths of a metre across. The team created it by mixing an organosilica precursor (silica glass, containing organic groups) with a surfactant — essentially, a soap that mixes oil and water — which causes the organosilica to self-assemble into a nanostructure. The scientists then washed away the surfactant to leave a nanoporous material. When they examined the thin film that remained, they discovered that it made an excellent insulator that could be used to separate tiny wires inside microelectronics.

“It demonstrates how creative chemistry can lead to really interesting engineering — it’s a good marriage,” says Benjamin Hatton, who led the work while he was a PhD candidate working with both the Departments of Chemistry, with supervisor Professor Geoffrey Ozin, and Materials Science and Engineering, with supervisor Professor Doug Perovic. “Technology can develop in unexpected ways, and what we’ve found here could lead to developments in microelectronics or drug delivery systems.”

Conventionally, computer chip manufacturers have insulated their wire connections with silica glass, preventing them from coming into contact and interfering, with each other. But the PMO film described in this study acts as a better insulator and would take up far less room, allowing components to shrink even further. “Industry is always looking for a better insulator,” Hatton says. “This is an example of how materials chemistry can provide innovative solutions to the design of novel materials.”... nanoscale materials

Nanoelectronics roadmap aims to speed commercialization

2006-03-23T17:06:00.000-07:00

The IEEE launched an Nanoelectronics Standards Roadmap initiative Tuesday (March 21) to forge industry standards for nanotechnology.

The effort is designed to move nanoelectronics innovations from laboratory to the marketplace for applications ranging from communications, information technology, consumer products and optoelectronics.

IEEE will host a roadmap workshop on May 18 in New York to define the scope and timing of the standards.

Roadmap work will be led by a steering committee representing diverse segments of the nanoelectronics community, including materials and device developers, nanoelectronics integrators along with regulatory concerns.

The workshop, colocated with the Nano-Business Conference, will build on the IEEE-SA (Standards Association) nanoelectronic standards framework for nanomaterials, devices, functional blocks and applications. Plans call for a first draft of the roadmap for presentation at a second workshop in October and publication at the end of 2006. The roadmap will be updated annually.

According to Nathan Tinker, roadmap coordinator and co-founder of the Nano-Business Alliance trade organization, "The IEEE roadmap will help the industry prioritize the standards it needs and focus its resources." Tinker added that the roadmap will supplement other technology blueprints like the International Technology Roadmap for Semiconductors and the International Electronics Manufacturing Initiative.

IEEE-SA said a broad nanoelectronic roadmap builds on similar efforts targeting carbon nanotube technology. The 2003 effort yielded several standards activities, including the recently approved IEEE 1650, "Standard Test Methods for Measurement of Electrical Properties of Carbon Nanotubes." The first-ever nanoelectronics standard provides a common template for generating reproducible electrical data on nanotubes... via

First images of flowing nano ripples

2006-03-22T08:09:00.000-07:00

TU Delft Researchers have shed new light on the formation of nanoscale surface features, such as nano ripples. These features are important because they could be useful as templates for growing other nanostructures. The scientific journal Physical Review Letters published an article this week on the research in Delft.

Some remarkable geometrical features may appear for instance on a glass surface when it is bombarded with ions, such as triangular patterns and ripples. Scientists study nano ripples and other geometrical features created by bombarding a surface with a beam of ions because of their potential as a template for growing other specific nanostructures. If they want to exploit this potential, they will first need a thorough understanding of the creation and evolution of geometrical features of this kind.

A scientific explanation of the ripples was given fifteen years ago. It was already known that surfaces wear quickly when they are bombarded. The erosion is stronger in the valleys of the ripples than in other places, so the valleys get deeper as time passes.

But the nano ripples do not continue to grow indefinitely. The bombardment liquefies the upper layer of the material, so that it flows from the peaks into the valleys.

No one has ever seen this actual flow until now, only the final result: the partly-filled ripple patterns. Dr Paul Alkemade, a researcher at the Kavli Institute of Nanoscience of Delft University of Technology became the first person to watch this flow using an electron microscope incorporating an ion beam... nano ripples

Nano Image of the Day - Mar 21st 2006

2006-03-21T08:06:00.000-07:00

The "nano-flowers" are created by varying the temperature and pressure of a chemical process.

Tiny representations of flowers and trees that are a fraction of the width of a human hair have been created by scientists in Cambridge, UK.

The nano-sized plants are "grown" from tiny droplets of the liquid form of the metal gallium on a silicon surface.

The scientists then expose the droplets to a gas containing methane and a reaction causes the gas to condense to form tiny wires of silicon carbide.

The images appear in the Institute of Physics journal Nanotechnology.

By varying the temperature and pressure of the growth process the wires can be fused together to form a variety of complex shapes in the range of 1-5 microns (millionths of a metre)... source

The road to nanomedicine may not always be quick or easy

2006-03-21T07:57:00.000-07:00

Of the six volunteers who became seriously ill during a drug trial last week, four, mercifully, seem to be beginning to recover, while two are still critical, according to the most recent BBC news story. It’s still too early to be sure what went so tragically wrong; there are informative articles, with some informed comment, on the websites both of New Scientist and Nature. What we should learn from this is that even as medicine gets more sophisticated and molecularly specific, many things can go wrong in the introduction of new therapies. The length of time it takes new treatments to get regulatory approval can be frustratingly, agonisingly long, but we need to be very careful about the calls we sometimes hear to speed these processes up. The delays are not just gratuitous red tape.

The drug behind this news story was developed by a small, German company, TeGenero immunotherapeutics. It’s a monoclonal antibody, code-named TGN1412; a protein molecule which specifically binds to a receptor molecule on T-cells, a type of white blood cell which is central to the body’s immune response. The binding site - code-named CD28 - is a glyco-protein - a combination of a protein with a carbohydrate segment - which provides the signal to activate the T-cells. What’s special about TGN1412 is that the action of this drug alone is sufficient to activate the T-cells; normally simultaneous binding to two different receptors is required. It’s as if TGN1412 overrides the safety catch, allowing the T-cells to be activated by a single trigger. It’s these activated T-cells that then carry out the therapeutic purpose, killing cancer cells, for example.

Few people have connected these events with bionanotechnology (an exception is the science journalist Niels Boeing in this piece on the German Technology Review blog). There are now a number of monoclonal antibody based drugs in clinical use, and they are not normally considered to be the product of nanomedicine... nanomedicine

Virus used to make nanoparticles

2006-03-19T22:01:00.000-07:00

UK scientists from Norwich have used a plant virus to create nanotechnology building blocks.

The virus, which infects black-eyed peas, was employed as a "scaffold" on to which other chemicals were attached.

By linking iron-containing compounds to the virus's surface, the John Innes Centre team was able to create electronically active nanoparticles.

The researchers tell the journal Small that their work could be used in the future to make tiny electrical devices.

The work is yet another example of how scientists are now trying to engineer objects on the scale of atoms and molecules.

At the nanoscale, materials can be "tuned" to display unusual properties that could be exploited to build faster, lighter, stronger and more efficient devices and systems.

Stores charge

The mosaic virus used in the experiments infects black-eyed pea plants (Vigna unguiculata), causing their leaves to become mottled and yellow.

Not infectious to humans or animals, the miniscule virus measures just 30 nanometres across - where one nanometre is a billionth of a metre... virus used to make nanoparticles

A New Process Allows Growing Carbon Nanotubes Directly onto MEMS

2006-03-18T21:45:00.000-07:00

Researchers in Switzerland have successfully integrated carbon nanotubes (CNTs) directly into a polysilicon chip. This technique is opening the way towards NEMS and CNT based system integration and the synthesis and evaluation of mechanical nano-scale transducers based on CNTs.

Researchers in Switzerland have successfully integrated carbon nanotubes (CNTs) directly into a polysilicon chip. This technique is opening the way towards NEMS and CNT based system integration and the synthesis and evaluation of mechanical nano-scale transducers based on CNTs.

The group reports their findings titled "Process integration of carbon nanotubes into microelectro- mechanical systems" (article in press) in the Jan.20, 2006 online edition of Sensors and Actuators A: Physical. In this paper they describe the process flow and characterization of their novel approach to integrate nanotube growth into batch fabricated MEMS.

Alain Jungen, researcher and author of the study and Christofer Hierold, professor of Micro- and Nanosystems at the ETH Zurich, explained:

"In our paper we demonstrate a new process allowing direct synthesis of carbon nanotubes onto MEMS. The MEMS chips were successfully post-processed with electron beam lithography combined with lift-off of catalyst layers."

"With our novel process, individual or multiple tubes can be directly grown between movable posts and electrically connected. This way direct and reliable measurement techniques can be developed and used to accelerate research and evaluation of nanotube transducer properties."

CNTs are arguably the most studied nanomaterials in recent years due to their fascinating physical properties. Apart from their hardness and toughness they have demonstrated exceptionally high thermal conductivity, eventually exhibiting a property known as "ballistic conduction." This makes them ideal candidates for highly integrated electromechanical nanosystems (NEMS).

In developing NEMS major challenges still need to be overcome, foremost controlled and reproducilble integration of the tubes by local growth or self-assembly and the fundamental characterization of electromechanical effects in carbon nanotubes. Only then can CNT-based NEMS become a reality.

A research project in Hierold's group, called "Integrated nano transducers: fundamental characterization of electromechanical effects in carbon nanotubes" is focussing on exactly this problem area... via

UCR Researchers Grow Bone Cells on Carbon Nanotubes

2006-03-17T18:12:00.000-07:00

Researchers at the University of California, Riverside have published findings that show, for the first time, that bone cells can grow and proliferate on a scaffold of carbon nanotubes.

The paper, titled Bone Cell Proliferation on Carbon Nanotubes, appears in the March 8 edition of Nano Letters, a journal of the American Chemical Society. Lead author, Laura Zanello, is an assistant professor of biochemistry at UCR and was joined by UCR colleagues, graduate students Bin Zhao and Hui Hu, and Robert C. Haddon, distinguished professor of chemistry and of chemical and environmental engineering.

Zanello’s paper builds on previous research by Haddon which showed that carbon nanotubes could be chemically compatible with bone cells.

Zanello’s experiment put Haddon’s findings to the test and found that the nanotubes, 100,000 times finer than a human hair, are an excellent scaffold for bone cells to grow on.

“In the past scientists have been plagued by toxicity issues when combining carbon nanotubes with living cells,” Zanello said. “So we have been looking for the most pure nanotubes we could get to reduce the presence of heavy metals that are frequently introduced in the manufacturing process.”

She credited Haddon’s graduate student Zhao, now a postgraduate researcher at the Oak Ridge National Laboratory, with manufacturing highly pure nanotubes for her to work with.

Some of the carbon nanotubes were chemically treated and others were not, then they were combined with rat bone cells to determine which combination or combinations worked best. Non-treated and electrically-neutral nanotubes emerged as the best scaffolds for bone growth.

Because carbon nanotubes are not biodegradable, they behave like an inert matrix on which cells can proliferate and deposit new living material, which becomes functional, normal bone, according to the paper. They therefore hold promise in the treatment of bone defects in humans associated with the removal of tumors, trauma, and abnormal bone development and in dental implants, Zanello added.

More research is needed to determine how the body will interact with carbon nanotubes, specifically in its immune response, the paper states.

“We hope to look at the atomic interactions between living matter and synthetic scaffolds so we can come up with material that can interact at the nanolevel with living cells,” Zanello said... bone cells grow on carbon nanotubes

Nanotech discovers the Americas

2006-03-16T13:55:00.000-07:00

It is without question the smallest map that has ever been made.

US scientists have coaxed strands of DNA, the molecule that holds the "code of life", to take up a shape that resembles the Americas.

The mini-map measures just a few hundred nanometres (billionths of a metre) across, smaller even than some bacteria - a scale of 1:200 trillion.

Paul Rothemund, from the California Institute of Technology, and colleagues report their cartography in Nature.

They tell the journal their technique could find uses in the emerging field of nanotechnology, which aims to develop novel materials, devices and systems by manipulating individual atoms and molecules.

The team's work exploits the very particular bonding that takes place in DNA.

Each strand of the molecule will have a sequence of chemical components, or bases, which will only attach themselves to a complementary code of another DNA strand (see box).

The researchers made long single strands of DNA that could be folded back and forth, tracing a mazelike path, to form a scaffold that filled up the outline of any desired shape. new method for folding DNA strands

Rice University researchers create 'nanorice'

2006-03-15T09:30:00.000-07:00

Who better to invent "nanorice" than researchers at Rice University? But marketing and whimsy weren't what motivated the team of engineers, physicists and chemists from Rice's Laboratory for Nanophotonics (LANP) to make rice-shaped particles of gold and iron oxide.

"On the nanoscale, the shape of a particle plays a critical role in how it interacts with light," said LANP Director Naomi Halas. "We were looking for a new shape that would combine the best properties of the two most optically useful shapes – spheres and rods. It's just a coincidence that that shape turned out to look exactly like a grain of rice."

Nanoparticles like nanorice can be used to focus light on small regions of space. Rice's scientists plan to capitalize on this by attaching grains of nanorice to scanning probe microscopes. By moving the grains next to proteins and unmapped features on the surfaces of cells, they hope to get a far clearer picture than what's available with current technology.

The nanorice research will appear in the April 12 issue of Nano Letters. Halas will discuss the findings at 11:30 a.m. today at a press conference at the American Physical Society's 2006 March Meeting in room 334 of the Baltimore Convention Center.

In form, nanorice is similar to nanoshells, a spherical nanoparticle Halas invented in 1998 that is currently being examined for possible applications in molecular imaging, cancer treatment, medical diagnostics and chemical sensing. Both nanorice and nanoshells are made of a non-conducting core that is covered by a metallic shell.

Halas' investigations find that nanorice possesses far greater structural tunability than nanoshells and another commonly studied optical nanoparticle, the nanorod. In fact, tests indicate that nanorice is the most sensitive surface plasmon resonance (SPR) nanosensor yet devised.

Research over the past decade has shown that nanoscale objects can amplify and focus light in ways scientists never imagined. The "how" of this involves plasmons, ripples of waves in the ocean of electrons that flow constantly across the surfaces of metals. When light of a specific frequency strikes a plasmon that oscillates at a compatible frequency, the energy from the light is converted into electrical energy that propagates, as plasmons, through the nanostructure.

Changing the shape of a metal at the nanoscale allows engineers and scientists to modify the properties of these plasmon waves, controlling the way that the metal nanostructure responds to light. Because of this, metal nanostructures can have beautiful, vivid colors that depend on their shape. Some nanoscale structures -- like nanorice and nanoshells -- act as superlenses that can amplify light waves and focus them to spot sizes far smaller than a wavelength of light.

In January 2005, for example, Halas and colleagues showed that nanoshells were about 10,000 times more effective at Surface-enhanced Raman Scattering (SERS) than traditional methods. Raman scattering is a type of spectrographic technique used by medical researchers, drug designers, chemists and others to determine the precise chemical makeup of materials... nanorice

Nanotech helps blind hamsters see

2006-03-14T09:56:00.000-07:00

Nanotechnology has restored the sight of blind rodents, a new study shows.

Scientists mimicked the effect of a traumatic brain injury by severing the optical nerve tract in hamsters, causing the animals to lose vision.

After injecting the hamsters with a solution containing nanoparticles, the nerves re-grew and sight returned.

Writing in the Proceedings of the National Academy of Sciences, the team hopes this technique could be used in future reconstructive brain surgery.

Ultimate challenge

Repairing nerve damage in the central nervous system after injury is seen as the ultimate challenge for neuroscientists, but so far success in this field has been limited.

Nerve regeneration is set back by a number of factors, including scar tissue and gaps in brain tissue caused by the damage. And this can make treatment by medical and surgical methods very difficult.

To find a novel way around these problems, the team based at Massachusetts Institute of Technology (MIT), US, and Hong Kong University looked towards nanotechnology - a branch of science involving the manipulation of atoms and molecules.

The researchers injected the blind hamsters at the site of their injury with a solution containing synthetically made peptides - miniscule molecules measuring just five nanometres long.

Once inside the hamster's brain, the peptides spontaneously arranged into a scaffold-like criss-cross of nanofibres, which bridged the gap between the severed nerves... nanotechnology helps blind hamsters

I, Nanobot

2006-03-13T17:07:00.000-07:00

A pessimistic as well as a futuristic article by Alan H. Goldstein. An interesting read I must say. And I don't agree with 99% of what is said in there...

...In fact, we have put into motion research that will create every component necessary to build an animat. One formula is as simple as A + B + C.

A = Nanobiotechnology devices that can survive and function inside human beings. Many therapeutic devices in development for drug delivery, cancer therapy, etc., are designed to survive in the physicochemical environment of the body.

B = Nanobiotechnology devices that can derive energy from biological metabolism. Many nanomedical devices will be powered by the fuel available inside the human body. A common idea is to take our own glucose-oxidizing enzymes and use them as a fuel cell for the nanobiobot.

C = Nanobiotechnology devices capable of copying themselves by molecular self-assembly.

Which creates a completely realistic animat formula. A + B + C = a self-replicating nanobiobot capable of living inside the human body powered by our own metabolic energy.

Of course, scientists are not intentionally putting A together with B and C. No one is trying to create the first true animat -- they're just working on rudimentary forms of artificial life or synthetic biology. But if, as part of this benign research initiative, they happen to create nanobiobots some of which have traits A or B or C -- our definition of life will have changed forever.

Does this mean we will immediately cease to be human? Probably not. The most probable scenario is that an array of proto-animats will be carried as an evolutionary adaptation that enhances biological function for generations before any of them become an essential part of our phenotype. After that...

If the animat test described here is not sufficient, let it stand as a challenge for the development of a completely rigorous test for the unequivocal identification of nonbiological life forms. The larger point is that humanity must initiate a search-and-test protocol now in order to prepare for the arrival of the literal alien from within.

Nanofabricated animats may be infinitessimally tiny, but their electrons will be exactly the same size as ours -- and their effect on human reality will be as immeasurable as the universe. Like an inverted SETI program, humanity must now look inward, constantly scanning technology space for animats, or their progenitors. The first alien life may not come from the stars, but from ourselves. read

Canine Parvovirus-Like Particles, A Novel Nanomaterial for Tumor Targeting

2006-03-12T17:17:00.000-07:00

Empty virus particles have shown promise as potential nanoscale drug carriers that can be modified chemically to display tumor-targeting molecules (click here for earlier story). Now, investigators at The Scripps Research Institute have shown that canine parvovirus nanoparticles, which bind to a receptor that is overproduced by some types of malignant cells, will naturally target tumors.

Writing in the Journal of Nanobiotechnology, a team led by Marianne Manchester, Ph.D., describes its studies aimed at determining whether mass-produced, non-infectious canine parvovirus nanoparticles might be suitable as a tumor-targeting drug delivery vehicle through the particles’ natural interaction with transferrin, a receptor that carries iron into cells. The reproducible size and chemical makeup of virus-based nanoparticles, combined with the relative ease of manufacturing them in large quantities, make them possible winners in the drive to develop nanoparticulate drug carriers for cancer therapy. Such laudable properties are only of use, however, if these protein nanoparticles can be modified to carry small molecules into tumor cells.

The investigators began by analyzing the structure of protein that assembles into viral nanoparticles. This evaluation showed that there should be at least two, and perhaps as many as six, amino acids on the surface of this protein that should be available to react chemically with small drug molecules or imaging agents. Since 60 copies of this protein come together to form the final virus nanoparticle, the investigators reasoned that it should be relatively straightforward to attach clinically useful molecules to the virus nanoparticles... via

Nanotechnology Could Improve Satellites and Solar Cells

2006-03-11T13:58:00.000-07:00

More efficient space solar cells could mean better imagery satellites and improved solar energy technology.

Scientists at the NanoPower Research Labs at Rochester Institute of Technology, led by director Ryne Raffaelle, are using nanotechnology to explore this possibility through a project funded by an $847,109 grant from the U.S. Department of Defense. The project aims to take current state-of-the-art solar cells used for space power to the next level by developing nanostructured materials and, ultimately, by producing nanostructured cells. The program may extend to three and half years, with total funding reaching $3 million.

“If successful, the results of this program will improve current solar array and satellite technology, and lay the foundation for long-term improvement in our ability to use solar energy,” Raffaelle says.

Unique to this project is the ability to exploit the fundamental behavior of nanoscale crystals, also known as quantum dots, which alter the way a solar cell absorbs light and converts it into electricity. According to Raffaelle, the electrical, optical, mechanical and even thermal properties of nanomaterials can be controlled by changing the particle size, making them highly useful in semiconductor device development.

Today’s current solar-cell technology used for space power relies upon three individual photovoltaic junctions used in a series. These so-called triple-junction solar cells—consisting of the chemical compounds, germanium, gallium arsenide and indium gallium phosphide—are grown latticed-matched on top of one another. Raffaelle’s team will augment the middle cell in the three-layered sandwich with a quantum dot array to enhance its short-circuit current and improve the overall efficiency of the triple junction cell... space solar cells

Nano Image of the Day - Mar 10th 2006

2006-03-10T11:37:00.000-07:00

Transmission electron microscopy shows nano-sized particles that form when fullerenes clump together in water. Research is showing what factors affect particle size.

Fate of Nano Waste: Researchers Study How to Make Nanomaterial Industry Environmentally Sustainable
... Researchers picked fullerenes, molecules composed of 60 carbon atoms, as their model carbon-based nanomaterial. Fullerenes have a potentially broad range of applications, including their use in pharmaceuticals, as lubricants, as semiconductors and in energy conversion. Mass commercial production of fullerenes may get under way internationally in just two years.

“This research is providing the information to make practices sustainable when fullerene production comes on line,” said John Fortner, a Georgia Tech research scientist and Rice University Ph.D. student. “It’s our goal to minimize environmental impact in contrast to the pollution caused in the past by, for example, dry cleaning industry practices... nanowaste

Experimental Atomic Clock Uses Ytterbium ‘Pancakes’

2006-03-10T11:31:00.000-07:00

Scientists at the National Institute of Standards and Technology (NIST) working with Russian colleagues have significantly improved the design of optical atomic clocks that hold thousands of atoms in a lattice made of intersecting laser beams. The design, in which ytterbium atoms oscillate or “tick” at optical frequencies, has the potential to be more stable and accurate than today’s best time standards, which are based on microwaves at much lower frequencies. More accurate time standards could improve communications, enhance navigation systems, and enable new tests of physical theories, among other applications.

Described in two papers in the March 3 issue of Physical Review Letters,* the heart of the clock consists of about 1,000 pancake-shaped wells made of laser light and arranged in a single line, each containing about 10 atoms of the heavy metal ytterbium. The lattice design results in fewer systematic errors than optical atomic clocks using moving balls of cold atoms, and also offers advantages in parallel processing over other approaches using single charged atoms (ions). The optical lattice, created by an intense near-visible laser beam, is loaded by first slowing down the atoms with violet laser light and then using green laser light to further cool the atoms so that they can be captured. Scientists detect the atoms’ “ticks” (518 quadrillion per second) by bathing them in yellow light at slightly different frequencies until they find the exact “resonant” frequency (or color) that the atoms absorb best.

Previous lattice-based clocks have used atoms with odd-numbered atomic masses, which have a nuclear magnetic field that causes some additional complications. The new clock uses atoms with even-numbered atomic masses that have no net nuclear magnetic field but have been difficult to use in atomic clocks until now. The researchers found they could apply a small external magnetic field combined with yellow laser light to induce an otherwise “forbidden” oscillation between two energy levels in the atoms. The team reported an extremely precise resonance frequency with a strong signal that demonstrates the clock’s potential for very high stability. The new approach is also applicable to other atoms with even-numbered atomic masses, such as strontium and calcium, which are under study at NIST and other research laboratories around the world... atomitc clock with ytterbium

Nanoparticles create biocompatible capsules

2006-03-08T08:39:00.000-07:00

An innovative strategy of mixing lipids and nanoparticles to produce new drug and agricultural materials and delivery vehicles has been developed by researchers at the University of Illinois at Urbana-Champaign.

“This is a new way to make nano-size capsules of a biologically friendly material,” said Steve Granick, a professor of materials science and engineering, chemistry and physics. “The hollow, deformable and biofunctional capsules could be used in drug delivery, colloidal-based biosensors and enzyme-catalyzed reactions.”

Lipids are the building blocks of cell membranes. The construction of useful artificial lipid vesicles was previously not possible, because the vesicles were too delicate. Granick and graduate student Liangfang Zhang found a way to stabilize lipids and stop their destruction. The researchers describe their technique in a paper accepted for publication in the journal Nano Letters, and posted on its Web site.

To stabilize lipids, the researchers begin by preparing a dilute solution of lipid capsules of a particular size. After encapsulating chemicals in the capsules or adsorbing molecules on their surfaces, they add charged nanoparticles to the solution. The nanoparticles adhere to the capsules and prevent further growth, freezing them at the desired size. The lipid concentration can then be increased without limits.... biocompatible nano capsules

Towards entangled-photon LEDs

2006-03-07T10:25:00.000-07:00

Scientists in the UK have been able to generate pairs of entangled photons from a nanoscale crystal of semiconductor known as a "quantum dot" far more efficiently than was possible before. The breakthrough was made by Andrew Shields at Toshiba and colleagues at the University of Cambridge, who produced entangled photons with an efficiency of 70% -- compared to a previous best figure of 49%. The improved performance approaches that required for useful applications, which means that devices emitting entangled light could one day be as common as lasers and light-emitting diodes.

Entanglement allows particles to have a much closer relationship than is possible in classical physics, and means that we can know the state of one photon by measuring the state of the other. For example, if one photon is horizontally polarized, then its entangled counterpart must have a vertically polarized spin, even if it is many kilometres away. In the source made by Shields and colleagues, correlation is seen for not only horizontal and vertical polarizations but also for all possible directions of polarization.

The team produced entangled photons from a crystal just 12 nm in diameter made from indium arsenide embedded within a gallium arsenide and aluminium arsenide cavity. When excited by a laser pulse, the quantum dot captures two electrons and two holes to form a "biexciton" state in the dot. One of the electrons recombines with a hole to create a photon, leaving behind an intermediate "exciton" state in the dot of one electron and one hole. The other electron-hole pair then combines to create a second photon... entangled-photon LEDs

Nano Image of the Day - Mar 6th 2006

2006-03-06T08:28:00.000-07:00

Silicon staircase.
Steps of silicon serve as a natural ruler for measuring vertical dimensions. This silicon "target" has step heights ranging from tens to hundreds of nanometers leading down to a flat, single atomic layer measuring only 0.3 nanometer. The microscope used to make this image sits on an isolated concrete slab equipped with air springs to cancel out even minute vibrations that could ruin the nanoscale measurements.

A Toxicologic Review of Quantum Dots: Toxicity Depends on Physicochemical and Environmental Factors

2006-03-06T08:17:00.000-07:00

As a growing applied science, nanotechnology has considerable global socioeconomic value, and the benefits afforded by nanoscale materials and processes are expected to have significant impacts on almost all industries and all areas of society. A diverse array of engineered nanoscale products and processes have emerged [e.g., carbon nanotubes, fullerene derivatives, and quantum dots (QDs)], with widespread applications in fields such as medicine, plastics, energy, electronics, and aerospace. With the nanotechnology economy estimated to be valued at $1 trillion by 2012, the prevalence of these materials in society will be increasing, as will the likelihood of exposures. Importantly, the vastness and novelty of the nanotechnology frontier leave many areas unexplored, or underexplored, such as the potential adverse human health effects resulting from exposure to novel nanomaterials. It is within this context that the need for understanding the potentially harmful side effects of these materials becomes clear. The reviewed literature suggests several key points: Not all QDs are alike; engineered QDs cannot be considered a uniform group of substances. QD absorption, distribution, metabolism, excretion, and toxicity depend on multiple factors derived from both inherent physicochemical properties and environmental conditions; QD size, charge, concentration, outer coating bioactivity (capping material and functional groups), and oxidative, photolytic, and mechanical stability have each been implicated as determining factors in QD toxicity. Although they offer potentially invaluable societal benefits such as drug targeting and in vivo biomedical imaging, QDs may also pose risks to human health and the environment under certain conditions... toxicity of quantum dots

Nano Image of the Day - Mar 3rd 2006

2006-03-03T08:07:00.000-07:00

Colorized micrograph of a nanoporous insulation film after “wrinkling” with a new NIST measurement method. The method measures the strength and stiffness of a thin-film sample in about 2 seconds, as compared with several minutes for indentation and other conventional approaches. In addition, the NIST-developed technique accommodates high-throughput testing, so that hundreds or even a few thousand systematically varying samples can be tested in rapid succession.

Accelerated testing could spur progress in a large variety of existing and emerging technology areas that rely on thin-film advances for improved performance or enhanced protection. Examples include semiconductors, solar cells, fuel cells, coatings, magnetic storage devices and prospective nanotechnology devices.

The new method entails mounting a postage-stamp-sized assortment of incrementally varying thin films on a strip of silicone rubber about the size of a Band-Aid. Placed on a custom-built stage, the combination of sample array and soft substrate then is stretched or compressed. At a critical point of instability, a sample buckles, wrinkling like a piece of corrugated cardboard... advanced thin films

New nano-finding points to new computer technologies based on magnetic spin

2006-03-03T08:00:00.000-07:00

An unusual pool of scientific talent at the U.S. Department of Energy's Argonne National Laboratory, combined with new nanofabrication and nanocharacterization instruments, is helping to open a new frontier in electronics, to be made up of very small and very fast devices.

A new discovery by this group opens a path to new computer technologies and related devices, and could drive entire industries into the future, the researchers say.

The researchers learned that swirling spin structures called magnetic vortices, when trapped within lithographically patterned ferromagnetic structures, behave in novel ways. In a nickel-iron alloy, the two vortices swirl in opposite directions, one clockwise and the other counterclockwise. However, the researchers discovered that the magnetic polarity of the central core of the vortices, like the eye of a hurricane, controlled the time-evolution of the magnetic properties, not the swirling direction.

The material being studied is about one micron in size, and the area of the vortex core is about 10 nanometers in size. For comparison, the period at the end of this sentence is about 100 microns or 100,000 nanometers in diameter.

Group leader Sam Bader, an Argonne scientist for more than 30 years, explained that the work could lead to the next generation of electronic devices. “When the first computer hard disk was introduced 50 years ago, it required a rather large size to store each bit of digital information. On today's computer disks, the corresponding size is about one-50-millionth of that needed in the original disks. We are now moving well into the nanoscale range, and nanomagnetism is one of the real drivers of the nanotechnology field.”... nano magnetic spin

Nano Image of the Day - Mar 2nd 2006

2006-03-02T08:36:00.000-07:00

Array of vertically aligned carbon nanotubes grown using plasma enhanced chemical vapor deposition is intercalated with copper to create a composite which exhibits good thermal properties ideal for chip cooling. source

Nanocrystals amplify light

2006-03-02T08:28:00.000-07:00

Physicists have found a new way to amplify light that could make lasers more efficient. Chris Phillips at Imperial College in London and colleagues at the University of Neuchâtel in Switzerland made the breakthrough using specially patterned nanocrystals that behave as artificial atoms. Because the separation between energy levels in their crystals can be controlled, laser light can be produced without the need for a population inversion. The technique could also find applications in optical data storage and even allow materials to become completely transparent (Nature Materials 5 175).

The active medium in a laser is usually a gas or a crystal in which the atoms have been excited or "pumped" so that more electrons exist in the upper of two energy levels. Once such a population inversion has been achieved, a beam of light passing through the medium can stimulate electrons to fall into the lower energy level and emit a photon of the same wavelength. The emitted photons then go on to de-excite further atoms, amplifying the original beam.

Phillips and co-workers have now shown that if the quantum phases of the electron waves in these two levels are coupled together, using a light pulse, then light can be emitted from the system without the need for population inversion. Although the conditions needed to observe this effect have been produced in gases, they had never been seen in a solid until now.... nanocrystals amplify light

Nano Image of the Day - Mar 1st 2006

2006-03-01T08:31:00.000-07:00

False color images of a condensate formed from pairs of fermion potassium atoms. Higher areas indicate a greater density of atoms. Images from left to right correspond to the increasing strength of attraction between the atoms that form fermion pairs as the magnetic field strength is varied.

...Fermions have half-integer “spins” (1/2, 3/2, 5/2, etc.), while bosons have integer “spins” (1, 2, 3, etc.). Spins are additive, so that a molecule containing two fermionic atoms is a boson. However, even if two fermions are not bound into one molecule, but merely move together in a correlated fashion, then as a pair they can act like a boson, and undergo condensation. It is this second, more subtle form of condensation that has been observed in the current experiments.

The current work was performed by applying a particular magnetic field at values where individual fermionic atoms cannot bind together to form bosonic molecules. Instead, pairing of fermions is caused by the collective behavior of many atoms, similar to what causes “Cooper pairs” of electrons to form in a superconductor.

Paradoxically, in order to detect that the experiment produced a condensate from paired fermions (and not molecules), the researchers had to first convert the pairs into molecules. A magnetic field at the right strength for molecular bonding was rapidly applied to the fermionic condensate and simultaneously the optical “trap” holding the gas was opened. This magnetic field change can create molecules, but was too fast to create a molecular BEC, as previously shown. Nonetheless, a “picture” of the molecules’ motion showed the characteristic shape of a condensate cloud... source

U.S. Regulators, Experts Launch "Green" Nanotechnology Effort

2006-03-01T08:21:00.000-07:00

Small science will develop products in environmentally safe ways

Washington – U.S. regulators and experts who specialize in nanotechnology (science on the scale of single atoms and molecules) have launched an effort they say will help minimize environmental and health risks that could be associated with such processes and products.

The initiative – a series of meetings on “green” nanotechnology – is led by Barbara Karn, manager of the U.S. Environmental Protection Agency’s (EPA) nanotechnology research program.

"Key nanotechnology companies and researchers,” Karn said during the first GreenNano meeting February 16, “are taking responsibility to ensure that nanotech products are produced in environmentally safe ways.” (See related article.)

Nanotechnology involves imaging, measuring, manipulating and manufacturing things on a scale of 1-100 nanometers. A nanometer is 1 billionth of a meter; a sheet of paper is about 100,000 nanometers thick.

"The GreenNano series,” Karn said, “is designed to explore everything from new nanotechnology products claiming to be better for the environment – because of saved energy, reduced waste, or safer materials used – to smart engineering and business practices.”

The effort also will examine government policies that offer incentives for developing such low-risk practices, and highlight research in green nanotechnology applications, including an eight-session nanotechnology research and environment symposium at the American Chemical Society meeting March 26-30 in Atlanta.

"Nanotechnology holds tremendous potential for pollution prevention and sustainability, especially in the areas of clean water, energy and efficient sensors,” said David Rejeski, director of the Project on Emerging Nanotechnologies at the Woodrow Wilson International Center for Scholars in Washington... green nanotechnology

Nano Image of the Day - Feb 28th 2006

2006-02-28T08:55:00.000-07:00

The complex interaction between light and nanometer structures, like wires, has possibilities as new technology for devices and sensors. NAS researchers are studying light emission from a semiconductor nanowire-typically 10-100 nanometers wide and a few micrometers long-which functions as a laser. Lasers made from arrays of these wires have many potential applications in communications and sensing for NASA. source

Could nanoparticles be designed to become potent antioxidants?

2006-02-28T08:46:00.000-07:00

The responses of cells exposed to nanoparticles have been studied with regard to toxicity, but very little attention has been paid to the possibility that some types of particles can protect cells from various forms of lethal stress.
Research at the Salk Institute for Biological Studies and Columbia University now shows that nanoparticles composed of cerium oxide or yttrium oxide protect nerve cells from oxidative stress and that the neuroprotection is independent of particle size.
As one of the researchers, Professor Dave R. Schubert, head of the Cellular Neurobiology Laboratory at Salk, told Nanowerk: "While there has been a great deal of interest in using nanoparticles as drug delivery vehicles, there has been much less interest in exploring the alternative that they can be engineered to have direct beneficial biological effects."
"Our recent study shows that very simple structures can have properties that may have some clinical relevance and opens the possibility of designing nanoparticles that are more potent antioxidants or have more interesting biological properties." says Schubert.
The increasing use of nanotechnology in consumer products, and industrial and medical applications created a great deal of interest in the potential toxicity of nanomaterials. There have, however, been few studies that examine the biological consequences of the exposure of cells or animals to synthetic nanoparticles. Consequently, the molecular and cellular mechanisms for cytotoxicity of various classes of nanoparticles are not yet fully understood... continue

Nano Image of the Day - Feb 27th 2006

2006-02-27T08:17:00.000-07:00

Single-electron transistor (SET) is a three terminal device, where single electron current between a source and a drain through a nanocrystal is controlled by a gate. The nanocrystals are the tiny light specs.

Nanocrystals: also known as nanoscale semiconductor crystals. "Nanocrystals are aggregates of anywhere from a few hundred to tens of thousands of atoms that combine into a crystalline form of matter known as a "cluster." Typically around ten nanometers in diameter, nanocrystals are larger than molecules but smaller than bulk solids and therefore frequently exhibit physical and chemical properties somewhere in between. Given that a nanocrystal is virtually all surface and no interior, its properties can vary considerably as the crystal grows in size."

"Nanocrystals might be used to make super-strong and long-lasting metal parts. The crystals also might be added to plastics and other metals to make new types of composite structures for everything from cars to electronics." See Discovery could bring widespread uses for 'nanocrystals'. Single atoms caged inside nanocrystals gives you a "quantum confined atom", or QCA, "with potential uses ranging from clear-glass sunglasses to bio-sensors to optical computing and just about anything optical in between." See Nanocrystals Technology Shines New Light on Optics, A Good Look at Nanocrystals, and Researchers Turn Scrap to Strength with Nanocrystals... source

Fluorescent Nanosensor Detects Cell Death

2006-02-27T08:04:00.000-07:00

A team of investigators at Massachusetts General Hospital has developed a nanoparticle that signals when cells are undergoing apoptosis, the kind of cell death triggered by cancer therapies. The new nanoparticles could finally provide oncologists with a rapid assay that could tell them that a given therapy is working. This groundbreaking work was published in the journal Nano Letters.

Too often, oncologists have to wait weeks, or more often months, to learn if the treatment prescribed for a particular patient is working, a predicament that can have dire results. For the patient, receiving a therapy that is not working means unnecessary suffering, both from the tumor continuing to grow and any side effects that accompany the ineffective treatment. Receiving ineffective therapy for longer than needed also delays the start of second-line therapies that might work. Worse still, the failed treatment can trigger genetic defense mechanisms in tumor cells that can render ineffective these second-line therapies using other drugs. This phenomenon is known as cross-resistance.

To develop their apoptosis detector, Ching-Hsuan Tung, Ph.D., Ralph Weissleder, M.D., and Luisa Quinti, Ph.D., honed in on the molecule phosphatidylserine. Phosphatidylserine, or PS, is found normally on the inside of the cell membrane, but this molecule moves to the outside layer of the cell membrane when a cell begins apoptosis. To detect this early indicator of apoptosis, the researchers constructed an artificial small, fluorescent protein that would bind to four different molecules of PS. Test tube experiments showed this construct did indeed bind to PS but not to other membrane components; however, when the investigators tried to use it to detect apoptotic cells, the experiments were a failure. Evidently, their test construct did not bind strongly enough and for a long enough time to apoptotic cells to be detectable... nanosensor detect cell death

Nano Image of the Day - Feb 25th 2006

2006-02-25T08:53:00.000-07:00

At top (A) is the higher resolution image of the word NANO created with a silver superlens. Below that (B) is an image created during a control experiment in which the superlens is replaced by spacer layer. The averaged line width is 60 nanometers in image A with the superlens, and 321 nanometer in image B without the superlens. The scale bar in both images is 2 micrometers. (Image by Cheng Sun, UC Berkeley)

Investing In Nanotechnology

2006-02-25T08:50:00.000-07:00

While increasing amounts of money are being funneled into nanotechnology research and nanotech-related companies, commercial and financial returns from these investments are up to now limited, two recent reports suggest.

According to the independent research firm Cientifica, governments worldwide sank a total of more than $18 billion into nanotechnology between 1997 and 2005. Another $6 billion in combined spending, a 25% increase over that in 2005, is forecast for this year.

“Nanotechnologies will then have received the same level of funding in absolute dollar terms as the entire Apollo program,” the Cientifica report says. In its first eight years, the Apollo space program achieved the first manned flight around the moon, Cientifica notes, while “the entire output of the nanotech program in the layman’s view still consists of only stain-resistant pants.” The economic effect of nanotechnology remains tiny; nanotech-enabled products now generate only a few million dollars in sales.

Cientifica’s analysts interviewed government representatives worldwide as well as individuals ranging from directors to bench scientists at R&D laboratories. Their general conclusion is that nanotechnology is still in its infancy, despite the level of investment. In 2005, Europe, the U.S., and Japan each spent more than $1.2 billion on nanotech R&D, up from just about $100 million each a decade ago... nanotechnology investing

Nano Image of the Day - Feb 24th 2006

2006-02-24T08:53:00.000-07:00

Today's image is of a spider mite sitting on gears made by Sandia Labs. They are in charge of the SAMPLES™(Sandia Agile MEMS Prototyping, Layout Tools, Education and Services) Program which provide customers access to the revolutionary MicroElectroMechanical System (MEMS) using SUMMiT V technology. For more information go to their home page.

Basics of Nanotechnology Presentation from Oxford University

2006-02-24T08:44:00.000-07:00

I found this great flash presentation online about nanotechnology put together by Oxford University Begbroke Science Park. You should definetly check it out.

The University of Oxford is a long-established and universally recognised centre for nanotechnology research. A range of research projects focusing on nanomaterials, particles, fibres, devices and films and arrays, are carried out across the University departments of Materials, Physics, Chemistry, Engineering Science, Physiology, Pathology and Biochemistry. This research is backed by world-class characterisation equipment, located in the Oxford Materials Characterisation Service (OMCS), including an ultra-high resolution electron microscope, a remote scanning electron microscope and a suite of other equipment.

At Begbroke Science Park we encourage research in all these and other multi and interdisciplinary areas, particularly where there is a ‘push-pull’ to providing real world solutions.

The University is also home to two Interdisciplinary Research Collaboration (IRC) centres – Quantum Information Processing (QIP) and Bio-nanotechnology. QIP is a cross-disciplinary team working with industry to harness the latest developments in this field so as to manipulate, store and communicate information. The Bio-nanotechnology IRC investigates naturally occurring biomolecular nanosystems and applies this knowledge to produce artificial electronic and optical devices.

Nano Image of the Day - Feb 23rd 2006

2006-02-23T08:00:00.000-07:00

Pictured on the left is the record-small array of 29.9-nanometer-wide lines and equally sized spaces created by IBM scientists (at its Almaden Research Center in San Jose, California) using a variation of optical lithography. These lines are less than one-third the size of the 90-nanometer features (example at right, same magnification) now in mass production by the microchip industry. They are also smaller than the 32-nanometer size that industry consensus held was the limit for optical lithography techniques. By creating such small features using optical lithography, the IBM researchers have shown the industry a possible route for extending the current manufacturing processes to generate ever-smaller chip circuits. Such an extension may also postpone a high-risk conversion to an extremely expensive alternative. (Note: For comparison, each 29.9 nanometer line is about 3,000 times smaller than a human hair.) via

Methodist Neurosurgeon Makes Quantum Leap on Nano-Level

2006-02-23T07:42:00.000-07:00

A neurosurgeon at the Methodist Neurological Institute (NI) is the first to use an enzyme-driven technique to label nanotubes with quantum dots, giving scientists a better way to see single-walled carbon nanotubes.

The ability to do this labeling allows nanotubes, nanomachines, or other nanoscale optical devices to be used for biomedical research. One practical application might include the precise delivery of medications to specific cancer cells, effectively sparing surrounding healthy cells.

Dr. David Baskin, neurosurgeon at the Methodist NI, and his colleagues published these research findings in the March 2006 issue of BioTechniques.

Dr. Baskin and Vladimir Didenko, PhD used an enzyme to create a permanent bond to attach semi-conductor nanocrystals, or Q-dots, to nanotubes. Because nanotubes absorb light, making them invisible, researchers have tried to find ways to make them visible inside living organisms. The light absorption properties of the nanotubes are bypassed by using the Q-dots... read

Nano Image of the Day - Feb 22nd 2006

2006-02-22T10:20:00.000-07:00

Today's image is computer generated by a new software called Nanorex. The software helps scientists build nanomachines such as this.

This is the MarkIII(k), a planetary gear created by K. Eric Drexler. A planetary gear couples an input shaft via a sun gear to an output shaft through a set of planet gears (attached to the output shaft by a planet carrier). The planet gears roll between the sun gear and a ring gear on the inner surface of a casing. The pair of animations below show a cutaway of the casing, exposing the interaction between internal gears.

Planetary gears are attractive targets for molecular modeling because (with careful choice of planet numbers and sun- and ring-gear symmetries) the overall symmetry of the system virtually guarantees low energy barriers along the desired motion coordinate. They also pack considerable complexity into a small structure.

Planetary gears are common mechanical systems used for speed reduction (= torque multiplication). Macroscale versions are found in automobile transmissions, electric screwdrivers, and Mars landers.

The MarkIII(k) gear updates an early 1990s design by Drexler and Merkle, modified to reduce interactions between the sun gear and the bases of the planet gears. The original version was designed with very small moving parts in order to fit the computational constraints of the time. The planet gears are near the lower limits of diameter for functional gear components, and because of this, the "gear teeth" in this system are better thought of as smooth, low-amplitude corrugations in the gear surfaces.

Fruit of the Nano-Loom

2006-02-22T09:56:00.000-07:00

New textiles tap polymer science to both trap and kill toxins -- all while wicking away sweat.

By exploiting chemistry and nanotechnology, researchers are creating a new generation of clothes that do more than look fashionable and keep the wearer warm. Already, stores are selling pants that resist stains thanks to coatings made of "nanowhiskers," and odor-eating socks that trap microbes using nanoparticles.

Now, scientists are developing clothing for military and medical applications that seem to do it all: block toxins, kill bacteria on the surface, and breathe sufficiently to allow perspiration to escape.

The latest advance, a collaboration between researchers at Cornell University and the University of California, Davis, stitches together porous membranes and bacteria-killing polymer molecules. The results could provide enhanced performance for situations where resistance to liquid or vapor is needed, such as for medical personnel or soldiers exposed to pathogens. The researchers plan to test their new fabric on medical and military staff this year, and to commercialize the fabric by 2008.

"There has been a lot of work in textiles to come up with combinations of materials that give high functional properties," says Kay Obendorf, a textiles chemistry professor at Cornell who specializes in the surface chemistry of fibers. "We need a material that will be a barrier to bacteria while changing its toxicity level."

The latest work had its genesis in 2000, when Gang Sun, a professor of textiles and clothing at the University of California, Davis, invented a method for attaching chlorine-containing polymer molecules, called halamides, to textile fibers. These molecules kill bacteria almost instantly on contact. "Halamides are chemically the same as the disinfectant used in swimming pools," Sun says. "They are safe for contact with the skin, kill bacteria, and absorb odor."... nano fabrics

Nano Image of the Day - Feb 21st 2006

2006-02-21T08:51:00.000-07:00

This scanning electron micrograph shows the new nanofountain-probe dispensing tip.

The miniscule tip on an atomic-force microscope (AFM) helps researchers both "see" and manipulate the nanoscale environment. Now, engineers have created two novel technologies that enable such tips to write features as small as viruses and to withstand abuse with the resilience of diamond. Eventually, they believe, vast arrays of such nanofountain probes could prove useful for crafting such intricate systems as protein arrays or complex semiconductors.

By taking advantage of the same capillary forces that keep fountain pens flowing, researchers from Northwestern University in Evanston, Ill., created a specialized structure that channels inks from a tiny reservoir down to a miniscule AFM tip.

Existing "dip-pen" techniques utilize the same inks, which range from pigments for creating patterns to organic materials for creating sensors, but they suffer from difficulties with maintaining a regular ink supply. The new "nanofountain probe" can paint features as small as 40 nanometers and carries its own ink reservoir... via

Hybrid Nanopeapods Show Potential as Wavelength-controlled Optical Nanoswitches

2006-02-21T08:44:00.000-07:00

A novel micro-reactor approach for fabricating self-organzed, photosensitive gold-peapodded silica nanowires has been developed by a group of researchers in Taiwan. Li-Chyong Chen from the Center for Condensed Matter Sciences at National Taiwan University in Taipei told Nanowerk that "these results manifest the potential of using Au-silica nanopeapods as color-selective optical sensor or nano-switches."

A novel micro-reactor approach for fabricating self-organzed, photosensitive gold-peapodded silica nanowires has been developed by a group of researchers in Taiwan. Li-Chyong Chen from the Center for Condensed Matter Sciences at National Taiwan University in Taipei told Nanowerk that "these results manifest the potential of using Au-silica nanopeapods as color-selective optical sensor or nano-switches."

"Our micro-reactor approach can be applied to prepare a range of hybrid metal-dielectric 0D-1D nanostructures that can be used as functional building blocks for nanoscale sensors, waveguiding devices, and other optoelectronics" says Chen, adding that in the near future, they also plan to replace the noble metals by magnetic metals.

The work with the title "Photosensitive gold-nanoparticle-embedded dielectric nanowires" was published in the Feb. 2006 edition of Nature Materials... read

Photonic nanojets open door to visible-light ultramicroscopy

2006-02-20T09:59:00.000-07:00

A recent paper by researchers at Northwestern University in Illinois provides a physical explanation for the phenomenon wherein the backscattering of light by dielectric particles of sizes between 100 and 1 nm is enhanced by 7–11 orders of magnitude. The findings were published in an article titled "Superenhanced backscattering of light by nanoparticles" in the Jan. 15, 2006 edition of Optics Letters.
Vadim Backman and his group together with co-author Allen Taflove, previously discovered an optical phenomenon called photonic nanojet. These nanojets do not involve evanescent fields and do not require mechanical scanning.

"None of currently available techniques allow non-destructive, quantitative, and cost-effective characterization of individual nanoscale structures with nanometer precision"" Backman told Nanowerk. Instead, nanojets are a local field enhancement generated in the vicinity of a microsphere or microcylinder illuminated by a collimated light beam in the visible wavelength range.
A remarkable property of these photonic nanojets is that they can significantly enhance the backscattering of light by nanometer-scale particles as small as ∼1 nm located within the jets. There appears to be a novel physical mechanism at work which yields this giant backscattering enhancement. "We are all surprised that even the nanojet itself was not calculated until our work, even though Mie solutions to the sphere have been available for literally many decades" Taflove comments.
"This enhancement effect is an intricate physical process where several mechanisms are involved"" says Backman. Furthermore, the intensity and angular distribution of the backscattered signal is extremely sensitive to the size of the nanoparticle, which may enable differentiating particles with accuracy up to ∼1 nm. The unique variation of the nanojet with the size parameter of the nanoparticle was yet another big surprise, according to Taflove... nanojet detecters

Nano Image of the Day

2006-02-19T19:32:00.000-07:00

False-color transmission electron microscope image of self-assembled gold nanochains produced at the University of Chicago. The center-to-center spacing between neighboring chains measures 50 nanometers. Individual gold nanoparticles measure 5 to 10 nanometers and self-assemble inside the polystyrene domains of a thin copolymer film. Polymethylmethacrylate domains of the film, on either side of the chains, do not contain nanoparticles and appear dark. via

New nano-canary in the nanotoxicology coalmine: the body itself

2006-02-19T19:25:00.000-07:00

There is growing consensus among scientists, regulators, politicians, industry and the public that we need to know more about the possible harmful or adverse effects of nanoparticles on human health.

Likewise, most agree that these incredibly small materials can behave quite differently from conventional materials. Nonetheless, neighborhood stores feature products that promise benefits from these near-atomic level materials, from paints and cosmetics to toothpaste and sunscreens. But, could we be putting human health at risk by exposing consumers to potentially toxic materials?

To investigate the damage potential of sub-micron sized particles, S.K. Sundaram and Thomas J. Weber, scientists at the Department of Energy’s Pacific Northwest National Laboratory in Richland, Wash., have harnessed living cells to monitor responses to a variety of toxins. They presented their findings Friday at the American Association for the Advancement of Science annual meeting.

“The process requires that live cells be grown on an infrared transparent substrate giving us an opportunity to closely examine the biological effects in living cells,” said Sundaram. Live cell Fourier transform infrared, FTIR, spectroscopy offers several attractive features for these investigations. These include the potential to detect biologically active nanoparticles without any prior knowledge of cell signaling pathways affected by them or need of a contrast agent to detect the biological response. Thus, live cell FTIR spectroscopy is expected to be a sentinel of exposure to help define nanoparticles that are biologically active, without bias of what that biological activity represents... via

What is Nanotechnology?

2006-02-19T19:15:00.000-07:00

Nanotechnology is the understanding and control of matter at dimensions of roughly 1 to 100 nanometers, where unique phenomena enable novel applications. Encompassing nanoscale science, engineering and technology, nanotechnology involves imaging, measuring, modeling, and manipulating matter at this length scale.

At the nanoscale, the physical, chemical, and biological properties of materials differ in fundamental and valuable ways from the properties of individual atoms and molecules or bulk matter. Nanotechnology R&D is directed toward understanding and creating improved materials, devices, and systems that exploit these new properties.

One area of nanotechnology R&D is medicine. Medical researchers work at
the micro- and nano-scales to develop new drug delivery methods, therapeutics and pharmaceuticals. For a bit of perspective, the diameter of DNA, our genetic material, is in the 2.5 nanometer range, while red blood cells are approximately 2.5 micrometers. Additional information about nanoscale research in medicine is available from the National Institutes of Health.

A nanometer is one-billionth of a meter; a sheet of paper is about 100,000 nanometers thick. See The Scale of Things for a comparative view of the sizes of commonly known items and nanoscale particles... via

Nanotubes break superconducting record

2006-02-17T08:17:00.000-07:00

Physicists in Japan have shown that "entirely end-bonded" multi-walled carbon nanotubes can superconduct at temperatures as high as 12 K, which is 30 times greater than for single-walled carbon nanotubes. The discovery has been made by a team led by Junji Haruyama of Aoyama Gakuin University in Kanagawa. The superconducting nanotubes could be used to study fundamental 1D quantum effects and also find practical applications in molecular quantum computing (Phys. Rev. Lett. 96 057001).

Superconductivity is the complete absence of electrical resistance and is observed in certain materials when they are cooled below a superconducting transition temperature (Tc). Physicists agree that superconductivity relies on getting electrons to overcome their mutual Coulomb repulsion and form "Cooper pairs". In the Bardeen-Cooper-Schrieffer (BCS) theory of low-temperature superconductivity, the electrons are held together because of their interactions with phonons -- lattice vibrations in the material.

However, 1D conductors like carbon nanotubes -- rolled up sheets of graphite just nanometres in diameter -- are not naturally superconducting. One reason for this is the presence of so-called Tomonaga-Luttinger liquid (TLL) states in the material, which cause the electrons to repulse each other and so destroy Cooper pairs.

Now, however, Haruyama and colleagues have designed a system in which there is a superconducting phase that can compete with the TLL phase and even overcome it -- a feat hitherto believed impossible. The system consists of an array of multi-walled carbon nanotubes, each of which consists of a series of concentric nanotube shells. Electrical contacts made of metal are bonded to the tubes so they touch the top of all the shells. Conventional "bulk junction" contacts, in contrast, touch only the outermost shell of a tube and along its length... nanotubes

NSTI Announces Scientific Program for 9th Annual Nanotech 2006

2006-02-15T22:10:00.000-07:00

The Nano Science and Technology Institute (NSTI) recently announced the scientific program and schedule for its Nanotech 2006 Conference and Trade Show, which can be viewed at www.nanotech2006.com. The event is taking place in Boston, Massachusetts at the Hynes Convention Center on May 7 - 11, 2006. Nanotech 2006 is the largest small tech conference in the U.S., and will showcase more than eight hundred technology presentations, government program reviews, an early stage company showcase and expanded vertical industry symposia.

Nanotech 2006 is a unique gathering of the scientific and business community working on the development and commercialization of nano and small-scale technology. More than 200 companies and organizations will exhibit this year and attendance is expected to exceed 3,000. Register early to take advantage of special discounts on registration and hotel accommodations.