First Resources Volume Distribution Chart 20080116

BB are selling and retailers are buying. Trade with care.

Celelstial weekly chart 2005 congestion zone

Testing 2005 congestion support zone 53.5 - 39 cents.

Wait for base formation

Biotech Preview: Genzyme, Biogen, Amgen, Celgene

Despite regulatory hold-ups, reimbursement and labeling issues, some troubled drug sales and a company sale that never happened in 2007, a few big biotech stocks maintain bullish outlooks for fourth-quarter and year-end results, as well as the year ahead.

Genzyme (GENZ - Cramer's Take - Stockpickr), Biogen Idec (BIIB - Cramer's Take - Stockpickr), Amgen (AMGN - Cramer's Take - Stockpickr) and Celgene (CELG - Cramer's Take - Stockpickr) each preannounced fourth-quarter and annual results in conjunction with last week's JPMorgan Healthcare Conference in San Francisco. They guided ahead optimistically. Meanwhile, Genentech (DNA - Cramer's Take - Stockpickr) will share its numbers post-close today and Gilead (GILD - Cramer's Take - Stockpickr) will announce later in January.

Here's a look at what investors saw and expect to see from these companies.

Genentech -- Jan. 14

Genentech kicks off its earnings Monday after market close. Wall Street is looking for adjusted earnings of $720 million, or 68 cents a share, on revenue of $2.9 billion for the fourth quarter. For the year, analysts are seeking $3.1 billion, or $2.92 a share, on revenue of $11.7 billion.
The consensus for fourth-quarter sales includes $603 million from Rituxan, $332 million for Herceptin, $616 million for Avastin, $111 million from Tarceva and $169 million from Lucentis. For the year, analysts are looking for revenue of $11.7 billion, including $2.29 billion from Rituxan, $1.29 billion from Herceptin sales, $2.3 billion from Avastin, $416 million from Tarceva and $817 million from Lucentis.

Genentech in December suffered a negative recommendation from a Food and Drug Administration advisory panel for its Avastin as a treatment for metastatic breast cancer. But the South San Francisco-based company is set to report late-stage data from the Avado trial in the first half of this year and from the Ribbon-1 trial in the second half of the year, which could potentially improve Avastin growth in metastatic breast cancer treatment for 2008, according to Rodman & Renshaw analyst Michael King Jr.

Genentech shares could be influenced by interim, two-year data (three-year disease-free survival data are due in 2009) for Avastin in colorectal cancer sometime during the second half of 2008, according to King. However, he expects the stock will be range-bound until the company releases data from the colorectal cancer and ovarian cancer trials in 2009, in addition to the breast cancer indication.

http://www.thestreet.com/s/biotech-preview-genzyme-biogen-amgen-celgene/newsanalysis/biotech/10398549_2.html

Genentech's mixed bag

Biotech giant beats expectations for earnings but sales only match forecasts

Genentech, the word's largest biotech in terms of market capitalization, reported a healthy increase in sales and earnings for the fourth quarter.

Genentech reported earnings per share of 69 cents, excluding charges, for the fourth quarter, up 13 percent from the same period the previous year. Analysts were predicting earnings of 67 cents per share.

The company reported sales of $2.9 billion, up 9 percent from a year ago and in line with analysts' expectations.

For the full year, Genentech (DNA) reported earnings per share of $2.94, without charges, a 32 percent surge from 2006. Sales came in at $11.7 billion, a 26 percent increase from 2006.

Genentech announced 2008 earnings guidance of $3.30 to $3.45 per share, without charges.
Shiv Kapoor, analyst for Ferris, Baker Watts, said that Genentech "continues to be one of the strongest players in the biotech industry" but "expectations are higher than what they delivered."

Genentech's silver lining

The biotech's top product was Avastin, a treatment for lung and colorectal cancer. Sales jumped 23 percent in the fourth quarter to more than $600 million. The drug's sales nearly reached $3 billion for the year, a 32 percent jump from 2006.

Nonetheless, Avastin is partially responsible for the company's 20 percent slide in stock last year. In December, an advisory panel for the Food and Drug Administration voted 5-4 against approving Avastin as a treatment for breast cancer. The final decision comes out in February.
"The majority expectation is that [Avastin] won't get approved [for breast cancer]," said Jason Kantor, analyst for RBC Capital Markets. "If it did get approved it would have an upside effect."
Ian Clark, executive vice president for Genentech, said, in a conference call with analysts, that "there is definitely room to grow" with Avastin, but "clearly not as much as we would get" with a breast cancer indication.

The company's No. 2 product Rituxan, a treatment for non-Hodgkin's lymphoma and rheumatoid arthritis, rose 10 percent for the year, totaling nearly $2.3 billion. Sales for breast cancer drug Herceptin rose an anemic 4 percent to nearly $1.3 billion for full-year 2007. Sales for Lucentis, a drug to curb age-related vision loss, more than doubled in 2007 to $815 million.
Genentech, based in South San Francisco, Calif., is the No. 2 biotech in terms of annual sales, behind Amgen (AMGN, Fortune 500), based in Thousand Oaks, Calif.

http://money.cnn.com/2008/01/14/news/companies/genentech/index.htm

First Resources 30 mins chart Neckline critical support broken

Neckline support broken and changes its role from support to resistance.

Price rally will probably be capped at neckline resistance.

Further price weakness will probably cause price to move down towards Measured Move Projection Support at $1.15

Head And Shoulders Price Objective

An important, but often overlooked, factor in technical analysis and chart patterns is the calculation of price objectives. This is a measure of where the price is considered to be headed, based on a confirmed pattern. While the price's direction is already known, based on the signal, what needs to be calculated is the projected price movement. This is done so that targets can be set, protective stops can be instituted and the worth of a trade can be evaluated









This is measured based on the height of the chart pattern, which is essentially the distance in price between the peak of the head and the neckline. For example, let's say that in a head-and-shoulders top, the peak of the head is formed at $50 and the neckline was established at $40 - a difference of $10.

The price objective is calculated by subtracting the price at which the pattern breaks the neckline ($40) by the difference between the head and the neckline ($10). Based on this example, the price objective is $30 ($40-$10).

This price objective is not an absolute and is used as a guideline to the attractiveness of a trade. The larger the difference between the objective and the price at the neckline, the more worth the trade has, as it will yield greater returns.

http://www.investopedia.com/university/charts/charts2.asp

Averting a Nano Tragedy

A report released today calls for a systematic approach to risk research in nanotechnologies

Although there is no proof of health risks to humans from nanoparticles, studies do show that materials at this scale behave in some worrying ways, for example, by slipping from the lungs into the bloodstream, and infiltrating other organs, possibly even the brain.
But current efforts at assessing the risk of nanoparticles, including ones already used in sunscreens, face creams, and food supplements, are unfocused and leave gaps in our understanding that "at best...create uncertainties -- and at worst, dangers -- for workers, companies, consumers, investors, and insurers," according to Andrew Maynard, chief science advisor for the Project on Emerging Nanotechnologies at the Woodrow Wilson International Center for Scholars in Washington, DC.

Today, the center released a new report calling for a systematic approach to risk research into nanotechnologies that would include research in a number of areas: the toxicity of substances, how to handle them in the workplace, possible links to specific diseases, and the long-term ways to predict what nanomaterials are likely to be dangerous -- and how to design them to improve their safety.

The report also calls for more funding: a total of $50 million per year for two years, with more to follow.

This could be a hard sell at a time when attention is focused on high fuel prices and the steep bills from the conflict in Iraq.

Might it take a serious problem, then, with people getting hurt, before nanotoxicity research gets the attention it needs?

"I sincerely hope not," Maynard told me over the phone. "My hope is that people see the need and the urgency to invest in this. If it does take an incident to galvanize people, that will be very sad, indeed, because it means we will have lost the opportunity to do something preemptively." -- By Kevin Bullis

http://www.technologyreview.com/blog/editors/17185/

Induced Stem Cells Cure Blood Disease in Mice

The findings demonstrate the cells' promise in treating disease.

Scientists have cured a blood disorder in mice using "induced stem cells"--adult skin cells taken from the animals' tails that were reprogrammed to behave like embryonic stem cells. The findings are the first proof of principle for the potential of these kinds of cells to treat disease.
The cells, known as induced pluripotent cells, have been the source of major excitement among both researchers and the public. They can differentiate into many types of tissue and thus hold promise for cell replacement therapies, but they sidestep the major ethical concern associated with embryonic stem cells: destroying embryos.

In the new experiment, published online today in Science Express, Rudolph Jaenisch and his colleagues at the Whitehead Institute for Biomedical Research, in Cambridge, MA, generated stem cells from the tails of mice with a form of sickle-cell anemia--an inherited blood disorder marked by abnormal blood cells. The researchers then corrected the genetic defect and differentiated the cells into blood-forming stem cells. When injected into mice, the cells developed into healthy blood cells, and the animals' symptoms began to improve.

Jaenisch and his collaborator George Daley did a similar experiment in 2002 using cloned stem cells. But the new findings show that induced cells can perform the same function, providing a potential mechanism for generating personalized stem cells for tissue-replacement therapies without the ethical and technical hurdles associated with human embryonic stem cells.

Scientists have already taken the first step toward translating the findings to humans. Last month, scientists from Wisconsin and Japan garnered major headlines when they announced that they had created induced cells from human skin cells, bringing the research one step closer to potential treatments. (See "Stem Cells without the Embryos.") But researchers still face a major hurdle in using these cells in humans: they need to find a safe way to reprogram the cells, which are currently reprogrammed with viruses.

http://www.technologyreview.com/blog/editors/21973/

KTL Global hourly chart last 2 indecisive directionless dojis

Monitor breakout from trading zone formed by upper resistance 50EMA and 52 cents lower support line .

DNA Deletion Linked to Autism

A specific structural variation on chromosome 16 dramatically boosts the risk of autism, according to a study published today in the New England Journal of Medicine. The finding--one of the most significant to date--permits the development of new diagnostic tests to identify children at risk, and could ultimately point to specific biochemical pathways to target in drug development.

"This is one of the single largest [influences] and most frequent genetic causes for autism identified so far," says Bai-Lin Wu,director of the Genetics Diagnostic Laboratory at Children's Hospital Boston and one of the senior authors on the study.

Autism spectrum disorder--or autism, as it is commonly called--refers to a group of developmental disabilities with wide-ranging language, social, and behavioral symptoms. The disorder is known to have a strong genetic influence, with up to 90 percent of cases thought to have a genetic component. However, because the disorder is linked to a combination of genetic variations, each playing a minor role, identifying specific genetic triggers has been difficult. Now new microarray technologies, which allow scientists to screen a million or more genetic variations in thousands of patients, are enabling the much larger studies needed to pinpoint these triggers.

In the new paper, scientists say that they used microarrays to scour the DNA of more than 2,000 individuals with autism. They found that deletion or duplication of approximately 500 of the same DNA letters on chromosome 16 was strongly linked to autism, accounting for about one percent of cases. "While that doesn't sound like a huge number, the fact that these people carry the identical spontaneous deletion or duplication would be incredibly unlikely to happen by chance," says Mark Daly, a geneticist at Massachusetts General Hospital's (MGH) Center for Human Genetic Research, in Boston, and at the Whitehead Institute, in Cambridge, and one of the study's senior authors.

The results were independently identified by three different groups--at MGH; Children's Hospital Boston; and deCODE Genetics, in Iceland--that are studying three different populations, giving added weight to the work.

The findings build on previous reports that autism is linked to genetic deletions or duplications that arise spontaneously, rather than being passed down through generations. In almost all cases, parents of the affected people did not carry the chromosome 16 variation.

One of the most immediate clinical benefits of the research will be the development of inexpensive diagnostic tests. "Because the variation occurs so frequently, you could directly test for the presence or absence of a duplication or deletion as part of standardized genetic testing for autism," says James Gusella, a neurogeneticist at Harvard Medical School, in Boston, who participated in the research. For example, children who show developmental delays but are too young to undergo clinical autism testing could be screened for this variation, allowing parents and doctors to prescribe intervention for those who test positive. "We will be able to find at-risk children early on so that language and behavior problems can be treated much earlier," says Yiping Shen, director of research and development at Children's Hospital's Genetics Diagnostic Laboratory, who was also involved in the work.

Such testing could also predict if parents with one autistic child are at greater risk of having another; if their child's autism is linked to a spontaneous variation, they are at no greater risk than the general population. Researchers at Children's Hospital, which provides genetic testing to families, are already developing a clinical diagnostic test.

Scientists are also trying to pinpoint the specific gene or genes within this section of DNA that underlie the increased risk. Daly and his collaborators plan to sequence this region of the genome in another group of people with autism, in search of single-letter mutations that might disrupt the function of specific genes. "Genetics provides us with the only opportunity to gain insight into the biological mechanisms that underlie autism," says Daly. "We can look at individual gene discovery as a small first step in the overall path to develop treatments."
Previous studies have identified autism risk genes. However, these studies have focused on people with genetic disorders that often co-occur with autism, such as Fragile-X syndrome, complicating the role those genes play in the disorder. "Up until now, we haven't had the capacity to look at a single gene that is associated with pure autism," says Gusella.

The findings could point to additional spots in the human genome to search for autism risk genes. The variation on chromosome 16 lies within a genetic "hot spot," an area that is predisposed to undergoing structural duplications due to the architecture of the DNA, says Evan Eichler, a geneticist at the University of Washington in Seattle, who wrote an editorial accompanying the paper. "Every time we produce gametes, there's a finite probability of this region to duplicate," he says. In addition, the region has a high concentration of genes that are rapidly evolving in humans. While the significance of that finding is not yet clear, it may explain autism's status as a relatively young disease.

http://www.technologyreview.com/Biotech/20035/page2/

Mitsubishi Unveils Laser TV, 3-D Home Theater

Expected to be available by the end of the year, laser TV promises twice the color of HD.

Last night, at a Consumer Electronics Show event at the Palms Hotel, in Las Vegas, Mitsubishi gave a first look at its forthcoming line of flat-panel, high-definition displays. The company claims that the display "delivers a range of color never seen before in home entertainment." The display, called laser TV, uses laser as the light source, unlike liquid-crystal displays, which use a white backlight, and plasma displays, which use cells of charged gas to illuminate the screen. Mitsubishi representatives didn't supply a lot of details; they said only that the TV will ship to retailers later this year.

At the event, Mitsubishi showed off three 65-inch laser displays, which are currently being manufactured. (Gadget blog Engadget posted nice pictures here.) In addition, the company demonstrated how its laser TV could be used as a 3-D home theater. The company played clips from Beowulf, a football game, and U2's 3-D concert on its laser display. Viewers wore shutter glasses from RealD, a supplier of 3-D technology. Shutters on the lenses switched on and off--imperceptibly--60 times a second, synchronizing to a signal emitted from the display. (See "Hollywood's New 3-D Age.")

The basic premise behind laser TV is not entirely new. (See "Ultra-Colorful TV.") It's essentially a variant of digital light projection (DLP) technology developed at Texas Instruments. DLP chips are in most of the projectors used in business presentations, and they're found in home projection displays. A laser display is built a little differently, however. Instead of projecting light onto a screen from the front, lasers and the DLP chip are in the rear of the display, which allows it to be manufactured thinner than traditional front-projection systems.

The main difference with a laser display, however, is that it uses lasers as the light source. Usually, projection displays shine white light through a color wheel, and then it's projected onto the screen. This approach is inefficient, filtering out much of the original brightness. Laser displays use red, blue, and green lasers to directly deliver the color to the screen. Lasers not only have a brightness and color advantage over filtered white light, but they also have an advantage over light-emitting diode (LED) technology, another up-and-coming display backlight. The color produced by a laser is much more pure than that produced by an LED because the former allows for more-precise color combinations. The net result is an extremely crisp, lifelike image in which white is many times brighter than standard high-definition displays, and black is many times darker.

The laser displays at the Palms looked impressive to me, although Mitsubishi didn't show a side-by-side comparison with other displays. One of the more exciting aspects of these new displays, however, is that they use much less energy than other flat panels do, and they should quickly become less expensive than plasmas since the lasers can be mass-produced in semiconductor facilities.

http://www.technologyreview.com/blog/editors/21996/

Stem Cells from Embryos--without Destroying Them

A single cell removed from developing embryos can be turned into stem cells.

Scientists from Advanced Cell Technology (ACT) caused an uproar in 2006 when they reported that they could generate embryonic stem cells from a human embryo without destroying it, thereby sidestepping the ethical disputes that have mired the field since its inception. While they did create stem cells, and the embryos theoretically could have survived the process, they did not actually survive.

Now scientists at ACT, led by chief scientific officer Robert Lanza, have repeated the feat, developing five embryonic stem-cell lines without destroying the embryos from which they were derived. The researchers plucked a single cell from an early-stage embryo, mimicking a procedure performed during preimplantation genetic diagnosis to determine if the embryo carries harmful genetic mutations. They then transformed that cell into a line of embryonic stem cells by exposing it to chemical factors that mimic the developmental environment. The findings are published today in the journal Cell Stem Cells.

The technique might make new stem-cell lines available to researchers who are supported by government grants. In 2001, President Bush limited federal funding to stem-cell lines already in existence. But many scientists have objected to this limitation, saying that these stem-cell lines are flawed. In a press release issued by his company, Lanza says,

This is a working technology that exists here and now. It could be used to increase the number of stem cell lines available to Federal researchers immediately. We could send these cells out to researchers tomorrow. If the White House approves this new methodology, researchers could effectively double or triple the number of stem cell lines available within a few months. Too many needless deaths continue to occur while this research is being held up. I hope the President will act now and approve these stem cell lines quickly.

Over 80% of the biopsied embryos formed healthy blastocysts, a rate consistent with or higher than previously reported for both biopsied and normal (non-biopsied) embryos. These results are consistent with the fact that thousands of healthy children have been born following the use of PGD testing in IVF clinics worldwide.

However, it's not yet clear if fertility doctors would embrace the technique. When Lanza's team published its initial findings in 2006, doctors said that despite the apparent safety of the biopsy technique used during preimplantation diagnosis, patients undergoing in vitro fertilization would likely be unwilling to subject their embryos to procedures that would not directly benefit their own family, as is the case with preimplantation diagnosis.

The other option would be to apply the technique to the thousands of leftover embryos languishing in frozen storage at fertility clinics. (Parents often generate more embryos than they use.) These embryos could theoretically be biopsied for single cells and then returned to storage. Whether or not that frozen limbo satisfies ethical opponents of embryonic stem-cell research is another matter.

http://www.technologyreview.com/blog/editors/22002/

Unclear if New Stem Cells Eligible for Federal Funding

Only a new president can rescue the field from this funding mess.

It's unclear if a new technique to generate embryonic stem cells without destroying the embryos from which they were derived will be eligible for federal funding, according to news reports last week. Some seem to think the new method satisifies restrictions that prohibit federal funding for research that harms embryos. Others disagree. This latest debate only serves to highlight the need for a new administration and new funding policies to rescue the field from an ethical logjam.
Scientists have jumped through a series of hoops trying to find ways around Bush's 2001 restrictions. (Up until now, derivation of new stem-cell lines required that donor embryos be destroyed.) In the new method,a single cell is removed from an embryo in a procedure similar to that performed by fertility clinics.

This approach, developed by scientists at Advanced Cell Technologies, seems more sensible than previous efforts. (See "Stem Cells from Embryos--without Destroying Them.") For example, last year, scientists created genetically modified embryos that could not develop past a certain point, thereby preventing the destruction of viable embryos. This satisfied some ethicists, but others countered that the method merely generated crippled embryos.

Now an NIH official says that while the method appears to satisfy federal funding rule, the only way to prove it would be to perform an experiment that no one would deem ethically acceptable: implanting embryos used in the experiment into a woman's uterus to see if they can develop normally.

According to the Washington Post,

... the new work shows for the first time that healthy, normal embryonic stem cells can be cultivated directly from embryos without destroying them.

That means the work should be eligible for federal financing under President Bush's six-year-old policy of funding only stem cell research that does not harm embryos, said study leader Robert Lanza, chief scientific officer at Advanced Cell Technology in Worcester.

But that is not likely, said Story Landis, who heads the National Institutes of Health Stem Cell Task Force, which oversees grants for studies on the medically promising cells.

The embryos Lanza used, which were donated for research, appear not to have been damaged, Landis acknowledged. However, she said, "it is impossible to know definitively" that the embryos were not in some subtle way harmed by the experiment. And "no harm" is the basis of the Bush policy, she said.

Landis said the only way to prove that the technique does not harm embryos would be to transfer many of them to women's wombs and see whether the resulting babies were normal. But it would be unethical to do that experiment, she said, so the question cannot be answered.

The only solution to the quagmire? A new president who would support new federal funding guidelines already approved in Congress.

http://www.technologyreview.com/blog/editors/22003/

Yangzijiang approaching all time low support

Monitor All Time Low Support Zone $1.36 - $1.26

Expandable Silicon

A new design for silicon-based chips makes it possible to mechanically stretch them out to cover large areas. These expanded chips, which could be thousands of times the size of the original, could be used to make cheaper solar panels, sensor networks, and flat-screen TVs.

The chips, built by researchers at Stanford University, consist of free-floating islands of silicon surrounded by coils of silicon wire. Each island can be processed to include transistors, sensors, or materials for tiny solar cells. When the corners of the chip are pulled on, the coils around the silicon islands unwind. As they do, the islands, which start out nearly touching each other, spread apart. The end result is a netlike array of silicon devices.

So far the researchers have demonstrated arrays that are 50 times larger than the original chip, but they've been limited by the size of their laboratory equipment. Peter Peumans, the professor of electrical engineering at Stanford who led the work, says that the chips could be made to expand thousands, or even tens of thousands, of times. Peumans's work was presented this week at the International Electron Devices meeting in Washington, DC.

Silicon nets: Using conventional silicon-processing techniques, researchers at Stanford University have built chips that consist of islands of silicon surrounded by silicon coils. The top-left image shows one such silicon island, and the bottom-left image shows the entire chip composed of an array of these islands. When the corners of the chip are pulled, the coils unwind, and the islands spread apart. The finished network is shown at the bottom right. The top-right image shows the coils completely unwound.

The work is "taking the integrated circuit concept that has been so successful in microelectronics and adapting it to large-area applications," says Marc Baldo, a professor of electrical engineering at MIT. The semiconductor industry has excelled at packing more high-performance transistors into a given space, driving down the cost per transistor in the process. But many applications require that transistors and other silicon-based devices be more distributed.

For example, flat-screen TVs need millions of transistors spread out to control each pixel. For LCD TVs, it's been possible to use relatively low-performance transistors, which can be made by depositing amorphous silicon onto large pieces of glass. But the next generation of brighter, more colorful, and more energy-efficient displays, such as organic LED displays, require much higher performance transistors created from higher-grade silicon, which can be extremely expensive, making it impractical to coat an entire display with it. With Peumans's method, it could be possible to use only a small amount of high-grade silicon, thereby cutting costs. What's more, the devices are already wired together. That's an important advantage over some other methods for making large-area electronics since "wiring up large-area electronics can be very expensive," Baldo says.

The ability to use less silicon, and to form orderly arrays of prewired silicon devices, could also be useful for making cheaper solar panels. In conventional solar panels, light is absorbed because the entire panel is coated with high-grade silicon. Now a number of companies are reducing the amount of silicon needed by concentrating sunlight onto smaller silicon chips. For example, one company makes an array of small lenses that focus light onto even smaller silicon solar cells. Peumans says that his method offers a cheaper way of making such solar-cell arrays. Earlier this year, he founded a company called NetCrystal, based in Mountainview, CA, to make such panels, which he expects can be created for a third of the cost of today's panels.

Peumans is also working with Boeing to develop sensor networks for airplanes. The goal is to distribute high-performance, silicon-based sensors between layers of the composite materials that make up the wings and other parts of new aircraft, such as the Boeing 787. These sensors would be used to determine if the materials are cracking or delaminating. The sensors could decrease downtime for inspections and help maintenance crew spot problems earlier, Peumans says.

Peumans's technology is not the first attempt to make large-area electronics. Other approaches, however, tend to produce devices that fall considerably short of the performance of chip-grade, single-crystalline silicon. Some researchers, for example, are developing inexpensive methods that use commercial printing techniques to deposit inorganic or organic semiconductor "inks." But the best inorganic ink-based devices perform about an order of magnitude worse than single-crystalline silicon, whereas organic ink-based transistors are a thousand times worse.

The biggest hurdle in developing Peumans's approach was showing that the coils around the silicon islands would be strong enough not to break as they unwind, but he demonstrated a way to treat the coils to make them stronger. The next step is to demonstrate functioning devices. He has already developed prototype solar cells and is working on partnerships to develop other applications.

http://www.technologyreview.com/Nanotech/19901/page2/

Nanogenerator Fueled by Vibrations

An array of zinc-oxide nanowires that generates current when vibrated with ultrasonic waves could provide a new way to power biological sensors and nanodevices.

Using ultrasonic waves to vibrate an array of zinc-oxide nanowires, researchers at Georgia Tech have made a tiny generator that can produce direct current. By taking advantage of the fact that zinc-oxide nanowires are piezoelectric--they can convert mechanical energy into electricity--and by finding a way to collect electricity from multiple nanowires, the researchers have taken a big step toward a practical nanoscale power generator.

"We can make each and every wire simultaneously and continuously produce electricity," says Zhong Lin Wang, a professor of materials science at Georgia Tech, who led the work. In a Science paper published this week, Wang and his colleagues demonstrate a prototype device, about two millimeters square, that generates around 0.5 nanoamperes of current for more than an hour.

"The technique essentially provides a new method of power generation," says Pulickel Ajayan, a materials engineering professor at Rennselaer Polytechnic Institute. He says that the generator could be coupled with devices that are difficult or inefficient to power using conventional means.

One important application is powering implantable biological sensors. According to Thomas Thundat, who researches nanoscale biological sensors at Oak Ridge National Laboratory, current battery technology limits the use of microelectromechanical sensors that measure cancer biomarkers, blood pH, and glucose. These sensors are getting smaller and smaller, but conventional chemical batteries can't keep up. "[The batteries] are huge and they run out of power...most of the time it's the battery that's big compared to the sensing part," Thundat says. "We have always been looking for very small power sources that don't need refilling." The new nanowire generator looks like a promising answer, he says. It could be implanted in the body, and, driven by muscle contractions, blood flow, or external vibrations transmitted through tissue, it could power the sensors.

The generator could also drive nanodevices. Wang's research group has previously made nanowire pressure sensors that can detect extremely small piconewton forces as well as nanowire gas sensors. (See "A Nano Pressure Sensor.") Instead of an external battery, these devices could run on wind or water flow using the new generator.

A key innovation that has led to the nanowire generator is a new electrode design. The surface of the platinum-coated electrode has a zigzag shape like the teeth of a saw: it has alternating parallel peaks and trenches. This zigzag electrode goes on top of an array of upright zinc-oxide nanowires, and its teeth can push many nanowires at the same time if it moves up and down.

To vibrate the electrode, the researchers package the device, put it in water, and expose it to ultrasonic waves. As the zigzag electrode moves up and down, its peaks push and bend the nanowires, which generate electric current that the electrode collects simultaneously. "The wires can be compressed, can be vibrated left or right--it doesn't matter: all the current adds up in the same direction," Wang says.

This is the first demonstration of a direct current output from nanowires that are driven by mechanical energy, says Charles Lieber, a chemistry professor at Harvard University. The new development is a "key step towards novel, cost-effective, adaptable, and mobile applications of nanogenerators in nanotechnology," he says.

For real-world applications, the current generated by the nanogenerator would need to be higher and more stable. Wang's research group is working on improvements toward that goal. Right now, the nanowires are grown randomly, and the researchers estimate that anywhere between 250 and 1,000 nanowires contribute to the current. This is less than 1 percent of all the wires in the array, Wang says. An important next step is to grow a more regular array of nanowires that are uniform in size and height. Matching the nanowire pattern with the pattern on the electrode would utilize all the nanowires, increasing the current output and making it more stable, he says.

The research team also needs to increase the generator's lifetime. It runs for a little more than an hour right now, and Wang says the researchers are not sure why it dies after that time. As a proof of concept, though, Thundat says that this work is a "major advancement in the power-generation area."

http://www.technologyreview.com/Nanotech/18496/