Nanodot: the original nanotechnology weblog

Earlier this year we reported on the work of Dr. Mauro Ferrari of The University of Texas Health Science Center at Houston on developing nanotech methods of drug delivery (see here and here). A startup company cofounded by Ferrari has now received a $3.5 million grant from the state of Texas to commercialize the nanotech delivery of a drug for cancer treatment. From the University of Texas Health Science Center at Houston, via AAAS EurekAlert “Texas invests record $3.5 million in startup cofounded by UT’s Mauro Ferrari“:

NanoMedical Systems Inc., (NMS), an Austin-based startup cofounded by Mauro Ferrari, Ph.D., of The University of Texas Health Science Center at Houston (UTHSC-Houston), to improve the effectiveness of anti-cancer agents and other medications, has received a record $3.5 million Commercialization Award through the Texas Emerging Technology Fund (ETF).

NMS was one of six companies that received the ETF awards, which were announced by Texas Gov. Rick Perry on Tuesday, Nov. 18.

The grant will help accelerate the completion of engineering and pre-clinical testing for a device, which will allow for a controlled dose of medicine to be released into the bloodstream over many weeks or months. The device will be a safer, more reliable and less costly alternative to a long series of injections or clinical visits. Read the rest of this entry »

Arrays of atomic force probe tips are promising nanotech approaches to denser, faster, cheaper memories (see this post from nine months ago). James Tyrrell of nanotechweb.org (requires free registration) explores the latest progress from the IBM “millipede project” and looks at what yet needs to be done. The researchers have completed a fully functional prototypes system and demonstrated. They have further demonstrated accurate control of tip position at a scanning speed three to four orders of magnitude faster than a typical scanning probe microscope, and the ability to write more than 10⁸ indents at a density of 1 Tb per square inch with a single tip. From “Nanoindenter passes memory test“

Scanning probe-based data storage is back in the news as IBM researchers turn their attention to the thermo-mechanical indentation of polymer media at high patterning densities and fast transfer rates.

Results published in the journal Nanotechnology [abstract] suggest that there could be more mileage in polymer systems than experts first thought and nanotechweb.org interviews Urs Dürig of IBM’s Zurich Research Laboratory, Switzerland, to find out more. Read the rest of this entry »

It has not been tested experimentally yet, but if a proposal to use graphene as a nanotech method to sequence DNA very rapidly and inexpensively pans out, the “wonder material” of nanotechnology could find yet another use. From nanotechweb.org, written by James Dacey (requires free registration) “Graphene could accelerate genomics“:

The “wonder material” graphene could soon be used to analyse DNA at a record-breaking pace. That’s the claim of a physicist in the US who has proposed a new way of reading the sequence of chemical bases in a DNA strand by sending the molecule through a tiny slit in a graphene sheet.

While the technique has yet to be verified experimentally, if successful it could be eligible for the $10 million X Prize for Genomics, which has set the challenge of developing a new rapid and low-cost sequencing technology.

…Henk Postma at California State University Northridge has proposed a way of sequencing an entire DNA strand without the need for blasting or computer processing (arXiv:0810.3035).

The technique involves cutting a very narrow slit or “nanogap” along the length of a piece of graphene — an extremely strong sheet of carbon just one atom thick. A voltage is applied perpendicular to the graphene’s surface, which causes the DNA strand to pass slowly through the slit one base at a time. Read the rest of this entry »

Thanks to KurzweilAI.net and Next Big Future for this news item from the University of Nottingham. British scientists are investigating telescoping carbon nanotubes as a nanotech replacement for current computer memory technologies. From “Miniaturizing memory — taking data storage to the molecular level“:

Current memory technologies fall into three separate groups: dynamic random access memory (DRAM), which is the cheapest method; static random access memory (SRAM), which is the fastest memory — but both DRAM and SRAM require an external power supply to retain data; and flash memory, which is non-volatile — it does not need a power supply to retain data, but has slower read-write cycles than DRAM.

Carbon nanotubes — tubes made from rolled graphite sheets just one carbon atom thick — could provide the answer. If one nanotube sits inside another — slightly larger — one, the inner tube will ‘float’ within the outer, responding to electrostatic, van der Waals and capillary forces. Passing power through the nanotubes allows the inner tube to be pushed in and out of the outer tube. This telescoping action can either connect or disconnect the inner tube to an electrode, creating the ‘zero’ or ‘one’ states required to store information using binary code. When the power source is switched off, van der Waals force —which governs attraction between molecules — keeps the Inner tube in contact with the electrode. This makes the memory storage non-volatile, like Flash memory. Read the rest of this entry »

Recently announced results of a US national survey on nanotech applications for “human enhancement” show widespread public support for enhancements seen as promising an improvement in human health, but little support for other uses. From North Carolina State University, via AAAS EurekAlert “Survey highlights support for nanotech in health fields but disapproval elsewhere“

A landmark national survey on the use of nanotechnology for “human enhancement” shows widespread public support for applications of the new technology related to improving human health. However, the survey also shows broad disapproval for nanotech human enhancement research in areas without health benefits. A team of researchers at North Carolina State University and Arizona State University (ASU) conducted the study, which could influence the direction of future nanotechnology research efforts.

The “Public Awareness of Nanotechnology Study” is the first nationally representative survey to examine public opinion on the use of nanotechnology for human enhancement. The survey found significant support for enhancements that promise to improve human health. For example, 88 percent of participants were in favor of research for a video-to-brain link that would amount to artificial eyesight for the blind. However, there was little support for non-health research endeavors. For example, only 30 percent of participants approved of research into implants that could improve performance of soldiers on the battlefield. Read the rest of this entry »

If you are unable to attend the Convergence08 Unconference this weekend, you can follow some of the developments on FastForward Radio. Christine Peterson and Stephen Gordon pass along this information:

This weekend The Speculist will be presenting not one, but two editions of FastForward Radio, both coming to you live from the Convergence 08 Unconference at the Computer History Museum in Mountain View, California.
Saturday’s show starts at:
8:30 Eastern/7:30 Central/6:30 Mountain/5:30 Pacific.
Sunday’s show starts at:
3:00 Eastern/2:00 Central/1:00 Mountain/Noon Pacific.

Details are available at The Speculist.
—Jim

Paul Marks of New Scientist reports on the release of a report by the UK Royal Commission on Environmental Pollution titled “Novel Materials in the Environment: The case of nanotechnology” (4.6 MB PDF). The report concludes that nanotech products are coming to market without adequate tests for safety based upon the unique properties of the nanomaterials. From Marks’ article “Is nanotechnology a health timebomb?“:

Emerging nanomaterials need to undergo urgent testing to assess their effects on health and the environment, the UK’s Royal Commission on Environmental Pollution said in a report released this week.

It says nanotechnology-based products are hitting the market without being properly assessed for safety - and that’s a risk too far.

…The commission is calling for the European Union to extend its regulatory regime for chemicals (REACH) to properly assess nanomaterials and their unique properties.

In the UK, they want the Department of the Environment, Farming and Rural Affairs (DEFRA) to develop and undertake tests on products that contain nanomaterials, and develop gadgets that detect, for instance, nanomaterials like carbon nanotubes when they become airborne. Read the rest of this entry »

Today we have a nanotech nod to last week’s historic election for US President and an example of the artistic possibilities of nanotechnology, rather than news of scientific or technological advances. The New Scientist blog “Meet president Nanobama” links to a collection of 0.5 millimeter-wide line drawings of President-elect Obama, each made from about 150 million carbon nanotubes. Nanobama is part of John Hart’s nanobliss “gallery of visualizations of small-scale structures of carbon nanotubes and silicon”. The drawings are very definitely not atomically precise. Photolithography is used to pattern nanoparticle catalysts on a glass slide, and then forests of carbon nanotubes grow where the catalysts are present.

—Jim

Nanotech membranes made of nanoporous alumina coated with diamond-like carbon films promise to minimize problems with medical implants. From North Carolina State University, via AAAS EurekAlert “NC State finds new nanomaterial could be breakthrough for implantable medical devices“

A team of researchers led by North Carolina State University has made a breakthrough that could lead to new dialysis devices and a host of other revolutionary medical implants. The researchers have found that the unique properties of a new material can be used to create new devices that can be implanted into the human body — including blood glucose sensors for diabetics and artificial hemo-dialysis membranes that can scrub impurities from the blood.

Researchers have long sought to develop medical devices that could be implanted into patients for a variety of purposes, such as monitoring glucose levels in diabetic patients. However, existing materials present significant problems. Read the rest of this entry »

The publication of a method to mass produce graphene has opened the way to further study of this remarkable nanomaterial, and to its eventual use in a number of nanotech applications. From the University of California - Los Angeles, via AAAS EurekAlert, “Researchers discover method for mass production of nanomaterial graphene“, written by Mike Rodewaldof the UCLA Newsroom:

Graphene is a perfect example of the wonders of nanotechnology, in which common substances are scaled down to an atomic level to uncover new and exciting possibilities.

Graphene is created when graphite — the mother form of all graphitic carbon, which is used to make the pigment that allows pencils to write on paper — is reduced down to a one-atom-thick sheet. Graphene is among the strongest materials known and has an attractive array of benefits. These sheets —single-layer graphene — have potential as electrodes for solar cells, for use in sensors, as the anode electrode material in lithium batteries and as efficient zero-band-gap semiconductors.

Research on graphene sheets has been restricted, though, due to the difficulty of creating single-layer samples for use in experiments. But in a study published online Nov. 9 in the journal Nature Nanotechnology [abstract], researchers from UCLA’s California NanoSystems Institute (CNSI) propose a method which can produce graphene sheets in large quantities. Read the rest of this entry »

A patch consisting of three layers of polymers can be loaded with nanoparticles and attached to living cells to give them nanotech backpacks that could be useful for carrying chemotherapy and imaging agents to tumors, or to align cells in certain patterns for tissue engineering. From “Scientists create tiny backpacks for cells” written by Anne Trafton, MIT News Office (found via PhysOrg.com/a>):

MIT engineers have outfitted cells with tiny “backpacks” that could allow them to deliver chemotherapy agents, diagnose tumors or become building blocks for tissue engineering.

Michael Rubner, director of MIT’s Center for Materials Science and Engineering and senior author of a paper on the work that appeared online in Nano Letters [abstract], said he believes this is the first time anyone has attached such a synthetic patch to a cell.

The polymer backpacks allow researchers to use cells to ferry tiny cargoes and manipulate their movements using magnetic fields. Since each patch covers only a small portion of the cell surface, it does not interfere with the cell’s normal functions or prevent it from interacting with the external environment. Read the rest of this entry »

Re-engineering a simple nanotech device to make it more functional, Chinese scientists have developed an improved DNA tweezers that is able to capture, hold, and release a target molecule in a controlled manner. To do so, they took advantage of an alternative type of DNA base pair that allows a third strand of DNA to bind to a DNA double helix to form triple strand DNA under certain conditions. From a Nanowerk Spotlight, written by Michael Berger “The gripping potential of DNA nanotechnology“:

The exciting potential applications for DNA tweezers include their use in constructing various molecular devices dedicated to repairing a functional unit in a cell, harnessing the delivery of drug molecules to pathogenic cells, or assembling nanoscale devices.

There have been several earlier versions of similar DNA devices that can be operated to have open and close actions but it still has been a challenge to make them behave like real tweezers that can be handled to grasp and transfer an object. A team of Chinese scientists has now demonstrated a very simple design to fabricate a close-to-reality ‘grasp’ and ‘release’ function for a pair of DNA tweezers. Read the rest of this entry »

Robert A. Freitas Jr. brings to our attention a major step on the road to advanced nanotech, published a couple weeks ago in Science (abstract). He writes:

This paper reports purely mechanical-based covalent bond-making and bond-breaking (true mechanosynthesis) involving atom by atom substitution of silicon (Si) atoms for tin (Sn) atoms in an Sn monolayer surface on a Si(111) surface; also demonstrates atomically precise exchange of lead (Pb) and indium (In) on Si(111) surface. This is the first report of a complex pattern being drawn on a 2D surface, literally atom by atom, purely via mechanical forces.

Working on a single atomic layer of tin atoms grown on a single-crystal silicon surface, the Japanese-European collaboration maneuvered an atomic force microscope (AFM) tip precisely (plus or minus 0.01 nm) over a single silicon atom defect in the tin surface, and were able to reversibly exchange a tin atom on the apex of the tip and the silicon atom on the surface. These experiments were done at room temperature and, unlike earlier demonstrations in which a scanning tunneling microscope (STM) tip was used to interchange atoms weakly bond to a metallic surface through use of an electrical bias, this demonstration used mechanical force to interchange strongly bound atoms. Read the rest of this entry »

By nearly eliminating the light lost to solar cells by reflection, a multilayer nanotech coating promises to increase solar cell efficiency. From ScienceDaily “Solar Power Game-changer: ‘Near Perfect’ Absorption Of Sunlight, From All Angles“:

Researchers at Rensselaer Polytechnic Institute have discovered and demonstrated a new method for overcoming two major hurdles facing solar energy. By developing a new antireflective coating that boosts the amount of sunlight captured by solar panels and allows those panels to absorb the entire solar spectrum from nearly any angle, the research team has moved academia and industry closer to realizing high-efficiency, cost-effective solar power.

“To get maximum efficiency when converting solar power into electricity, you want a solar panel that can absorb nearly every single photon of light, regardless of the sun’s position in the sky,” said Shawn-Yu Lin, professor of physics at Rensselaer and a member of the university’s Future Chips Constellation, who led the research project. “Our new antireflective coating makes this possible.” Read the rest of this entry »

A better understanding of how biomineralization converts ordinary minerals to biological mineral structures with extraordinary hardness and fracture resistance may lead to superhard materials for nanotech applications. In the case of sea urchin spicules, the process involves a fractal-like or random walk process by which 40-100 nm particles of amorphous calcium carbonate are converted into a single crystal of calcite with a very unusual geometry. From the University of Wisconsin-Madison, via AAAS EurekAlert “Sea urchin yields a key secret of biomineralization“:

The teeth and bones of mammals, the protective shells of mollusks, and the needle-sharp spines of sea urchins and other marine creatures are made-from-scratch wonders of nature.

Used to crush food, for structural support and for defense, the materials of which shells, teeth and bones are composed are the strongest and most durable in the animal world, and scientists and engineers have long sought to mimic them.

Now, harnessing the process of biomineralization may be closer to reality as an international team of scientists has detailed a key and previously hidden mechanism to transform amorphous calcium carbonate into calcite, the stuff of seashells. The new insight promises to inform the development of new, superhard materials, microelectronics and micromechanical devices. Read the rest of this entry »

You might think that by now the definitions of terms like “nanotechnology” and “nanosystems” would be firmly established. In fact the process of arriving at an international consensus is more difficult than you might expect. Representing Foresight in the effort to define these and other terms is David R. Forrest, Ph.D., President of the Institute for Molecular Manufacturing and a Senior Fellow at the Foresight Nanotech Institute, who serves as Foresight’s representative on the Technical Advisory Group to the American National Standards Institute (ANSI) on the ISO Technical Committee on Nanotechnology (TC/229). From Dr. Forrest’s report on “Foresight’s Standards Work for Molecular Nanosystems“:

The process is glacial: ISO has been at this for three years now and there is still no ratified definition of “Nanotechnology” let alone the myriad of other related terms. Foresight’s continued presence and participation in the ISO process helps to maintain a focus on nanosystems, maintains our stature in the international Nanotechnology community as a leader in education and policy issues, and underscores our commitment to consensus standards as a cornerstone of responsible development of molecular nanotechnology.

—Jim

One of the advantages of nanotech treatments for cancer is that nanoparticles can be large enough to introduce more than one type of therapeutic molecule into the same cancer cell. Another advantage is that nanoparticles can protect and deliver into cells molecules that would never make it into the cancer cell unassisted. Now scientists at Pennsylvania State University have demonstrated that nanoparticles can introduce two very promising, but easily degraded, therapeutic molecules into a laboratory model of human skin, and that together they are much more effective than either is alone is slowing the development of deadly melanoma skin cancer. From the National Cancer Institute’s Alliance for Nanotechnology in Cancer “Nanoparticles Target Multiple Cancer Genes, Shrink Tumors More Effectively“:

Nanoparticles filled with small interfering RNA (siRNA) molecules targeting two genes that trigger melanoma have shown that they can inhibit the development of melanoma, the most dangerous type of skin cancer. The nanoparticles, administered in conjuction with ultrasound irradiation, exerted their effects only on malignant tissue, leaving healthy tissue alone.

“It is a very selective and targeted approach,” said Gavin Robertson, Ph.D., who led the team of researchers from the Penn State College of Medicine. “And unlike most other cancer drugs that inadvertently affect a bunch of proteins, we are able to knock out single genes.” Read the rest of this entry »

Organisms that live in extreme environments may provide building blocks for nanotech applications that need to withstand extreme environments. A virus that infects a microorganism that lives in volcanic springs looks particularly promising. From Norwich BioScience Institutes, via AAAS EurekAlert “Extreme nature helps scientists design nano materials“:

Scientists are using designs in nature from extreme environments to overcome the challenges of producing materials on the nanometre scale. A team from the UK’s John Innes Centre, the Scripps Research Institute in California and the Institut Pasteur in Paris have identified a stable, modifiable virus that could be used as a nanobuilding block.

Viral nanoparticles (VNPs) are ideally sized, can be produced in large quantities, and are very stable and robust. They can self-assemble with very high precision, but are also amenable to modification by chemical means or genetic engineering.

Some applications of VNPs require them to withstand extremely harsh conditions. Uses in electrical systems may expose them to high temperatures, and biomedical uses can involve exposure to highly acidic conditions. VNPs able to remain functional in these conditions are therefore desirable. The team identified viruses from the hot acidic sulphurous springs in Iceland. One of these, SIRV2, was assessed for its suitability for use as a viral nanobuilding block. Read the rest of this entry »

On 5 June 2008, Robert Freitas and Ralph Merkle of the Institute for Molecular Manufacturing (IMM) submitted to IEEE Spectrum the following response to the article “Rupturing the Nanotech Rapture” by Richard A.L. Jones (IEEE Spectrum, June 2008 issue). Their brief letter is reproduced below because Spectrum has chosen to publish only one of the responses it received on this topic.

Several items that Richard Jones mentions are well-known research challenges, not showstoppers. All have been previously identified as such along with many other technical challenges not mentioned by Jones that we’ve been aware of for years. Unfortunately, the article also evidences numerous confusions: (1) The adhesivity of proteins to nanoparticle surfaces can (and has) been engineered; (2) nanorobot gears will reside within sealed housings, safe from exposure to potentially jamming environmental bioparticles; (3) microscale diamond particles are well-documented as biocompatible and chemically inert; (4) unlike biological molecular motors, thermal noise is not essential to the operation of diamondoid molecular motors; (5) most nanodiamond crystals don’t graphitize if properly passivated; (6) theory has long supported the idea that contacting incommensurate surfaces should easily slide and superlubricity has been demonstrated experimentally, potentially allowing dramatic reductions in friction inside properly designed rigid nanomachinery; (7) it is hardly surprising that nanorobots, like most manufactured objects, must be fabricated in a controlled environment that differs from the application environment; (8) there are no obvious physical similarities between a microscale nanorobot navigating inside a human body (a viscous environment where adhesive forces control) and a macroscale rubber clock bouncing inside a clothes dryer (a ballistic environment where inertia and gravitational forces control); and (9) there have been zero years, not 15 years, of “intense research” on diamondoid nanomachinery (as opposed to “nanotechnology”). Such intense research, while clearly valuable, awaits adequate funding — as is now just beginning.

Robert A. Freitas Jr.
Ralph C. Merkle
Institute for Molecular Manufacturing (www.imm.org)

—Jim

To develop nanotech therapies for cancer, it would be useful to be able to follow the distribution of nanoparticles in the patient to see if they are in fact accumulating in the targeted tumor(s). A noninvasive Raman microscope has allowed scientists to track carbon nanotubes injected into living mice. From the National Cancer Institute’s Alliance for Nanotechnology in Cancer “Seeing Nanotubes Targeting Tumors In Vivo“:

Carbon nanotubes have significant potential for delivering both imaging and therapeutic agents to tumors, but there is still a need to better quantify how well these rolled-up sheets of graphite can target tumors. Now, thanks to the development of a microscope capable of measuring Raman spectroscopic signals from living mice, researchers have a noninvasive tool to study where carbon nanotubes travel once they are injected into the blood stream.

Reporting its work in the journal Nano Letters [abstract], a team of investigators led by Sanjiv Gambhir, M.D., Ph.D., principal investigator of the Center for Cancer Nanotechnology Excellence Focused on Therapy Response (CCNE-TR), based at Stanford University, and Hongjie Dai, Ph.D., also a member of the CCNE-TR, described its use of an optimized Raman microscope to track two different sets of carbon nanotubes as they transited through the body of living mice. One of the nanotubes was covered with the tumor-targeting peptide known as RGD; the other set was used without any added functionality. Read the rest of this entry »