Technology Trends

Gecko lizards, which can climb any vertical surface and hang from a ceiling with one toe, have fascinated scientists for a long time. Their foot-hairs have a structure which allow them to strongly adhere to any type and shape of surface. Now, according to this short news release from the National Science Foundation (NSF), researchers from the University of Akron, Ohio, have developed synthetic hairs from multiwalled carbon nanotubes (MWNT) that have adhesion forces 200 times higher than those observed with gecko foot-hairs. This could lead to new dry adhesives used in microelectronics, robotics or space applications. Read more…

Here is the first paragraph of the NSF press release (here is another link if you want to see a picture of a gecko lizard).

Renowned for their ability to walk up walls like miniature Spider-Men–or even to hang from the ceiling by one toe–the colorful lizards of the gecko family owe their wall-crawling prowess to their remarkable footpads. Each five-toed foot is covered with microscopic elastic hairs called setae, which are themselves split at the ends to form a forest of nanoscale fibers known as spatulas. So when a gecko steps on almost anything, these nano-hairs make such extremely close contact with the surface that they form intermolecular bonds, thus holding the foot in place.

So researchers from the University of Akron, helped by a $400,000 grant from the NSF, have developed synthetic hairs from carbon nanotubes that have adhesion forces 200 times higher than those observed with gecko foot-hairs. Here is a link to their own news release.

They built new structures, based on multiwalled carbon nanotubes (MWNT) constructed on polymer surfaces with strong nanometer level adhesion. These structures can be used as dry adhesives similar to or stronger than gecko foot-hairs.

Here is an example of such nanostructures.

The pictures above illustrate the topography and force measurement of multiwalled carbon nanotube brushes on PMMA with a scanning force microscope (SPM). (A) and (B) show real SPM height images taken by tapping mode for vertically and horizontally aligned MWNT, respectively. The bars represent 5 nm and 150 nm, respectively (Credit: University of Akron).

[Note:PMMA, which stands for Poly(methyl methacrylate), is a transparent plastic sold under different names, such as Plexiglas, and is often simply called Acrylic.]

The research paper about this work has been published by Chemical Communications on July 5, 2005 under the title “Synthetic gecko foot-hairs from multiwalled carbon nanotubes” (Issue 30, 2005, Pages 3799 - 3801). Here is a link to the short abstract.

We report a fabrication process for constructing polymer surfaces with multiwalled carbon nanotube hairs, with strong nanometer-level adhesion forces that are 200 times higher than those observed for gecko foot-hairs.

The full paper is available for free for registered users of the Institute of Physics for a duration of one month. Here is a link to this paper (PDF format, 3 pages, 313 KB).

For more information, you also can read a previous entry about a related project, “Spider Legs Lead to Better Post-it Notes.”

These two projects don’t follow the same approach, but they have a similar goal: design improved adhesives that will have critical applications in microelectronics, information technology, robotics, space and other areas.

Sources: National Science Foundation news release, via EurekAlert!, August 15, 2005; and various web sites

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It’s now commonly admitted that our appetite for fossil fuels is having a strong influence on the Earth’s climate — and our future. But what about the concentration of humans in urban areas? Today, 50% of the world’s population is living on about one percent of Earth’s surface. Can this extreme concentration lead to other effects on our climate and weather? In ‘Satellites and the city,’ NASA says that it can help to provide an answer. “Our research suggests that, using satellite data and enhanced models, we will be able to answer several critical questions about how urbanization may impact climate change 10, 25 or even 100 years from now,” says for example a NASA scientist from the Goddard Space Flight Center. But read more…

“More and more people live in cities. This means that cities will grow rapidly over the next several decades. Evidence continues to mount that cities affect the climate,” said J. Marshall Shepherd, Deputy Project Scientist of the Global Precipitation Measurement Mission at NASA’s Goddard Space Flight Center, Greenbelt, Md.

Shepherd and co-author Menglin Jin, a research scientist at the University of Maryland-College Park, suggest that satellite-observed urban information is extremely useful for advancing our ability to simulate urban effects in climate models. They go on further to propose that satellite data is the only feasible way to represent the expanse of global urban surfaces and related changes to the Earth’s surface, vegetation and aerosols.

Below are some images taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite (Credit for images and legends: NASA).

This shows the MODIS land cover classification in southeastern US (near Atlanta). Red color is for Urban Land Build-up (Copied from Jin and Shepherd 2005 with original image source from Michael King).

[And here you can see] the global distribution of fine aerosol optical thickness derived from MODIS measurements on the Terra platform for September 2000. The large values over Southeast Asia, India, Europe, and the United States reflect urban pollution. The large values in the Southern Hemisphere are due to biomass burning.

The two scientists think that urban landscapes are changing the physical processes of land surfaces, such as thermal conductivity, and also adding new characteristics to our land and our atmosphere.

Structures like the Empire State Building in New York City can change the basic wind flow in and around cities that can alter air quality, temperature, cloud distribution and precipitation patterns. It is increasingly evident that such atmospheric changes near cities can be captured by NASA satellites such as Aqua, Landsat, Terra, and the Tropical Rainfall Measurement Mission (TRMM).

This research work has been published by the Bulletin of the American Meteorological Society in May 2005 (Vol. 86, No. 5, pp. 681–689). Strangely, no abstract is available, but here is a link to the full paper named “Inclusion of Urban Landscape in a Climate Model: How Can Satellite Data Help?” (PDF format, 9 pages, 701 KB).

For more recent references about this subject, you also should read “Urban Climate Modeling,” published by NASA on April 27, 2005.

Finally, I want to add one more paper to your reading list. Its title is “Urban aerosols and their variations with clouds and rainfall: A case study for New York and Houston” and here is a link to the full paper (PDF format, 12 pages, 701 KB).

I’ve worked with many meteorologists during my life, but I’m not sure if they’re ready to include these minuscule urban lands into their climate models. Any thoughts?

Sources: NASA/Goddard Space Flight Center news release, via EurekAlert!, July 21, 2005; and various web sites

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A team of chemists from the University of California at Los Angeles (UCLA) has built the world’s first nano valve. This device can trap and release molecules on demand. This mechanical system can control molecules like a water faucet you can open or close at wish. This nano valve has moving parts — switchable rotaxane molecules — attached to a piece of porous glass, with pores only a few nanometers in size. As this nano valve is much smaller than living cells, we can imagine a day when we swallow a nano valve combined with bio-molecules to release drugs inside our bodies. But the full potential of artificial molecular machines will take a long time to materialize. Read more…

“With the nano valve, we can trap and release molecules on demand. We are able to control molecules at the nano scale,” said Jeffrey I. Zink, a UCLA professor of chemistry and biochemistry, a member of the California NanoSystems Institute at UCLA, and a member of the research team.

The image below shows how the nano valve works. And here is a link to a larger version of this diagram.

[On this picture,] “a” shows the structural formula of the rotaxane molecule and the procedure for tethering it to the surface of a tiny piece of glass while “b” shows how the nano valve opens and closes (Credit for image and legend: UCLA).

Now, here are more technical details about this nanofaucet.

This nano valve consists of moving parts — switchable rotaxane molecules that resemble linear motors designed by California NanoSystems Institute director Fraser Stoddart’s team — attached to a tiny piece of glass (porous silica), which measures about 500 nanometers, and which Thoi Nguyen is currently reducing in size. Tiny pores in the glass are only a few nanometers in size.

The valve is uniquely designed so one end attaches to the opening of the hole that will be blocked and unblocked, and the other end has the switchable rotaxanes whose movable component blocks the hole in the down position and leaves it open in the up position. The researchers used chemical energy involving a single electron as the power supply to open and shut the valve, and a luminescent molecule that allows them to tell from emitted light whether a molecule is trapped or has been released.

The research work has been published in the July 19, 2005 of the Proceedings of the National Academy of Sciences as an “open access article” under the name “A reversible molecular valve.” Here is a link to the abstract.

In everyday life, a macroscopic valve is a device with a movable control element that regulates the flow of gases or liquids by blocking and opening passageways. Construction of such a device on the nanoscale level requires (i) suitably proportioned movable control elements, (ii) a method for operating them on demand, and (iii) appropriately sized passageways.

These three conditions can be fulfilled by attaching organic, mechanically interlocked, linear motor molecules that can be operated under chemical, electrical, or optical stimuli to stable inorganic porous frameworks (i.e., by self-assembling organic machinery on top of an inorganic chassis).

In this article, we demonstrate a reversibly operating nanovalve that can be turned on and off by redox chemistry. It traps and releases molecules from a maze of nanoscopic passageways in silica by controlling the operation of redox-activated bistable [2]rotaxane molecules tethered to the openings of nanopores leading out of a nanoscale reservoir.

And if you really want to read more about this molecular valve, here is a link to the full paper (PDF format, 6 pages, 495 KB). But if you’re not a chemist, I doubt you’ll understand the contents.

I’ll leave the last words to Fraser Stoddart.

“Building artificial molecular machines and getting them to operate is where airplanes were a century ago,” Stoddart said. “We have come a long way in the last decade, but we have a very, very long way to go yet to realize the full potential of artificial molecular machines.”

And now, I’m waiting for your own comments: what do you think of these future molecular machines?

Sources: UCLA news release, July 15, 2005; and various web sites

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For many years now, R&D Magazine has given its R&D 100 Awards, also known as “The Oscars of Invention,” to the most innovative ideas of the year. The winners will be announced in the September issue of the magazine, but they already have been notified by — guess what? — fax. This year, the Department of Energy (DOE) labs have won 29 awards, and four of them went to Livermore Nat’l Lab (LLNL). Here I’ve chosen to focus on one of these awards, the bioaerosol mass spectrometer (BAMS). “BAMS has the potential to identify bioagents, such as anthrax, from only a single spore or cell and to clarify the molecular changes that occur in normal and cancerous cells.” But read more…

Below is a diagram showing this bioaerosol mass spectrometry (BAMS) system used to analyze bacterial spores and identify bioagents, such as anthrax, from only a single spore or cell (Credit: Lawrence Livermore National Laboratory).

Here are some more details from the LLNL news release.

Using a laser to peel cells apart and a mass spectrometer to identify the chemicals inside, BAMS can identify airborne pathogens at the single-cell level in about 100 milliseconds. Combining an understanding of laser-particle interactions, the biochemistry of bacteria and mass spectrometry analysis, BAMS is a prototype system that can identify pathogens and differentiate between harmful anthrax spores and benign agents.

BAMS is designed for operation in office buildings that could be targets for a terrorist attack using a biological agent such as anthrax, or at ports of entry such as airports or train stations to monitor for potential epidemic diseases. Future biomedical applications could include rapid detection of respiratory diseases such as tuberculosis and SARS.

As you can easily guess, there are not many reference papers which have been published about this technology. But you can still read two previous articles published by Science & Technology Review, a LLNL publication.

Here are the links to “When Every Second Counts: Pathogen Identification in Less Than a Minute” (September 2003) and “Life at the Nanoscale” (May 2004). The first one gives additional details on the BAMS technique.

The premise of a detect-to-warn system is to allow time to react. “A minute gives people enough time to put on masks, leave the room, hold their breath. The challenge was to actually make a device that could provide answers in less than a minute,” explains Livermore chemist Eric Gard.

The BAMS technique, which Gard and others have been working on for nearly five years, can successfully identify a single airborne particle in about 100 milliseconds. This technique has other applications as well, Gard notes. “In the future, BAMS could also be used as a medical diagnostic to, for instance, track small subpopulations of cancerous cells that deviate from their normal development cycle. As such, BAMS may make far-reaching contributions in the fields of oncology, microbiology, and public health.”

The other article from Science & Technology Review discusses other techniques, but gives a very short summary of the missions of the Livermore’s BioSecurity and Nanosciences Laboratory (BSNL).

One of BSNL’s most important research goals is developing fast, sensitive, and accurate instruments to detect and identify a wide range of pathogens. In the area of airborne pathogen detection, Livermore researchers have worked with colleagues at the University of California (UC) at Davis to develop the bioaerosol mass spectrometer (BAMS). BAMS combines advanced laser desorption and ionization techniques with mass spectrometry, and its sensitivity is two to three times greater than that of other laser ionization techniques. In addition, BAMS’s response time is fast — it can identify a single airborne particle in about 100 milliseconds.

Sources: Lawrence Livermore National Laboratory news release, July 11, 2005; and various web sites

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Imagine someone imitating your signature or changing the dollar amount on a check. How will you detect it? Things have changed since the days when Sherlock Holmes used his legendary magnifying glass. Today, crime investigators specialized in forensic science are using chromatography to identify different inks. But a new approach is described in this article by chemists and forensic scientists from the Federal Bureau of Investigation (FBI) in Quantico, Virginia. This new process, called capillary electrophoresis (CE), which permits to separate the ink into its different pigments, is automated and fast. And results can be stored in a database for future searches. Read more…

Here is the introduction of this article from the FBI.

Evidence from handwritten notes has been a hallmark of crime detection for a long time — but forensic technology has just made the process that much more sophisticated.

That’s good news for investigators of insurance fraud, currency counterfeiting, tax evasion, and insider trading violations.

Then the unknown author points at two articles published in the July 2005 issue of Forensic Science Communications. These articles are generically named “Forensic Analysis of Ballpoint Pen Inks Using Capillary Electrophoresis.”

Here are the links to these two articles, one about black inks, and another one about blue inks.

Why different articles on different colors? Black and blue inks contain dye formulations that have different properties, which requires different methods to separate the dye components.

Here is a general description of this capillary electrophoresis (CE) process.

Capillary electrophoresis (CE) has recently been used for ink analysis. A minute volume of ink (nanoliters) is injected in a narrow silica capillary filled with a buffer solution. Electrical current is then applied to the capillary to separate the ink into its components. Each component passes a photodiode array detector, which records an ultraviolet-visible spectrum. The process is automated, fast, and results can be stored electronically allowing the development of a searchable reference library. This process also detects non-dye additives in the ink that potentially can be used as identifiers.

The CE technique is largely detailed in the two articles mentioned above. But, if you’re not a chemist, I doubt you’ll understand the contents. However, the abstracts are written in plain English. Here is the one about black inks.

Capillary electrophoresis with ultraviolet-visible photodiode array detection (190–600 nm) was studied as an alternative separation and identification tool for forensic ink examination. Two different buffer systems were designed to analyze dye compounds in various black ballpoint pen ink formulations. Results were compared to thin-layer chromatography experiments to evaluate the sensitivity and performance of capillary electrophesis.

Because of the small volume necessary for analysis, the remaining solution could be further processed using current law enforcement procedures for confirmation.

This technique is not limited to ballpoint pen inks and can be applied to food dyes, textile dyes, and ink-jet dyes. Here is an example taken from the article about blue inks.

Experiments have shown that food dyes, textile dyes, and ink-jet dyes can be separated and identified using the anionic and/or cationic dye capillary electrophoresis methods. Acid Yellow 23 (also known as Yellow Food Dye No. 5 or Tartrazine) was identified in a boiled-down sample of Mountain Dew soda (PepsiCo, Chicago, Illinois) using the anionic capillary electrophoresis method (Egan et al. 2005).

Finally, if you want to learn more about how the FBI is putting forensic science at work, you can read its Handbook of Forensic Services (PDF format, 181 pages, 2.70 MB).

Sources: Federal Bureau of Investigation, July 5, 2005; and various FBI web sites

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This week, the cover story of BusinessWeek, “The Power Of Us,” reminds us that “mass collaboration on the Internet is shaking up business.” The long article covers all the new Internet technologies we are using today, from free phone calls using Skype to file-sharing, blogs, wikis and social networking services. As says Howard Rheingold, author of Smart Mobs, a mix of different technologies such as the Web, mobile devices, and the feedback system on eBay “may make some new economic system possible.” In other words, these new Net technologies are creating a new world, where “the economic role of social behavior is increasing.” The whole BusinessWeek article is worth reading, but I want to focus here on InnoCentive, a web-based community matching 80,000 independent scientists (the “solvers”) to relevant R&D challenges facing leading companies (the “seekers”) from around the globe. Read more…

First, here is how some traditional companies are adopting these new tools to face this world of changes.

Traditional companies, from Procter & Gamble Co. to Dow Chemical Co., are beginning to flock to the virtual commons, too. The potential benefits are enormous. If companies can open themselves up to contributions from enthusiastic customers and partners, that should help them create products and services faster, with fewer duds — and at far lower cost, with far less risk. LEGO Group uses the Net to identify and rally its most enthusiastic customers to help it design and market more effectively. Eli Lilly & Co., Hewlett-Packard Co., and others are running “prediction markets” that extract collective wisdom from online crowds, which help gauge whether the government will approve a drug or how well a product will sell.

And here is Rheingold’s vision of this phenomenon.

Howard Rheingold, author of Smart Mobs: The Next Social Revolution, sees a common thread in such disparate innovations as the Internet, mobile devices, and the feedback system on eBay, where buyers and sellers rate each other on each transaction. He thinks they’re the underpinnings of a new economic order. “These are like the stock companies and liability insurance that made capitalism possible,” suggests Rheingold, who’s also helping lead the Cooperation Project, a network of academics and businesses trying to map the new landscape. “They may make some new economic system possible.”

Now, let’s focus on InnoCentive.

Back in 2001, the management of Eli Lilly decided to see if thousands of researchers around the world, and available via the Web, could help its own scientists to find new ideas. And it decided to invest a few million dollars in a young startup company, InnoCentive, short for “Innovation Incentive.” Eli Lilly was soon followed by PG, Dow, DuPont, Boeing and more than 30 other large companies.

Here is how this collaborative technology works. Imagine that you are a company needing to find an answer to a problem that your own teams have not solved. You, as a “seeker,” contact InnoCentive which will post your challenge on the Web, with all the guarantees of anonymity of course. And Innocentive will post the challenge on the Net. Its network of 80,000 independent self-selected “solvers” living in more than 170 countries, will then try to solve this problem.

After a solution is evaluated and accepted, the “solver” will receive an award ranging from $10,000 to $100,000.

If you’re a chemist, here is the list of current chemistry challenges you can solve. For example, if you find “a method to sequester menthol in a flexible sheet” before September 20, 2005, and if your solution is approved, you will earn $50,000.

And if you’re a biologist, you can look at the biology challenges. Imagine you have a good idea to find new “approaches for non-surfactant based laundry detergents.” Submit your proposal before June 24, 2005, and you might have a chance to get $20,000.

Here is a pointer to a list of recent winning solvers.

BusinessWeek confirms that this system is really successful.

More than a third of the two dozen requests P&G has submitted to InnoCentive’s network have yielded solutions, for which the company paid upwards of $5,000 apiece. By using InnoCentive and other ways of reaching independent talent, P&G has boosted the number of new products derived from outside to 35%, from 20% three years ago. As a result, sales per R&D person are ahead some 40%.

So, if you’re an expert in biotechnology or petrochemicals, you might want to join the InnoCentive network. And if you win an award, please drop me a note…

Sources: Robert D. Hof, BusinessWeek Magazine, June 20, 2005 Issue; and various websites

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Making diesel-like liquid from carbohydrates found in plants has been done before by fermenting glucose into ethanol added to gasoline. But this process was inefficient and expensive because the ethanol needed to be separated from water at the end of the fermentation process. Now, a team of chemists at University of Wisconsin-Madison has found a new way to create green diesel from plants which avoids this costly separating phase. Nature adds that this fuel born from carbohydrates could be clean and easy. And this plant-derived fuel can use existing infrastructures for distribution, which is not the case for hydrogen. But don’t rush to your gas station today. Even if this new way to produce green diesel is promising, there are still some challenges to overcome before it becomes commercially available. Read more…

Here is a short description of this new process, provided by the University of Wisconsin-Madison.

University of Wisconsin-Madison College of Engineering researchers have discovered a new way to make a diesel-like liquid fuel from carbohydrates commonly found in plants.

Professor James Dumesic and colleagues [have built] a four-phase catalytic reactor in which corn and other biomass-derived carbohydrates can be converted to sulfur-free liquid alkanes resulting in an ideal additive for diesel transportation fuel.

Nature gives additional details.

A magnesium-based catalyst then knits these molecules together to create the longer carbon chains required for diesel fuel. Adding more pressurized hydrogen, and removing any remaining oxygen atoms with a platinum catalyst, delivers the finished fuel.

Below is a diagram showing the four-phase catalytic processing (Credit: University of Wisconsin-Madison College of Engineering).

This other diagram illustrates the conversion of carbohydrates to a diesel fuel additive (Credit: University of Wisconsin-Madison College of Engineering).

Both of these images come from the headlines news for June 2, 2005 at the University of Wisconsin-Madison College of Engineering.

According to the University, this process is very energy-efficient compared with the production of ethanol.

About 67 percent of the energy required to make ethanol is consumed in fermenting and distilling corn. As a result, ethanol production creates 1.1 units of energy for every unit of energy consumed. In the UW-Madison process, the desired alkanes spontaneously separate from water. No additional heating or distillation is required. The result is the creation of 2.2 units of energy for every unit of energy consumed in energy production.

So will we buy soon such fuels at our gas stations? Here are some answers from Nature.

If all goes according to plan, Dumesic estimates one could grow enough plants in the United States to power a significant percentage of the country’s vehicles.

The next challenge is to work out how to extract the all-important carbohydrates from plant matter. The chemists used a pure carbohydrate supply in their tests, and Dumesic says that plants may have to undergo extensive processing to remove unwanted chemicals.

The research work has been published by Science under the title “Production of Liquid Alkanes by Aqueous-Phase Processing of Biomass-Derived Carbohydrates” (Vol. 308, Issue 5727, Pages 1446-1450, June 3, 2005). Here is a link to the abstract (Free registration required).

Sources: University of Wisconsin-Madison College of Engineering news release, June 2, 2005; Mark Peplow, Nature, June 2, 2005; and various websites

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Many announcements related to nanotechnology have been made last week, so I just want to make a quick summary. A team of chemists have found that buckyballs could have a negative impact on our environment while other researchers used nanotechnology to find tumors before they are visible in conventional MRI. A team at CMU could revolutionize nanoelectronics manufacturing by making ordered nanocarbons while a chemist at New York University thinks that DNA molecules could lead to the smallest computing devices ever built. Cornell University researchers have designed a nanoscale switch linking electronics to photonics and others at the University of Leeds, U.K., have identified antimicrobial nanoparticles for safer food packaging. In the commercial sector, Dimatix is developing nano-printing technologies which could lead to human skin cells, and Accelrys is using molecular modeling and simulation software tools to design potential new materials. Read more…

Please read all the articles or news releases mentioned above to find more information about these new discoveries. Here I just want to focus — briefly — on three of them.

Let’s first look briefly at this new use of nanotechnology to find tumors.

Biomedical engineers have used nanotechnology to find human melanoma tumors in mice while the growths are still invisible to conventional magnetic resonance imaging (MRI).

Earlier detection can potentially increase the effectiveness of treatment. This is especially true with melanoma, which begins as a highly curable disorder, then progresses into an aggressive and deadly disease.

A second benefit of the approach is that the same nanoparticles used to find the tumors could potentially deliver stronger doses of anti-cancer drugs directly to the tumor site with fewer side effects.

Now, here is a short description of the nano-printing technologies developed by Dimatix.

Dimatix currently employs about 50 people in its Santa Clara offices, where it is developing ink-jet printing technologies for a wide range of possible uses. Some futuristic uses of Dimatix’s super-small ink jets could include making semiconductor interconnects, or electronic screen displays so thin and flexible they wrap around a column in a department store.

Dimatix is developing a new generation of print heads that can deposit microscopic droplets of conductive ink, or even droplets of organic materials. They call these nano-particle inks, because they are at the atomic level in size, or smaller than a virus.

In the future, Dimatix expects its printing technologies to be used in the life sciences, where scientists could re-create human cells by layering down DNA substrates.

Finally, it’s time to look at the modeling software tools developed by Accelrys.

Here is the introduction of the article.

As electronics companies find themselves increasingly needing to characterise their materials at nanometre length scales, they are resorting to modelling software packages that until recently were seen as pure research tools.

Cambridge-based molecular modelling and simulation specialist Accelrys says its products, which are built on quantum mechanical descriptions of particular systems, are now being employed for real-world applications, rather than simply in more blue skies research.

Accelrys’ tools are typically applied in the fields of chemistry and fundamental materials science. They are used to address questions of what is happening at the molecular and atomic scales, and below, and enable the modelling of properties such as the electronic behaviour of solids, molecules, interfaces, and molecules on surfaces.

And here is the conclusion from Stephen Warde, European director of marketing for Accelrys.

“What our technology can help you do today is make smarter decisions about materials designs, and understand the materials science issues in more depth… I think it’s fair to say that we’re at the beginning of making those sorts of connections.”

And for more information about the involvement of Accelrys in this field, please read this page about Life Science Modeling.

Sources: American Chemical Society, May 9, 2005; The Whitaker Foundation, May 18, 2005; Carnegie Mellon press release, May 6, 2005; Spencer Reiss, Technology Review, June 2005; Cornell University news release, May 19, 2005; Food Production Daily, May 13, 2005; Therese Poletti, Mercury News, May. 16, 2005; Harry Yeates, ElectronicsWeekly.com, May 19, 2005; and various websites

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I don’t know how many of you are willing to pay $1,000 for a bottle of wine, but I’m sure you would like to know if this 50-year old bottle of Bordeaux is still good before purchasing it. Now, you don’t need to open the bottle to discover it. You can get some high-tech help from a wine scanner using nuclear magnetic resonance (NMR), the same technology used in hospital MRI scans. In “Ultimate wine snob,” the Record, from New Jersey, tells us that you can purchase such a scanner for $50,000. Or you can visit the Crystal Springs Country Club, also in New Jersey, where the first NMR wine scanner has been installed, and ask nicely the owner to scan your bottle. If he accepts, you’ll know if the wine has turned into vinegar and if the seal or the cork of the bottle have been altered. But it will not tell you if the wine is really good and deserves its high price. Read more…

Here is a description of this wine scanner, which only can handle one bottle.

The scanner, built last summer and installed in the fall, looks like a shining chrome water heater with a series of pipes and tubes protruding from the top that connect to computer and electronic gear, as well as tanks of liquid nitrogen and liquid helium.

Inside, a series of coils are super-cooled, a strong magnetic field is created, and the apparatus sends radio frequencies through the glass that can pick up the levels of acetic acid, or vinegar, and acid aldehyde, another compound that can make wine taste foul. A program tweaked to read the spectroscopy analysis runs on a desktop computer hooked up to the device.

This wine scanner is based on wine research done at the Augustine Research Group of chemists at the University of California at Davis.

The Record tells us more about this scanner works.

“It’s basically an MRI for a wine bottle,” says Matt Augustine, the UC-Davis professor who came up with the idea and now acts as operations manager for the [Wine Scanner, Inc.] Morristown start-up.

Scans show distinct peaks for certain elements and compounds in the wine and can detect acetic acid at less than one-tenth the amount that would spoil wine, Augustine says.

Eugene Mulvihill, the New Jersey developer who licensed the technology from UC-Davis and built the first scanner in his Crystal Springs Country Club to check his multimillion-dollar wine cellar, thinks that other people might be interested in this $50,000 wine scanner.

Mulvihill believes auction houses or people with large private collections might want to use his scanner. “You’re not talking an $8 bottle of wine; you’re talking a $1,000 bottle of wine, and you want it to be perfect,” said Mulvihill, who has demonstrated the machine’s findings at tastings in Manhattan.

It’s not yet clear whether a potential market exists for the wine scanner. Mulvihill’s hopeful but says he’s not in a rush.

If you’re interested by the research work behind this wine scanner, a paper has been published by the Journal of Magnetic Resonance (Volume 161, Issue 1, Pages 91-98, March 2003) under the name “Using NMR to study full intact wine bottles.”

Here is a link to the abstract.

A nuclear magnetic resonance (NMR) probe and spectrometer capable of investigating full intact wine bottles is described and used to study a series of Cabernet Sauvignons with high resolution ¹H NMR spectroscopy. Selected examples of full bottle ¹³C NMR spectra are also provided. The application of this full bottle NMR method to the measurement of acetic acid content, the detection of complex sugars, phenols, and trace elements in wine is discussed.

And in the full paper (PDF format, 8 pages, 407 KB), you’ll find a diagram of the experimental setup used to obtain the NMR spectrum of full intact wine bottles.

Finally, if you happen to visit the Crystal Springs Country Club and its Restaurant Latour, you’ll be able to know if one of its 50 vintages of Chateau Latour is still good before pocketing $2,000 or more. Enjoy your dinner!

Sources: Martha McKay, The Record, Hackensack, New Jersey, May 12, 2005; and various websites

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According to the Telegraph, this chilli is so hot, you’d have to drink 250,000 gallons of water just to put out the fire. It’s called the “16 Million Reserve” and is 8,000 times stronger than Tabasco sauce. In fact, it’s not really a sauce, it’s a food additive made of pure capsaicin. Its creator, Blair Lazar, from Extreme Food, describes his experience when he tried it: “It was like having your tongue hit with a hammer. Man, it hurt. My tongue swelled up and it hurt like hell for days.” Another “chilli head” — as are named the lovers of these extra hot sauces — put a single grain into a pan of tomato soup and reported his wife’s words after she tried the soup: “She threatened divorce once she could speak again.” If you’re interested, there will be only 999 bottles for sale, with prices ranging between $159 and $199. Read more…

The article of the Telegraph is very entertaining, so I’ll let you read it. Here are some short excerpts of the history of the product, named “16 Million Reserve”because it’s made of pure capsaicin, which scores at 16 million units on the Scoville scale developed in 1912. (For more details about this scale, read this page at Wikipedia.)

It takes several tons of fresh peppers to produce 1lb of capsaicin for the 16 Million Reserve, and the work takes months. First, moisture is removed from the fresh peppers until a thick tar-like substance remains.

The means by which all further impurities are eliminated, leaving pure capsaicin powder, is a trade secret, but the work takes place in a laboratory where Mr Lazar and his team wear sealed suits with masks to avoid inhaling the dust.

Five years ago Mr Lazar created “2am Reserve” in honour of the hour at which he once closed his bar. It was hotter than any other chilli product on the market, measuring up to 900,000 Scoville units.

He then distilled even stronger chilli extracts, including the scorching “6am Reserve” at 10 million units. Most of the signed and numbered bottles of “16 Million Reserve” will be bought by aficionados known as chilli heads.

But before buying one, read carefully the “Product disclaimer” on the HotSauce.com page mentioned above.

Purchaser of this product hereby acknowledges the intense heat factor of this product and the element of danger if misused. This product is over 100 time hotter than a jalapeno pepper and is a complex blend of fresh peppers and extracts. This product is not a sauce but a food additive and should be used as such only.

And the Telegraph adds the following warning.

Although capsaicin does not actually burn — it fools your brain into thinking that you are in pain by stimulating nerve endings in your mouth — some medical experts believe that it could kill an asthmatic or hospitalise a user who touched his eyes or other sensitive parts of the anatomy.

Well, I guess this is too hot for me. So, for not so hot sauces, you can read a previous entry, “Some Like It Hot, Some Like It Mild,” which contains more explanations about the Scoville scale and a recipe of Habanero Pepper Sauce.

Sources: James Langton, Telegraph.co.uk, May 8, 2005; and various websites

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You certainly know that it’s possible to alter the shape of plastics and polymers by heating them. But now, a team of American and German researchers have found a way to change plastics shape with light, according to this MIT news release. These special polymers can move to new shapes by being exposed to light of specific wavelengths. And they’ll retain this stable new shape until they’re illuminated with another source of light of a different wavelength. This discovery has many potential applications, particularly for medical applications, such as expandable strings keeping blood vessels opened during surgery. Read more…

Here is the introduction of this news release.

Picture a flower that opens when facing the sunlight. In work that mimics that sensitivity to light, an MIT engineer and his German colleagues have created the first plastics that can be deformed and temporarily fixed into shape by light.

Here is how this works.

Key to the work: “molecular switches,” or photosensitive groups that are grafted onto a permanent polymer network. The resulting photosensitive polymer film is then stretched with an external stress and illuminated with ultraviolet light of a certain wavelength. This prompts the molecular switches to crosslink, or bind one to another.

The result? When the light is switched off and the external stress released, the crosslinks remain, maintaining an elongated structure. Exposure to light of another wavelength cleaves the new bonds, allowing the material to spring back to its original shape.

“This is really a new family of materials that can change from one shape to another by having light shined on them,” said Institute Professor Robert Langer of MIT.

And what are some possible applications of these new materials?

Imagine, for example, a “string” of plastic that a doctor could thread into the body through a tiny incision. When activated by light via a fiber-optic probe, that slender string might change into a corkscrew-shaped stent for keeping blood vessels open.

The team is also looking at other medical and industrial applications, such as “paper clips that relax when you don’t need them anymore.”

This research work has been published by Nature in its April 14, 2005 isuue under the title “Light-induced shape-memory polymers.” Here is a link to the abstract and below is the text of this abstract.

Materials are said to show a shape-memory effect if they can be deformed and fixed into a temporary shape, and recover their original, permanent shape only on exposure to an external stimulus. Shape-memory polymers have received increasing attention because of their scientific and technological significance.

In principle, a thermally induced shape-memory effect can be activated by an increase in temperature (also obtained by heating on exposure to an electrical current or light illumination). Several papers have described light-induced changes in the shape of polymers and gels, such as contraction, bending or volume changes. Here we report that polymers containing cinnamic groups can be deformed and fixed into pre-determined shapes — such as (but not exclusively) elongated films and tubes, arches or spirals — by ultraviolet light illumination.

These new shapes are stable for long time periods, even when heated to 50 °C, and they can recover their original shape at ambient temperatures when exposed to ultraviolet light of a different wavelength. The ability of polymers to form different pre-determined temporary shapes and subsequently recover their original shape at ambient temperatures by remote light activation could lead to a variety of potential medical and other applications.

Finally, if the subject interests you, here are two references to previous papers about shape-memory polymers, “Biodegradable, Elastic Shape-Memory Polymers for Potential Biomedical ApplicationsScience” published by Science in May 2002 (free registration for access to the full paper) and “Shape Memory Polymers: Biodegradable Sutures,” published by Materials World in July 2002.

Sources: Elizabeth Thomson, MIT News Office, April 14, 2005; and various websites

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Researchers from the Lawrence Berkeley National Laboratory (LBL) have developed fluorescent and stable nano-probes which can stay inside a cell’s nucleus for hours or even days. According to this LBL news release, this will help biologists to better understand nuclear processes that evolve slowly, such as DNA replication, genomic alterations, and cell cycle control. This research was partially based on previous investigations about quantum dots. Now, the researchers want to tailor their quantum dots, which emit different colors depending on their sizes, to check specific chemical reactions inside nuclei, such as how proteins help repair DNA after irradiation. Read more…

Here is a short description of what the researchers achieved.

“Our work represents the first time a biologist can image long-term phenomena within the nuclei of living cells,” says Fanqing Chen of Berkeley Lab’s Life Sciences Division, who developed the technique with Daniele Gerion of Lawrence Livermore National Laboratory.

Their success lies in specially prepared crystalline semiconductors composed of a few hundred or thousand atoms that emit different colors of light when illuminated by a laser. Because these fluorescent probes are stable and nontoxic, they have the ability to remain in a cell’s nucleus — without harming the cell or fading out — much longer than conventional fluorescent labels.

This could give biologists a ringside seat to nuclear processes that span several hours or days, such as DNA replication, genomic alterations, and cell cycle control. The long-lived probes may also allow researchers to track the effectiveness of disease-fighting drugs that target these processes.

The two researchers closely collaborated with Paul Alivisatos, director of the Materials Sciences Division at LBNL, who’s working on quantum dots for several years now. Here are two links to previous entries about Alivisatos research, “Nano Tetrapods With Tunable ‘Legs’,” and “Nanotech solar cells: Portable Plastic Power.”

So, Chen and Gerion thought it was possible to introduce these quantum dots inside a cell’s nucleus. And they did it.

First, they had to breach the nuclear membrane, which has pores that are only about 20 nanometers wide. To fit through these tiny slits, Chen and Gerion used an especially compact cadmium selenide/zinc sulfide quantum dot coated with silica. Next, they stole a trick from a virus’s playbook to smuggle this nanocrystal past the highly selective membrane that guards the entrance into the nucleus.

Chen and Gerion obtained a portion of this protein and attached it to the quantum dot. The result is a hybrid quantum dot, part biological molecule and part nano-sized semiconductor, that is small enough to slide through the nuclear membrane’s pores and believable enough to slip past the membrane’s barriers.

And what are they working on now?

In the future, they hope to tailor quantum dots to track specific chemical reactions inside nuclei, such as how proteins help repair DNA after irradiation.

They also hope to target other cellular organelles besides the nucleus, such as mitochondria and Golgi bodies. And because quantum dots emit different colors of light based on their size, they can be used to observe the transfer of material between cells.

However, with their current nano-probes, they’re already able to know if “a drug has arrived where it is supposed to, and if it is having the desired impact.”

The research work has been published by Nano Letters on September 9, 2004 (Volume 4, Issue 10, Pages 1827 -1832). Here is a link to the abstract of this paper named “Fluorescent CdSe/ZnS Nanocrystal-Peptide Conjugates for Long-term, Nontoxic Imaging and Nuclear Targeting in Living Cells.”

Sources: Lawrence Berkeley National Laboratory news release, March 18, 2005; and various websites

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In “Lobster colour has quantum cause,” Nature writes that Dutch researchers have found why lobsters change colors when they are cooked. According to Nature, “a lobster’s colour is due to a pigment molecule called astaxanthin, which is attached to a protein called crustacyanin.” The Dutch team, using nuclear magnetic resonance spectroscopy and computer simulations, showed that these astaxanthin molecules, grouped in pairs, are interfering with one another. As a result, it shifts their quantum energy states, altering the wavelength of light they can absorb, thus turning black when cooked. The article doesn’t say how many lobsters the researchers used — and ate — for their experiments, but read more…

First, Nature describes the problem — or the situation.

Chemists know that a lobster’s colour is due to a pigment molecule called astaxanthin, which is attached to a protein called crustacyanin. Astaxanthin is one of the carotenoid pigments responsible for the bright red colours of many animals and plants, including those of oranges, tomatoes and some birds’ feathers.

When a lobster is boiled, its crustacyanin proteins unwind in the heat and the astaxanthin pigment falls off. This ‘free’ astaxanthin is red, just like most other carotenoids, and gives the lobster its freshly-cooked colour. But chemists were mystified as to why live lobsters are blue-black.

Then, Nature describes the Dutch team’s experiments.

The team followed up on the discovery in 2002 that astaxanthin molecules in the crustacyanin proteins are grouped in pairs that cross each other in an X-shape.

This pairing, the researchers’ calculations show, means that the two molecules interfere with one another, like cross-talk between electrical signals in neighbouring wires, and this shifts their quantum energy states. That in turn alters the wavelength of light that they absorb, accounting for most of the blackness.

And here is the conclusion of Francesco Buda of Leiden University in the Netherlands, one of the researchers involved in the project.

“It’s surprising that it took such a long time to solve this problem,” says Buda. But he admits it is only in the past five to ten years that computers have been able to handle the demanding quantum-mechanical calculations involved.

The research work has been published by the Journal of the American Chemical Society under the title “Spectroscopy and Quantum Chemical Modeling Reveal a Predominant Contribution of Excitonic Interactions to the Bathochromic Shift in -Crustacyanin, the Blue Carotenoprotein in the Carapace of the Lobster Homarus gammarus.” Here is a link to the abstract.

And if you want to know more about lobsters, but in plain English, you can read this page at Wikipedia. Or you can check Lobster Facts, written by Alan M. Stewart. It features a picture of a two-color lobster named the Joker, introduced by these words: “The odd thing about this animal is that the cephalothorax is all one [natural] color while the rest of the animal is symmetrically different. Even its mouth parts were normal-colored on the right, and orange on the left.” Is this a real lobster or a PhotoShop joke? You’ll tell me.

Sources: Philip Ball, Nature, February 15, 2005; and various websites

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If you enjoy fishing, I have some good news for you. According to New Scientist in “Light-emitting line reels in the big fish,” American chemists have designed a blend of polymers which changes color if it has been exposed to a previous excessive stress. Before going to fight with a 300-pound marlin, you’ll have to put your fishing line under ultraviolet light. If some parts of the line appear green, it should break soon, so it’s time to switch to a new one before jumping in your boat. But these new fishing lines will not be on sale for a while. First, the changes of colors should be visible under normal light conditions, not only under UV. And real fishing lines are much stronger than the ones fabricated today in the lab. Read more…

Here is the somewhat ‘teasing’ introduction from the New Scientist article.

The big ones might not get away quite so often if an experimental fishing line finds its way to market. The new line changes colour when it has been subjected to too much stress, warning the angler that it is in danger of breaking.

Nylon fishing line is designed to have some stretch. But pull on it too hard — when fighting a large fish, for example, or trying to get loose from a snag — and it can reach the point of “non-recoverable deformation” at which it becomes seriously weakened.

So how did the chemists solve this problem?

The new line has been developed by Christoph Weder, Brent Crenshaw and Jill Kunzelman at Case Western Reserve University in Cleveland, Ohio, US. It contains a type of polymer called a phenylene vinylene oligomer, which fluoresces under ultraviolet light. Crucially, the colour of the light it gives off changes depending on the mechanical stress the molecule has been subjected to.

To make the fishing line, a small amount of the polymer is mixed into standard low-density polyethylene, making up 0.2% of the blend. When the line is not under stress, the polymer molecules are close together and emit reddish-brown visible light when illuminated by UV radiation. But when the material stretches and the polymer molecules pull apart, they fluoresce green. So an angler who feared that a section of line had been under excessive stress could examine it under UV light, and discard it if it glowed green.

As I said above, there are still some hurdles to overcome before you could buy these fishing lines at your local fishing store.

Even more useful would be a polymer whose colour change is visible in normal light, says Crenshaw, who is a graduate student at Case Western’s Functional Polymer Laboratory. He says the team is evaluating possible materials.

The polyethylene fishing line is for demonstration only: it would not be strong enough to stand up to even a 4-kilogram bass, Crenshaw says. But there is no reason the same could not be done with standard nylon fishing line.

For more information, please check the Functional Polymers group site at Case Western Reserve University, and in particular this page about functional polymer blends, where the researchers describe their projects.

Rather than designing and synthesizing new, complex functional macromolecules, minor fractions of a “functional additive” are blended with an “inert matrix polymer” in order to create (often after rather specific processing protocols) a new material with a unique or unusual property matrix.

One key project is focused on the design, synthesis, processing, and characterization of polymer materials with integrated mechanical deformation sensors. Materials with self-assessing capabilities are being investigated, in which photoluminescence is employed as the general sensing principle. The approach is based on the incorporation of small amounts of fluorescent dyes into conventional polymers and relies on the formation of nanoscale aggregates of these sensor molecules in the polymer matrix.

The equilibrium phase behavior of these systems can be influenced via the dye’s chemical structure and the material’s composition. The kinetic aspects of aggregate formation can primarily be manipulated via the processing protocol. Therefore the supramolecular architecture of the targeted polymer/dye nanocomposites can be very well controlled. The approach further exploits that mechanical deformation of these materials leads to shear-induced mixing, which transforms the nanophase-separated systems into molecular mixtures.

As you can see, fishing is not really a major concern for these researchers.

Sources: Kurt Kleiner, New Scientist, February 12, 2005; and various pages at Case Western Reserve University

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Nano-sized particles embedded with bright, light-emitting molecules have enabled researchers to visualize a tumor more than one centimeter below the skin surface using only infrared light. An interdisciplinary team from the Universities of Pennsylvania and Minnesota have imaged tumors within living rats by embedding fluorescent materials into cell-like vesicles called polymersomes, which are composed of two layers of self-assembling copolymers. According to the researchers, this imaging process has the potential to go even deeper. And “it should also be possible to use an emissive polymersome vesicle to transport therapeutics directly to a tumor, enabling us to actually see if chemotherapy is really going to its intended target.” Read more…

“We have shown that the dispersion of thousands of brightly emissive multi-porphyrin fluorophores within the polymersome membrane can be used to optically image tissue structures deep below the skin — with the potential to go even deeper,” said Michael J. Therien, a professor of chemistry at Penn. “It should also be possible to use an emissive polymersome vesicle to transport therapeutics directly to a tumor, enabling us to actually see if chemotherapy is really going to its intended target.”

“These polymers are also larger than phospholipids, so that there is enough space for the fluorophores, which are larger than the average molecule that is found inside cell membranes,” said Daniel Hammer, professor and chair of the Department of Bioengineering at Penn’s School of Engineering and Applied Sciences. “Another feature that makes emissive polymersomes so useful is that they self-assemble. Simply mixing together all component parts gives rise to these functional nanometer-sized, cell-like vesicles.”

Now, what’s next?

According to Therien, there is keen interest in developing new technology that will enable optical imaging of cancer tissue, as such technology will be less costly and more accessible than MRI-based methods and free of the harmful side effects associated with radioactivity. In this imaging system, the fluorophores can also be tuned to respond to different wavelengths of near-infrared light. This sets the stage for using emissive polymersomes to target multiple cancer cell-surface markers in the body simultaneously.

The research work will be published by the Proceedings of the National Academy of Sciences in its online Early Edition. As I’m typing this, the article is not yet online. Be sure to visit the site in a couple of days.

A patent application was filed in February 2004 for this invention named “Polymersomes incorporating highly emissive probes.” You can find technical details on this patent by visiting the United States Patent and Trademark Office and search for it. As the patent is not yet approved, click on the left side of the screen on the “Status & IFW” link. On the next window, enter 10/777,552 as the application number. And in the next window, click on the “Published documents” tab.

Here is a direct link to the patent, but I can’t guarantee it always will work. So use the above method if this direct link leads you to an error. In the mean time, here is the abstract.

The instant invention concerns compositions comprising polymersomes, visible or near infrared emissive agents, and optionally a targeting moiety associated with a surface of the polymersome. The invention also relates to use of these compositions in the treatment of disease and in imaging methodology.

The “Images” section of the patent description contains 16 pages of drawings and pictures, including a black and white version of the photograph shown above.

Sources: University of Pennsylvania news release, via EurekAlert!, and various websites

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