Tag Archives: George Whitesides

Watch out Roomba! Camouflaging soft robots are on the move

Roomba, one of the better known consumer-class robots, is a hard-bodied robot used for vacuum-cleaning (or, hoovering as the Brits say). These days scientists are working on soft-bodied robots modeled on an octopus or a starfish or a squid. A team at Harvard University has added a camouflaging feature to its soft robot.

The Aug. 16, 2012 news release on EurekAlert provides some detail about the inspiration (in a field generally known as biomimicry or biomimetics),

A team of researchers led by George Whitesides, the Woodford L. and Ann A. Flowers University Professor [and well known within the field of nanotechnology], has already broken new engineering ground with the development of soft, silicone-based robots inspired by creatures like starfish and squid.

Now, they’re working to give those robots the ability to disguise themselves.

“When we began working on soft robots, we were inspired by soft organisms, including octopi and squid,” Morin said [Stephen Morin, a Post-Doctoral Fellow and first author for the paper]. “One of the fascinating characteristics of these animals is their ability to control their appearance, and that inspired us to take this idea further and explore dynamic coloration. I think the important thing we’ve shown in this paper is that even when using simple systems – in this case we have simple, open-ended micro-channels – you can achieve a great deal in terms of your ability to camouflage an object, or to display where an object is.”

“One of the most interesting questions in science is ‘Why do animals have the shape, and color, and capabilities that they do?'” said Whitesides. “Evolution might lead to a particular form, but why? One function of our work on robotics is to give us, and others interested in this kind of question, systems that we can use to test ideas. Here the question might be: ‘How does a small crawling organism most efficiently disguise (or advertise) itself in leaves?’ These robots are test-beds for ideas about form and color and movement.”

Peter Reuell’s Aug. 16, 2012 article for Harvard Science, which originated the news release, describes some of the technology and capabilities,

Just as with the soft robots, the “color layers” used in the camouflage start as molds created using 3-D printers. Silicone is then poured into the molds to create micro-channels, which are topped with another layer of silicone. The layers can be created as a separate sheet that sits atop the soft robots, or incorporated directly into their structure. Once created, researchers can pump colored liquids into the channels, causing the robot to mimic the colors and patterns of its environment.

The system’s camouflage capabilities aren’t limited to visible colors though.

By pumping heated or cooled liquids into the channels, researchers can camouflage the robots thermally (infrared color). Other tests described in the Science [journal]  paper used fluorescent liquids that allowed the color layers to literally glow in the dark.

“There is an enormous amount of spectral control we can exert with this system,” Morin said. “We can design color layers with multiple channels, which can be activated independently. We’ve only begun to scratch the surface, I think, of what’s possible.”

The uses for the color-layer technology, however, don’t end at camouflage.

Just as animals use color change to communicate, Morin envisions robots using the system as a way to signal their position, both to other robots, and to the public. As an example, he cited the possible use of the soft machines during search and rescue operations following a disaster. In dimly lit conditions, he said, a robot that stands out from its surroundings (or even glows in the dark) could be useful in leading rescue crews trying to locate survivors.

So,  if the scientists are pumping the colour into the soft robot, it’s still a long way from nature’s design where the creature produces its own colourants and controls its own camouflage in response to environmental factors.

Interestingly, there’s no mention of military applications for this camouflaging robot.

Magical nanobots at University of Florida kill (almost) 100% of Hepatitis C virus—in the lab

I’ve always preferred the term nanobots but the folks at the University of Florida are calling them nanorobots, from the July 16, 2012 news item on phys.org,

University of Florida researchers have moved a step closer to treating diseases on a cellular level by creating a tiny particle that can be programmed to shut down the genetic production line that cranks out disease-related proteins.

In laboratory tests, these newly created “nanorobots” all but eradicated hepatitis C virus infection. The programmable nature of the particle makes it potentially useful against diseases such as cancer and other viral infections.

The research effort, led by Y. Charles Cao, a UF associate professor of chemistry, and Dr. Chen Liu, a professor of pathology and endowed chair in gastrointestinal and liver research in the UF College of Medicine, is described online this week in the Proceedings of the National Academy of Sciences.

The news item originated with a July 16, 2012 news release from the University of Florida which goes on to explain how the researchers succeeded,

The Holy Grail of nanotherapy is an agent so exquisitely selective that it enters only diseased cells, targets only the specified disease process within those cells and leaves healthy cells unharmed.

To demonstrate how this can work, Cao and colleagues, with funding from the National Institutes of Health, the Office of Naval Research and the UF [University of Florida] Research Opportunity Seed Fund, created and tested a particle that targets hepatitis C virus in the liver and prevents the virus from making copies of itself.

Hepatitis C infection causes liver inflammation, which can eventually lead to scarring and cirrhosis. The disease is transmitted via contact with infected blood, most commonly through injection drug use, needlestick injuries in medical settings, and birth to an infected mother. More than 3 million people in the United States are infected and about 17,000 new cases are diagnosed each year, according to the Centers for Disease Control and Prevention. Patients can go many years without symptoms, which can include nausea, fatigue and abdominal discomfort.

Current hepatitis C treatments involve the use of drugs that attack the replication machinery of the virus. But the therapies are only partially effective, on average helping less than 50 percent of patients, according to studies published in The New England Journal of Medicine and other journals. Side effects vary widely from one medication to another, and can include flu-like symptoms, anemia and anxiety.

Cao and colleagues, including graduate student Soon Hye Yang and postdoctoral associates Zhongliang Wang, Hongyan Liu and Tie Wang, wanted to improve on the concept of interfering with the viral genetic material in a way that boosted therapy effectiveness and reduced side effects.

The particle they created can be tailored to match the genetic material of the desired target of attack, and to sneak into cells unnoticed by the body’s innate defense mechanisms.

Recognition of genetic material from potentially harmful sources is the basis of important treatments for a number of diseases, including cancer, that are linked to the production of detrimental proteins. It also has potential for use in detecting and destroying viruses used as bioweapons.

The new virus-destroyer, called a nanozyme, has a backbone of tiny gold particles and a surface with two main biological components. The first biological portion is a type of protein called an enzyme that can destroy the genetic recipe-carrier, called mRNA, for making the disease-related protein in question. The other component is a large molecule called a DNA oligonucleotide that recognizes the genetic material of the target to be destroyed and instructs its neighbor, the enzyme, to carry out the deed. By itself, the enzyme does not selectively attack hepatitis C, but the combo does the trick.

“They completely change their properties,” Cao said.

In laboratory tests, the treatment led to almost a 100 percent decrease in hepatitis C virus levels. In addition, it did not trigger the body’s defense mechanism, and that reduced the chance of side effects. Still, additional testing is needed to determine the safety of the approach. [emphases mine]

This treatment builds on some previous research,

The UF nanoparticle design takes inspiration from the Nobel prize-winning discovery of a process in the body in which one part of a two-component complex destroys the genetic instructions for manufacturing protein, and the other part serves to hold off the body’s immune system attacks. This complex controls many naturally occurring processes in the body, so drugs that imitate it have the potential to hijack the production of proteins needed for normal function. The UF-developed therapy tricks the body into accepting it as part of the normal processes, but does not interfere with those processes.

Since there’s no mention of human clinical trials, I’m guessing that we are at least 10 years from seeing this therapeutic agent on the market.

After drafting this post yesterday (July 17, 2012) and while waiting to post it today, I found Dexter Johnson’s July 17 2012 posting where he makes some important points about this research (Note: I have removed a link),

Of course, this is a long way from becoming a treatment anytime soon. A major caveat is that the use of nanotreatments for the targeting and destroying of abnormal cells like cancer cells is always problematic since those cells are “still us” as George Whitesides noted some time back.  It’s always a bit of a tricky business to make sure that nanoparticles are targeting those biological processes within us that we want stopped and not the ones we want to keep.

Dexter goes on to comment about using the terms ‘nanobots’ or ‘nano robots’; he’s less sanguine about it than I am.

NISE Net’s Youtube channel

Dexter Johnson at his Nanoclast blog noted in an October 13, 2010 posting that NISE Net (Nanoscale Informal Science Education Network) has placed a number of nanotechnology-related videos on its own Youtube channel. From the Nanoclast posting,

I haven’t really looked at a wide variety of videos that NISE has collected, but the ones that come from a DVD NISE Network produced called “Talking Nano” contains some real gems. In particular, I enjoyed a seminar George Whitesides gave educators and journalists back in 2007 at the Museum of Science in Boston on what they should know and consider important when relating the subject of nanotechnology either to their students or their audience.

Whitesides, of course, is a renowned scientist at Harvard University, and someone who I’ve come to appreciate for his unique perspectives on how nanotechnology will develop.

Dexter features part 1 of the Whitesides interview which he recommends. I haven’t had time to check the video out yet, although based on the pleasure of seeing some of Whitesides’ collaborative work with Felice Frankel in book form, I too would recommend it.

Telecommunications through chemistry?

This isn’t intended to replace the use of electronics to transmit information but the work that George Whitesides and colleagues at Harvard University have just published (in Angewandte Chemie) is stunning to me.  From the news item on physorg.com,

We currently transmit information electronically; in the future we will most likely use photons. However, these are not the only alternatives. Information can also be transmitted by means of chemical reactions. George M. Whitesides and his colleagues at Harvard University in Cambridge have now developed a concept that allows transmission of alphanumeric information in the form of light pulses with no electricity: the “infofuse”.

Transmitting information by a chemical reaction? This is how the researchers approached the problem initially,

The strips were covered with patterns of dots made of salts of the elements lithium, rubidium, and cesium. When the strip is ignited, the flame travels forward and reaches the dots one after the other. The heat causes the elements to emit light at characteristic wavelengths. The dots may contain combinations of three different salts, resulting in seven possible combinations. A combination of two dots thus allows for 7×7 = 49 different signals.

The researchers have since tweaked the process to address some of the issues such as flames extinguishing themselves too quickly, etc. because,

“We hope that it will be possible to develop a light, portable, non-electric system of information transmission that can be integrated into modern information technology,” says Whitesides. “For example, it could be used to gather and transmit environmental data or to send messages by emergency services.”

Whitesides has been mentioned on this blog before, notably in regards to an article by Robert Fulford (in Canada’s National Post) about a nanotechnology book he  co-authored with Felice Frankel. Interestingly his recently published article on the ‘infofuse’ was funded by the American Cancer Society and supported the US Dept. of Defense’s DARPA (Defense Advanced Research Projects Agency) . A rather unusual pairing, non?

Bacterial nanobots build a pyramid; solar cell breakthrough in Quebec; global nano regulatory framework conference at Northeastern University; Robert Fulford talks about the poetry of nanotechnology

Just when I was thinking that the Canadian nanotechnology scene was slowing down there’s this: A research team at the École Polytechnique de Montréal (Québec) has announced that they’ve trained bacteria to build structures shaped like pyramids. From the news item on Nanowerk,

Faster than lion tamers… More powerful than snake charmers… Make way for the bacteria trainers! Professor Sylvain Martel and his team at the École Polytechnique de Montréal NanoRobotics Laboratory have achieved a new world first: “training” living bacteria to build a nanopyramid.

These miniature construction workers are magnetotactic bacteria (MTB): they have their own internal compasses, allowing them to be pulled by magnetic fields. MTB possess flagella bundles enabling each individual to generate a thrust force of approximately 4 picoNewtons. Professor Martel’s team has succeeded in directing the motion of a group of such bacteria using computer-controlled magnetic fields. In an experiment conducted by Polytechnique researchers, the bacteria transported several epoxy nanobricks and assembled them into a step-pyramid structure, completing the task in just 15 minutes. The researchers have also managed to pilot a group of bacteria through the bloodstream of a rat using the same control apparatus.

Nanowerk also features a video of the magnetotactic bacteria at work.

Solar cell breakthrough?

More Canadian nano from Québec: a researcher (Professor Benoît Marsan) and his team at the Université du Québec à Montréal (UQAM) have provided solutions to two problems which have been inhibiting the development of the very promising Graetzel solar cell that was developed in the 1990s in Switzerland. From the news item on Nanowerk a description of the problems,

Most of the materials used to make this cell are low-cost, easy to manufacture and flexible, allowing them to be integrated into a wide variety of objects and materials. In theory, the Graetzel solar cell has tremendous possibilities. Unfortunately, despite the excellence of the concept, this type of cell has two major problems that have prevented its large-scale commercialisation:

– The electrolyte is: a) extremely corrosive, resulting in a lack of durability; b) densely coloured, preventing the efficient passage of light; and c) limits the device photovoltage to 0.7 volts.

– The cathode is covered with platinum, a material that is expensive, non-transparent and rare. Despite numerous attempts, until Professor Marsan’s recent contribution, no one had been able to find a satisfactory solution to these problem

Now a description of the solutions,

– For the electrolyte, entirely new molecules have been created in the laboratory whose concentration has been increased through the contribution of Professor Livain Breau, also of the Chemistry Department. The resulting liquid or gel is transparent and non-corrosive and can increase the photovoltage, thus improving the cell’s output and stability.

– For the cathode, the platinum can be replaced by cobalt sulphide, which is far less expensive. It is also more efficient, more stable and easier to produce in the laboratory.

More details about the work and publication of the study are at Nanowerk.

Northeastern University and nano regulatory frameworks

According to a news item on Azonano, Northeastern University’s (Boston, MA) School of Law will be hosting a two-day conference on international regulatory frameworks for nanotechnology.

Leading international experts on the global regulation of nanotechnologies, including scientists, lawyers, ethicists and officials from governments, industry stakeholders, and NGOs will join in a two-day conference May 7-8, 2010 at Northeastern University’s School of Law.

The conference will identify best practices that address the needs of industries, the public and regulators. Speakers include representatives from the U.S. Environmental Protection Agency, the Brazil Ministry of Science and Technology, the Korean government, the International Conference of Chemicals Management and National Science Foundation-funded university-industry collaborations.

I checked out the law school’s conference website and noted a pretty good range of speakers from Asia, Europe, and North and South America. It can’t have been easy pulling such a diverse group together. Unfortunately, I didn’t recognize names other than two Canadian ones: Dr. Mark Saner and Pat Roy Mooney.

Saner who’s from Carleton University (Ottawa, Ontario) co-wrote a paper cited by Peter Julian (Canadian Member of Parliament) as one of the materials he used for reference when drawing up his recently tabled bill on nanotechnology regulation. (You can see Julian’s list here.) Saner, when he worked with the Council of Canadian Academies, was charged with drawing together the expert panel that wrote the council’s paper on nanotechnology. That panel put together a report (Small is Different: A Science Perspective on the Regulatory Challenges of the Nanoscale) that does a thoughtful job of discussing nanotechnology, regulations, the precautionary principle, etc. and which you can find here. (As I recall I don’t agree with everything as written in the report but it is, as I noted, thoughtful.)

As for Pat Roy Mooney, he’s the executive director for the ETC Group which is a very well-known (to many scientists and businesses in the technology sectors) civil society group. There’s an Oct. 2009 interview with Mooney here where he discusses (in English) nanotechnology during a festival in Austria.

Robert Fulford and nanotechnology

Canadian journalist and author, Robert Fulford just penned an essay/article about nanotechnology for the National Post. From the article,

Fresh bulletins regularly bring news of startling developments in this era’s most surprising and perhaps most poetic form of science, nanotechnology, the study of the unthinkably small.

It’s a pleasure to read as a literary piece. Fulford mostly concerns himself with visions of what nanotechnology could accomplish and with a book (No small matter) by Felice Frankel and George Whitesides which I first saw mentioned by Andrew Maynard on his 2020 Science blog here.

Responsible science communication and magic bullets; lego and pasta analogies; sing about physics

Cancer’s ‘magic bullet],  a term which has been around for decades, is falling into disuse and deservedly. So it’s disturbing to see it used by someone in McGill University’s (Montreal, Canada) communications department for a recent breakthrough by their researchers.

The reason ‘magic bullet for cancer’ has been falling into is disuse because it does not function well as a metaphor with what we now know about biology. (The term itself dates from the 19th century and chemist, Paul Erlich.) It continues to exist because it’s an easy (and lazy) way to get attention and headlines. Unfortunately, hyperbolic writing of this type obscures the extraordinary and exciting work that researchers are accomplishing. From the news release on the McGill website (also available on Nanowerk here),

A team of McGill Chemistry Department researchers led by Dr. Hanadi Sleiman has achieved a major breakthrough in the development of nanotubes – tiny “magic bullets” that could one day deliver drugs to specific diseased cells.

The lead researcher seems less inclined to irresponsible hyperbole,

One of the possible future applications for this discovery is cancer treatment. However, Sleiman cautions, “we are still far from being able to treat diseases using this technology; this is only a step in that direction. Researchers need to learn how to take these DNA nanostructures, such as the nanotubes here, and bring them back to biology to solve problems in nanomedicine, from drug delivery, to tissue engineering to sensors,” she said.

You’ll notice that the researcher says these ‘DNA nanotubes’ have to be brought “back to biology.” This comment brought to mind a recent post on 2020 Science (Andrew Maynard’s blog) about noted chemist and nanoscientist’s, George Whitesides, concerns/doubts about the direction for cancer and nanotechnology research. From Andrew’s post,

Cancer treatment has been a poster-child for nanotechnology for almost as long as I’ve been involved with the field. As far back as in 1999, a brochure on nanotechnology published by the US government described future “synthetic anti-body-like nanoscale drugs or devices that might seek out and destroy malignant cells wherever they might be in the body.”

So I was somewhat surprised to see the eminent chemist and nano-scientist George Whitesides questioning how much progress we’ve made in developing nanotechnology-based cancer treatments, in an article published in the Columbia Chronicle.

Whitesides comments are quite illuminating (from the article, Microscopic particles have huge possibilites [sic], by Ivana Susic,

George Whitesides, professor of chemistry and chemical biology at Harvard University, said that while the technology sounds impressive, he thinks the focus should be on using nanoparticles in imaging and diagnosing, not treatment.

The problem lies in being able to deliver the treatment to the right cells, and Whitesides said this has proven difficult.

“Cancer cells are abnormal cells, but they’re still us,” he said. [emphasis is mine]

The nanoparticles sent in to destroy the cancer cells may also destroy unaffected cells, because they can sometimes have cancer markers even if they’re healthy. Tumors have also been known to be “genetically flexible” and mutate around several different therapies, Whitesides explained. This keeps them from getting recognized by the therapeutic drugs.

The other problem with targeting cancer cells is the likelihood that only large tumors will be targeted, missing smaller clumps of developing tumors.

“We need something that finds isolated [cancer] clumps that’s somewhere else in the tissue … it’s not a tumor, it’s a whole bunch of tumors,” Whitesides said.

The upside to the treatment possibilities is that they buy the patient time, he said, which is very important to many cancer patients.

“It’s easy to say that one is going to have a particle that’s going to recognize the tumor once it gets there and will do something that triggers the death of the cell, it’s just that we don’t know how to do either one of these parts,” he said.

There is no simple solution. The more scientists learn about biology the more complicated it becomes, not less. [emphasis is mine] Whitesides said one effective way to deal with cancer is to reduce the risk of getting it by reducing the environmental factors that lead to cancer.

It’s a biology problem, not a particle problem,” he said. [emphasis is mine]

If you are interested , do read Andrew’s post and the comments that follow as well as the article that includes Whitesides’ comments and quotes from Andrew in his guise as Chief Science Advisor for the Project on Emerging Nanotechnologies.

All of this discussion follows on yesterday’s (Mar.17.10) post about how confusing inaccurate science reporting can be.

Moving onwards to two analogies, lego and pasta. Researchers at the University of Glasgow have ‘built’ inorganic (not carbon-based) molecular structures which could potentionally be used as more energy efficient and environmentally friendly catalysts for industrial purposes. From the news item on Nanowerk,

Researchers within the Department of Chemistry created hollow cube-based frameworks from polyoxometalates (POMs) – complex compounds made from metal and oxygen atoms – which stick together like LEGO bricks meaning a whole range of well-defined architectures can be developed with great ease.

The molecular sensing aspects of this new material are related to the potassium and lithium ions, which sit loosely in cavities in the framework. These can be displaced by other positively charged ions such as transition metals or small organic molecules while at the same time leaving the framework intact.

These characteristics highlight some of the many potential uses and applications of POM frameworks, but their principle application is their use as catalysts – a molecule used to start or speed-up a chemical reaction making it more efficient, cost-effective and environmentally friendly.

Moving from lego to pasta with a short stop at the movies, we have MIT researchers describing how they and their team have found a way to ‘imprint’ computer chips by using a new electron-beam lithography process to encourage copolymers to self-assemble on the chip. (Currently, manufacturers use light lasers in a photolithographic process which is becoming less effective as chips grow ever smaller and light waves become too large to use.) From the news item on Nanowerk,

The new technique uses “copolymers” made of two different types of polymer. Berggren [Karl] compares a copolymer molecule to the characters played by Robert De Niro and Charles Grodin in the movie Midnight Run, a bounty hunter and a white-collar criminal who are handcuffed together but can’t stand each other. Ross [Caroline] prefers a homelier analogy: “You can think of it like a piece of spaghetti joined to a piece of tagliatelle,” she says. “These two chains don’t like to mix. So given the choice, all the spaghetti ends would go here, and all the tagliatelle ends would go there, but they can’t, because they’re joined together.” In their attempts to segregate themselves, the different types of polymer chain arrange themselves into predictable patterns. By varying the length of the chains, the proportions of the two polymers, and the shape and location of the silicon hitching posts, Ross, Berggren, and their colleagues were able to produce a wide range of patterns useful in circuit design.

ETA (March 18,2010): Dexter Johnson at Nanoclast continues with his his posts (maybe these will form a series?) about more accuracy in reporting, specifically the news item I’ve just highlighted. Check it out here.

To finish on a completely different note (pun intended), I have a link (courtesy of Dave Bruggeman of the Pasco Phronesis blog by way of the Science Cheerleader blog) to a website eponymously (not sure that’s the right term) named physicssongs.org. Do enjoy such titles as: I got Physics; Snel’s Law – Macarena Style!; and much, much more.

Tomorrow: I’m not sure if I’ll have time to do much more than link to it and point to some commentary but the UK’s Nanotechnologies Strategy has just been been released today.