By Michael F. Carmichael
April 16, 2009
What do a DeWalt 36-volt battery-operated power drill, a G.E.T. ‘green’ synthetic motor oil, and a pair of Land’s End no-iron twill chinos have in common? They all have some underlying application of the emerging science of nanotechnology. What does that mean?
Background
To provide some perspective on the nano world we turn to a primer published by the National Nanotechnology Initiative, a multi-agency coordinating body for federal governmental efforts at the nano scale.
How small is a nanometer? By definition, one nanometer is a billionth of a meter, but that’s a hard concept for most of us to grasp. Here are some other ways to think about how small a nanometer is:
-¢ A sheet of paper is about 100,000 nanometers thick.
-¢ If you’re a blond, your hair is probably 15,000 to 50,000 nanometers in diameter. If you have black hair, its diameter is likely to be between 50,000 and 180,000 nanometers.
-¢ There are 25,400,000 nanometers per inch.
-¢ A nanometer is a millionth of a millimeter.
OK. That’s really small. But what does it mean to the general public, particularly to business?
For one thing, it is estimated to have a $3-plus trillion impact on business by 2015, with more than $145 billion worth of nano-enabled products produced in 2007, according to Lux Research, a research company that follows the nanotech industry. These products range from the batteries for electric drills and stain resistant chinos to new methods of disease detection and cure to the lighter weight and stronger steps on a GM van. In all, more than 800 companies are producing, and selling, some aspect of nanotechnology.
What makes materials modified at the nano level different is that materials can behave very differently at that scale than they do in the larger-sized world. Again, turning to the NNI for an example, they suggest thinking of a piece of gum that’s been chewed and formed into the shape of a ball. Imagine that ball being stretched into as thin a sheet as possible. The surface area of the sheet ends up much greater than when it was ball-shaped. When the sheet dries out it becomes much more brittle faster than the ball would have been because more air contacts its surface.
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Carbon, one of the most basic of materials, can be rolled into ‘nano-tubes’ that serve as excellent conductors of electricity, something that doesn’t happen with a lump of coal. Silver, which looks good in a ring on a woman’s finger, can serve as a sunscreen when nano-sized flakes are added to her facial cream. Are these materials changing at some molecular level?
Dr. Martin Philbert, director of the center for risk science and communications at the University of Michigan, explains that “things don’t change,” he explains. “Effects that are negligible in the bulk materials become more prominent at the nano scale. It’s not there are chemical changes or that there is new physics or new biology, it’s that you’re at the scale of biology.
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There are interactions with the physical world and the biological world at the nano level that we have not been used to thinking about at the bulk scale and now they can become important. Something that’s rigid at the bulk scale becomes more elastic or deformable at the nano scale.”
An example of this newly discovered capability is something called quantum dots or q-dots.
“Combinations of metals or metalloids suddenly take on different colors,” continues Philbert, “it’s based not on their chemistry, but purely on size. Cadmium-selenide quantum dots can have different colors, but have the very same chemical identity - it’s just the size of the material that causes it to reflect light differently. Of course,” he continues, “the Romans knew this some time ago when they used colloidal gold to stain ceramics and glass.” One practical application of q-dots is the ability to ‘tune’ them to react to materials in cancerous cells that aren’t present in normal cells, leading to earlier detection.
The next application of nano-scale materials in the medical clinic most likely will be delivery devices. Dr. James Baker, director of the Michigan Nanotechnology Institute for Medicine and the Biological Sciences, is working, according to Dr. Philbert, on the ability “to tuck into the spaces of specific molecules a variety of useful and therapeutic drugs” that can then be delivered by injection or on the surface, depending on the application.
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He continues, “There is a variety of nano-scale approaches that are being developed simultaneously for an enormous number of applications, but they’re only nanotechnologies in the sense of size. They have very different functionalities, they have very different advantages and they likely will have very different issues that need to be addressed in terms of safety.” How should those issues be addressed?
“I think the FDA has it right, on a case-by-case basis,” responds Dr. Philbert. “Certainly for nano-based medicine the FDA is charged with making sure the material is safe and effective. I think that is a very good metric. We are in the early frontier days of nanotechnology and it’s unlikely that we will know all of the things we should be looking for,” he says. “For the National Research Council committee that I vice-chaired on the safety of nano-materials, says it is apparent in the report that the committee feels that we do not have a national strategy for addressing the health impact, the environmental impact, the safety impact of nano-materials.”
Philbert continued, “We need to generate a body of knowledge about nano-materials that will inform national policy making, decision-making and rule-making. We could, as an example, develop a national data repository for nano-scale materials of all sorts that contains not only positive hazard-based data but also has high quality negative data that allows us to make an informed risk extrapolation or analysis.”
It is the concept of risk analysis rather than simply relying on the idea of ‘hazardous’ that Philbert stresses. “We can be exposed to a hazardous material or event for such a brief or transitory period that it is negligible from a risk standpoint. On the other hand, there are situations when we are exposed to materials that are hazards in which we are currently unaware. At the nano scale we need to learn more about the ways in which we might be exposed so we can better assess the risks.”
While there are very large companies either looking at nano-scale applications or already utilizing them, often it’s companies at the nano-scale themselves that are the innovators. They often get their start at an incubator, such as the one at the CMU-Research Corporation, headed by Ken Van Der Wende. A joint venture with Central Michigan University in Mt. Pleasant, CMU-RC provides a variety of services to the many start-up companies within its walls. Van Der Wende, a 30-year-plus veteran of Dow Chemical and whose position is underwritten by Dow, says that the organization is a magnet for high-tech start-ups.
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“We have a 17,000 square-foot ‘wet’ laboratory, that’s best in class, equal to any Dow has anywhere in the world.” It’s also beneficial that Mt. Pleasant is one of Michigan’s 11 “smart zones” and the companies can be the beneficiaries of a variety of tax incentives.
“CMU has a vision, a desire to make its mark on the world,” continues Van Der Wende. At CMU-RC, they evaluate potential tenants on the basis of markets, such as energy or bio-fuels, water mediation and green chemistries and life sciences - primarily health and medical.
One of the tenants, Bio-Nano Power, headed by Dr. Nathan Long, “is developing smaller and faster biosensors so that diabetes patients can better monitor their glucose levels,” says Van Der Wende. “Bio-Nano Power cells are nano-scale sized particles that are activated by enzymes within the body to generate power; these particles can be aggregated or polymerized to form larger systems to generate high density power, yet are biocompatible in biological systems without additional fabrication steps and can carry materials such as pharmaceuticals for targeted sensed delivery.” Bio-Nano Power has just received additional funding by the state to continue their research.
Van Der Wende goes on to explain that, in addition to the wet lab, CMU-RC provides “technology platforms, or infrastructure, that work across the industries that we’re trying to develop. Nanotechnology is one of those industries because it plays across every one of those four market sectors. We’ve made the strategic decision that these are where there will be new jobs in the future. So this is where we’re making our internal infrastructure investments, to serve our tenants in those areas.”
“In effect, we drive our resources into emerging sectors such as health informatics,” Van Der Wende explains.
Asked if this effort will be affected by the government’s economic stimulus programs devoted to converting all medical records to electronic form, he explains, “Our tenants in the medical informatics field are way ahead of the government in that area. We’ve been able to leverage the University’s advanced analytics and predictive modeling in addition to a large grant and we’ve been working for the past couple of years to digitize medical records. Now that we have the digital information we can take it to the next space. Using neural networks we can actually get into predictive medicine,” he says.
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“One of our companies, Q-Array, is using nanotechnology on a medical DNA basis to start predicting what you may get as a disease and get out ahead in treating it,” notes Van Der Wende. “Another of our companies, Bauer BioMedical, is developing break-through technology that promises to make detecting pancreatic cancer - one of the deadliest forms of cancer - as easy as a trip to the drugstore and as early as two years sooner than current science allows. They have a patented non-invasive, genetic-based test is currently under development and it holds enormous promise for its developers and for the health science industry.”
What else is happening in the nanotechnology field? Dr. Mark Hersam, professor of Materials Science and Engineering and Professor of Chemistry at Northwestern University says a number of applications “depend how you define nanotechnology. Intel is currently selling 32 nm (nanometer) transistors, so you could argue that every computer is an example of nanotechnology.
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Similarly, USB memory sticks and the iPod Nano exploit flash memory whose underlying physics is the inherently nanoscale and quantum mechanical phenomenon of tunneling. In addition, stain-resistant fabrics are typically embedded with hydrophobic nanoparticles [the reason those chinos are stain-resistant] and many cosmetics utilize nanoparticles that absorb ultraviolet light in an effort to improve their utility as sunscreen. Also, many sporting goods (e.g., tennis rackets, golf clubs, and baseball bats) are now fabricated from nanocomposite materials that are embedded with nanoparticles or nanotubes.”
Corp! asked Dr. Hersam what headlines we might be reading five years from now that involve nanotechnology. “Advances in electronics resulting from miniaturization are inevitable,” he answered. “The real question is whether or not nanotechnology will have a real impact in the biotechnology and health sectors. Since the general public tends to be most interested in biotechnology and health care, it is likely that advances in these areas will grab most of the headlines.”
University of Michigan’s Professor Philbert says that often scientific advances are “a matter of luck. Some things may have issues that pop up in testing; others may have incredibly high functionality and find uses in ways other than intended, so it really is difficult to predict. We’re standing at the gate, and some of us may have cracked the gate open a bit and have entered the field, but I don’t think we have yet realized the full potential and impact of nanotechnology.”
As wonderful as nanotechnology seems, Philbert remains a cautious scientist. “We don’t yet know the lifecycle of those nanomaterials that are in the marketplace now and how they will affect the environment or the user. As a scientist, it’s the ‘not knowing’ that bothers me. How are going to manage the risk of these materials as they flow through our economy, our environment?” he asks.
“The risk factor varies considerably if you are dying of a disease or if you’re eating something or applying sunscreen. There are many things that we do that are hazardous - take driving a car, probably the most hazardous thing we’ll do today - but we manage that hazard and reduce our exposure to those parts of driving that are most likely to cause injury or death. We have brakes on the car, not just brakes but anti-lock brakes. We have airbags. We lock our doors and put our seatbelts on. We drive responsibly and slow down when we perceive there’s an issue ahead. That’s the level of thoughtfulness we need to bring to nanotechnology.”
