The State of Nanotechnology

The State of Nanotechnology The Technology Investor archives Think Small… Reeeally Small By Doug Hornig, Senior Editor ...

1 downloads 71 Views 382KB Size
The State of Nanotechnology The Technology Investor archives

Think Small… Reeeally Small By Doug Hornig, Senior Editor Of all the new technologies currently impacting our world, the one that may just have the most powerful long-term consequences is one we cannot even see. That is nanotechnology. Nano has kind of snuck up on us. When it's talked about, it's generally referred to as something that is still pie in the sky – years, or decades, or even centuries off. Few people realize how much it is already a part of our everyday existence, nor the profound changes that lie just over the horizon. There is no hard and fast definition of nanotech. But it is, broadly speaking, the science of manipulating matter at the atomic or molecular level. It generally deals with developing materials, devices, or other structures with at least one dimension in the 1-100-nanometer range. (One nanometer is a billionth of a meter; a DNA double helix has a diameter of about 2 nanometers; 10 nanometers is 1/2,500 of the diameter of a human hair.) Finished items are built, so to speak, from the very bottom up, according to the principles of "molecular recognition." As scientists have developed the techniques for working at that microlevel, they've discovered that some very strange, wonderful, and ultimately highly useful things can happen… things we never envisioned before we looked that deeply into the physical world. Bottom line, the promise held by nanotech is, for all practical purposes, without limit. However, there are still many challenges and years of work ahead of the field before we begin to see the kind of revolutionary change that some futurists have predicted will come from the near-atomic-scale engineering discipline. Authors like acclaimed sci-fi writer Neal Stephenson paint a brilliant picture of its applications: a world where your every want is possible, from diamond buildings to machines that heal our bodies from the inside. Others

depict its terrible dark side, where nanotech is capable of producing frightening new weapons and suffocating surveillance tools. While that world is hardly upon us yet, we also needn't take our projections quite so far out to be amazed at the power of this technology. The last few years have seen a colossal increase in nanotech innovation and success, and what we have already achieved is impressive in its own right. A few examples: Nanoparticles. Some of the most basic work in nanotech was devoted to synthesizing nanosized particles of the underlying element. Of those created so far, silver nanoparticles have been by far the most utilitarian, with applications in catalysis, optics, and electronics. They are employed as a potent antibacterial/antifungal agent in textiles and wound dressings, as a coating on surgical instruments, and in wastewater treatment systems. They're added to hundreds of consumer products, including food storage containers, computer keyboards, cosmetics, pillows, and cell phones. Chances are, you touch something nano-enhanced every day. Nanomedicine. Nanotech will likely revolutionize health care – and not just in sterilizing the OR. The list is long, but take the quest for a cancer cure, for example. One technique already being tested on animals delivers anticancer drugs in packets of nanoparticles to the tumor, where they accumulate. Ultrasound can then be directed at the target, popping the bubbles and releasing the drug within a well-defined area. A second, unrelated line of research uses antibodies to deliver a packet of gold nanoparticles to the cancer cell. An intense, focused laser beam is then used to explode the nanobubble, bursting the cell. And yet another oncological effort is Kanzius RF Therapy, which aims to insert metallic nanoparticles in or around cancerous cells and then excite these particles using radio waves. The energy from the radio waves heats the metal, which burns the cancerous cell cluster. (For more on this subject see our recent article, The Promise of Nanomedicine.) Another startling innovation is "flesh welding." This is projected as a replacement for the clumsy, infection-prone, mechanical stitching that has been employed in surgery forever. The principle has already been experimentally demonstrated. In the procedure, a liquid containing nanoshells – spherical nanoparticles consisting of a dielectric core covered by a thin metallic shell (usually gold) – is dribbled along the seam to be closed. An infrared laser is then traced along the seam, causing the two sides to weld together. Not only is this less messy, it could be a lifesaver, solving the difficulties and blood leaks caused, for example, when a doctor tries to restitch the arteries that have been cut during a kidney or heart transplant. The flesh welder could repair the artery perfectly, with much less dependence on the surgeon's manual dexterity.

Nanocrystals. Several efforts are under way to harness nanostructures' unique properties to improve the performance of solar cells. One approach makes use of a type of nanowire called "nanoflakes." With a perfect crystalline structure, nanoflakes are capable of absorbing nearly all light directed at them, according to the company doing the research. These can be used to build low-cost solar cells with about 30 percent efficiency, roughly double that of the average solar cell available today. Carbon Nanotubes (CNTs). These are among the most utilitarian structures yet discovered and are in commercial use today. CNTs are an allotrope (variant form) of carbon, an element we know to be peculiarly adaptable to structural rearrangement, from soft graphite to diamonds, the hardest known natural mineral. In order to form the allotropes, carbon atoms array themselves in a wide variety of ways, from the simple lattices of graphite, to graphene's honeycombs, to the geodesic spheres known as buckyballs, to the single-walled cylinders that are nanotubes. CNTs' appeal is that they are among the strongest and most conductive materials known. Add in that they are extremely lightweight and you have quite an attractive building material. Researchers dream of making super-efficient electrical transmission lines or the skins of airplanes out of them. The difficulty has been in creating larger materials that reflect the remarkable properties of individual nanotubes. But a small, privately held startup, Nanocomp Technologies, has succeeded in producing flexible, paper-thin sheets of carbon nanotube fiber many meters long. The process involves shooting a mixture of alcohol and an iron catalyst into a hightemperature furnace under pressure, causing the carbon atoms in the alcohol to bind together to form long nanotubes. Nanocomp's sheets are still not as strong nor conductive as individual nanotubes, but they're able to provide a lighter replacement for copper and other conventional materials in some applications. Early customers include NASA, which employed nanotube sheets to protect its Juno deep-space probe – launched last August – from electrostatic discharge, and the US military, which aims to use the sheets to reduce the weight of the electrical cables on unmanned drones by half, thereby increasing flight times. It's a first step toward creating the ultimate building material, something that may eventually replace steel cables in suspension bridges. Other potential applications for carbon nanotubes, to name but a few, include: an additive to concrete to increase strength and resist cracking; stronger and lighter tennis racquets, golf clubs, and baseball bats; synthetic muscle implants; body armor that's far tougher than Kevlar; waterproof and tear-resistant fabrics; more efficient desalination than conventional reverse osmosis; and on and on. Most visionary of all, some dreamers believe CNTs could be used to create a tether for an elevator to outer space.

For millennia, human life changed but little from one century to the next. Now, amazing new technologies seem to be arriving on our doorsteps on an almost-daily basis. So rapid is the pace of change that we're probably subject to what might be called "tech fatigue." We may not be prepared for what lies ahead – but ready or not, we're being propelled into a future totally different from our past, and nanotech is right in the middle of it all. This wide-ranging field of study may just become the virtual equivalent of the ancient alchemists' Philosopher's Stone. We may never be able to transmute lead into gold, but nanotech will allow us to reorder our physical world. Profoundly. (For those interested in seeing how this might happen, here's an entertaining video showing a potential future nanofactory.) From a speculator's viewpoint, nanotechnology is such an embryonic field that it's difficult to invest in. There is no obvious market leader, nor is one likely to emerge soon. Each application of the science is profoundly different than the ones before it, meaning that no one company can meet the needs all the different niches that the highly specialized applications serve today. This has meant through today that the pioneers in the sector are virtually all small startups, privately held and funded. The few available to public investors are either non-pure-play ventures, which derive most of their revenue from other, lessgrowth-intensive sectors like traditional chemicals, medicines, or manufacturing, or they are only available through business development companies that specialize in early stage venture investing, like Harris and Harris (TINY), where the payoff timeframe in years can be counted on two hands… or even longer. But this doesn't mean that investors won't get to participate in the nanotech revolution. They will – in time. Already, a trickle of specialized companies is going public. It won't be long before the difficulty won't be finding something worthy of investment, it'll be separating the ultimate winners from the losers. We're looking forward to that day.

Bits & Bytes Going Mobile (Business Insider) We have often written about the extraordinary speed at which the world has embraced mobile communications and computing. But sometimes, there is just no substitute for a visual representation. This is a very informative slide deck on the future of mobile. Crossed Wires (Daily Mail) For a long time, scientists have wondered how the brain is actually wired up. While we're still missing some pieces of the puzzle, researchers at Massachusetts General Hospital recently solved a part of it, using a new, state-of-the-art magnetic resonance imaging (MRI) scanner. It turns out that the brain is not a mass of billions of nerve fibers, tangled like a huge bowl of spaghetti. Instead, it's a grid structure, consisting of 2D sheets of parallel

neuronal fibers that cross paths at right angles, like the warp and weft of a fabric. Along with the story are some very cool photos. New Cancer Fighter (Medical News Today) Cancer treatment may have taken a leap forward with the results of early trials at Stanford University. A single antibody caused tumors from seven different human cancers transplanted into mice to shrink or disappear, according to a new study. The researchers hope to move on to Phase I and II tests in humans within the next two years. Going Super (gizmag) Finally, here's one of the latest – not to mention silliest – applications of 3D printing to hit the streets. Always wanted to be a superhero? Now you can… well, at least symbolically. UK novelty company Firebox will create a 3D-printed model of your head, which you can stick on any one of five supplied superhero action figures. Female Batmen and male Wonderwomen – hey, why not? At nearly $130, it isn't cheap, but then attaining superherohood probably shouldn't be.