Chapter 3: What Nanoscientists Are Working On – NanoInnovation: What Every Manager Needs to Know

What Nanoscientists Are Working On

The real nanotech pioneers aren't those with just grand ideas, but rather those who make them happen.

Chad Mirkin, Northwestern University

Every discipline and industry has its own set of world-changing nanoscience targets. Some of these are being worked on quietly out of the public spotlight, while others are trumpeted almost daily in the media. Many of these science goals sound simplistic when you hear about them on the Discovery Channel or in the New York Times, such as invisibility cloaks, miraculous cures for cancer, or materials that are stronger than steel.

The reality is that all of these so-called miracles get their start in a science laboratory – in government laboratories such as the National Science Foundation, NASA, the US Navy, and DARPA; at corporations like Bayer, Eastman Kodak, Fraunhofer, IBM, Lockheed Martin, Nippon Electric, Nokia, and Samsung; and most notably, on hundreds of university campuses around the world. Many science centers are university–industry collaborations, such as the Binnig and Rohrer Nanotechnology Center in Zurich, Switzerland; part of a $90 million shared research infrastructure developed by IBM and ETH-Zurich (the Swiss Federal Institute of Technology).

Of course, before any science-based nanoinnovation can be implemented and commercialized – long before companies and families can reap the benefits – a scientist in a laboratory, somewhere in the world, has to find a way to bend or slow, or stop and start, the first ray of light. Someone has to place the first drug molecule in a nanoshell, deliver it safely to a human cancer cell, and destroy the first tumor. Someone has to make the first nanotube, and the first few flakes of graphene. Someone has to go first.

The real miracle of nanoscience is the perseverance, dedication, and commitment of the nanotechnology scientists and their teams who are working to make these things happen. These teams include students and laboratory technicians as well as Ph.D.s and research directors. They don't all win awards, but they all push the frontiers of science, even if they fail – because failure helps define the pathways to success. The rewards – from the eureka moments to the commercial successes – don't happen overnight. When they happen, it's like someone set off a fireworks display. From one breakthrough, whole new worlds of discovery are unleashed. That's what we mean when we talk about waves of innovation, and the incredible exhilaration that comes from surfing these turbulent waves.

As a manager, you need to keep your eye on nanoscience because this is where most of the nanoinnovations come from. If your job involves emerging technologies, you need to know which of the myriads of science projects have the potential to demonstrate proof of concept, to survive a rigorous testing process, to scale up to production levels, and find safe uses in products and systems. You need to learn to distinguish science hype from science reality so you can evaluate which innovations are looming on the near horizon. You need to get a sense of which innovations are on a fast track to commercial development, and which are going to remain in the laboratory for another decade or more.

Knowing what scientists are working on will help you identify commercial opportunities, potential collaborations, where and when to invest, and how to select nanotechnologies and applications that synch with your interests. In this chapter, we'll look at some nanoinnovations that had their beginnings in research labs. We'll meet some very cool nanoscientists, and look at some science-scanning techniques that will help you stay up-to-date with scientific discoveries and breakthroughs.

3.1 Using Nanoscience to Solve Puzzles and Unlock Innovations

Nanoscience involves chemistry and physics, but you don't have to be a chemist or physicist to understand the subject. My wife Nancy is a medical research technician involved in research to develop improved materials for use in medical implants and devices. I'm deeply impressed with how easily she can draw images of organic molecules, understand protein folding schemes, and analyze nanoscale images for research projects. When I ask her how she wraps her mind around these complexities, she just smiles and says, “It's all about puzzles.” She's right. It helps if you like solving puzzles, because the challenges facing nanoscientists are similar to the challenges faced by any puzzle solver.

In the field of nanoscience, much of the early puzzle-solving begins in a university research laboratory. As you will see from the examples in this book, academic research is a starting point and anchor for most of the nanoinnovations that eventually become commercial products. Many of these projects involve partnerships between faculty researchers and corporations. For example, at Caltech, Paul Rothemund has been working with Intel to figure out how to get a tangled forest of nanotubes to line up in an orderly pattern or matrix so they can be used in a new generation of computer chips.

Many nanoscientists are working on innovations that have the potential to provide social benefits that are desperately needed, such as cures for diseases and ways to regenerate failing organs and tissues. At Wake Forest University, Anthony Atala and his team are using modified inkjet printers and nanoscaffolds to create new organs from patient tissue, which could one day replace the need for donated organs. Michal Lipson and her colleagues at Cornell are using metamaterials to bend light, which may lead to the development of an invisibility cloak – or a new type of lens that can treat some forms of blindness.

Some of the problems that scientists are working on are of special importance to people living in Third World countries and remote regions of the world. For example, in Bangladesh, where arsenic contaminates as much as 70% of the drinking water, arsenic poisoning is an endemic health problem. At Rice University in Houston, Texas, Vicki Colvin and her colleagues have demonstrated that nanoparticles of iron oxide (nanorust) can be used as an inexpensive method for removing arsenic from contaminated water. The research team included Dr. Colvin, her colleague Mason Tomson, and their students [1]. When contaminated water is mixed with nanorust, the arsenic clings to the iron particles that clump together and can be removed with an ordinary magnet. This discovery paved the way for a low-cost method to remove arsenic from contaminated drinking water, which may help people living in Bangladesh and other countries where arsenic contamination is a major problem.

It is important to note that scientific research begins from basic or fundamental research that demonstrates what can be done with a particular atom or molecule. There is not always a direct link between a basic research discovery and a commercial innovation, but if there were no basic research there would be no nanoscale microscopes, no carbon nanotubes or graphene, and no flexible electronics or thin-film solar cells.

There are many long-standing goals that scientists have been trying to achieve that can only be unlocked by basic, fundamental scientific investigation and experimentation. For example, you would think that by now we should know everything there is to know about water. But this is not true. Water is difficult to study because it is not easy to isolate and observe individual water molecules. That is because water typically exists as a network of molecules that link and bond in liquid water or ice.

In 2011, a team of Japanese scientists trapped a single molecule of water inside a carbon buckyball, which is difficult considering that water molecules are almost always found attached to other water molecules because of the way they form hydrogen bonded networks, and buckyballs are typically slightly hydrophobic [2]. The scientists used temperatures and water vapor pressures to open a C60 carbon molecule (buckyball) and then inserted a water molecule in the hollow cage-shaped structure and closed the carbon framework.

These are only a few of the thousands of innovations being developed by nanoscientists, but they illustrate the enormous technological revolution that is occurring across the incredibly broad spectrum of exploration that we call “nanoscience.” Let's look at some more interesting examples.

3.2 Solid Smoke: Catching the Comet's Tail

Scientific discovery is often like trying to catch the tail of a comet, so it is ironic that a nanoscience discovery called aerogel – sometimes called “solid smoke” – allowed NASA to catch and analyze the dust in a comet's tail. In 1999, NASA sent a space probe to collect dust samples from a comet called Wild 2. The probe returned to Earth with the sample in 2006.

When NASA scientists were designing the Stardust space probe, they had to deal with the challenge of collecting the dust particles, which ordinarily would vaporize when they come into contact with a solid material. A set of ultralow-density aerogels was used in the Stardust Interstellar Dust Collector to catch and trap the dust grains from the trail of the comet. A form of silica aerogel is also used to insulate the Mars rovers that have been transmitting stunning photos and data from the surface of Mars. Aerogel is also used to insulate space suits.

Aerogels are comprised of up to 99.8% air, which is trapped in individual pores just a few nanometers in size. Aerogel is translucent and has the least density of any porous solid material, which is why it is sometimes called “solid air” or “solid smoke.” If you hold it in your hand it feels light as a feather and has the consistency of spongy gelatin. A block of aerogel the size of a person weighs less than a pound and can support an object weighing half a ton. Aerogels can insulate against extreme temperatures and are about 40 times more effective as an insulator than fiberglass. The unique properties of aerogels come from the nanosized bubbles – the spaces in the material. These air bubbles or gas pockets can range from 2 to 100 nm or more.

The accompanying photos from NASA's Jet Propulsion Lab (Figure 3.1a and b) vividly show the insulating properties of aerogels. These photos show crayons and matches being insulated from the heat of a small blowtorch by a thin layer of a feather-light aerogel made from silicon dioxide. The crayons in the photo are made from a mixture of paraffin wax and color pigment, which melts between ∼53 and 64 °C (128 and 147 °F). Safety matches burn at 230 °C (446 °F). The blowtorch flame can exceed 1000 °C.

Figure 3.1 (a) Aerogel protecting crayons from melting. (b) Aerogel prevents matches from igniting (source: NASA/JPL).

Aerogel was created in 1931 by Samuel Stephens Kistler (1900–1975), an American scientist from California who (according to popular folklore) developed the material to win a bet to see who could replace the gas in a “jelly jar” without causing any shrinkage. The material languished for several decades until the 1980s when new manufacturing methods and the rise of nanotechnology gave aerogels the impetus needed to become commercially viable. Today, aerogels made of silica, carbon, alumina oxide, and other materials are used in building insulation, skylights, scuba diving suits, tennis racket handles, supercapacitors, and so on. They are used in crime laboratory targets to test ballistics.

The global market for aerogels was estimated at less than $90 million in 20081) and has been projected to surge to as much as $1 billion by 2015 [3]. This growth is expected to be driven by applications related to thermal and acoustic insulation. This is one example of a science-based nanoinnovation with space-age applications and significant commercial value.

3.3 Turning DNA into Boxes, Lattices, and Pyramids

The following stories are based on interviews with several nanotechnology pioneers. These scientists are representative of the many thousands of researchers who are working 24/7 in laboratories around the world, often without credit and out of the media spotlight, to break down a barrier or unlock a secret that will improve our lives.

Nadrian (Ned) Seeman (Figure 3.2) is an American nanotechnologist and crystallographer who is internationally known as the inventor of DNA nanotechnology – the use of DNA molecules as a structural material to create rigid two- and three-dimensional structures with nanometer precision. Dr. Seeman started his research in the early 1980s and has worked for >30 years in the field that he created and pioneered. He has published >240 research papers and is a recipient of the Feynman Prize in Nanotechnology. In 2010 he was the corecipient of the million dollar Kavli Prize in Nanoscience.

Figure 3.2 Nadrian (Ned) Seeman, the inventor of DNA nanotechnology (photo credit: Mike Summers) (NYU Photo).

Most of us think of DNA as a carrier of genetic information in living cells. DNA – deoxyribonucleic acid – is the chemical in the nucleus of all cells that carries the code of life. DNA is also a polynucleotide, which is a chemical polymer – a polymer is a large molecule composed of repeating structural units. A DNA molecule consists of two strands formed in the shape of a twisted ladder (the iconic “double helix” discovered by Nobel Prize winners Watson and Crick). The legs of the ladder are made of two long strands of deoxyribose sugar and phosphate molecules, bound together by four different types of nucleotides or “bases” that are labeled A (adenine), G (guanine), C (cytosine), and T (Thymine). In a DNA molecule, A on one strand pairs with C on the other strand, and G pairs with T. The legs of these ladders can be chemically sliced, separated, and manipulated so that they attach to other “sticky” DNA strands to design objects, lattices, and nanomechanical objects. The DNA strands used in DNA nanotechnology are organic molecules that are synthesized by programming the A, G, C, and T bases; however, it should be emphasized that these synthesized molecules and strands were never part of “life” or living systems and there is nothing “Frankensteinian” about this research.

Dr. Seeman and his colleagues have created DNA crystals that can self-assemble into 3D forms through synthetic sequences. In partnership with Nanjing University in China, Dr. Seeman has explored the potential to build a “DNA assembly line” that uses hundreds of short DNA strands to mold a very long DNA strand into any shape. Programmable DNA “machines” are attached to these shapes, which allow the researchers to direct the assembly using what is essentially a nanoscale robot arm. An impressive achievement from this process is the creation of a DNA “walker” that moves along the assembly line, stopping at the DNA machines to collect and carry the DNA cargo components such as metallic nanoparticles. By switching the devices between “on” and “off” states, the walker can determine which cargo will be transferred, or not transferred. Is this an early demonstration of Eric Drexler's vision of molecular manufacturing? It could be interpreted that way. To date, DNA nanotechnology is one of the few proven techniques for creating and precisely controlling the design of complex nanoscale structures.

Dr. Seeman's research is characterized by a chain of breakthroughs that followed a path as twisting and ladder-like as the DNA molecules he has learned to manipulate. A crystallographer by training, he began applying the principles of crystal formation to the use of DNA in 1981. This led to the creation of one- and two-dimensional structures. In 1991, he and his team announced the synthesis of the first DNA structure – a cube – that was followed by other shapes. However, these structures were flexible and not rigid enough to sustain three-dimensional shapes, which led to the creation of a more rigid tile-based lattice in 1998 (in collaboration with Erik Winfree). These developments led to the development of the field of DNA computing, demonstrated in a 2004 paper by Erik Winfree and Paul Rothemund at Caltech. In 1999, Dr. Seeman demonstrated the first crude DNA nanomachine, and in 2004 and 2005 he and his team demonstrated the first DNA nanomachines that exhibited mechanical motion – in other words, “walkers” that moved. Building on Dr. Seeman's discoveries, Paul Rothemund developed a DNA folding technique now called “DNA origami,” which was an easy way to create DNA molecules of virtually any shape. In 2009, Seeman demonstrated the synthesis of a three-dimensional lattice, an achievement he originally conceived as a concept, 30 years earlier. In 2010, Dr. Seeman and his Chinese colleagues described a programmable DNA nanoscale assembly line [4].

In January 2012, a team of researchers from Kyoto University and the University of Oxford reported that they successfully used DNA building blocks to construct a motor capable of navigating a programmable network of tracks with multiple switches. Their research used DNA origami to cause strands of DNA to self-assemble into 2D and 3D structures, thus forming a DNA “rail system” that motor molecules could traverse. The team included Dr. Masayuki Endo and Prof. Hiroshi Sugiyama at Kyoto University's Institute for Integrated Cell-Material Sciences, and Dr. Shelley Wickham at Oxford University. The researchers hope to build on their research to develop programmable molecular assembly lines and more sophisticated sensors [5].

A Pub, Some Fish, and a Nanoscience Eureka Moment

In an interview for this book, Dr. Seeman offered some fascinating personal reflections on the chain of events that led him to his award-winning discoveries.

“By training I'm an X-ray crystallographer. In 1981 I was doing research as a postdoc. My work involved taking biological molecules and getting them to crystallize to make them amenable to using x-ray diffraction, which allowed us to work out the 3-dimensional structure of the molecule that makes up the crystal. This is a complex process, because there are different types of interactions that hold the crystal together – it could be salt, water molecules, charges, etc. Once I read an article that said you have to do 26 things right to hit a home run in baseball. Growing a crystal is very similar. You need to get 9 steps right and if one of them is wrong, the crystal won't grow. I have to admit, I was awful at growing crystals. So I started looking for a way to make the molecules that come out of solution arrange themselves in an exact repeating pattern, which means a 2D would look like rows of headstones in a military cemetery, and a 3D would be like stacking those cemeteries on top of each other. Also, as an assistant professor, I was not publishing on crystallography. So I started modeling branched DNA. I figured out that you can make more than four branches.” A smile creeps into his voice as he recalls how he got the inspiration.

“One day in September 1980, I had an epiphany over a glass of beer,” he recalls. “I was wrestling with a technical problem, so I went to the campus pub to think about it. I wanted to make six arm junctions – a DNA branch in six directions. While I was thinking about that, I remembered a woodcut by the artist M.C. Escher, called ‘Depth.’ The woodcut has a bunch of flying fish going from the center. I realized that these flying fish are in principle like a six arm junction. If I took these junctures and put sticky ends on them, I might be able to force a configuration using DNA to create structures.”

“During this time, I thought our quest for 3-dimensional crystals was kind of like the quest for the Northwest Passage. As a crystallographer, I didn't know how to work with DNA in solution and we had to learn about that. First, I learned how to do 2-dimension (2D) versions, then did ‘floppy’ versions of the objects. Then I had to learn how to do ‘stiff’ motifs. One of my former students worked out how to do a 3-dimensional stiff motif and get them into a 3-dimensional structure. This process took about 30 years. It took us about 10 years just to figure out how to keep the structures from collapsing. Along the way, we learned how to organize nanoparticles in a checkerboard arrangement, and we created some specific devices that were able to capture other species. We have made a variety of mechanical devices from DNA, based on the programmability of DNA, by adding or pulling out some of the strands. About five years ago, we developed a bipedal walker that walks on a track – it moves like an inchworm. This is a nanobot-like bipedal walking device, where the rise and fall of each foot of the biped is controlled by introducing DNA strands with specific sequences into the solution.”

“Some of our colleagues have laid the groundwork for nanoscale self-assembly, which is essentially bottoms up chemistry. I may have been a crystallographer, but in essence we're all really chemists. We make stuff.”

Ned revealed that his research team is now controlling matter in three dimensions and have scaled up the structures to a quarter of a millimeter, which is large enough to see with the naked eye. “We are now making something that is very big compared to the nanoscale – which involves repeating it somewhere between 50 and 100 trillion times.” Everything is still in prototype form, and still very small, but far enough along that it is possible to envision using these repeating units to build memories and for applications in nanophotonics.

In addition to the work by Dr. Seeman and his colleagues, a growing research community has been spawned by his groundbreaking achievements.

“When I started this research 30 years ago,” he recalls, “I was the only one working in this field. Today, there are at least 50 research teams working on DNA nanotechnology.”

The Next Generation of Structural DNA Scientists

Dr. Seeman's research has spawned an entire generation of DNA nanotechnologists who are pushing the boundaries of the field he created.

In 2009, a team of researchers at the Aarhus University Center for DNA Nanotechnology in Denmark used DNA origami to form a hollow cube with a hinged lid [6]. The technique involved creating a computer program to generate a single-stranded DNA sequence that would self-assemble into the desired shape, using smaller DNA fragments as “staples.” The box measured 42 × 36 ×36 nm3, large enough to hold enzymes or virus particles. According to lead researcher Jørgen Kjems, the box can be locked shut or opened using DNA latches or “keys.” A pair of dye molecules glow red when close and green when separated, which help the researchers detect when the DNA box is open or closed. The team is working on different types of “locks” that are responsive to different conditions, which could be used in a DNA computer, drug delivery, and other applications.

Yamuna Krishnan and colleagues at the National Centre for Biological Sciences in Bangalore have reported an important step toward the vision of a DNA nanomachine that can probe the local pH inside a living cell [7]. Dr. Krishnan said his team named their DNA nanomachine the “I-switch.” It functions as a pH sensor based on fluorescence resonance energy (FRET) inside living cells. The major achievement of this research is that the Indian team has shown that a nanomachine can function inside a living cell, not just in a test tube. This proof-of-principle suggests the feasibility of using nanodevices based on DNA and other nucleic acids for applications in cell biology and biomedical engineering. Krishnan and colleagues suggest that their research could lead to the development of DNA nanomachines that could be used as sensors, diagnostic markers, and targeted therapies in living cells, although they concede that additional technological breakthroughs are needed [8].

In 2004, Dan Luo, Professor of Biological and Environmental Engineering at Cornell University, and Ph.D. grad students Soong Ho Um, Sang Yeon Kwon, and Jong Bum Lee created self-assembling DNA buckyballs that emulate carbon fullerenes (see Figure 3.3). Luo's research group is investigating the properties and unique capabilities of these structures, which measure approximately 400 nm in diameter, compared to carbon buckyballs which average 7 nm in diameter. Potential applications include drug delivery and electronics. Luo's research group has also created DNA barcodes and DNA hydrogels as part of their research, demonstrating the use of synthetic DNA as nanoscale building blocks.

Figure 3.3 These buckyballs were made from self-assembling DNA molecules by Dan Luo and his team at Cornell University. Potential applications range from drug delivery to electronics (image courtesy of Dan Luo. Copyright 2004, Cornell University).

The applications for DNA nanotechnology are complex and exciting. DNA structures can be configured to transport drugs inside cells, especially drugs that are normally rejected and prevented by cell chemistry. A container made from DNA can be accepted into the cell and camouflage the drug until it is inside a tumor cell, where it can then be released.

A collaboration between Oxford University physicists and molecular neuroscientists have shown that molecular cages made from DNA can enter and survive inside living cells until triggered to release their cargo. In a project led by Dr. Andrew Turberfield at Oxford's Department of Physics, synthetic DNA was programmed to form pyramid-shaped cages around protein molecules. The DNA cages were made from four short strands of synthetic DNA formed into a four-sided pyramid about 7 nm tall. The structure resisted attacks by cellular enzymes and remained intact inside human embryonic kidney cells for at least 48 h. This constitutes a convincing proof of the concept that synthetic DNA containers can actually be used for drug delivery, since DNA boxes or cages must be able to enter cells and survive there until needed, and then release its contents in response to some sort of signal or triggering mechanism.

“At 7 nanometers across our DNA tetrahedrons are compact enough to easily enter cells but still large enough to carry a useful cargo,” Professor Turberfield has said, noting that more work is needed to understand how DNA cages find their way inside living cells [9].

There are a lot of associated discoveries and processes that still need to be developed by nanoscientists, and the discovery stream is strong and impressive.

3.4 How Nanoinnovation Is Extending Moore's Law

Any discussion of nanotechnology would be incomplete without a discussion of the role of nanotechnology in the evolution of computing, consumer electronics, and semiconductors. As a manager, you don't need to know all the details about the role of nanotechnology in semiconductors. However, you do need to know if Moore's Law is going to keep making computers smaller, faster, with more memory and processing power – and what happens when we reach the physical limits of miniaturization.

Historically, more than 50 years of innovation have taken us from the first transistors, which were over a centimeter in diameter, to the smallest transistors today that are just a few nanometers. Michael Berger, the founder of the Web site put this achievement in context: “The first transistor used in a commercial application was in the Regency TR-1 transistor radio, which went on sale in 1954 for $49.95, which is over $375 in today's dollars. Today's world includes transistors that are ubiquitous in miniaturized electronics that drive communications, the world of the Internet, and much more.”

Michael observed that transistors have shrunk from over 1 cm in diameter to less than 30 nm, which is 3 million times smaller. “This feat would be equivalent to shrinking the 509-meter tall Taipei 101 Tower, currently the tallest building in the world, to the size of a 1.6 millimeter long grain of rice.” This process of miniaturizing computer circuits follows a pattern known as “Moore's Law.”

Moore's Law is based on Intel cofounder Gordon Moore's 1965 observation that the number of components in integrated circuits had doubled every year and would continue to double until at least 1975. His prediction was published in a classic article in Electronics Magazine (April 1965). In 1975, he adjusted his prediction to a doubling of circuits and processing speed every 2 years and this became the standard metric we call Moore's Law. In practice, Gordon Moore's prediction became a self-fulfilling prophecy when Intel, and the semiconductor industry in general, incorporated his convention into their long-term planning and design targets. This law has been extrapolated to include pixel density and other measures associated with computing and consumer electronics and is now the gold standard for innovation-driven growth in the electronics industry.

In the semiconductor industry, Moore's Law is often expressed in nanometers. Semiconductors are essentially on–off switches that include a source of flowing electrons, a gate that controls the flow through a channel, to a drain where the electrons go. Flowing current is interpreted as a “1” or “on” condition, and when the current is not flowing, that is interpreted as a “0” or “off” condition. The size of the gate has been at the nanoscale since 2000, and in 2014 shrank from 22 to 14 nm. Scientists predict that there will come a point – somewhere ∼5 nm – where quantum effects will affect the physical electron flow and new architectures will be required.

In 2010, I was hosting the annual Emerging Technologies Update Day, an event I originated at the Wharton School – the theme was the “Future of Computing” and one of the questions I asked the speakers was whether and how long Moore's Law would continue. When I posed this question to Mike Mayberry, VP-Technology and Manufacturing and Director of Components Research at Intel, he weighed in on the plus side, predicting that the “law” would keep going. Why did he believe this?

“Because we've already hit the wall twice and found ways around it,” he said with a broad grin.

In 2011, Intel “broke the wall” again when it introduced a 22 nm microprocessor code-named Ivy Bridge. This device uses a three-dimensional architecture called tri-gate and represented a “reinvention” of transistor architectures. The significance of this innovation is apparent in the side-by-side comparison of the old and new architectures (shown in Figure 3.4), which show a dramatic increase in the circuit density on the new chip.

Figure 3.4 It's easy to see the improvement in the architecture of Intel's three-dimensional tri-gate technology (b) over the previous circuit architecture (a). Intel's tri-gate transistor was first announced in 2002, and in 2011 became the first three-dimensional transistor to be put into high-volume manufacturing. The 3D architecture was first used in a 22 nm Intel chip codenamed “Ivy Bridge” and is expected to lead to the development of 10 nm circuits by 2015 (image source: Intel Corporation).

Of course, it is inevitable that Moore's Law will slow at some point and chip designers will hit a physical barrier. Estimates for when this will happen range from 2021 to 2029.

Why is this important?

For nanoinnovators, finding a way past this wall provides the semiconductor industry with a major research target. There are hundreds of teams working on ways to develop new materials and designs that will maintain the phenomenal growth that has powered the evolution of smart electronics. No one knows if the ultimate solution will involve relatively new physics – such as plasmonics, spintronics, or photonics – or biological computers made from DNA, or something we haven't seen yet.

In 2012, geneticist and genome pioneer George Church and bioengineer postdoc Sriram Kosuri at Harvard University's Wyss Institute announced they were able to store 700 TB of data in 1 g of DNA, which established a new record for biological data storage [10]. The data stored on the molecule were the text of Dr. Church's new book – 53 426 words. This research is supported by the US Office of Naval Research, Agilent Technologies (which makes DNA microchips), and the Wyss Institute. Dr. Church was a leader in the Human Genome Project in the 1980s and 1990s, and is the founder of the Personal Genome Project which hopes to sequence the genomes of 100 000 people.

When it comes to biological computing, the ultimate solution is to develop a circuit that uses just a few atoms. This has been done in the laboratory. In 2012, the world's smallest magnetic storage unit was engineered from just 12 iron atoms by a team of researchers at IBM Research-Almaden. Lead investigator Andreas Heinrich explained that the team posed the question: “How small can we make a magnetic structure and still be able to use it? What is the smallest unit of data storage?”

A bit of data is typically either a 1 or a 0. A hard drive that stores data can use up to 1 million atoms to store each bit, so scaling down the number of atoms used to store data posed an intriguing challenge. They used a form of magnetism called antiferromagnetism, where atoms spin in opposite directions. This allowed them to create an experimental atomic-scale magnet-based memory that is at least 100 times denser than current hard disk drives and solid-state memory chips. Dr. Heinrich's team started with one iron atom on a copper nitrate substrate and used the tip of a scanning tunneling microscope to add atoms until they were able to store 1 byte of data. To store the data, they switched the magnetic information in the bits from a zero to a 1 and back again. They worked at the extremely low temperature of 1 K (272 °C or −458 °F), which allowed them to stabilize the process, build the structure one atom at a time, and eliminate thermal effects [11].

After assembling the single bit of data, they combined 96 atoms to make 1 byte of data (which is used to represent a number or letter in a computer). Next, they used the process to spell entire words – the first word they spelled was the word “Think,” which required 5 bytes of information, or 480 magnetized atoms. In January 2012, Dr. Heinrich told Computerworld, “The ultimate end of Moore's Law is a single atom.”

The month after Dr. Heinrich made his prediction, a group of Australian and American researchers reported that they had created a circuit from a single atom. Researchers from the University of New South Wales, Purdue University, and the University of Melbourne reported in Nature Nanotechnology Letters that they had created a single-atom transistor using a single atom of phosphorus (a single atom of phosphorus is approximately one-tenth of a nanometer across). The atom of phosphorus was positioned in a channel in a silicon crystal. The same team also announced that they created a wire made from phosphorous and silicon, one atom tall × four atoms wide, which exhibited properties of copper wire. To position and functionalize the atom, the researchers had to use temperatures as cold as liquid nitrogen (−391 °F/−196 °C), similar to the IBM team that developed the 12 atom memory storage.

Michelle Simmons, group leader and director of the ARC Centre for Quantum Computation and Communication at the University of New South Wales, noted that the team's single-atom transistor uses the same materials currently used in semiconductors, which makes the process easier to commercialize. She believes their technique is scalable. Professor Simmons credited the many outstanding students and postdoctoral researchers who worked on the pan-Pacific project, and said the process involved numerous systemic studies and “brute determination.”

Gerhard Klimeck, Director of the Network for Computational Nanotechnology at Purdue, said much of their collaborative work was facilitated by use of – an online meeting place and education hub that provides tools to facilitate international collaboration and community building. NanoHUB content is used in over 450 classrooms at more than 150 universities worldwide.

“To me, this is the physical limit of Moore's Law,” said Dr. Klimeck, “We can't make it smaller than this.”2)

Why Is Moore's Law So Important?

At this point, you might be asking, why are we doing this? Why do we need smaller, faster computers? The reality is, we live in an age of big data. We are doing big things that require massive amounts of information, whether we're analyzing customer behavior on billions of Internet transactions, or trying to predict complex weather patterns that involve a myriad of variables. To engineer supercomputers that are greater in power and smaller in size and energy use, we need to develop smaller, more efficient nanocircuits.

To put the big data explosion in perspective, your computer measures its memory capacity in megabytes and terabytes. One byte can typically store one letter or number. Conceptually, 1 MB is approximately 1 million bytes; 1 GB is 1 billion bytes; 1 TB is 1 trillion bytes; 1 PB is 1 quadrillion bytes, and so on – although the actual number is different because 1 kB is actually 1024 bytes, not 1000 bytes – so 1 MB is 1024 × 1024 bytes = 1 048 576 bytes of memory, and so on up the scale.

  • The 2009 movie “Avatar” used more than a petabyte of locally stored data to generate its 3D CGI effects. The massively multiplayer online game, World of Warcraft, needs more than 1.3 PB to manage the game that is played by more than 10 million subscribers worldwide. The human brain can store about 2.5 PB of binary data [12]. Google, the search engine giant, processes about 24 PB of data each day. The NSA – whose data mining activities have generated a fair amount of controversy – says the worldwide Internet carries 1826 PB of information per day. The German Climate Computing Center (DKRZ) has a storage capacity that can accommodate 60 PB of climate data. Facebook accounts for about 100 PB of data. The global daily total use of data is estimated to top 500 PB.

How big will “big data” grow? In 2011, IBM built a 120 PB storage array. In January 2012, the supercomputer pioneer Cray started construction of the Blue Waters Supercomputer, which is reported to have a storage capacity of 500 PB. The world's fastest computer at the end of 2013 was the Tianhe-2 supercomputer at Sun Yat-sen University in Guangzhou, China.

Nanotechnology is racing to keep up with the explosion in big data and the need to store and work with these massive amounts of information. Big data is being driven by broadband video, social media, massively multiplayer online games, RFID inventory tracking, Internet searches, medical recordkeeping, genomic libraries, astronomical applications, e-Commerce transactions, language translation, voice technology, massive open online courses (MOOCs), and a surge in cloud computing – a massive list of massive data apps.

Teradata, a pioneer in database warehouses and analytics, created the first data system over 1 TB in 1992, which was needed by its client Wal-Mart to handle the retailer's enormous transaction load. In 2011, Teradata formed the “Petabyte Club” for its largest data users. The first members were eBay, Wal-Mart Stores, Bank of America, and Dell. eBay, which has 100 million active users globally, and 300 million live listings at any point in time, processes 2 billion page views daily, 250 million search queries, and 75 billion database calls, with total data volume ranging up to 20 PB.

It is ironic that we will need increasingly small nanosized computer circuits to provide the memory and speed needed to process increasingly large arrays of big data, and to extend Moore's Law. We are gaining a sense of how small we can make a computer, but at the other end of the spectrum, we are still trying to figure out how intelligent a computer network can become.

A Computer That Wins TV Game Shows? What Next?

At the edge of the computing universe is the intriguing concept of artificial intelligence, which has been moving inexorably forward since the 1980s. In February 2011, an extremely clever supercomputer named Watson designed by IBM was pitted against two of the most successful winners of the TV game show, Jeopardy. One of the contestants had won 20 times and the other had won 74 games, so the competition was stiff. Watson didn't get all the questions right, but after a 3 day tournament the computer beat the two human champions. Watson demonstrated an ability to understand some very subtle and nuanced questions such as “It's a poor workman who blames these” – to which Watson responded, “What are tools?” Watson won $77 147 (£47 812) and set a new standard for artificial intelligence.

Is Watson the first glimpse of an artificial intelligence android? Migrating Watson's capabilities into an android will require smaller faster circuits to store and process enough knowledge and do the pattern matching required to make “decisions” about what to say and do. Nanosensors will help robots and androids map, understand, and respond to their surroundings. And before these sensors and circuits enable robots, they will enable us humans to extend our reach beyond our grasp.

3.5 Invisibility Cloaks, Optical Tweezers, and Nanophotonics

What do you know about light?

Well, you probably know that light can be visible or invisible, depending on the wavelength (infrared, ultraviolet, etc.). You know that light travels at 186 000 miles/s (300 000 km/s) and moves in a straight line. Light can be absorbed, scattered, reflected, diffused, refracted, and amplified. Light can behave as a wave, but sometimes it acts like a particle. It can also be converted from one form of energy to another, which is how we get solar energy, for example. Light is measured in photons (discreet bundles of electromagnetic/light energy) or lumens (how much illumination a source of light provides).

Visible light has a wavelength that ranges from ∼400 to 700 nm (some sources say the range is 380–760 nm). The approximate wavelengths for different colors are violet (400 nm), indigo (445 nm), blue (475 nm), green (510 nm), yellow (570 nm), orange (590 nm), and red (650 nm) (source: Atmospheric Science Data Center, NASA). These colors can vary somewhat. For example, the yellow light generated by a sodium vapor streetlight has a wavelength of 589 nm. Ultraviolet light can vary from 10 to 400 nm. The wavelength for a traditional ultraviolet “black light” you might see in an aquarium or a night club is 365–400 nm. Infrared light can range from 700 nm to 300 µm.

A small and extremely talented community of optical physicists are working very hard to develop techniques to slow, trap, manipulate, and even “stop” light, which is creating the foundation for a new generation of optical devices, including optical nanomaterials and optical computers that enable light to be captured, manipulated, modified, and stored.

Some of this groundbreaking research is being done at Dr. Marko Loncar's Laboratory for Nanoscale Optics, at the Harvard School of Engineering and Applied Sciences.3) To design the next generation of optical chips, Dr. Loncar's group is exploring applications for hybrid active nanophotonic devices, including metallic nanostructures (surface Plasmon-based approach), photonic crystal cavities, and metamaterials. This research has important implications for photovoltaics, photochromatic materials, photocatalysts, photoresponsive gels, and optical computing in general.

It is only a matter of time until we see affordable optical computer systems. One intriguing question is: If we design optical computer systems, including robots and weapons systems, will we also be able to make them optically invisible?

How to Design an Invisibility Cloak and Move Objects with Light

Invisibility has been part of our popular culture since H.G. Wells wrote “The Invisible Man” in 1897, and is the subject of countless movies and television shows. The aliens in the Predator films wear combat suits with an invisibility cloaking feature that makes them look like images from a pixilated video game. More recently, J.K. Rowling's heroic character Harry Potter wore an invisibility cloak made from the hair of a magical creature called a Demiguise. Perhaps the hair of the Demiguise was nanoscale hair, thinner than the wavelength of visible light.

In the military, stealth bombers and naval ships use special materials and construction methods to achieve “invisibility” from enemy radar and missile systems. Of course, it is one thing to conceal something from radar, and quite another to hide something from the human eye. For many years, the technology to make something optically invisible existed only in science fiction. However, science fiction has a habit of morphing into science reality, and so it is with invisibility cloaks.

In recent years, science has begun to accept the notion that invisibility cloaks are something we can actually design. Also, researchers have demonstrated several ways to create “invisibility.” One way is to use a network of cameras and projectors – essentially, to shoot a video of what is behind an object, and project that image on the front of the object, to make it appear to be invisible. Some researchers are creating “invisibility” by using optical nanomaterials to induce light to essentially follow a trail of nanoparticles around the cloaked object.

Another approach is to place a crystal in front of the object and refract light in a way that makes an object disappear – similar to how magicians use mirrors to make objects disappear in a Las Vegas stage act. Ironically, mirrors made of metamaterials have been used to bend light and other types of electromagnetic waves to achieve a form of invisibility – a nanoinnovation that gives new meaning to the phrase “smoke and mirrors.”

The Nanophotonics Group led by Michal Lipson (Figure 3.5) at Cornell University in Ithaca, New York, has demonstrated how to hide an object in the “bulge” of a mirrored surface that uses light-bending metamaterials (which are actually nanomaterials) to configure the mirror so that it appears that the surface is flat and the bulge does not exist.

Figure 3.5 Dr. Michal Lipson at Cornell heads one of the world's top nanophotonics research teams (Cornell University photo by Jason Koski).

A cloak using nanostructured silicon has been developed by a research team led by Xiang Zhang, a principal investigator with Berkeley Lab's Materials Sciences Division and Director of UC-Berkeley's Nanoscale Science and Engineering Center.

Collaborative teams at the University California, San Diego, Duke University, and ETRI in South Korea have demonstrated that it is possible to control the speed and direction of light using memory metamaterials whose properties can be selectively and repeatedly changed, which enables metamaterials to be tuned. This innovation is an important step toward enabling the manufacture of Gradient Index of Refraction (GRIN) devices [13].

Other researchers have used crystals to cloak objects. Baile Zhang and his colleagues at the Singapore-MIT Alliance for Research and Technology (SMART) center in Singapore have used calcite crystal to shield a 38 mm long steel wedge from visible light underwater, which may be useful for shielding submarines and installations on the floor of the ocean. Collaborators Shuang Zhang at the University of Birmingham and Sir John Pendry from Imperial College in London have demonstrated a calcite cloak that works in air.

Janos Perczel, a Hungarian undergraduate student studying at the University of St. Andrews under the guidance of Professor Ulf Leonhardt, has used an optical device called an “invisible sphere” to slow light as it approaches an invisibility cloak. Perczel calls his technique “partial transmutation.” This innovation could enable the wearer of an invisibility cloak to remain invisible while in motion, across a larger range of colors in the visible spectrum, and to move around against different types of backgrounds [14]. It is interesting to note that St. Andrews, which is located in Fife, Scotland, is the third oldest university in the English-speaking world, founded in 1413.

Janos Perczel's innovation is an intriguing example of how researchers are turning science fiction into science reality. In 1967, an award-winning Belfast science fiction writer named Robert Shaw (1931–1996) wrote a short story called “Light of Other Days” that introduced the concept of “slow glass” through which the past could be viewed. Many innovations that are now being enabled by nanotechnology, such as artificial blood cells, swarms of nanosensors – and invisibility cloaks – were first envisioned by science fiction authors and film makers.

Many of the cloaks we read about in science journals use light-bending or light-slowing metamaterials (e.g., man-made nanomaterials) and transformative optics to conceal an object from an observer. Most of the cloaking technologies reported by scientists involve a proof of concept using objects that are only a few microns or millimeters in size. Scaling up to cloak a human, a structure or a vehicle will require a lot more research. The first commercial invisibility cloak will probably be made from configurable nanomaterials that change shape or refractability. This will require a way to manufacture large-scale matrices or “cloaks” made of metamaterials. The current method used to create metamaterials – electron-beam lithography – is expensive and time-consuming.

A group led by John Rogers, a professor of materials science and engineering at the University of Illinois at Urbana-Champaign, has developed a way to “print” sheets of metamaterial that resemble a matrix or fishnet pattern. The group has produced sheets a few square inches in size, and is working to scale up their process to several square feet. Being able to produce metamaterials on a large scale will not only support the development of invisibility cloaks but will also facilitate the development of superlenses, night-vision invisibility cloaks, and more.

In May 2012, a research group from Towson University and the University of Maryland, led by Dr. Vera Smolyaninova, announced the development of an array of 25 000 tiny invisibility cloaks with the capability of “trapping a rainbow” of light. Dr. Smolyaninova says that this innovation could lead to the development of “spectroscopy on-a-chip,” which could examine fluorescence at thousands of points simultaneously. This capability has special applications in biochips and biosensors. Arrays of sensors are an important innovation, since they provide the type of parallel processing that will lead to such capabilities as being able to test for multiple genetic conditions in a DNA sample. This array was also demonstrated to have light-slowing properties and may provide a method to test other types of invisibility cloaks. To create their array, the researchers used commercially available microlenses in combination with a thin gold plating. This first-of-a-kind innovation was reported in the Institute of Physics and German Physical Society's New Journal of Physics [15].

Some of the most impressive advances in the design of invisibility cloaks are coming from the relatively new fields of nanophotonics and transformation optics.

The Nanophotonics Group at Cornell University is a great example of how optics researchers are pushing the technology envelope to create innovative technologies that were previously impossible. The group is investigating the physics and applications of nanoscale photonic structures, focusing on light-confining structures that can slow, trap, enhance, and manipulate light.

Dr. Lipson has received considerable media recognition for her team's research on optical cloaking. Her team has demonstrated several designs for an optical cloak that uses nanometer scale dielectric structures to conceal an object under a mirrored surface. The technique involves using transformative optics to reshape the surface of a reflective “carpet” so a bulge or deformation in the surface appears to be smooth to an external observer. This allows objects to be hidden under the deformation without revealing their existence. The device is designed to operate at all angles. According to the team's research paper, these results represent the first experimental demonstration of an invisibility cloaking device at optical frequencies. This research shows how the trajectory of light can be manipulated around a region, and has applications in defense, communications, and other industries [16]. The team also suggests that the process can be reversed to concentrate light in an area, which has applications for efficiently concentrating sunlight in solar energy applications.

Dr. Lipson's research involves innovations that not only bend light but also bend and twist some of the conventional notions of how light has been traditionally thought to behave. She is one of the few physicists in the world who has developed a method to trap and slow light. Her technique involves trapping light in a circular tube, then quickly shutting the gate where the light entered (so it doesn't leak back out) – and reopening the gate. The light loses energy the longer it stays in the trapping device and may need to be intensified after it leaves the device. This type of research has important implications for the development of ultrahigh-speed optical computers and optical switches in broadband telecom systems.

The Cornell group has also used particles of light to move nanoscale objects. That's another thing you probably didn't know about light. At human scale, particles of light from the sun are not strong enough to move objects, but at the nanoscale, particles of light can actually cause nanoscale objects to move, suggesting that light can be used to turn nanoswitches on or off in nanoscale computer chips. Increasingly, scientists are predicting that nanophotonics will soon replace microelectronics in communication and information processing systems.

“Nanophotonics can be used to make things visible as well as invisible,” Dr. Lipson explains. She is currently working on a method to use transformative optics and metamaterials to provide a novel solution for some forms of blindness. She noted that this research is very preliminary and the technology is complex, but ultimately achievable.

In 2010, Dr. Lipson was awarded the $500 000 MacArthur Award, one of the most prestigious awards in science, which is sometimes called the “genius” award.

3.6 Nanoscience Wild Cards: Will Tree Lights Replace Streetlights?

In addition to the achievements described here, there are a host of “wild card” innovations that result from unexpected or accidental discoveries. In the field of nanoscience, these serendipitous discoveries are occurring at an unprecedented pace. It is not unusual for a researcher studying a material or process to stumble on a concept or idea that leads to an entirely new innovation.

It is also possible to incentivize the development of wild card innovations through competitions and calls for papers or proposals. In one notable example (see later), MIT has provided a library of biological parts, a competition, and toolkits to promote the development of innovative solutions.

An Accidental Discovery Turns Trees into Lights

A great example of a wild card innovation is the accidental discovery made by Taiwanese researchers who are working on a method for replacing streetlights with trees by implanting their leaves with gold nanoparticles that cause them to glow red – an elegant solution that could provide natural “tree light,” which would be especially applicable in rural areas of the world.

Dr. Yen-Hsun Su is a postdoctorate scientist in the Research Center for Applied Science (RCAS) at Academica Sinica in Taiwan. He received his doctorate from the Department of Physics at National Cheng Kung University in Taiwan where he was supervised by professors Wei-Min Zhang and Shih-Hui Chang. Dr. Su and his colleagues were looking for a way to create high-efficiency LED lighting without using toxic chemicals like phosphor powder. In the process of this research, Dr. Su made a remarkable discovery. He found that on injecting gold nanoparticles into the leaves of the Bacopa caroliniana plant and exposing them to ultraviolet light, his team was able to induce the chlorophyll in the leaves to produce a reddish glow [17]. Dr. Su is credited with the seminal discovery that gold nanoparticles can induce luminescence in leaves.

This discovery has led to an entirely new course of scientific investigation, to develop what Dr. Su calls “Bio-LED” luminescence, which could be used to induce trees and other plants to emit a luminescent glow strong enough to illuminate streets and roads at night. Dr. Su has observed that this technology could save energy and even absorb CO2 since the Bio-LED luminescence causes the chloroplasts in trees and plants to conduct photosynthesis, which absorbs CO2 and produces oxygen.

The notion of using “glowing trees” instead of streetlights raises some interesting possibilities for future research. Imagine the benefits of being able to use “glowing trees” instead of streetlights, especially in rural areas of the world where there is no electricity, or in countries where electricity is too expensive or unavailable.

While some critics have observed that it sounds inefficient to shine ultraviolet light on the trees to induce them to glow, or that using gold nanoparticles would be expensive; the real value of this discovery comes from the concept of using bioluminescent trees to light streets and roads. It is easy to imagine how glowing tree-light will one day supplement electrical streetlights. Over time, more efficient methods are certain to be developed. There are other ways to make trees “glow.” For example, one method might involve genetic engineering, using luminescent genes.

iGEM: How Student Nanoinnovators Are Lighting Up the World

Not all nanoinnovators are Ph.D. scientists. Many are students who develop an interest in some aspect of nanoinnovation and wind up creating something really special. Some of the most impressive student achievements have been developed for the International Genetically Engineered Machine Jamboree competition (iGEM) hosted at the Massachusetts Institute of Technology (MIT).

iGEM is the world's premiere synthetic biology competition. iGEM invites student teams to draw from a library of several thousand standard biological parts called “BioBricks.” Goals of the BioBricks project include standardizing and automating the development of nanotechnology innovations using standardized biological parts. BioBrick™ parts were originally introduced in 2003 by Tom Knight at MIT. Drew Endy (now at Stanford) and Christopher Voigt at UCSF also participated in developing the project. Randy Rettberg currently maintains the BioBrick registry, which includes several thousand public domain parts that can be viewed online at Student teams may also develop their own BioBrick parts as part of their research. This initiative is an ambitious open source effort to help foster safe, ethical development of technology solutions using synthetic biology.

Undergraduate student teams from the Americas, Europe, and Asia work at their own schools over the summer, using biological parts from the Registry of Standard Biological Parts to build biological systems and operate them in living cells. Examples of the student achievements range from an arsenic biodetector to a cost-effective red blood cell substitute. Student teams have participated from Australia, Belgium, Brazil, Canada, China, Colombia, the Congo, Denmark, France, Germany, Hungary, India, Italy, Japan, Kenya, Korea, the Mexico, the Netherlands, Panama, Poland, Scotland, Singapore, Slovenia, South Africa, Spain, Sweden, Switzerland, Taiwan, Turkey, and the United States.

In 2009, a team of nine undergraduate students at Cambridge University won the Grand Prize with an innovation they call “LuxBrick.” The students used genetic material from fireflies and a luminescent marine bacterium (Vibrio fischeri) to boost the intensity and activity of light-emitting enzymes. They developed a bacterial culture about the size of a bottle of wine that generated light – in different colors – that was bright enough to read by. The accompanying pictures show one of the students reading The Jungle Book by Rudyard Kipling, using the light from the LuxBrick bacteriological bubble lamp (Figure 3.6) and the other photo shows two of the team members holding flasks of bioluminescent material (Figure 3.7).

Figure 3.6 Ben Reeve reads The Jungle Book by Rudyard Kipling by the light of the Cambridge research team's bioluminescent lamp (photo courtesy of Ben Reeve and the Cambridge iGEM team).

Figure 3.7 Cambridge students Ben Reeve and Theo Sanderson illuminate their faces using flasks of bioluminescent material (photo courtesy of Ben Reeve and the Cambridge iGEM team).

The students on the 2009 Cambridge team included Anja Hohmann, Ben Reeve, Bill Collins, Emily Knott, Hannah Copley, Paul Masset, Peter Emmrich, Theo Sanderson, and Will Handley. The diversity of the group is remarkable – each student represents a different discipline. Anja is a biochemist, Ben is a molecular biologist (and the team's “Hacky Sack-master), Bill is a control engineer, Emily is a mechanical engineer, Hannah is a medic, Paul is a systems engineer, Peter is a plant scientist, Theo is a geneticist, and Will is a physicist.

This diversity helped them tackle some of the tricky problems associated with bioluminescent technology. One of the problems with bioluminescence is what happens to the light-emitting compounds after they “glow.” Luciferins are compounds that emit light but after the light is generated, the compounds are converted to oxyluciferin, which cannot produce light. The Cambridge students developed a way to recycle oxyluciferin, to maintain the “glow.” Their biochemical lights were engineered to produce a variety of colors. Techniques for causing the bacteria to “hibernate” until needed have also been proposed by the team. The students are currently exploring how to apply their discoveries to create bioluminescent streetlights to replace conventional street lamps.

“BioBricks are standardized biological parts,” explained Ben Reeve. “One of the BioBricks we produced was the LuxBrick. We used this part to produce both the bubble lamp and fire exit sign” (Figure 3.8) ( Their “LuxBric” bacterial bubble lamp, illuminated fire exit sign, and simulation of bioluminescent street lamps can be found at their Web site ( How the LuxBrick was designed is also described in detail on their site (

Figure 3.8 A standard fire exit sign (a) and the same sign illuminated by bioluminescence (b) (photo courtesy of the Cambridge iGEM team).

One interesting aspect of bio-lights is that they have to be “fed” in some way, on a regular basis, which means that bio-lights may need fertilizer or other nutrients in lieu of electricity, to keep operating. Imagine the paradigm shift that would be if we go from powering lights with electricity to powering lights with fertilizer!

This stream of research holds the potential for a range of innovations. For example, in addition to tree lights replacing streetlights or garden lights, it is easy to envision new types of Christmas trees that glow in the dark, or even change colors biologically. Perhaps trees will be engineered to serve as biological sensors or indicators. Imagine trees or crops glowing when they need water, so they can be irrigated only when needed.

The popular iGEM competition keeps growing – the competition started with a handful of teams in 2005 and increased to 130 teams in 2010. An interesting side note to the iGEM competition is that the top two teams in 2010 were from Slovenia and Peking, which illustrates the global nature of nanoinnovation. Student teams from Slovenia won the iGEM grand prize in 2006, 2008, and 2010.

There are similar student contests and initiatives in virtually every country. A few examples include in2nano (Egypt); the MEMSIC Cup/International Contest of Applications in Nano-micro Technology (iCAN/14 countries); Time for Nano Video Contest (EU); and the Khwarizmi Youth Award Competition (Iran). Many universities hold their own nanotechnology events and contests. A good example is the annual NanoDay sponsored by the Nano/Bio Interface Center at the University of Pennsylvania, which invites Penn students and high school students to “imagine the world at the nanoscale.”

Giving Students Access to Nanotechnology Systems

Scanning probe microscopes and other instruments are not yet available to secondary (high) schools, which means that most students need to wait until they enter college to start working with nanotechnology. Fortunately, a growing number of forward-thinking high school teachers are finding ways to teach nanotechnology to their students.

A great example is Mike Boyer, an engineering teacher in the technology and engineering education department at North Penn High School in Lansdale, Pennsylvania. He teaches nanotechnology as part of a program he launched in 2005 called The Future is NEAR (NEAR stands for “Nanotechnology Education and Research”) [18].

“The first year I ran the program,” he recalls, “we had three teams. At the end of our first year, the students begged to take a presentation on the road to other schools although they were graduating in a few weeks and going off to universities. They wanted other schools to see what could be accomplished.”

“Over the years, the student research projects picked up in complexity. I found myself getting farther out of my comfort zone and at the same time the student teams were learning, setting goals, assessing their progress, assessing their Gantt charts and comparing notes with other teams, which challenged me as a facilitator. I've spent many late nights after my family went to bed, researching team projects so I could help guide them, which is important because the field of nanotechnology is constantly growing and our knowledge keeps expanding.”

“Because we do not have a scanning electron microscope in class,” Mr. Boyer explains, “we collaborate with Drexel University to provide a field trip where our students can run their experiments in the nanotechnology laboratory. This has been an invaluable collaboration. Until the field trip, the students need to work blindly and have to make educated guesses regarding the results of their experiments. They study the results of similar experiments in scientific journals to prepare as much as they can before their field trip. Sometimes the experiments don't work in the first trial, which makes it more difficult to coordinate access and continue the experiments. This is much less hands-on than we would like, but it's difficult to get funding for a $70 000 SEM for one high school, or even a group of schools. Recently, I was able to arrange to get a Hitachi SEM on loan for a week from Angstrom Scientific. One day I hope to have an SEM for my students!”

The list of team projects conducted by Mr. Boyer's nanotechnology class is impressive: portable electrospinning device, electrospinning envelope cone analysis, magnetic polymer fibers, studies of the effects of solvents on nanofiber production, hydrophobic nanofabrics, liquid armor, drug and particle encapsulation in nanobeads, photovoltaic polymers, piezoelectric nanofibers, photochromatic and thermochromic nanofabrics, and the use of bamboo in the creation of antibacterial fabrics. It is remarkable and impressive that such sophisticated experiments are being studied by teams of high school students. Imagine what could be accomplished if all the high schools in the world had nanotechnology programs. Most important, these projects and experiments energize the students to pursue careers in nanotechnology. Many of Mr. Boyer's students have received research positions after graduating high school, and many go on to continue their nanotech research in college (Figures 3.9 and 3.10).

Figures 3.9 Students from North Penn High School in Lansdale, Pennsylvania formulate their experiments at school and then complete them using the nanotechnology systems provided by Drexel University in Philadelphia. The technology-oriented high school provides this opportunity under the N.E.A.R. program developed by engineering teacher Michael Boyer. This collaboration is an excellent example of how resourceful teachers and students are finding way to gain access to expensive nanoimaging systems (photos courtesy of Michael Boyer).

Figures 3.10 High school students in the N.E.A.R. program have a unique opportunity to gain hands-on experience using sophisticated nanotechnology instruments in a university laboratory.

Youth camps and outreach programs that include nanotechnology are being sponsored by government agencies and companies in many countries. Some notable examples include the in2nano program in Egypt and the in2nanotech mentoring program offered by La Trobe University in Australia – similar programs are underway in countries as diverse as Russia, India, and Iran.

James McGonigle, Director of Education and Outreach at the University of Pennsylvania's Nano/Bio Interface Center, discussed the need for more affordable nanoimaging systems for high schools: “For nanoscale science and engineering to really take hold and capture the imagination of pre-college students, we need affordable ways for high school students to experience the authentic process of working at the nanoscale. Students need to be able to be able to synthesize nanoscopic materials in their high school labs and be able to ‘see’ the materials first hand. Affordable imaging systems that cost thousands of dollars – not tens of thousands – would allow schools and school districts to provide sophisticated and authentic experience on tools that the 21st century technology workforce will use. Solutions might include a simple AFM that is robust enough to travel between classrooms and between schools so many teachers can share the resource.”

“More curriculum resources and laboratory activities are needed to prepare students to the enter the nanotechnology workforce of the future. The Nano/Bio Interface Center at the University of Pennsylvania and the A.J. Drexel Nanotechnology Institute have worked together to provide over 100 teachers with summer research experiences in nanoscale science and engineering. This experience translates directly into classroom lessons for their students, helps prepare teachers to work with students when they visit university labs, and paves the way for the future when school districts will have access to their own nanotechnology instruments.”

3.7 Science Genius versus Commercial Challenge

Translating scientific prowess into commercial success poses a special challenge for nanoinnovators. While it is true that most of the first wave of nanoinnovations came from university research labs, it is also true that many of these commercial ventures have stumbled or failed.

In business, someone who launches and leads several successful business ventures is called a “serial entrepreneur.” Someone who develops a string of nanoinnovations can be called a serial nanoinnovator. One of the best examples of a serial nanoinnovator is Chad Mirkin, Director of the Nanoscale Science & Engineering Center and the International Institute for Nanotechnology at Northwestern University and Rathmann Professor of Chemistry (Figure 3.11). Chad leads a group of 50 researchers that have developed numerous nanoinnovations, including nanoparticle-based biodetection schemes, Dip-Pen Nanolithography, and innovations involving supramolecular chemistry, nanoelectronics, nanooptics, and medical diagnostics.

Figure 3.11 Professor Chad Mirkin, Director of the International Institute for Nanotechnology at Northwestern University (photo by Bill Arsenault).

As a nanoinnovator, Dr. Mirkin is a standout by any standard. He is a world-renowned chemist and nanoscience pioneer, the author of more than 450 manuscripts and over 380 patents and applications. He has been the most cited chemist in the world for the past 2 years and the top-cited nanomedicine researcher, and has been called the world's most-cited nanoscientist. His seminal papers, “A DNA-based method for rationally assembling nanoparticles into macroscopic materials” (Nature, 1996) and “Selective colorimetric detection of polynucleotides based on the distance-dependence optical properties of gold nanoparticles” (Science, 1997) have both been cited more than 2000 times – contributing to a total of more than 40 000 citations for his published papers. He is the recipient of over 70 national and international awards, including the $500 000 Lemelson-MIT Prize (June 2009), the first NIH Pioneer Award, and the Feynman prize for experimental breakthroughs in nanotechnology (2004), and the American Chemistry Society's Award for Creative Invention (2012). Chad serves on President Barack Obama's Council of Advisors for Science and Technology. He gives 50–70 lectures a year and is constantly in motion, racing to fit as many innovations as possible into one frenetic lifetime.

Dr. Mirkin is the founder of three companies – Nanosphere, NanoInk, and Aurasense – which were some of the earliest and most promising ventures in the field of nanoinnovation. These ventures include both successes and failures, and provide interesting insights for nanoinnovators who want to develop their own ventures and commercial projects.

The Rise and Fall of NanoInk

More than a decade ago, Chad Mirkin recognized the need for a more practical approach to nanolithography. Dr. Mirkin and his research group at Northwestern University determined that under the appropriate conditions, molecules rather than energy could be transferred to a wide variety of surfaces to create stable chemically adsorbed monolayers. Their patented lithographic process used atomic force microscope tips as writing tools and diffusible material for ink. They called the process Dip Pen Nanolithography (DPN) [19]. The general process is called polymer pen lithography (PPL). PPL is primarily a fabrication tool, while DPN is used as both a fabrication and an imaging tool.

Their patented process uses an array of millions of polymeric pens that create nanoscale architectures by “drawing” molecules onto a substrate over large areas with extreme precision. The pens are attached to the moving arm of a scanning probe microscope, which traces the designs. As the tips are pressed down on the substrate, the tip is flattened and a larger feature is generated. Different types of substrates, materials, and molecular inks can be used.

In 2001, Dr. Mirkin founded a venture called NanoInk, Inc. to commercialize the technology. Unfortunately, the venture did not fulfill its early promise. In 11 years, NanoInk absorbed more than $150 million in investment capital, which came mostly from Lurie Investments, a Chicago-based investment fund managed by philanthropist Ann Lurie. In 2013, Ms. Lurie withdrew as the company's sole funding source. NanoInk filed Chapter 7 bankruptcy in April 2013 and began liquidating assets – drawing a curtain on one of the very first nanotechnology ventures. This venture had extremely high expectations and was a darling of the press and the nanotech community. With a huge patent portfolio and proven technology, few people expected NanoInk to fail.

At the time of its bankruptcy, NanoInk's assets included 60 US patents, 74 US patent applications, 97 foreign patents, and 230 foreign patent applications. Obviously, the size of a nanoventure's patent portfolio is not always a good indicator of long-term commercial success. In May 2013, a bid process was established and companies interested in purchasing NanoInk's patents were invited to bid on the portfolio.

So how did this venerable nanotech pioneer come to such a sudden end? One observer suggested that NanoInk failed because they were chasing “technology push” rather than “market pull.” Tim Harper, CEO of Cientifica, likened NanoInk's dip-pen technology to “replacing the printing press with a bunch of monks.” Harper added that “illuminated manuscripts can look good but if you can't mass-produce things there isn't a business [20].” The company's technology used massive arrays of dip pens to “paint” or “draw” nanoscale ink on a substrate, but had trouble finding viable commercial applications for the technology.

Dr. Mirkin has indicated that he had not been active with the company for several years before it failed, having moved on to other scientific projects and ventures. By most accounts, the failure of the company was attributed to the management team, not the scientific team, driven by a lack of commercial markets and applications and overspending.


Dr. Mirkin is also the inventor of an innovative bioscience technology based on the Verigene® System, an FDA-cleared molecular diagnostics workstation that utilizes patented gold nanoparticle technology to detect nucleic acid and protein targets of interest for a variety of applications. This technology was commercialized through Nanosphere, a public company founded in 1999 by Dr. Mirkin and his Northwestern University colleague Dr. Robert Letsinger. Nanosphere is also an example of how expensive it can be to start and maintain a nanoventure. Nanosphere more than doubled its revenues, to more than $5 million in 2012, but struggled to make a profit. Nanosphere lost an average of $40 million per year since its inception and lost $32.9 million in 2012. By 2013, the company was valued at less than half of its invested capital. In February 2013, Nanosphere's CEO was replaced and in May, Dr. Mirkin left Nanosphere's board. For the fiscal year ended December 31, 2013, Nanosphere reported that revenues nearly doubled from $5.1 million to $10 million, but recorded a net loss of $34.6 million. In January 2014, Nanosphere received FDA approval to market its Verigene in vitro diagnostic test for identifying Gram-negative bacteria associated with bloodstream infections. The company's management team expressed confidence and expected revenues to nearly double in 2014.


Dr. Mirkin and his Northwestern University colleague Shad Thaxton formed a venture called “Aurasense” in 2009, to develop nanoparticles for use as therapeutics and intra-cellular biomolecule detection probes. This venture is working to turn gene-regulating nanoparticles into commercial products. The venture is based on scientific developments at Northwestern and continues the process of invention, innovation, and commercialization that Chad Mirkin and his research associates have embarked on, and where they continue to persevere as they work to overcome challenges and setbacks to turn remarkable science into viable commercial ventures.

3.8 Nanoscience Pioneers Are Mapping the Future

Many of the greatest scientific breakthroughs in nanotechnology have come from IBM, which learned to “think small” many decades ago when IBM scientists created the first scanning tunneling microscopes.

IBM scientists have a sense of whimsy – their first nanoscale image was an IBM logo created by manipulating individual atoms. In recent years, IBM has used nanotechnology to create the smallest map of the world, and the world's smallest cartoon animation. IBM's map is the smallest 3D map of the world. It was created using nanoscale tools, structures, and techniques (see Figure 3.12). This map is so small, it can fit in a grain of salt!

Figure 3.12 To illustrate a breakthrough nanotip-based patterning technique, IBM scientists created the world's smallest 3D map. The device used to create this map is small enough to fit on a tabletop and is accurate to 15 nm or less (photo courtesy of IBM Zurich Research).

In May 2013, a group of IBM scientists announced that they had created the world's smallest movie, a feat that was verified by Guinness World Records. The film cartoon, entitled “A Boy and His Atom” (Figure 3.13) used a scanning tunneling microscope with a supersharp needle to arrange carbon monoxide molecules on a copper surface to create a 45 × 25 nm2 picture of a boy playing with a single molecule. The individual molecules were moved and reimaged for each frame to produce 242 frames. The cartoon is accompanied by a catchy tune. Andreas Heinrich, the principal investigator at IBM Research, said: “This movie is a fun way to open a dialogue with students and others on the new frontiers of math and science.”

Figure 3.13 These scenes are from the world's smallest movie, produced by IBM researchers and entitled “A Boy and His Atom” (image courtesy of IBM Research).

The group also wanted to focus attention on their initiative to determine the smallest number of atoms it takes to reliably store one bit of magnetic information, which they claim is 12 atoms. This compares to the approximately 1 million atoms it currently takes to store 1 bit of data in a computer or electronic device. According to Dr. Heinrich, the same approach used to create the world's smallest movie is being used to create new computing architectures. One day, he predicts, atomic memory could store all of the movies ever made in a device the size of a fingernail.

The nanoscience innovations described in this chapter are only a few examples of the thousands of nanoinnovators who are pushing the frontiers of nanoscience and redefining what's possible. Many of these scientists work tirelessly with no recognition or publicity, to unlock the complex secrets of the nanoscale world. We owe them a huge debt of gratitude for their dedication, commitment, and perseverance.



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