Nano 101

Nano 101

Tiny titans – the future is nano

By Patricia Bow, University of Waterloo Magazine

Nanotechnology. It’s so hot it sizzles. Even distinguished scientists discussing the potential impact of this new technology sound like excited children on Christmas morning.

"Nanotechnology has given us the tools to play with the ultimate toy box of nature–atoms and molecules," says Nobel laureate Horst Stormer.

Any new, powerful technology is bound to stir up a storm of words. Nanotechnology has unleashed a hurricane. It’s been called the next industrial revolution, a "disruptive" technology that will replace or change all other technologies.

The more conservative predictions mention swifter and safer drug delivery, cheaper and more abundant energy, a cleaner environment, and more powerful computers. The more visionary describe a coming utopia, with nature firmly under the human heel, free of disease, poverty, pollution, and old age. The flip side, of course, is a vision of dystopia: ruined economies, invisible monitors everywhere, and rogue nanobots eating up the biosphere.

In a subject so highly hyped, where is truth? How will nanotechnology really affect our lives?

First, a nano primer. “Nano”, Greek for dwarf, means one-billionth of anything. Nanotechnology is the engineering of matter at the scale between one nanometre (a billionth of a metre) and 100 or so nanometres. Now that’s small. Ten hydrogen atoms in a row span one nanometre, a strand of DNA is about two nanometres wide, a red blood cell is some 7,000 nanometres across and a fine human hair measures roughly 80,000 nanometres in diameter.

The dream of nanotechnology is to build things the way nature does, atom by atom and molecule by molecule. Since a molecule’s structure is the key to its properties, we could create any material we please. Take carbon nanotubes. These tubes—formed of one layer of carbon atoms—are 100 times stronger than steel and six times lighter. Depending on how the atoms are aligned, they are more conductive than copper or a better insulator than diamond. They will be a key ingredient in stronger, lighter car bodies and spacecraft; sieves to filter bacteria from drinking water; and the tiniest transistors.

Small means powerful. Why? The smaller the object, the higher its surface-to-volume ratio. Some chemical reactions take place between surfaces, so a material made of nanoparticles will be far more reactive than the same amount of the same material made of larger particles. The outcome will be more powerful catalysts and more sensitive sensors.

Quantum effects also kick in at this scale. Quantum dots, for example, are semiconductor nanoparticles that emit or absorb different wavelengths of light, depending on their size. They could turn up as tiny solar cells dispensed in spray cans, or as biomarkers to track cells through the body.

Information technology has driven many of the advances in nanotechnology. Computer chips and transistors have been shrinking for decades, in the quest to pack in more computing power. For example, transistors now exist that are made of a single carbon nanotube, so small they are invisible to the unaided eye.

Nano-scale innovations are constantly coming down the pipe. It’s no stretch to anticipate computer monitors you could roll up and stick in your backpack, jogging suits with built- in blood pressure monitors, and “nano-vehicles” programmed to deliver drugs to cancer cells only and spare healthy tissues. Within a few years, labs-on-a-chip will replace costly, energy-hungry, massive machines, revolutionizing everything from the way we respond to environmental accidents to the way we test for diabetes.

Is there a down side? In nanotechnology’s early days, many scientists and engineers were too enchanted by its promise to spend much time pondering the social, economic, and ethical implications of their work. That has changed. Some researchers are investigating concerns such as the behaviour of carbon nanotubes and nanoparticles in the body. National scientific bodies are discussing regulations and beginning to fund risk research. Nanotechnology engineering students find discussion of ethics and other issues built into the curriculum.

Arguably, the hype around nanotechnology has been useful. It has created a forum for society as a whole—not just engineers and scientists—to debate the issues. One problem in such a debate is that nanotechnology is not one, but many technologies, and it is still a very young discipline, making any unintended effects hard to predict.

If we plan to debate these questions, we’d better not wait much longer. Nanotechnology is already sending waves through the economy. The National Science Foundation estimates that by 2015, the worldwide market for nano-related products will reach $1 trillion (U.S.). In Asia, Europe, and North America, governments are pouring nearly $5 billion (U.S.) annually into research and development. Nano-based companies are springing up—more than 1,200 worldwide in 2005 alone.

Nanotechnology is flexing its muscles now. If it takes hold the way personal computer technology did in the late 1980s, tomorrow’s world will look very different from today’s.

Ready or not, here it comes.