From small to big

Here’s the situation: you went out partying, next morning you slept right through your alarm clock. You quickly down a special pill that monitors your body during the day and sends the data directly to the server at your GP’s practice. To make matters worse, it starts raining... never mind, the nanoparticles on your coat repel the raindrops and ensure that you stay absolutely dry. Good thing that the sun shone so abundantly yesterday; your iPod’s fully charged thanks to the solar cells in your coat. Not that it would have mattered... you can always listen to music through the tiny speakers incorporated in it. With one finger you lift your shiny ultralight racing bike with nano coating (a mix of carbon fibres and carbon nanotubes) out of the bike shed. And then race quickly to school...

How small is 'nano'?

In the 1965 science fiction film ‘The Strange Voyage’, the idea of robots travelling through a human body sounded like nonsense. Today, thanks to the rise of nanotechnology, almost anything seems possible. But what order of magnitude is ‘nano’? The 1977 film ‘Powers of Ten’ by Charles and Ray Eames starts with a picnic in Chicago. The first shot is one metre square and then it slowly zooms out to an image of ten metres across (10¹ m), one hundred metres (10² m) and further, and further... The camera then zooms in again on the milky way, the solar system, the earth, the park, the picnic, a man’s hand, the skin, the cells, the cell nucleus, the DNA and on to the neutrons and quarks at a scale of 10^-18 m. We are only little dwarves in this ‘everything’; most of it is too small or too huge to be observed with our eyes...

Research in Groningen

Nano, unsurprisingly, means ‘dwarf’ in Greek. Via metres, decimetres, centimetres, millimetres and micrometres, you eventually arrive at a billionth of a metre, or 0.000000001 metres: a nanometre. Nano scientists like Ben Feringa and Bert Poolman study, manipulate and build nano devices using the smallest particles feasible at this super-micro level, molecules and atoms of between 1 and 100 nanometres in size, as if they were playing with LEGO – only with LEGO blocks some 80,000 times smaller than the diameter of a human hair! Eek Huisman, scientist and expert on nano devices, knows all about quantum effects: in the Science LinX Quantum Conducting Device you can experience the extraordinary behaviour of the tiniest particles. The challenge is to use the unusual behaviour of these particles to your advantage. Scientists are also inspired by the exemplary structures created by mother nature, such as the DNA in cells. Feringa and his team succeeded in building the first light-powered molecular motor, neatly anchored to a small bead of gold, working rather like a ship’s screw to transport elementary particles to appropriate body parts or pump liquids through channels...

Special microscopes

These nano technologists use various ‘tools’ to examine matter that is invisible to us, with the aim of pinpointing individual atoms and molecules. Using TEM (Transmission Electron Microscopy) and SPM (Scanning Probe Microscopy) you can zoom in much closer than with traditional microscopes, which are confined to the limits of visible light. In the electron microscope, electron waves pass with high energy right through the specimen. Magnetic fields produced by electromagnets influence the trajectories travelled by these electrons. The whole set-up is placed in a vacuum to prevent the influence of air molecules. Using an SPM (Scanning Probe Microscope) you can ‘feel’ the form of the nanoparticles using an extremely sharp needle. The Scanning Tunnelling Microscope (STM) and the Atomic Force Microscope (AFM) are members of the same family of microscopy instruments. Another useful device is the nano scale, which can weigh individual atoms. You do have to be careful to keep dust particles out of the lab; a dust particle is much bigger than a nanoparticle! This is why nano research is done in special clean rooms.

DIY with nano particles

The challenge for nano technologists is to find ways of using the tiniest particles in the biggest applications. The advances promised by nanotechnology appeal to the minds of many. Fundamental research could eventually lead to efficient and targeted treatment of tumours; super-fast computers the size of a sesame seed, implants in the nervous system making it possible to cure physical handicaps by generating impulses, a lab-on-a-chip for a do-it-yourself diagnosis of your health in your own home, nanoparticles that filter harmful substances from water, pills with nanosensors for tracing diseases, and solar panels with organic solar cells and higher energy production. In other words, the science concerned with these inconspicuous but consequential particles is going to change our lives drastically. This is an amazingly far-reaching science and encompasses the most divergent disciplines: physics, chemistry, biology, medical sciences and materials science, whereby close collaborations with product developers, designers, artists and architects are already producing useful results and bridging the gap between fundamental research and actual products.

Nano particles in our bodies?

Nanotechnology offers a new dimension of healthcare applications that could make life easier and even improve the quality of the natural environment, such as in the case of sustainable and energy-efficient products and increased food production. Too good to be true? Maybe we need to watch our step because of the dangers of nanotechnology? Nanotechnology, after all, also contains inherent risks. What will those manufactured nanoparticles get up to in our bodies? Do scientists actually know what the effects will be? We don’t even know all the effects of ‘non-nano’ chemicals, let alone nanoparticles. One thing we do know: once in, it is extremely difficult to remove these particles from the body again. So it is definitely worthwhile doing extensive studies on the toxicity of nanoparticles – in their various shapes and dosages – for the human body... before we all rigorously start slapping on sunscreen, only one of the many products containing nanoparticles that have been available in shops since 2006. And the integration of nano-, bio- and information technology is already underway... Whichever way you look at it, Nano is the future!

Links

Acknowledgements

Nano LinX was made possible thanks to the kind support of Nanopodium. Nanopodium is an initiative of the ‘independent Committee for the Societal Dialogue on Nanotechnology in the Netherlands’ (onafhankelijke Commissie Maatschappelijke Dialoog Nanotechnologie). This is a platform for exchanging thoughts, opinions, ideas and suggestions with the aim of stimulating a public dialogue on the opportunities and threats of nanotechnology for individuals and for society.

Nanopodium | Secretariat of the Committee for the Societal Dialogue on Nanotechnology

Herengracht 141, 1015 BH Amsterdam

tel.: 020 535 2244 | fax: 020 428 9656 | secretariaat@nanopodium.nl | www.nanopodium.nl

Author

I.C. Veldman, MA