Dr Atta-ur-RahmanTuesday, July 09, 2013
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The emergence of new technologies is opening up fantastic opportunities for developing countries. One such field is that of nanotechnology. Nanotechnology emerged serendipitously when it was found that remarkable changes of properties in materials occur when their sizes are reduced typically between 1 nanometre (nm) and 100 nm.
A nanometre is about the same proportion to a metre as a marble is to the earth. Gold for instance becomes blue-green, red or purple in colour, depending on the particle size, if its size is reduced to the nano scale. Smalley and Kroto, both Nobel prize winners, found that heating graphite to high temperature with lasers resulted in a new form of carbon that resembled molecular foot balls. These strange and exciting molecules have found many applications as super lubricants, for development of slow-release drugs and for fabricating new materials.
Nanotechnology is finding a multitude of applications in medicine, agriculture, food, water purification, cosmetics, electronics, new materials and many other fields. The US has the largest share (28 percent) in the nanotechnology market, followed by Japan (24 percent), and Europe (25 percent, mainly Germany, France and the UK). In the field of nano-electronics alone, the market size is estimated to be above $4 trillion and is growing rapidly. When one considers the fields of agriculture, pharmaceuticals etc, the potential is simply fantastic.
Nanotechnology is finding innumerable applications in medicine. Nano-medicines exhibit improved absorption in the human body and can, therefore, be used in lower doses with improved efficacy and lower toxicity. In medical imaging they provide better images of, for instance, cancerous tissues. Nanoparticles that have been appropriately engineered can deliver heat, light, drugs and other materials to diseased tissues without damaging healthy ones.
Nano agriculture-related products are estimated to have a market of $20 billion, which is expanding rapidly. Nanotechnology is now also being used in the storage and protection of food products. For example silver nanoparticles have been incorporated in plastic storage bins that kill the bacteria on contact and increase shelf life. To reduce and optimise the consumption of pesticides in agriculture, nanocapsules with pesticides incorporated in them have been developed. The pesticides are released only in the stomach of the insects, so that plants and humans are protected from their harmful effects.
Amazing smart materials are being developed. You may be driving a car tomorrow built of such memory materials. If you have an accident and the car is damaged, don't worry – the material will restore itself to its original shape as it has a memory. Self-healing paints have already been developed. When cars that have been painted with such paint suffer a scratch, the scratch 'magically' vanishes immediately.
Another incredible development is that of bulletproof paper! Made of nanocellulose, it is stronger than steel and impervious to bullets. New materials are also being developed using nanomaterials for use in space craft and airplanes, and longer-lasting lightweight batteries. Another interesting development has been the invention of specialised textile materials that have mosquito repellent properties built into their structure. This makes the use of insect repellent lotions and sprays unnecessary, and the mosquito repellent properties remain unaffected even after the clothing made from such materials is washed several times.
About 200 million persons suffer from malaria each year and about 700,000 die annually because of it. Such clothing may reduce the risk of malaria considerably. Nanotechnology has also been employed for the economical production of stronger lightweight textiles, tennis racquets and other sports goods. Indeed textiles using nanotechnology are estimated to have a market size of $115 billion.
The new smart materials can adopt different shapes ('morph') in response to electric currents or magnetic fields. The US army is using them in the form of powerful bulletproof 'living' exo-skeletons that can be worn by Robo-Cop type soldiers during combat. These suits can be connected to the thought waves of the soldier, so that they can react instantly. Smart Memory Alloys have also been 'noise cloaked', for use in silent stealth helicopters and ground vehicles. Objects fabricated with new 'metamaterials' can even be invisible.
A sinister development that has resulted from miniaturisation techniques and new materials has been the invention of insect-sized drones fitted with cameras and sound systems. They can be manipulated remotely and placed anywhere. The stealth materials used in the production of these drones prevent their detection by normal detection technologies that are available in most countries. Since they look like flies or other small insects they are completely camouflaged and undetectable to standard detection tools.
Fantastic developments are also taking place in the field of microelectronics. The use of a new carbon material, 'graphene' is having a profound impact on new electronic devices such as mobile phone batteries. Graphene has a honeycomb-like structure which is a single atom thick and lithium ion batteries made out of planar sheets of graphene now last 10 times longer than conventional batteries. The technology may also find applications in electric cars where the number of miles a car can be driven after a single charge is of critical importance.
Another interesting application of nanotechnology is the development of an 'electronic nose' that can detect tiny amounts of drugs, or explosives with a very high degree of sensitivity. This has been done by inserting certain receptor proteins on to carbon nanotubes. When the receptors interact with a target molecule an alarm is set off, alerting the user of the presence of a particular chemical in the immediate environment to the detection device.
Carbon nanotubes are about 10,000 times thinner than a human hair. They are now being used in many different applications including the rapid and sensitive detection of certain marker chemicals well before the onset of diseases, thereby allowing persons to take pre-emptive action. It has been found that one can develop solar cells using nanotubes, and these can then be painted on walls or windows, providing a source of clean energy.
Pakistan must not miss the boat in this field, as it did in the IT area. When I was the federal minister of science and technology, I established the National Commission of Nanotechnology in 2001. Unfortunately the government that followed decided that we had no need of this "useless field" as they called it and the commission stopped functioning.
Thousands of scholars were sent abroad for PhD degrees by the HEC in various fields including nanotechnology, and they are returning in large numbers. It is critically important for us to utilise their talents in academia and industry so that they can contribute to the process of development in such knowledge-intensive fields and to the rapid growth of exports from Pakistan.
The writer is the former chairman of the Higher Education Commission and currently president of Pakistan Academy of Sciences. Email: ibne_sina@hotmail.com
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