Nanotechnology - A rapidly evolving frontier

The technological advance in the development of microprocessors for computer and electronic use occurs at an exponential rate, following the so-called Moore’s Law, which states that circuit density doubles roughly every two years. Gordon Moore was the co-founder of Intel. Thus, a single microprocessor or silicon chip which assumes an area the size of a fingernail can now accommodate an enormous number of 2.9 billion transistors! Each of these tiny transistors is capable of switching “on and off” about 300 billion times a second, thus providing a binary code of “zeroes and ones,” the basic language of computers.

But the shrinking of the transistor is believed to be approaching the fundamental physical limits. Thus, electronic engineers and physicists are exploring new ways of further shrinking circuitry — down to the atomic and molecular structure. With the advances in nanotechnology, it is now possible to create nanocircuits with the use of silicon or carbon “nanowires.”

Nanoscience and nanotechnology dev’t

Nanoscience and nanotechnology — the study and engineering of matter at the atomic and molecular scale — are undergoing rapid development. Nanostructures are reduced to nanometer size. A nanometer is a billionth of a meter or one can visualize it in terms of slicing a single strand of hair into 50,000 distinct sub-strands, each one a nanometer thick. This thickness is smaller than that of a red blood cell.

The beginnings of nanotechnology trace back from 1989 when IBM scientists used a scanning tunneling electron microscope and the equivalent of tiny tweezers to move around xenon atoms until they spelled the company’s three-letter logo. The same lab did a similar feat by arranging individual iron atoms to spell “atom” in Japanese characters.

Since then, global R&D initiatives have developed around this emerging nanotechnology frontier using new techniques as scanning-probe microscopy. This technique has made possible the study of single-molecule nanostructures.

One remarkable discovery is that at nano size scale, materials assume different chemical and physical quantum properties than those of the same material in bulk. For example, carbon atoms can conduct electricity and are stronger than steel when woven into hollow microscopic threads. Nanoparticles are also used as additives to strengthen polymer products or building materials to fortify the walls of any given structure, and to create tough, durable and yet lightweight fabrics.

Many breakthroughs in nanotechnology have resulted in the development of a range of existing materials such as carbon nanowires and nanotubes, nanocrystals, nanostructured metals and inorganic substances of varied applications.

For industry, nanostructures can create high-performance materials for engineering structures and electronic products. These stress-resistant materials have aerospace applications. For medicine, nanomaterials can be used as new drug delivery agents to diseased tissues and organs, improve image-enhancing techniques and develop miniaturized diagnostic devices. Nanomaterials can likewise be used in the microfabrication of blood vessels and in human tissue engineering.

For the environment, engineered nanomaterials can extract heavy metals and organic pollutants from water and soils. There are also many applications of nanotechnology in agriculture, from crop and food processing to packaging and storage.

Nanomaterials are also used in manufacturing commercial products like paper and wood materials with enhanced printability, stain-resistant clothing, suntan lotions, dental materials that coat, protect, and repair damaged tooth enamel, super-sensitive water filters, etc. A number of commercial products used in everyday life that contain nanomaterials are already available in the Philippines.

In 2008, worldwide sales of such nano-derived commercial products reached around $90 billion and the market outlook down the road is certainly exciting. It is for this reason that advanced countries as well as developing economies like China, India and Brazil are putting in a lot of investments in nanotechnology. China, for instance, invests around $180 million annually whereas India has put together a five-year R&D agenda worth $220 million. It will be prudent for the Philippines to craft its own investment plans on nanotechnology and build up the necessary technical workforce and physical infrastructure. The Philippine Council for Advanced Science and Technology Research (PCASTRD) of the Department of Science and Technology (DOST) has initiated moves toward this end.

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The author is a National Scientist and Professor Emeritus at UP Los Baños. E-mail him at [email protected].