Threshold Concepts for Nanotechnology - Essay Example

Na chnology or macrotechnology is the application of engineering sciences that operate at the basic molecular or atomic level. This branch of science with its many threshold concepts is still at a very early stage of development and further extensive research work is on, so as to make this technology more advanced and be available in all walks of life. The implications of this technology are huge and with further advancement would bring about a revolutionary change in the field of medical sciences, information technologies, communication technologies and many other avenues of application sciences that touch our everyday lives. This technology, in the near future, if correctly tapped and well applied, would have a beneficial impact on human lives that would far outweigh its supposed negative effects. Introduction: Nanotechnology, the term refers to engineering systems that operate at the basic level of molecular or atomic scales. The term nano has been derived from the Greek word nanos, meaning a dwarf. It generally deals with structures that are measurable in a nanoscale (nanometers, that is, one billionth of a meter). The term nanotechnology was first coined in 1974 by Norio Taniguchi, a Japanese professor associated with the Tokyo Science University. Later in the eighties Eric Drexler did a lot of research work in this field and made this technology popular through his various books like ‘Engines of Creation’ and ‘Nanosystems’. In fact the book “Engines of Creation” is considered a pioneer of sorts in this field of nanotechnology. Richard Feynman in 1959 envisioned a world where this system of structuring from the bottom, starting at precision from the atomic level was theoretically possible. As Feynman (December, 1959) said in his lecture at the American Physical Society meeting “I want to build a billion tiny factories, models of each other, which are manufacturing simultaneously. . .The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom. It is not an attempt to violate any laws; it is something, in principle, that can be done; but in practice, it has not been done because we are too big”.(Feynman, 2008, cited in CRN-The Meaning of Nanotechnology). Body: Size definition of nanotechnology – This science refers to working with particles that are 100 nanometers in dimensions. One nanometer is about 1/80000 of a human hair diameter or 7 oxygen atoms or 3-4 water molecules in a line gives one nanometer. This comparison gives us an insight into the minuscule proportions and dimensions of one nanometer. However there are speculations and opinions are divided over fixing this cut off figure. Recently The EU’s Council of Ministers proposed the following definition for basic nanomaterial size as: “Any intentionally produced material that has one or more dimensions of the order of 100nm or less or is composed of discrete functional parts, either internally or at the surface, many of which have one or more dimensions of the order of 100nm or less, including structures, agglomerates or aggregates, which may have a size above the order of 100 nm but retain properties that are characteristic to the nanoscale.” (Nanoscience and Technology, 2004) The Institute of Nanotechnology in the U.K. also gives us the size definition as "science and technology where dimensions and tolerances in the range of 0.1 nanometer (nm) to 100 nm play a critical role." (Nanotechnology Industries, 2007). Pervasive definition of nanotechnology – The scope for modern or thresholds concepts of nanotechnology are broad and pervasive, that is, they will be touching all parts of our lives. Richard Feynman in his famous lecture “there is plenty of room at the bottom” outlined the benefits of manufacturing things by starting right from the lowest level and foresaw many of technologies that are in use today, like gene sequencing machines that can read DNA makeup, use of integrated circuits in computers and the use of electron microscope to store vast information in very small spaces. These revolutionary and threshold ideas are bringing about huge changes in the world of medicines and healthcare. These changes that have come with nanotechnology have led to a shift in man’s perception, which is both irreversible and not likely to ever forgotten. Some instances as to how nanotechnology has become all pervasive and has changed our lives are given below: a). Semi conductor devices – In 1968 Alfred Cho and John Arthur working at Bell Labs invented the Molecular beam epitaxy. It created a revolution in the field of compound semiconductor device fabrication allowing the one dimensional structuring of atomic layers one on top of the other. It was used in the information and technology sector and microprocessors were invented. A single silicon microchip that is only a few millimeters in dimension and comes very cheap nowadays, have more than 100 million transistors arranged in a file. These silicon chips have non magnetic sensor materials one nanometer thick, that are packed between magnetic layers and they have amazing storage capacity. Similar technology is used in CD payers where semi conductor laser is in use. Based on this concept extremely small micromechanical machines or microelectromechanical machines (MEMS) are used widely in the car and medical industry where both size and cost matter a lot. The scanning probe microscope invented in 1981 by Heinrich Rohrer and Gerd Binnig has a very sharp point that can scan images of atoms on the surfaces of various objects. This concept has also been used to move single molecules, by Jim Gimzewski and this moving around of individual atoms and molecules is known extreme nanotechnology. b). New carbon structures known as fullerene (carbon 60), later named as buckministerfullerene were discovered by Robert Curl Jr., Richard Smalley and Harold Kroto using nanotechnology. These spherical carbon structures, 0.7 nanometers in diameter, are a pure form of carbon like diamond and graphite. Carbon nanotubes, carbon like structures that extended from spherical to tubular forms, were also discovered in Japan in 1991 by Sumio Iijima. These nanotubes have certain very remarkable properties of either being metallic or semi conductors depending on the arrangement of carbon atoms within them. The metallic nanotubes which have mechanical properties that surpass those of steel and conductivity that is far better than copper is being used extensively to make electromagnetic shielding in combination with polymers to reduce static electricity in cars and also in mobile phones. They are also being touted as the future replacements of steel fibers. c). The latest threshold concept that the scientists are presently toying with, is the merging of nanotechnology with biotechnology and using it for the advancement and betterment of medical science and health care related research work. Electron beam lithography which was earlier used for electronic purposes is now being used in biology labs where it is being used to alter surfaces to facilitate the controlled growth of various biological species. The industries to be affected most by the development of this nanotechnology are the medical, material sciences and the information technologies. In the world of biomedicine and related health care the advancement of nanofabrication would affect the therapy and delivery of various drugs. Many drugs that are not water soluble, and very difficult to transport could be easily delivered in its nanosized particle form to any part of the world. Besides, scientists are looking to create a new approach in administration of drugs by using nano sized carriers that would release the drug at the right part of the body and over a long period of time. Extensive studies are going on in nanomedicine in the area of bioassays to develop better tools for disease diagnosis. Assistive techniques or devices are another field where nanotechnology can be used in the future, as for example, researchers are planning to create retinal implants using nanotechnology, for the blind. Information technology has used the application of nanosciences for their betterment by the invention of semiconductor devices, molecular electronics, spintronics, single electron transistors and nanotubes. Amazing storage capacities in small nanoscale sized chips have been made possible today, that are used extensively in computers and compact discs. Communications technology is also benefiting hugely from the invention of optical devices like the vertical-cavity surface-emitting-lasers or VCSELs and quantum dot lasers. Nanomaterials can also be used in the industries as filters to sieve out pollutants like heavy metals from the water. They can also be potentially used as a mechanism where electricity can be directly obtained from the chemical energy of fuel. Another potential application of nanotechnology is in the field of purification and desalination of water. Thus from the above example we can see that nanotechnology in the near future will be all pervasive, touching all aspects of our lives. Processes: There are two ways applied in nanotechnological constructions. These are the top down and the bottom up approach. The top down approach which makes a miniature of present day technologies is seen in the electronic industry, to create miniature integrated circuits where optical lithography is used to make transistor circuits of a few nanometer dimensions. Bottoms up or the process of self assembly where force is applied at the basic nanoscale level to create bigger structures. Scientists hope to make use of this approach and from the basic small atoms create larger macromolecular structures. As in any threshold technology nano or microtechnology has its own share of negative implications too. Ultra small carbon particles generally pose to be a health hazard for humans and other animals and may adversely affect the respiratory system and the heart. Research is also on as to whether certain nanomaterials are carcinogenic or not and if used in drug therapy whether these particles could cross the barrier to induce effects that are still unknown within the human body. Nano materials like titanium oxide (in sunscreen lotions), nanotubes and quantum dots are also under the health scanner at present. Researches where high levels of nano materials when introduced inside the bodies of animals have caused death very rapidly, has created controversy as to the usage limits of nano materials. Conclusion: Thus from what we see the potential uses of nanotechnology for the benefit of society as a whole and also its negative impact on humans, are all mostly under unexplored waters. They need to be tested more and further research work has to be done in this area to be able to come to a conclusion. The threshold concepts of nanotechnology are still at the threshold level with huge future potentials. Of course, certain amount of advancement has been made in the field of nanotechnology and from what little progress has been made; its effect on human lives has been huge. So one can safely conclude that the advancement in the threshold concepts of nanotechnology is for the betterment of human lives in most cases and the creation of further applications in this field will definitely be a boon for the society at large. References Feynman, R. (2008). CRN - The Meaning of Nanotechnology. http://www.crnano.org/whatis.htm . Date accessed 7/11/09. Nanoscience and technology. (2004).What is Nanotechnology. University of California. http://www.lanl.gov/mst/nano/definition.html Date accessed 11/11/09. Nanotechnology Industries. (2007). Solutions for the future- whatisit.com definition. http://www.nanoindustries.com/define.html Date accessed 11/11/09. Read More