Saturday, June 11, 2011

What is Nanotechnology?

Despite unprecedented government funding and public interest in nanotechnology, few can exactly define the scope, range or potential applications of this know-how. of the most pressing issues facing nanoscientists and technologists today is that of communicating with the non-scientific community. Because of decades of speculation, a few myths have grown up around the field, making it difficult for the general public, or indeed the business and financial communities, to understand what is a essential shift in the way they look at our interactions with the natural world. This editorial attempts to address a quantity of these misconceptions, and report why scientists, businesses and governments are spending giant amounts of time and funds on nanoscale research and development.

1. Introduction

Take a random choice of scientists, engineers, investors and the general public and ask them what nanotechnology is and you will receive a range of replies as broad as nanotechnology itself. For plenty of scientists, it is nothing startlingly new; after all they have been working at the nanoscale for plenty of years, through electron microscopy, scanning probe microscopies or basically growing and analysing narrow films. For most other groups, however, nanotechnology means something far more ambitious, miniature submarines in the bloodstream, little cogs and gears made out of atoms, space elevators made of nanotubes, and the colonization of space. It is no wonder people often muddle up nanotechnology with science fiction.

one. What is nanotechnology?

two. What is the nanoscale?

Although a metre is defined by the International Standards Organization as `the length of the path travelled by light in vacuum in the coursework of a time interval of 1/299 792 458 of a second' and a nanometre is by definition 10- 9 of a metre, this does not help scientists to communicate the nanoscale to non-scientists. It is in human nature to relate sizes by reference to everyday objects, and the commonest definition of nanotechnology is in relation to the width of a human hair.

Regrettably, human hairs are highly variable, ranging from tens to hundreds of microns in diameter (10-6 of a metre), depending on the colour, type and the part of the body from which they are taken, so what is necessary is a standard to which they can relate the nanoscale. than asking someone to imagine a millionth or a billionth of something, which few sane people can accomplish with ease, relating nanotechnology to atoms often makes the nanometre simpler to imagine. While few non-scientists have a clear idea of how giant an atom is, defining a nanometre as the size of ten hydrogen, or three silicon atoms in a line is within the power of the human mind to grasp. The exact size of the atoms is less significant than communicating the fact that nanotechnology is dealing with the smallest parts of matter that they can manipulate.

two. Science fiction

While there is a often held belief that nanotechnology is a futuristic science with applications 25 years in the future and beyond, nanotechnology is anything but science fiction. In the last 15 years over a dozen Nobel prizes have been awarded in nanotechnology, from the development of the scanning probe microscope (SPM), to the discovery of fullerenes. According to CMP Científica, over 600 companies are currently active in nanotechnology, from little venture capital backed start-ups to a quantity of the world's largest corporations such as IBM and Samsung. Governments and corporations worldwide have ploughed over $4 billion in to nanotechnology in the last year alone.  every university in the world has a nanotechnology department, or will have at least applied for the funding for.

Even more significantly, there's companies applying nanotechnology to a variety of products they can already buy, such as automobile parts, clothing and ski wax. Nanotechnology is already all around us in case you know where to look.

three. The nanotechnology industry

The confusion arises in part because plenty of people in the business world have no idea where to look. Over the last decade, know-how has become synonymous with computers, program and communications, whether the net or mobile rings. Plenty of of the preliminary applications of nanotechnology are materials related, such as additives for plastics, nanocarbon particles for improved steels, coatings and improved catalysts for the petrochemical industry. All of these are know-how based industries, possibly not new ones, but industries with multi-billion dollar markets.

It is increasingly common to listen to people referring to `the nanotechnology industry', like the program or mobile phone industries, but will such a thing ever exist? Plenty of of the companies working with nanotechnology are basically applying our knowledge of the nanoscale to existing industries, whether it is improved drug delivery mechanisms for the pharmaceutical industry, or producing nanoclay particles for the plastics industry. In fact nanotechnology is an enabling know-how than an industry in its own right. No would ever report Microsoft or Oracle as being part of the electricity industry, although without electricity the program industry could not exist. , nanotechnology is a essential understanding of how nature works at the atomic scale. New industries will be generated because of this understanding, as the understanding of how electrons can be moved in a conductor by applying a feasible difference led to electric lighting, the phone, computing, the net and plenty of other industries, all of which would not have been feasible without it.

While it is feasible to buy a packet of nanotechnology, a gram of nanotubes for example, it would have zero inherent value. The actual value of the nanotubes would be in their application, whether within existing industry, or to enable the creation of a whole new.

Shrinking machines down to the size where they can be inserted in to the human body in order to detect and repair diseased cells is a well-liked idea of the benefits of nanotechnology, and that even comes close to reality. Plenty of companies are already in clinical trials for drug delivery mechanisms based on nanotechnology, but regrettably none of them involve miniature submarines. It turns out that there's a whole range of more efficient ways that nanotechnology can enable better drug delivery without resorting to the use of nanomachines.

6. Fantastic voyage

 the idea of navigating ones way around the body at will does not bear serious scrutiny. Imagine trying to go against the flow in an arteryâ��it would be like swimming upstream in a fast flowing river, while boulders the size of houses, red and white blood cells, rained down on you. Current medical applications of nanotechnology are far more likely to involve improved delivery methods, such as pulmonary or epidermal methods to keep away from having to pass through the stomach, encapsulation for both delivery and delayed release, and finally the integration of detection with delivery, in order for drugs to be delivered exactly where they are needed, thus minimizing side effects on healthy tissue and cells. As far as navigation goes, delivery will be by the exact same method that the human body makes use of, going with the flow and `dropping anchor' when the drug encounters its target.

7. Shrinking stuff

However, nanotechnology offers us a way out of this technological and financial cul-de-sac by building devices from the bottom up. Techniques such as self assembly, perhaps assisted by templates created by nano imprint lithography, a notable European success, combined with our understanding of the workings of polymers and molecules such as Rotoxane at the nanoscale open up a whole new host of possibilities. Whether it is avoiding Moore's second law by switching to plastic electronics, or using molecular electronics, our understanding of the behaviour of materials on the scale of little molecules allows a variety of alternative approaches, to produce smarter, cheaper devices. The new understandings will also let us design new architectures, with the final result that functionality will become a more valid measure of performance than transistor density or operations per second.

Another common misconception is that nanotechnology is primarily concerned with making things smaller. This has been exacerbated by images of little bulls, and miniature guitars that can be strummed with the tip of an AFM, that while newsworthy, merely demonstrate our new found control of matter at the sub-micron scale. While  the whole focus of micro-technologies has been on taking macro-scale devices such as transistors and mechanical systems and making them smaller, nanotechnology is more concerned with our ability to generate from the bottom up. In electronics, there is a growing realization that with the finish of the CMOS roadmap in sight at around ten nm, combined with the uncertainly principal's limit of Von Neuman electronics at one nm, that merely making things smaller won't help us. Replacing CMOS transistors on a for basis with some type of nano tool would have the effect of drastically increasing fabrication costs, while offering only a marginal improvement over current technologies.

8. Nanotechnology is new

It often comes as a surprise to learn that the Romans and Chinese were using nanoparticles thousands of years ago. Similarly, every time you light a match, fullerenes are produced. Degusssa have been producing carbon black, the substance that makes automobile tyres black and improves the wear resistance of the rubber, since the 1920s. Of coursework they were not aware that they were using nanotechnology, and as they had no control over particle size, or even any knowledge of the nanoscale they were not using nanotechnology as currently defined.

What is new about nanotechnology is our ability to not only see, and manipulate matter on the nanoscale, but our understanding of atomic scale interactions.

9. Building atom by atom

 of the defining moments in nanotechnology came in 1989 when Don Eigler used a SPM to spell out the letters IBM in xenon atoms. For the first time they could put atoms exactly where they wanted them, even if keeping them there at much above absolute zero proved to be an issue. While useful in aiding our understanding of the nanoworld, arranging atoms together after the other is unlikely to be of much use in industrial processes. Given that a Pentium two processor contains 42 million transistors, even simplifying the transistors to a cube of 100 atoms on each side would need 42 x 102 operations, and that is before they start to think about the other material and devices needed in a functioning processor.

Compare this with the difficulty of producing anything organic atom by atom, a sausage for example. Everyone is familiar with the macroscale ingredients of a sausage, some meat, possibly some fat, cartilage or other forms of tissue, even some bone, all encased in animal gut. Never mind, argue the proponents of assemblers, things are simpler at smaller scales.

Of coursework they already have the ability to build things atom by atom, and on a giant scale; it is called physical chemistry, and has been in industrial use for over a century producing everything from nitrates to salt. To do this, they do not need any kind of tabletop assembler as in Star Trek, usually a few barrels of obtainable precursor chemicals and possibly a catalyst are all that is necessary.

In terms of return on our investment, a farmyard containing a few pigs is a way more effective sausage machine than they could ever design, and has several other by-products such as hams and a highly effective waste disposal technique. This serves to illustrate how far they are away from being able to replicate nature.

Zooming down to the microscale they still have far more complexity than they would like to try to replicate, with cells, cytoplasm, mitochondria, chromosomes, ribosomes and plenty of other highly complex items of natural engineering. Moving closer to the nanoscale, they still must deal with nucleic acids, nucleotides, peptides and proteins, none of which they fully understand, or expect to even have the computing power to understand in the near future.

In terms of capturing the public imagination, unleashing hordes of self-replicating devices that escape from the lab and assault anything in their path is always going to be popular. Regrettably nature has already beaten us to it, by several hundred million years. Naturally occurring nanomachines, that can not only replicate and mutate as they do so in order to keep away from our best attempts at eradication, but can also escape their hosts and travel with alarming ease through the atmosphere. No wonder that viruses are the most successful living organisms on the planet, with most of their `machinery' being well in to the nano realm. However, there's finite limits to the spread of such `nanobots', usually determined by their ability, or lack thereof, of converting a sufficiently wide selection of material needed for future expansion. Indeed, the immune systems of plenty of species, while unable to neutralize viruses without side effects such as runny noses, are so effective in dealing with this type of threat because of the wide selection of different technologies obtainable to a immense complex organism when confronted with a single purpose nano-sized. For any threat from the nano world to become a danger, it would must include far more intelligence and flexibility than they could possibly design in to it.

ten. Assault of the killer nanobots

11. Conclusions

Our understanding of genomics and proteomics is primitive compared with that of nature, and is likely to stay that way for the foreseeable future. For someone determined to worry about nanoscale threats to humanity ought to think about mutations in viruses such as HIV that would permit transmission by mosquitoes, or deadlier versions of the influenza virus, which deserve far more concern than anything nanotechnology may produce.

Nanotechnology, like any other branch of science, is primarily concerned with understanding how nature works. They have discussed how our efforts to produce devices and manipulate matter are still at a primitive stage compared to nature. Nature has the ability to design highly energy efficient systems that operate exactly and without waste, fix only that which needs fixing, do only that which needs doing, and no more. They do not, although day our understanding of nanoscale phenomena may let us replicate at least part of what nature accomplishes with ease.

While plenty of branches of what now falls under the umbrella term nanotechnology are not new, it is the combination of existing technologies with our new found ability to observe and manipulate at the atomic scale that makes nanotechnology so compelling from scientific, business and political viewpoints.

For the scientist, advancing the sum total of human knowledge has long been the driving force behind discovery, from the gentleman scientists of the 17th and 18th centuries to our current academic infrastructure. Nanotechnology is at a early stage in our attempts to understand the world around us, and will provide inspiration and drive for plenty of generations of scientists.

For business, nanotechnology is no different from any other know-how: it will be judged on its ability to make funds. This may be in the lowering of production costs by, for example, the use of more efficient or more selective catalysts in the chemicals industry, by developing new products such as novel drug delivery mechanisms or stain resistant clothing, or the creation of entirely new markets, as the understanding of polymers did for the multi-billion euro plastics industry.

Possibly the greatest short term benefit of nanotechnology is in bringing together the disparate sciences, physical and biological, who due to the nature of schooling often have had no contact since high school. than nanosubmarines or killer nanobots, the greatest legacy of nanotechnology may well show to be the unification of scientific disciplines and the resultant ability of scientists, when faced with an issue, to call on the resources of the whole of science, not of discipline.

Politically, it can be argued that fear is the primary motivation. The US has opened up a commanding lead in terms of economic growth, despite recent setbacks, as a result if the growth and adoption of information know-how. Of equal significance is the lead in military know-how as demonstrated by the use of unmanned drones for both surveillance and assault in recent conflicts. Nanotechnology promises far more significant economic, military and cultural changes than those created by the net, and with know-how advancing so fast, and development and adoption cycles becoming shorter, playing catch-up won't be an option for governments who are not already taking action.

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