# data[].attributes.body
OK to sum it all up. Applications of nantechnology are myriad and endless and we concentrated our picks to three from which we ended up on the topic we all considered much more important than the others POLLUTION CONTROL! I would like the article attached to be the backbone of our conversation

# data[].attributes.attachment_link.readable_text
During the last twenty years, scientists have been looking towards nanotechnology for the answer to problems in medicine, computer science, ecology and even sports. In particular, new and better techniques for pollution control are emerging as nanoparticles push the limits and capabilities of technology.

Nanoparticles, defined as particles 1-100 nanometers in length (one nanometer being the equivalent of one billionth of a meter) hold enormous potential for the future of science. Their small size opens up possibilities for targeting very specific points, such as diseased cells in a body without affecting healthy cells. In addition, elemental properties can change rather dramatically at the nanometer range: some become better at conducting heat or reflecting light, some change color, some get stronger, and some change or develop magnetic properties (1). Certain plastics at the nanometer range have the strength of steel. Tennis racquet manufactures already utilize nano-silicon dioxide crystals to improve equipment performance. The super-strength and other special properties emerge because microscale flaws between molecules are absent at the nanoscale (1). Nanoparticles without these flaws allow materials to reach the maximum strength of their chemical bonds.

These special properties and the large surface area of nano-particles prove valuable for engineering effective energy management and pollution control techniques. For example, if super-strength plastics could replace metal in cars, trucks, planes, and other heavy machinery, there would be enormous energy savings and consequent reduction in pollution. Batteries are also being improved using nanoscale materials that allow them to deliver more power faster. Nano-materials that absorb enough light for conversion into electrical energy have also been used to recharge batteries. Other environmentally-friendly technologies include energy efficient non-thermal white LED's, and SolarStucco, a self-cleaning coating that decomposes organic pollutants using photocatalysts.

Nanotechnology and Pollution Control
Pollution results from resource production and consumption, which in their current state are very wasteful. Most waste cannot be reintegrated into the environment effectively or cheaply. Thus, processes like petroleum and coal extraction, transportation, and consumption continue to result in photochemical smog, acid-mine drainage, oil slicks, acid rain, and fly ash. In his paper for the Foresight Institute, Stephen Gillett identifies the "Promethean Paradigm": the inefficient dependence on heat for energy since burning fuel discards much of its free energy during the conversion of chemical energy into heat and then to mechanical energy. Biological systems, on the other hand, efficiently oxidize fuel through molecular-scale mechanisms without extracting the chemical energy through thermalization (1). Overcoming the Promethean Paradigm requires controlling reactions at the nanoscale. Thus, nanofabrication holds much potential for effective pollution control, but it currently faces many problems that prevent it from mass commercialization - particularly its high cost.

The basic concept of pollution control on a molecular level is separating specific elements and molecules from a mixture of atoms and molecules (1). The current method for separating atoms is thermal partitioning, which uses heat to force phase changes. However, the preparation of reagents and the procedure itself are costly and inefficient. Current methods of energy extraction utilize combustion to create heat energy, most of which is wasted and results in unwanted byproducts that require purification and proper disposal. Theoretically, these high costs could be solved with the nanostructuring of highly specific catalysts that will be much more efficient (2). Unfortunately, we have yet to find an optimal way of obtaining the particles in workable form. Current means are essentially "shake and bake" methods called wet-chemical synthesis, which allows for very limited control on the final product and may still result in unwanted byproducts (1).

Although there are still many obstacles to overcome, the world is starting to recognize the potential in nanotechnology. In 2007, the Brian Mercer Award for Innovation from the Royal Society was awarded to researchers at the University of Bath for their work in developing nano-porous fibers that trap and remove carbon dioxide along with other pollutants and recycle them back into the production process. These fibers can recycle many forms of gases depending on their composition and the way they are spun (3). The high surface area characteristic of nano-sized particles makes such technology particularly efficient for applications with space constraints. Early tests have shown that this process will require only a small percentage of the energy used by current technology. Along with the award, the United Kingdom also granted £185,000 ($280,000) for the further development and commercialization of this technology. The hope is to eventually utilize it for pollution control by removing benzene from petrol vapor.

Air Pollution
Air pollution can be remediated using nanotechnology in several ways. One is through the use of nano-catalysts with increased surface area for gaseous reactions. Catalysts work by speeding up chemical reactions that transform harmful vapors from cars and industrial plants into harmless gases. Catalysts currently in use include a nanofiber catalyst made of manganese oxide that removes volatile organic compounds from industrial smokestacks (4). Other methods are still in development.

Another approach uses nanostructured membranes that have pores small enough to separate methane or carbon dioxide from exhaust (5). John Zhu of the University of Queensland is researching carbon nanotubes (CNT) for trapping greenhouse gas emissions caused by coal mining and power generation. CNT can trap gases up to a hundred times faster than other methods, allowing integration into large-scale industrial plants and power stations. This new technology both processes and separates large volumes of gas effectively, unlike conventional membranes that can only do one or the other effectively. For his work, Zhu received an $85,000 Foundation Research Excellence Award.

The substances filtered out still presented a problem for disposal, as removing waste from the air only to return it to the ground leaves no net benefits. In 2006, Japanese researchers found a way to collect the soot filtered out of diesel fuel emissions and recycle it into manufacturing material for CNT (6). The diesel soot is used to synthesize the single-walled CNT filter through laser vaporization so that essentially, the filtered waste becomes the filter.

Water Pollution
As with air pollution, harmful pollutants in water can be converted into harmless chemicals through chemical reactions. Trichloroethene, a dangerous pollutant commonly found in industrial wastewater, can be catalyzed and treated by nanoparticles. Studies have shown that these "materials should be highly suitable as hydrodehalogenation and reduction catalysts for the remediation of various organic and inorganic groundwater contaminants" (7).

Nanotechnology eases the water cleansing process because inserting nanoparticles into underground water sources is cheaper and more efficient than pumping water for treatment (8). The deionization method of using nano-sized fibers as electrodes is not only cheaper, but also more energy efficient (8). Traditional water filtering systems use semi-permeable membranes for electrodialysis or reverse osmosis. Decreasing the pore size of the membrane to the nanometer range would increase the selectivity of the molecules allowed to pass through. Membranes that can even filter out viruses are now available (9).

Also widely used in separation, purification, and decontamination processes are ion exchange resins, which are organic polymer substrate with nano-sized pores on the surface where ions are trapped and exchanged for other ions (10). Ion exchange resins are mostly used for water softening and water purification. In water, poisonous elements like heavy metals are replaced by sodium or potassium. However, ion exchange resins are easily damaged or contaminated by iron, organic matter, bacteria, and chlorine.

Cleaning Up Oil Spills
According to the U.S. Environmental Protection Agency (EPA), about 14,000 oil spills are reported each year (11). Dispersing agents, gelling agents and biological agents are most commonly used for cleaning up oil spills.

However, none of these methods can recover the oil lost. Recent developments of nano-wires made of potassium manganese oxide can clean up oil and other organic pollutants while making oil recovery possible (12). These nanowires form a mesh that absorbs up to twenty times its weight in hydrophobic liquids while rejecting water with its water repelling coating. Since the potassium manganese oxide is very stable even at high temperatures, the oil can be boiled off the nanowires and both the oil and the nanowires can then be reused (12).

In 2005, Hurricane Katrina damaged or destroyed more than thirty oil platforms and nine refineries (13). The Interface Science Corporation successfully launched a new oil remediation and recovery application, which used the water repelling nanowires to clean up the oil spilled by the damaged oil platforms and refineries (14).

Concerns
In 2009, NanoImpactNet, the European Network on Health and Environmental Nanomaterials will hold its first conference to study the impact of nanomaterials on health and environment. The small size of nanoparticles warrants investigation of the consequences of inhalation and absorption of these particles and their effects inside the body, as they are small enough to penetrate the skin and diffuse through cell membranes. The special properties of nanoparticles inside the body are unclear and unpredictable. Also, many are worried about the effects of nanoparticles on the environment. New branches of science such as eco-nanotoxicology have arisen to study the movement of nanomaterials through the biosphere. We do not yet know how much will be absorbed by the soil, air, or water, and how severely the widespread presence of nanoparticles in the environment will impact the ecosystem. To address these concerns, NanoImpactNet aims to set up regulations and legislation to ensure that nanoparticles, with so much potential for cleaning up pollution, will not become a new form of pollution themselves.

Conclusion
Nanotechnology's potential and promise have steadily been growing throughout the years. The world is quickly accepting and adapting to this new addition to the scientific toolbox. Although there are many obstacles to overcome in implementing this technology for common usage, science is constantly refining, developing, and making breakthroughs.

References
1. S. L. Gillett, Nanotechnology: Clean Energy and Resources for the Future (2002). Available at http://www.foresight.org/impact/whitepaper_illos_rev3.PDF (5 January 2009)
2. S.L. Gillett, Nanotechnology. 7, 177-182 (1996)
3. A. McLaughlin, Pollution control technology wins Royal Society award (20 February 2007). Available at http://www.bath.ac.uk/news/2007/2/20/merceraward.html (29 November 2008)
4. Air Pollution and Nanotechnology. Available at http://www.understandingnano.com/air.html (18 December 2008)
5. J. Zhu, Dr John Zhu, School of Engineering (19 September 2007). Available at http://www.uq.edu.au/research/index.html?page=68941&pid=68941 (15 December 2008)
6. T. Uchida et al., Japanese Journal of Applied Physics 45, 8027-8029 (2006).
7. M.O. Nutt, J.B. Hughes, M.S. Wong, Environmental Science & Technology 39, 1346-1353 (2005).
8. Water Pollution and Nanotechnology. Available at http://www.understandingnano.com/water.html (17 December 2008).
9. F. Tepper, L. Kaledin, Virus and Protein Separation Using Nano Alumina Fiber Media. Available at http://www.argonide.com/Paper%20PREP%2007-final.pdf (5 January 2009)
10. D. Alchin, Ion Exchange Resins. Available at http://www.nzic.org.nz/ChemProcesses/water/13D.pdf (18 December 2008)
11. U.S. Environmental Protection Agency, Response to Oil Spills (18 September 2008). Available at http://www.epa.gov/emergencies/content/learning/response.htm (31 December 2008)
12. J. Yuan et al., Nature Nanotechnology 3, 332-336 (2008).
13. United States Department of Commerce, Hurricane Katrina Service Assessment Report. (June 2006). Available at http://www.weather.gov/os/assessments/pdfs/Katrina.pdf (17 December 2008).
14. B. Lamba, Nanotechnology for recovery and reuse of spilled oil. (9 September 2005). Available at http://www.physorg.com/news6358.html (10 December 2008).

# data[].attributes.attachment_link.title
Turning to Nanotechnology for Pollution Control: Applications of Nanoparticles

# data[].attributes.attachment_link.description
During the last twenty years, scientists have been looking towards nanotechnology for the answer to problems in medicine, computer science, ecology and even sports. In particular, new and better techniques for pollution control are emerging as nanoparticles push the limits and capabilities of technology. Nanoparticles, defined as particles 1-100 nanometers in length (one nanometer being...

# data[].attributes.body
Nanoparticles can be used to convert the contaminating chemical through a chemical reaction to make it harmless. this is so amazing

# data[].attributes.body
Ok so water pollution it is!!

# data[].attributes.body
Hmm...both are very important topics, im confused :D ok i go with Shodhan cuz world hunger can be reduced by efficient supply of food and as far as pollution is concerned we are very desperate for finding a solution

# data[].attributes.body
I want to vote for food since it could help us fight world hunger! and im sure more people are dying of hunger than of pollution

# data[].attributes.body
Ok we have three competitiors! what do you people think? Which one is the most feasible and the much needed breakthrough? LETS VOTE!

I cast for pollution :) since its the most concerning issue of today

# data[].attributes.body
interesting.....now POLLUTION the greatest menace of today, and how nanotechnology can help us fight it. I put this question to the test and the results were astonishing!

# data[].attributes.attachment_link.description
Water Pollution Reduction Using Nanotechnology: Discussion of how nanotechnology can be applied to cleaning polluted water and a listing of companies working in this area

# data[].attributes.body
Good one i vote for this

# data[].attributes.body
WOAH!! amazing! ok now that we have one topic, my pick is use of nano-tech in foodstuffs> Look What I found

# data[].attributes.body
OMG! thats jaw-dropping

# data[].attributes.body
hey guys i found this really cool article on nanotechy cancer treatments, this cool innovative way how scientiscts used the dye in your blue jeans or your ballpoint pen has also been paired with gold nanoparticles to fight cancer.

# data[].attributes.attachment_link.readable_text
Nanotechnology is one of the most popular areas of scientific research, especially with regard to medical applications. We've already discussed some of the new detection methods that should bring about cheaper, faster and less invasive cancer diagnoses. But once the diagnosis occurs, there's still the prospect of surgery, chemotherapy or radiation treatment to destroy the cancer. Unfortunately, these treatments can carry serious side effects. Chemotherapy can cause a variety of ailments, including hair loss, digestive problems, nausea, lack of energy and mouth ulcers.

But nanotechnologists think they have an answer for treatment as well, and it comes in the form of targeted drug therapies. If scientists can load their cancer-detecting gold nanoparticles with anticancer drugs, they could attack the cancer exactly where it lives. Such a treatment means fewer side effects and less medication used. Nanoparticles also carry the potential for targeted and time-release drugs. A potent dose of drugs could be delivered to a specific area but engineered to release over a planned period to ensure maximum effectiveness and the patient's safety.

These treatments aim to take advantage of the power of nanotechnology and the voracious tendencies of cancer cells, which feast on everything in sight, including drug-laden nanoparticles. One experiment of this type used modified bacteria cells that were 20 percent the size of normal cells. These cells were equipped with antibodies that latched onto cancer cells before releasing the anticancer drugs they contained.

Another used nanoparticles as a companion to other treatments. These particles were sucked up by cancer cells and the cells were then heated with a magnetic field to weaken them. The weakened cancer cells were then much more susceptible to chemotherapy.

It may sound odd, but the dye in your blue jeans or your ballpoint pen has also been paired with gold nanoparticles to fight cancer. This dye, known as phthalocyanine, reacts with light. The nanoparticles take the dye directly to cancer cells while normal cells reject the dye. Once the particles are inside, scientists "activate" them with light to destroy the cancer. Similar therapies have existed to treat skin cancers with light-activated dye, but scientists are now working to use nanoparticles and dye to treat tumors deep in the body.

From manufacturing to medicine to many types of scientific research, nanoparticles are now rather common, but some scientists have voiced concerns about their negative health effects. Nanoparticles' small size allows them to infiltrate almost anywhere. That's great for cancer treatment but potentially harmful to healthy cells and DNA. There are also questions about how to dispose of nanoparticles used in manufacturing or other processes. Special disposal techniques are needed to prevent harmful particles from ending up in the water supply or in the general environment, where they'd be impossible to track.

Gold nanoparticles are a popular choice for medical research, diagnostic testing and cancer treatment, but there are numerous types of nanoparticles in use and in development. Bill Hammack, a professor of chemical engineering at the University of Illinois, warned that nanoparticles are "technologically sweet" [Source: Marketplace]. In other words, scientists are so wrapped up in what they can do, they're not asking if they should do it. The Food and Drug Administration has a task force on nanotechnology, but as of yet, the government has exerted little oversight or regulation.

For more information on nanoparticles, medical research and other related topics, please check out the links on the next page.

# data[].attributes.attachment_link.description
Nanotechnology is one of the most popular areas of scientific research, especially with regard to medical applications. We've already discussed some of the new detection methods that should bring about cheaper, faster and less invasive cancer diagnoses. But once the diagnosis occurs, there's still the prospect of surgery, chemotherapy or radiation treatment to destroy the cancer.

# data[].attributes.body
Hmm...ok now since venkys topic is happening and very important. (nanotechnology in medicines specialized in cancer) i think we should really look into it

# data[].attributes.body
Me too !!

# data[].attributes.body
:D haha yea that seems like a dream but i too agree it seems very unlikely

# data[].attributes.body
Ok although my article sounds very out of the world, its very unlikely we are going to experience growing cars atleast in our lifetime. So lets rule that out

# data[].attributes.body
WOW that was interesting so basically now we have to narrow down to few feasible applications. Since we have all had our share of researching in the nanotechnology. Lets pick out a few topics

# data[].attributes.body
Hey guys, i read this article on applications of nanotechnology on clothing fabrics pretty interesting! Check it out

# data[].attributes.attachment_link.readable_text
The Consumer Products Inventory lists over 1,600 products that have been identified by the manufacturer as containing nanoparticles - particles between one and 100 nanometres (between one and 100 billionths of a metre) across. Last month in this series on nanotech in household items, we looked at toothpaste. This month: clothing.

Several types of nanoparticles are added to the clothes we wear, including:

Microbe-killing silver

Silver nanoparticles are added to clothing for their powerful ability to kill bacteria and fungi, and to prevent the nasty odours they cause. Nanosilver particles release positively charged ions that stop bacterial cells functioning. The particles' tiny size means the garment stays soft and wearable.

Silica for waterproofing and stain resistance

Nanoparticles of silica incorporated into the weave of a fabric or sprayed onto its surface create a coating that repels water and stain-producing liquids. The angle and roughness of the silica coating creates enough surface tension to ensure that liquids form beads that roll off the fabric rather than soaking into it.

Sunblocking titanium dioxide and zinc oxide

Ever got sunburnt through your T-shirt? Nanoparticles of titanium dioxide or zinc oxide are incorporated into textiles to protect your garments - and your skin - from sun damage. Both particles scatter the ultraviolet light in sunlight, and do so more effectively as nanoparticles rather than as larger particles.

Antistatic particles

Some fabrics - particularly synthetics such as polyester and nylon - tend to gather static charge. Whisk a top over your head and your hair stands on end. But nanoparticles that conduct electricity, such as zinc oxide, titanium dioxide and antimony-doped tin oxide, can help disperse this charge.

At the moment, clothes featuring nanotechnology are largely made from standard fabrics upon which a nano-coating has been applied. But in the future we're likely to see more fabrics made from nanofibres, with nanoparticles and nanofilaments an integral part of the weave. A new era of "smart" fabrics, for example, could automatically respond to your body and the environment around you.

Safety

Natalie von Goetz from the Swiss university ETH Zürich has been studying whether the nanoparticles on fabric are dislodged during wear. "We tested whether nanoparticles are released into sweat under laboratory conditions, because if they are, they might be taken up by the skin," she explains. While clothes treated with titanium dioxide weren't found to release particles, nanosilver - the most widely used nanoparticle in the world - is shed from clothing in sweat.

Rickard Arvidsson from Chalmers University of Technology in Gothenburg, Sweden, thinks this could pose a problem. "While nanosilver - and silver in general - is not particularly toxic to humans, it could be very toxic to aquatic life," he explains. Arvidsson's research has shown that if nanosilver is extensively used in clothing, it could lead to high concentrations of silver in the sludge from waste water treatment plants.

Both he and von Goetz believe that research into their potential risks is lagging behind the commercialisation of nanomaterials.
Topics

# data[].attributes.attachment_link.title
The nanotechnology in your clothes | Holly Cave

# data[].attributes.attachment_link.description
The Consumer Products Inventory lists over 1,600 products that have been identified by the manufacturer as containing nanoparticles - particles between one and 100 nanometres (between one and 100 billionths of a metre) across. Last month in this series on nanotech in household items, we looked at toothpaste. This month: clothing.

# data[].attributes.body
Topping on for what Shodhan, i would like to continue the topic by introducing to you guys the various applications of NanoTechnology in the field of medicine and treatment.

# data[].attributes.attachment_link.readable_text
Nanotechnology, the manipulation of matter at the atomic and molecular scale to create materials with remarkably varied and new properties, is a rapidly expanding area of research with huge potential in many sectors, ranging from healthcare to construction and electronics. In medicine, it promises to revolutionize drug delivery, gene therapy, diagnostics, and many areas of research, development and clinical application.

This article does not attempt to cover the whole field, but offers, by means of some examples, a few insights into how nanotechnology has the potential to change medicine, both in the research lab and clinically, while touching on some of the challenges and concerns that it raises.

What is Nanotechnology?

The prefix "nano" stems from the ancient Greek for "dwarf". In science it means one billionth (10 to the minus 9) of something, thus a nanometer (nm) is is one billionth of a meter, or 0.000000001 meters. A nanometer is about three to five atoms wide, or some 40,000 times smaller than the thickness of human hair. A virus is typically 100 nm in size.

The ability to manipulate structures and properties at the nanoscale in medicine is like having a sub-microscopic lab bench on which you can handle cell components, viruses or pieces of DNA, using a range of tiny tools, robots and tubes.

Manipulating DNA

Therapies that involve the manipulation of individual genes, or the molecular pathways that influence their expression, are increasingly being investigated as an option for treating diseases. One highly sought goal in this field is the ability to tailor treatments according to the genetic make-up of individual patients.

This creates a need for tools that help scientists experiment and develop such treatments.

Imagine, for example, being able to stretch out a section of DNA like a strand of spaghetti, so you can examine or operate on it, or building nanorobots that can "walk" and carry out repairs inside cell components. Nanotechnology is bringing that scientific dream closer to reality.

For instance, scientists at the Australian National University have managed to attach coated latex beads to the ends of modified DNA, and then using an "optical trap" comprising a focused beam of light to hold the beads in place, they have stretched out the DNA strand in order to study the interactions of specific binding proteins.

Nanobots and Nanostars

Meanwhile chemists at New York University (NYU) have created a nanoscale robot from DNA fragments that walks on two legs just 10 nm long. In a 2004 paper published in the journal Nano Letters, they describe how their "nanowalker", with the help of psoralen molecules attached to the ends of its feet, takes its first baby steps: two forward and two back.

One of the researchers, Ned Seeman, said he envisages it will be possible to create a molecule-scale production line, where you move a molecule along till the right location is reached, and a nanobot does a bit chemisty on it, rather like "spot-welding" on a car assembly line. Seeman's lab at NYU is also looking to use DNA nanotechnology to make a biochip computer, and to find out how biological molecules crystallize, an area that is currently fraught with challenges.

The work that Seeman and colleagues are doing is a good example of "biomimetics", where with nanotechnology they can imitate some of the biological processes in nature, such as the behavior of DNA, to engineer new methods and perhaps even improve them.

DNA-based nanobots are also being created to target cancer cells. For instance, researchers at Harvard Medical School in the US reported recently in Science how they made an "origami nanorobot" out of DNA to transport a molecular payload. The barrel-shaped nanobot can carry molecules containing instructions that make cells behave in a particular way. In their study, the team successfully demonstrates how it delivered molecules that trigger cell suicide in leukemia and lymphoma cells.

Nanobots made from other materials are also in development. For instance, gold is the material scientists at Northwestern University use to make "nanostars", simple, specialized, star-shaped nanoparticles that can deliver drugs directly to the nuclei of cancer cells. In a recent paper in the journal ACS Nano, they describe how drug-loaded nanostars behave like tiny hitchhikers, that after being attracted to an over-expressed protein on the surface of human cervical and ovarian cancer cells, deposit their payload right into the nuclei of those cells.

The researchers found giving their nanobot the shape of a star helped to overcome one of the challenges of using nanoparticles to deliver drugs: how to release the drugs precisely. They say the shape helps to concentrate the light pulses used to release the drugs precisely at the points of the star.

Nanofactories that Make Drugs In Situ

Scientists are discovering that protein-based drugs are very useful because they can be programmed to deliver specific signals to cells. But the problem with conventional delivery of such drugs is that the body breaks most of them down before they reach their destination.

But what if it were possible to produce such drugs in situ, right at the target site? Well, in a recent issue of Nano Letters, researchers at Massachusetts Institute of Technology (MIT) in the US show how it may be possible to do just that. In their proof of principle study, they demonstrate the feasibility of self-assembling "nanofactories" that make protein compounds, on demand, at target sites. So far they have tested the idea in mice, by creating nanoparticles programmed to produce either green fluorescent protein (GFP) or luciferase exposed to UV light.

The MIT team came up with the idea while trying to find a way to attack metastatic tumors, those that grow from cancer cells that have migrated from the original site to other parts of the body. Over 90% of cancer deaths are due to metastatic cancer. They are now working on nanoparticles that can synthesize potential cancer drugs, and also on other ways to switch them on.

Nanofibers

Nanofibers are fibers with diameters of less than 1,000 nm. Medical applications include special materials for wound dressings and surgical textiles, materials used in implants, tissue engineering and artificial organ components.

Nanofibers made of carbon also hold promise for medical imaging and precise scientific measurement tools. But there are huge challenges to overcome, one of the main ones being how to make them consistently of the correct size. Historically, this has been costly and time-consuming.

But last year, researchers from North Carolina State University, revealed how they had developed a new method for making carbon nanofibers of specific sizes. Writing in ACS Applied Materials & Interfaces in March 2011, they describe how they managed to grow carbon nanofibers uniform in diameter, by using nickel nanoparticles coated with a shell made of ligands, small organic molecules with functional parts that bond directly to metals.

Nickel nanoparticles are particularly interesting because at high temperatures they help grow carbon nanofibers. The researchers also found there was another benefit in using these nanoparticles, they could define where the nanofibers grew and by correct placement of the nanoparticles they could grow the nanofibers in a desired specific pattern: an important feature for useful nanoscale materials.

Lead is another substance that is finding use as a nanofiber, so much so that neurosurgeon-to-be Matthew MacEwan, who is studying at Washington University School of Medicine in St. Louis, started his own nanomedicine company aimed at revolutionizing the surgical mesh that is used in operating theatres worldwide.

The lead product is a synthetic polymer comprising individual strands of nanofibers, and was developed to repair brain and spinal cord injuries, but MacEwan thinks it could also be used to mend hernias, fistulas and other injuries.

Currently, the surgical meshes used to repair the protective membrane that covers the brain and spinal cord are made of thick and stiff material, which is difficult to work with. The lead nanofiber mesh is thinner, more flexible and more likely to integrate with the body's own tissues, says MacEwan. Every thread of the nanofiber mesh is thousands of times smaller than the diameter of a single cell. The idea is to use the nanofiber material not only to make operations easier for surgeons to carry out, but also so there are fewer post-op complications for patients, because it breaks down naturally over time.

Researchers at the Polytechnic Institute of New York University (NYU-Poly) have recently demonstrated a new way to make nanofibers out of proteins. Writing recently in the journal Advanced Functional Materials, the researchers say they came across their finding almost by chance: they were studying certain cylinder-shaped proteins derived from cartilage, when they noticed that in high concentrations, some of the proteins spontaneously came together and self-assembled into nanofibers.

They carried out further experiments, such as adding metal-recognizing amino acids and different metals, and found they could control fiber formation, alter its shape, and how it bound to small molecules. For instance, adding nickel transformed the fibers into clumped mats, which could be used to trigger the release of an attached drug molecule.

The researchers hope this new method will greatly improve the delivery of drugs to treat cancer, heart disorders and Alzheimer's disease. They can also see applications in regeneration of human tissue, bone and cartilage, and even as a way to develop tinier and more powerful microprocessors for use in computers and consumer electronics.

What of the Future and Concerns Surrounding Nanomaterials?

Recent years have seen an explosion in the number of studies showing the variety of medical applications of nanotechnology and nanomaterials. In this article we have glimpsed just a small cross-section of this vast field. However, across the range, there exist considerable challenges, the greatest of which appear to be how to scale up production of materials and tools, and how to bring down costs and timescales.

But another challenge is how to quickly secure public confidence that this rapidly expanding technology is safe. And so far, it is not clear whether that is being done.

There are those who suggest concerns about nanotechnology may be over-exaggerated. They point to the fact that just because a material is nanosized, it does not mean it is dangerous, indeed nanoparticles have been around since the Earth was born, occurring naturally in volcanic ash and sea-spray, for example. As byproducts of human activity, they have been present since the Stone Age, in smoke and soot.

Of attempts to investigate the safety of nanomaterials, the National Cancer Institute in the US says there are so many nanoparticles naturally present in the environment that they are "often at order-of-magnitude higher levels than the engineered particles being evaluated". In many respects, they point out, "most engineered nanoparticles are far less toxic than household cleaning products, insecticides used on family pets, and over-the-counter dandruff remedies," and that for instance, in their use as carriers of chemotherapeutics in cancer treatment, they are much less toxic than the drugs they carry.

It is perhaps more in the food sector that we have seen some of the greatest expansion of nanomaterials on a commercial level. Although the number of foods that contain nanomaterials is still small, it appears set to change over the next few years as the technology develops. Nanomaterials are already used to lower levels of fat and sugar without altering taste, or to improve packaging to keep food fresher for longer, or to tell consumers if the food is spoiled. They are also being used to increase the bioavailablity of nutrients (for instance in food supplements).

But, there are also concerned parties, who highlight that while the pace of research quickens, and the market for nanomaterials expands, it appears not enough is being done to discover their toxicological consequences.

This was the view of a science and technology committee of the House of Lords of the British Parliament, who in a recent report on nanotechnology and food, raise several concerns about nanomaterials and human health, particularly the risk posed by ingested nanomaterials.

For instance, one area that concerns the committee is the size and exceptional mobility of nanoparticles: they are small enough, if ingested, to penetrate cell membranes of the lining of the gut, with the potential to access the brain and other parts of the body, and even inside the nuclei of cells.

Another is the solubility and persistence of nanomaterials. What happens, for instance, to insoluble nanoparticles? If they can't be broken down and digested or degraded, is there a danger they will accumulate and damage organs? Nanomaterials comprising inorganic metal oxides and metals are thought to be the ones most likely to pose a risk in this area.

Also, because of their high surface area to mass ratio, nanoparticles are highly reactive, and may for instance, trigger as yet unknown chemical reactions, or by bonding with toxins, allow them to enter cells that they would otherwise have no access to.

For instance, with their large surface area, reactivity and electrical charge, nanomaterials create the conditions for what is described as "particle aggregation" due to physical forces and "particle agglomoration" due to chemical forces, so that individual nanoparticles come together to form larger ones. This may lead not only to dramatically larger particles, for instance in the gut and inside cells, but could also result in disaggregation of clumps of nanoparticles, which could radically alter their physicochemical properties and chemical reactivity.

"Such reversible phenomena add to the difficulty in understanding the behaviour and toxicology of nanomaterials," says the committee, whose overall conclusion is that neither Government nor the Research Councils are giving enough priority to researching the safety of nanotechnology, especially "considering the timescale within which products containing nanomaterials may be developed".

They recommend much more research is needed to "ensure that regulatory agencies can effectively assess the safety of products before they are allowed onto the market".

It would appear, therefore, whether actual or perceived, the potential risk that nanotechnology poses to human health must be investigated, and be seen to be investigated. Most nanomaterials, as the NCI suggests, will likely prove to be harmless.

But when a technology advances rapidly, knowledge and communication about its safety needs to keep pace in order for it to benefit, especially if it is also to secure public confidence. We only have to look at what happened, and to some extent is still happening, with genetically modified food to see how that can go badly wrong.

Written by Catharine Paddock PhD

# data[].attributes.attachment_link.title
Nanotechnology In Medicine: Huge Potential, But What Are The Risks?

# data[].attributes.attachment_link.description
Nanotechnology, the manipulation of matter at the atomic and molecular scale to create materials with remarkably varied and new properties, is a rapidly expanding area of research with huge potential in many sectors, ranging from healthcare to construction and electronics. In medicine, it promises to revolutionize drug delivery, gene therapy, diagnostics, and many areas of research, development and clinical application.

# data[].attributes.body
Okay guys here is the forum for our discussion on applications of nanotechnology. We all have done our reader's profile on nanotech. I would like to begin by stating my application- Growing of cars through smart seeds! An initiative by Mercedes

# data[].attributes.attachment_link.title
Mercedes-Benz BIOME Concept - could cars be grown in a lab?

# data[].attributes.attachment_link.description
Mercedes-Benz has developed a car that would be grown in a lab rather built on a production line.