<h1>Nanotechnology Applications</h1>

Nanobiotechnology

Nanobiotechnology is the unification of biotechnology and nanotechnology, thus it's a hybrid discipline dealing with the making of atomic-scale machines by imitating or incorporating biological systems at the molecular level, or building tiny tools to study or change natural structure properties atom by atom. This goal can be attained via a combination of the classical micro-technology with a molecular biological approach.



Tiny medical hardware can interact with tissue in the human body at a molecular level to conduct more precise diagnosis and healing of malignancy. Many illnesses and injuries have their origins in nanoscale processes. Accordingly, practical usage of nanotechnology to the practice of medical care and biomedical investigation unlocks opportunities to treat illnesses, repair injuries, and enhance human functioning beyond what is possible with larger scale techniques.

(Artery cleaning by Tim Fonseca)

However, the challenges facing scientists and engineers working in the field of nanobiotechnology are enormous and extraordinarily complex in nature. Using nanotechnology in biomedical sciences will imply the creation of materials and devices designed to interact with the body at sub-cellular scales with a high degree of specificity and even dangers involved.

Nanomedicine

Nanomedicine is the medical application of nanotechnology seeking to deliver a valuable set of research tools and clinically helpful devices in the near future. It ranges from the medical applications of nanomaterials, to nanoelectronic biosensors, and even possible future applications of molecular nanotechnology. The health care industry is predicted to receive the first significant benefits of nanotechnology. The driving force behind this prediction is that biological structures are within the size scale that researchers are now able to manipulate and control.



Investigators are looking to nanotechnology to develop highly sensitive disease detectors, drug delivery systems that only target the disease and not the surrounding healthy tissue, and nanoscale building blocks that help repair skin, cartilage, and/or bone. Other researchers are investigating the use of nanotechnology to keep the body from rejecting artificial parts, and to stimulate the body to regrow bone and other types of tissue.

Researchers are investigating nanoparticles as drug carriers. These nanoscale drug carriers could be coated with nano-sensors, which could recognize diseased tissues and attach to them, releasing a drug exactly where needed. Nanoparticles could also be used to enter damaged cells and release enzymes that tell the cells to auto-destruct, or they could release enzymes to try to repair the cell and return it to normal functioning.



Current problems for nanomedicine involve understanding the issues related to toxicity and environmental impact of nanoscale materials. Further down the line, the speculative field of molecular nanotechnology believes that cell repair machines could revolutionize the entire medical field.

Nanotech environmental applications

 

Nanofiltration

In much of the developing world, clean drinking water is hard to come by, and nanotechnology provides one solution. Nanoporous membranes are suitable for a mechanical filtration with extremely small pores smaller than 10 nm  and may be composed of nanotubes. Nanofiltration is mainly used for the removal of ions or the separation of different fluids. Magnetic nanoparticles offer an effective and reliable method to remove heavy metal contaminants from waste water by making use of magnetic separation techniques. Using nanoscale particles increases the efficiency to absorb the contaminants and is comparatively inexpensive compared to traditional precipitation and filtration methods.



Providing nanofiltration methods to developing countries, to increase their supply of clean water, is a very inexpensive method compared to conventional treatment systems. However, there remain issues as to how these developing countries will be able to incorporate this new technology into their economy without creating a dependency on foreign assistance. Some water-treatment devices incorporating nanotechnology are already on the market, with more in development. Low-cost nanostructured separation membranes methods proved to be effective in producing potable water in recent studies.

 

Nanotech in energy production

Nanotech researchers are working on the development of a solar panel/fuel cell combination. The idea behind the technology is that when the solar panel is producing energy, the fuel cell is running in reverse to collect excess energy, convert it to hydrogen, and store it. When the sun goes down and the solar panel is no longer producing energy, the fuel cell will run forward and produce energy from the hydrogen it has stored.

Today, there are a number of different types of fuels cells under development but there are still some challenges with this technology and nanotechnology can be the solution to overcome all those difficulties.



Researchers around the world are using nanotechnology to make new fuel cell membranes that would substantially increase the energy output. Nanomaterials are being developed to take the place of the highly expensive platinum parts in current fuel cells, and nanotubes hold promise as hydrogen delivery systems.



Right now we need silicon wafers to make solar panels, and these silicon wafers, like computer chips, require a large amount of fossil fuels for production. However, researchers are using nanotechnology to develop solar panels capable of harnessing not only the visible light from the sun, but the infrared spectrum as well, thus doubling the energy output. What's more, these new solar cells could be sprayed on surfaces like paint, making them highly portable. They hope to someday build a solar power station in space capable of catching the solar energy that bypasses the Earth every day and providing about nine times the efficiency of solar cells on Earth.

Nanotechnology in construction

Silica (SiO2) is present in conventional concrete as part of the normal mix. However, one of the advancements made by the study of concrete at the nanoscale is that particle packing in concrete can be improved by using nanosilica which leads to a densifying of the micro and nanostructure resulting in improved mechanical properties.



The use of nanotechnology helps to improve the properties of steel. The addition of copper nanoparticles reduces the surface un-evenness of steel, which then limits the number of stress risers, and hence fatigue cracking. Advancements in this technology using nanoparticles would lead to increased safety, less need for regular inspection regime and more efficient materials free from fatigue issues for construction.

Carbon nanotubes are a new discovery, whereas wood is an ancient material which has been used since the dawn of civilization. However, perhaps not surprisingly given nature's evolutionary process, wood is also composed of nanotubes or "nanofibrils"; namely, lignocellulosic (woody tissue) elements which are twice as strong as steel. Harvesting these nanofibrils would lead to a new paradigm in sustainable construction as both the production and use would be part of a renewable cycle. Some developers have speculated that building functionality onto lignocellulosic surfaces at the nanoscale could open new opportunities for such things as self-sterilizing surfaces, internal self-repair, and electronic lignocellulosic devices.


Research is being carried out on the application of nanotechnology to glass. Titanium dioxide (TiO2) nanoparticles are used to coat glazing since it has sterilizing and anti-fouling properties. The particles catalyze powerful reactions which breakdown organic pollutants, volatile organic compounds and bacterial membranes.

Coatings are extensively use to paint the walls, doors, and windows. Nanotechnology is being applied to paints to obtain coatings having self-healing capabilities and corrosion protection under insulation. Since these coatings are hydrophobic and repel water from the metal pipe, they can also protect metal from salt water attack.

Nanoelectronics

The aim of nanoelectronics is to process, transmit and store information by taking advantage of properties of matter that are distinctly different from macroscopic properties. Nanoelectronics mainly refers to the use of nanotechnology on electronic components, especially transistors and, although the term "nano" is generally defined as utilizing technology less than 100 nm in size, nanoelectronics often refers to transistor devices that are so small that inter-atomic interactions and quantum mechanical properties need to be studied extensively.



Currently the most active field of research is the fabrication and characterization of individual components that could replace the macroscopic silicon components with nanoscale systems. Examples are molecular diodes, single atom switches or the increasingly better control and understanding of the transport of electrons in quantum dot structures.

 

Nanotechnology in Clothing

Nanotechnology can improve fabrics, making them harder wearing and more resistant to dirt, water, oils or other chemicals. Many of these developments are based on what happens in nature. For example, the lotus leaf is covered in nanoscale waxy "bumps" which causes water to bead and be shed easily. Fruits such as peaches are covered in tiny hairs which achieve the same effect. By incorporating such features in manufactured materials they too can be made water and stain repellent.


Textiles with a nanotechnological finish can be washed less frequently and at lower temperatures. Nanotechnology has been used to integrate tiny carbon particles membrane and guarantee full-surface protection from electrostatic charges for the wearer.



Nanotechnology is also leading to the incorporation of other features in clothing. This includes electronics for regulating temperature and monitoring health, lighter impact resistant materials and even shape-changing and colour-changing abilities.

Nanotechnology in food

Researchers are using silicate nanoparticles to provide a barrier to gasses (for example oxygen), or moisture in a plastic film used for packaging. This could reduce the possibly of food spoiling or drying out.


Zinc oxide nanoparticles can be incorporated into plastic packaging to block UV rays and provide anti bacterial protection, while improving the strength and stability of the plastic film.
Nanosensors are being developed that can detect bacteria and other contaminates, such as salmonella, at a packaging plant. This will allow for frequent testing at a much lower cost than sending samples to a lab for analysis. This point-of-packaging testing, if conducted properly, has the potential to dramatically reduce the chance of contaminated food reaching grocery store shelves.

Research is also being conducted to develop nanocapsules containing nutrients that would be released when nanosensors detect a vitamin deficiency in your body. Basically this research could result in a super vitamin storage system in your body that delivers the nutrients you need, when you need them.

"Interactive" foods are being developed that would allow you to choose the desired flavor and color. Nanocapsules that contain flavor or color enhancers are embedded in the food; inert until a hungry consumer triggers them.


Researchers are also working on pesticides encapsulated in nanoparticles that only release pesticide within an insect's stomach, thus minimizing the contamination of plants themselves.
Another development being pursued is a network of nanosensors and dispensers used throughout a farm field. The sensors recognize when a plant needs nutrients or water, before there is any sign that the plant is deficient. The dispensers then release fertilizer, nutrients, or water as needed, optimizing the growth of each plant in the field one by one.

References:

http://www.discovernano.northwestern.edu
www.wikipedia.org
http://www.nanoforum.org
http://www.understandingnano.com
http://www.nanotech-now.com