A REVIEW OF HOW NANOTECHNOLOGY RELATES TO VARIOUS DISCIPLINES
Physical and Biophysical Chemistry
Physical chemistry is an essential part of understanding the interactions that go into achieving novel properties that are now being found at the nano-scale. Practical applications range from modelling to produce nanoparticles of a consistent size to the examination of interactions at the interfaces that provide improved biocompatibility for tissue engineering.
Nanoparticulate titanium dioxide is being used in a diverse range of products, from sunscreens that offer protection from cancer causing ultraviolet (UV) radiation to nano-coatings on windows where the titanium dioxide actually uses UV light to break down dirt in self-cleaning windows. There also are air purifiers on the market that use similar catalytic processes, such as Nano Breeze.
Other examples include the cerium oxide nanoparticles used in diesel fuel, which make it more efficient for engines, provide better mileage, and reduce emissions from exhaust pipes.
Precious metals offer another interesting area of nanotechnology in chemistry. Scientists have found, for example, that gold nanoparticles offer significantly improved catalytic properties. And nanoparticulate silver, which provides anti-microbial properties, is being used in a variety of products, such as wound dressings, baby milk cartons to prevent cross-contamination, food storage containers, and in the plastic parts of refrigerators to prevent mold formation. If through nanotechnology, bacteria identification and food quality monitoring using biosensors, intelligent, active, and smart food packaging systems; nanoencapsulation of bioactive food compounds are few examples of applications of nanotechnology for the food industry. Nanotechnology can be applied in the production, processing, safety and packaging of food. A nanocomposite coating process could improve food packaging by placing anti-microbial agents directly on the surface of the coated film. Nanocomposites could increase or decrease gas permeability of different fillers as is needed for different products. They can also improve the mechanical and heat-resistance properties and lower the oxygen transmission rate.
Chemistry and Human Health
Some of the most significant developments in nanotechnology will come in the field of healthcare. Work on new diagnostics indicates that increased sensitivity at the nano-scale will enable problems to be detected before they have affected the body, thereby reducing patient suffering and the length of hospital stays. Developments in nanotechnology also are benefiting tissue engineering, with new materials and surfaces that are more biocompatible. Nanotechnology also is providing benefits to the field of drug delivery.
Nanotechnology is being focused on some of the most significant healthcare problems, including cardiovascular diseases, cancer, musculoskeletal and inflammatory conditions, neurodegenerative and psychiatric diseases, diabetes, and infectious diseases. In the USA, significant funding is going to nanotechnology and cancer therapy, some of which is directed toward investigating better targeting of problematic cells.
Organic and Biomolecular Chemistry
Organic chemistry is having a large influence on the pace of nanotechnology development. For example, improved composites are not achievable if the nanoingredient is not dispersed well in the polymer, so selection of the right "compatibilizer" is essential. There also is a great deal of work going on related to functionalizing carbon nanotubes for sensors.
A roadmap for the application of dendrimers into new materials, another discovery produced by nanotechnology, has been produced by scientists in Europe and it describes their use in new inks, paints, and composites. Medical applications are at an early stage for these organics, but they offer great potential since dendrimers represent engineering at a biological-size scale. They show excellent potential as carriers for imaging contrast agents for enhanced organ, vascular, or tumor imaging, and for diagnostics.
Nanocomposites are already finding extensive applications where modified clays, carbon nanotubes, and particulates are providing barrier properties, lighter weight and stronger polymers, and functionalized surface applications. In order to save energy, most car manufacturers are using clay composites to replace heavy metal parts in cars. Even the fuel lines in new cars are going plastic through the incorporation of carbon nanotubes into the polymers to dissipate a charge. However, it is with carbon nanotubes that we will see real weight reductions because they may offer components that are 50 to 100 times stronger than steel, at one sixth the weight. The implication of this for the aviation industry is revolutionary.
It is interesting to note, too, that car tires have been using carbon black nanoparticles for about a century now. This is the largest use of nanoparticles worldwide, at 6 million tonne per annum. Clay-based nanocomposites also provide barrier properties and are being used in food packaging applications to give longer shelf life by eliminating oxygen and UV. Functional films are just thin nanocomposite layers which offer surfaces that are anticorrosive, antiglare, antimicrobial, antiscratch, and heat resistant.