Did you watch the movie ‘Spider Man’, that recently set the box office on fire? No, I am not about to begin yet another ‘super hero’ story. This is a story of the super technology that was used innovatively in this film, Yes, I am talking about Nanotechnology...
The members of the world of Nanotechnology are things smaller than 100 nanometers. Sounds common? Just wait … the length of one nanometer is spanned by 3-10 atoms! Still wondering how small can that be? Let me help. The diameter of a human hair is about 20,000 nm wide and a smoke particle is about 1,000 nm in diameter!!! This means that Nanotechnology deals with things that are more than 200 times smaller than your single hair strand! Exciting isn’t it?
Nanotechnology was first mentioned (in concepts) by physicist Richard Feynman at an American Physical Society meeting on December 29, 1959.
The term ‘nanotechnology’ was defined by Tokyo Science University Professor Norio Taniguchi in 1974 as “‘Nanotechnology’ mainly consists of the processing of, separation, consolidation, and deformation of materials by one atom or one molecule.” Dr. Eric Drexler explored the basic idea of this definition in depth in 1980s.
The term ‘nanotechnology’ is now used for ‘anything smaller than microtechnology,’ (that are nanoscale in size). But, in its original sense, ‘nanotechnology’ refers to the ability to make complete and high performance nanoscale products, and bigger products from nanoscale components.
There are two ways to engineer Nanomaterials: Top-down approach (a bulk material is reduced to nanoscale size) and Bottom-up approach (larger structures are built or grown atom by atom or molecule by molecule).
When materials are engineered and reduced to the nanoscale, they may suddenly show very different properties compared to what they show on a macroscale. For example, an opaque substance may become transparent (like copper); solids may turn into liquids at room temperature (gold); stable materials may turn combustible (aluminum); insulators may become conductors (silicon) or inert materials may become catalysts (platinum)!
Another fascinating fact is that as the nanoparticle gets smaller, its volume decreases, while its surface area increases proportionately. Its electronic structure changes, and it becomes a more efficient catalyst!
The number of dimensions of the nanoscale determines the type of nanostructure.
Nanotextured surfaces are one-dimensional on the nanoscale. The thickness of the surface of a nanotextured object is between 0.1 and 100 nm.
Nanotubes are two-dimensional on the nanoscale. The diameter of the tube is between 0.1 and 100nm and its length could be much greater.
Spherical nanoparticles are three-dimensional and between 0.1 and 100 nm in each spatial dimension.
Nanotechnology is used for a wide range of applications.
The size of nanomaterials is similar to that of most biological molecules and structures. So they are ideal for developing faster, flexible and more sensitive diagnostic devices, analytical tools, contrast agents (contrast agents for cell imaging), drug-delivery vehicles and developed tissue engineering (reproducing or repairing damaged tissue).
Chemical catalysis and filtration techniques are two prominent examples where nanotechnology already plays a role. Waste-water treatment, air purification and energy
storage devices can also be vastly improved by using nanoparticles.
Lights, fans, airconditioners, refrigerators--any electrical good that we use at home or office or in school--can be produced more cheaply by applying nanotech. These products are also far more energy efficient than the run-of-the mill alternatives. For example, efficient lighting like LEDs (Light-emitting diodes) or QCAs (Quantum Caged Atoms) reduce energy consumption Most importantly, nanotech batteries can be recycled!!
Nanotechnology products have many other useful characteristics. They range from being easy-to-clean to scratch-resistant. Modern textiles are wrinkle-resistant and stain-repellent. It is used very widely in the field of cosmetics as well. It can be applied in the production, processing, safety and packaging of food.
Its most useful application in household products is selfcleaning or “easy-to-clean” surfaces on ceramics or glasses. Nanoceramic particles have improved the smoothness and heat resistance of common household equipment like the flat iron.
Potential risks of nanotechnology health and environment are due to certain aspects that make nanoparticles risky, mainly their mobility and their increased reactivity.
Nanoparticles within the body are highly mobile and in some instances can even cross the blood-brain barrier. They can cause “overload” on phagocytes, cells that ingest and destroy foreign matter, thereby triggering stress reactions that lead to inflammation and weaken the body’s defense against other pathogens.
Not enough data exists to know for sure if nanoparticles can have undesirable effects on the environment. But studies of the health impact of airborne particles for assessing potential health risks from free nanoparticles have generally shown that the smaller the particles get, the more toxic they become.
Regulatory bodies in the US and in the European Union have concluded that nanoparticles form the potential for an entirely new risk and that it is necessary to carry out an extensive analysis of the risk. So far, these products and materials that contain them are not subject to regulations.
Apart from being a sizzling topic in many movies, Nanotechnology is also a part of our lives. But, fear about the limitless power of Nanotechnology and Advanced Nanotechnology has raised apprehensions about this immense field of science. Nevertheless, it continues to fascinate more and more people everyday.