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Nanotechnology can be described as manipulation of particles ranging from 1-100 nm in size to create new materials, devices, structures and systems.

At the beginning of ’80s in the previous century, scanning tunneling microscope (STM) is invented. Imaging the surfaces at the atomic level in water, air and other liquid and gas environments with temperatures ranging from ~zero Kelvin to couple hundred degrees Celsius, enabled scientists not just to learn a lot about the materials they were investigating, but also to manipulate them to create new and improved ones.

How small “nano” actually is? DNA molecule has 2.5 nm in diameter. Human hair is 80,000- 100,000 nm wide. One piece of writing paper is 100,000 nm thick.

How nanotechnology works? Two main principles are applied: “bottom up” and “top down”. “Bottom up” technique relies on molecular recognition and chemical bonding. Material or device is built up by molecules that assemble themselves in growing aggregates. Typical example of molecular recognition in nature is key-lock principle seen in enzyme – substrate biochemical reaction. The way nucleotides in DNA chain are arranged is another example of molecular recognition and self-assembly. “Bottom up” approach can result in more or less complex structure at the end. Specific configuration (with qualities of interest) is created by choosing complementary and mutually attractive components that will be arranged in well defined manner. Self-organization, self-healing and self-replication are the most prominent features of this method finding biggest application in biomimetic materials development.

Top down principle is using reverse strategy. Bulk structures are converted into nano particles by continuous slicing and cutting. Top down method is operating on the surface of the material of interest. Micro-machined gears (used for miniature motors, pumps, electronic circuits) that are final result of the silicon processing are the best examples of this type of nanotechnology. Biggest problem with this method are crystallographic damage, impurities in the sample and structural defects that are all together making manufacturing process very hard.

What are the most popular applications of nanotechnology?

In medicine, it is widely applied in diagnostics, for contrast agent development, for analytic tools and drug delivery vehicles, tissue engineering….

Green nanotechnology is applied to preserve natural environment and enhance sustainable management. Filters and membranes made of nanomaterials are used for air and waste water purification. Nanofiltration is effective for impurities larger than 10nm and ultrafiltration for those ranging from 10-100nm. Magnetic separation (using magnetic nanoparticles) is another way to remove heavy metals from the waste water. Besides being helpful in cleaning the environment, nanotechnology can reduce amount of energy we are currently using. Nice examples are light-emitting diodes and quantum caged atoms that are wasting less energy that conventional light bulbs. Also, nanomaterials deployed by swarm robotics can be used for “clean-up” actions after nuclear accidents.

Novel types of displays with lower energy consumption and high field emission are manufactured using the carbon nanoparticles. Being small in size, electro conductive and energetically efficient, they easily won the battle against the displays with cathode ray tube.

Low weight and size of nanomaterials is highly appreciated in aircraft and spacecraft manufacture: significant fuel saving is accomplished by decreasing equipment weight. Telescopes made of nanomaterials can provide more accurate info about the outer space as well as nanorobots that could physically explore Moon or Mars instead of us.

Food industry is using nanotechnology in production, processing, packaging and for safety evaluation. Gas permeability, heat resistance, mechanical properties of the food could be improved using the nanocomposits. Biosensors are used for safety assessment and quality control. Bioactive food ingredients could be encapsulated using nanotechnology as well. All things used in food industry need to be strictly tested and approved by the FDA before mass production start.

Sun-block creams are one of the examples of nanotech in cosmetic industry. Titanium oxide is agent that provides necessary UV protection.

Some parts of the clothes that we are wearing and a lot of sporting gear is made of nanomaterials. Socks, shoes, baseball bats, tennis balls… - they all have decreased weight, increased duration and resistance + can offer microbial protection...

Applications are endless. It’s estimated that every 3-4 weeks new nanotech product comes to the market. We’ve seen a lot so far, but I'm sure that biggest things are yet to come.