NANO Science and Technology
What does “nano” mean?
Nano is a prefix used in the metric system that means 10-9 or one billionth (1/1,000,000,000).
Nanometer = 10-9 or one billionth of a meter
Nanosecond = one billionth of a second.
When things are measured using nanometers, this is called using the nanoscale. Ordinary objects are HUGE when measured on the nanoscale.
When things are measured using nanometers,
|Atom = ~0.1 nanometers
Typical bacteria = ~200 nanometers long
Human hair = ~10,000 nanometers in diameter
Piece of paper = ~100,000 nanometers thick
Girl 1.2 m (4ft) tall = ~1200 million nanometers tall
Nanoscience is about studying things at the smallest possible scale (the science of VERY tiny things). Nanotechnology is putting nanoscience into action to help solve our problems
Working at the nanoscale is like ‘zooming in’ to the level of atoms and molecules. At the nano level, things can look, behave and react differently. Many materials have different physical properties even though they're still the same materials. For example copper becomes see-through and gold becomes very chemically reactive. Nanoparticles also have more surface area so they are can be excellent catalysts - substances that speed up chemical reactions. Often, these properties are ‘tunable’. This means that they can be adjusted by changing the shape, size or composition of the nanoparticle.
One reason for these differences is that on the nanoscale the factors that affect things change. Gravity plays a really important role in our world, but at the nano level other forces like electromagnetic forces (electrical fields and magnetic fields) and thermal vibrations (atoms and molecules jiggling around to store heat) can become much more important. It’s like changing the rules of science.
What is nanotchnology?
Nanotechnology is about being able to see, measure, manipulate and manufacture things at the nanoscale. It is a fast-moving area of science and technology that really took off in the 1980s when Dr K. Eric Drexler’s ground-breaking book Engines of Creation: The Coming Era of Nanotechnology was published. This was also the decade when sophisticated microscopes appeared that were capable of manipulating atoms and molecules on the nanoscale.
Why learn about nanotechnology?
Nanotechnology has enormous long-term economic, social, environmental and political implications. Countries and companies around the world are investing billions of dollars each year to explore the use of nanotechnology for things like medical treatments, efficient energy production and transmission, preventing and reducing pollution, improving water quality, making stronger and lighter materials and much more.
Manipulating the basic building blocks of all matter create enormous opportunities, challenges and risks. All of us need to have a basic understanding of what nanotechnology is about so that we can play a part in making informed decisions about how to move forward as a society.
Uses of nanotechnology
Nanoparticles are versatile and can be designed into structures of a specific size, shape, chemical composition and surface design to create whatever is needed to do a particular job. For these reasons, nanomaterials are increasingly used to enhance the strength, versatility, value or taste of products. A few of the many ways that nanotechnology is applied in day to day life are:
Electronics - Displays on cellphones, laptops, flatscreen TVs and many more devices are often organic light-emitting diodes (OLEDs), which are made from plastic films built on the nanoscale.
Sunscreens - Some use nanoparticles of titanium dioxide or zinc oxide to coat the skin and block the sun’s ultraviolet rays.
Fabrics - Coating fabrics with zinc oxide nanoparticles provides UV radiation protection. Other fabrics use nanoparticle ‘whiskers’ to repel water and other substances, making them stain-resistant.
Medicine – Nanoparticles of silver on bandages makes them antimicrobial (silver ions block microbes' cellular respiration i.e. the silver smothers harmful cells). Researchers are developing nanoparticles to deliver medicine directly to diseased cells in the body. In the past decade, nanotechnology has emerged as a new and powerful weapon for the detection and treatment of cancer.
Sports gear – Examples of products made with nanomaterials are golf clubs, golf balls and tennis rackets.
Vehicle manufacture - Nano-coatings can be found on items like scratch-resistant car bumpers, anti-slip steps on vans and buses and corrosion resistant paints.
Is nanotechnology safe?
Nanotechnology sounds like a world of great promise, but there are controversial issues too that must be considered and resolved. Some people have raised concerns that nanoscale organisms or machines could harm human life or the environment. One problem is that tiny particles can be extremely toxic to the human body. No one really knows what harmful effect new nanomaterials or substances could have.
Chemical pesticides were not considered harmful when they were first used in the early decades of the 20th century; it wasn't until the 1960s and 1970s that their potentially harmful effects were properly understood. The bottom line is that we do not know for sure if nanotechnology is safe. However, a lot of scientists are working hard to answer that question.
Source: Mardyani S. (2011), Nanoparticles for Cancer Detection and Therapy: Towards Diagnostic Applications of Quantum Dots and Rational Design of Drug Delivery Vehicles (Thesis for Graduate Department of Institute of Biomaterials and Biomedical Engineering University of Toronto)
To learn more, check out these websites:
http://www.explainthatstuff.com/nanotechnologyforkids.html (for children)
http://www.nanooze.org/main/Nanooze/English.html (for children)