The word “nanotechnology” is derived from the Greek word for dwarf (nanos) and is broadly defined as the engineering and application of functional systems at the molecular scale. One nanometer (1 nm) is 0.0000000001m (or 10-9m) or about 50,000 times smaller than the diameter of a single human hair. To put it into a wider perspective, if a nanoparticle was the size of a football then a watermelon would be as big as the earth. Or, alternatively for the more hirsute, a nanometer is the amount an average man's beard grows in the time it takes him to lift the razor to his face.
The pictures below show three objects with their length measured in nanometers - the dot of an i, a human hair and a positively stained T-lymphocyte cell.
Entering the invisible universe of the nanoparticle is a trip into the unknown in more than just visibility terms; nanoparticles exhibit very different characteristics to those of matter visible to the naked eye as material properties are highly size-dependent. For example if you were nano-sized and dived into a swimming pool you would find that the water would be more like treacle and its viscosity would soon bring you to a sticky end.
While the coining of the term may be relatively recent, nanotechnology itself has been around for several millennia – in ancient times the Romans used nanoparticles to create colourful ceramics and manufacturers have been using nanoparticles in the production of rubber tyres since the early 20th century. Now in the 21st century many uses for nanotechnology are already widespread in modern life. Nanoparticles can be found in many common household items including:
The Project on Emerging Nanotechnologies estimates that 3-4 new nanotech products hit the market every week thanks to the almost unlimited number of potential applications of nanotechnology. A search of the esp@cenet patent database reveals over 20,000 patents worldwide containing the word “nano” and as techniques for molecular manipulation improve this number is likely to increase rapidly.
To find out more about the potential applications of nanotechnology read our applications tutorial. Further reading on on nanofabrication and the future of nanoparticles is also available via the Tutorials page.