Nanoscience and Nanotechnology
When atoms are arranged into very small particles they behave differently to ordinary materials made of the same atoms. A nanometre is one billionth of a metre and nanoparticles are a few nanometres in size.
Nanoparticles have very large surface areas, exposing many more atoms at their surface than normal materials. Electrons can move through them more easily than ordinaly materials. They can be very sensitive to light, heat, pH, electricity and magnetism.
Nanotechnology uses nanoparticles as very selective sensors, highly efficient catalysts, new coatings and construction materials with special properties, and to make drugs more effective.