Simply defined, nanotechnology is the application of nanoscience or the study of unique properties of matter that occur at the nanoscale (lengths of roughly 1 to 100 nanometers or one billionth of a meter). The properties of matter depend on size. At the nanoscale, the physical, chemical and biological properties of matter/material may differ when compared to similar bulk material, in part, due to the large surface area per unit of volume.
Operating in the nanoscale increases the proportion of atoms on the surface compared with internal atoms. Atoms at the surface often behave differently from those located in the interior of a grain or particle since they have a higher energy state. Chemical reactions take place between atoms and molecules at surfaces. For example, catalysis can be enhanced when using nanostructured materials. Tiny variations in structure and composition of nanostructured materials can have a dramatic effect.
Other properties such as magnetism, hardness, and electrical and heat conductivity can change substantially as size is reduced. The differences in these properties stem from surprising collective effects and so-called quantum-size effects that arise from confining electrons in nanometer-sized structures. [National Nanotechnology Initiative – Supplement to the President’s FY 2004 Budget page 16]
A National Science Foundation official defines nanotechnology more precisely as dealing with materials and systems, which have these key properties:
- have at least one dimension of about one 1 to 100 nanometers
- designed through processes that exhibit fundamental control over the physical and chemical attributes of molecular-scale structures
- can be combined to form larger structures. [Stix, G. Little Big Science. Sci Am. 2001;285:32-37]
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NUCRYST Pharmaceuticals nanocrystalline platform technology meets this definition of nanotechnology. SILCRYST™ nanocrystals and silver Rx nanocrystals operate in the nanoscale of 1 to 100 nanometers. NUCRYST is able to adjust process conditions and the nanocrystalline silver combines to form larger structures such as SILCRYST™ medical coatings.