Nanotechnology is the manipulation or self-assembly of individual atoms, molecules, or molecular clusters into structures to create materials and devices with new or vastly different properties. This technology can work from the top down (which means reducing the size of the smallest structures to the nanoscale e.g. photonics applications in nanoelectronics) or the bottom up (which involves manipulating individual atoms and molecules into nanostructures and more closely resembles chemistry or biology).
The word “nano” means 10-9, or one billionth of something. It is generally used when referring to materials with the size of 0.1 to 100 nanometres, however it is also inherent that these materials should display different properties from bulk (or micrometric and larger) materials as a result of their size. These differences include physical strength, chemical reactivity, electrical conductance, magnetism, and optical effects.
Nanoparticle can be synthesized using a variety of methods, including physical, chemical and biological. Development of reliable and eco-friendly processes for synthesis of nanoparticles is an important step in the field of application of nanotechnology. One of the options to achieve this objective is to use ‘natural factories’ such as Bacteria, Fungi, Algae, and plants, as biomass provides both reducing agents and capping agents required for nanoparticle synthesis.