Nanobiotechnology

Nanobiotechnology versus Bionanotechnology

While often used interchangeably, nanobiotechnology is the creation of nanoscale materials and devices that advance biotechnology and biomedical applications. Bionanotechnology is the employment of biological entities to develop or inspire devices at the nanoscale. As of 2010, the bulk of existing technologies relied on the use of nanoparticles. It is thought that in the coming years, the complexity of the new devices will grow from nanoparticles, to nanostructures, to fully integrated nanodevices. These devices will eventually be at the molecular scale—a dimension even smaller than a nanometer.

Production and Characterization of Nanoparticles

There are two common methods for making nanoparticles: chemical and physical. To produce metallic nanoparticles by chemical routes, metal slats are generally dissolved at specific rates as a precipitation agent is included to force the formation of nanoparticles. The size of these particles is often controlled by the steering speed, temperature, and rate of metal salt and precipitation agent addition to the reaction. Often, sonicators and dispersing agents are used to minimize the agglomeration of particles. Physical production methods often requires the formation of particles by utilizing a high-energy source that break down the bulk structures of raw materials. The chemical methods have the advantage of controlling the size and composition of the formed particles.

The principal physical parameters for the characterization of nanomaterials are size distribution, shape, chemical composition, solubility, surface properties (charge, composition), and the presence of impurities. As the size of the nanoparticles decreases, the surface area increases dramatically until the amount of surface molecules are such that their surface properties dominate. The nanoparticles have increased surface reactivity compared to bulk material, since more molecules are located on the nanoparticles surface in an energetically unstable state.

Free nanoparticles tend to agglomerate, resulting in bigger particles, which may preserve some of the nanoparticles properties, such as high surface area and reactivity. The tendency of nanoparticles to agglomerate can be enhanced or hindered by the modification of the surface. The particle size, size distribution, and morphology are often measured by electron microscopy and nanosizers. The element composition of the produced nanoparticles is often measured by an inductive-plasma emission spectrometer. A zeta potential device usually assesses the surface charge of the nanoparticles.

The nominal cut off of 100 nanometers (nm) to distinguish between nanomaterials and non-nanomaterials was publicized by the U.S. Environmental Protection Agency (EPA) and other agencies. However, as many applications are employing nanomaterials with sizes above 100 nm, scientists agree that the cut off of 100 nm is arbitrary. Though there are many reported potentials, this entry will emphasize applications that are already incorporated in products or are about to be commercialized.

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