Nanotechnology can be viewed as the science and engineering included in the design, synthesis, characterization, and application of materials and devices whose smallest functional organization is on the nanometer level or one billionth of a meter. At these scales, consideration of individual molecules and interacting groups of molecules becomes important. Applications to medicine imply materials and devices designed to interact with the body at molecular scales with a high degree of specificity.
Nanotechnology and nanoengineering appear to produce important scientific and technological advances in diverse fields including medicine and healthcare. Materials and devices engineered at the nanometer scale imply controlled manipulation of individual constituent molecules and atoms in how they are arranged to form the bulk macroscopic substrate. This, in turn, means that nanoengineered substrates can be designed to exhibit very specific and controlled bulk chemical and physical properties as a result of the control over their molecular synthesis and assembly. For applications to medicine and healthcare, these materials and devices can be designed to interact with cells and tissues at a molecular level with a high degree of functional specificity, thus allowing a degree of integration between technology and biological systems. Nanotechnology is not in itself a single emerging scientific discipline but rather a meeting of traditional sciences such as chemistry, physics, materials science, and biology to bring together the required collective expertise needed to develop these novel technologies.
What is a Nanomaterial?
Nanoscience will impact the design and fabrication of new materials with innovative properties and functions. Contributions to this field include improving the properties of plastics, ceramics, coatings, composites, fibres and many more. Nanoscience also introduces an entirely new concept in material design. As a matter of fact, nature is a great source of inspiration to materials engineers.
The question: What is a‘nanostructured material’? must be considered. Nanostructured materials are solids or semi-solids characterized by a nano-sized inner structure. They differ from crystalline, microstructured and amorphous solids because of the scale order. In contrast, microstructured materials show structural variation only on a micron scale, whereas amorphous materials exhibit short-range order only. In nanostructured materials, the spatial order is at the nanoscale, which lies between the microscopic and the atomic scale.
Nanostructured materials differ from conventional polycrystalline materials in the size of the structural units of which they are composed. They can exhibit properties that are drastically different from those of conventional materials. This means that in a nanostructured material there is a large proportion of surface atoms. Due to the large surface area, bulk properties become governed by surface properties. Examples of nanostructured materials are nanoporous, nanocrystalline, nanocomposite and hybrid materials.
Methods in Nanotechnology
Different methods for the synthesis of nanoengineered materials and devices can accommodate precursors from solid, liquid, or gas phases. In general, most synthetic methods can be classified into two main approaches: “top down