Why nanostructures are unique and interesting?
All materials consist of two types of properties: Intrinsic and Extrinsic. Intrinsic properties like chemical reactivity, conductivity do not depend upon sizes. For example, if one-meter Copper wire is cut into a few pieces; the intrinsic properties of shorter wires remain same as the original wire. If the dividing process is repeated again and again, this invariance cannot be kept indefinitely. Certainly, we know that the properties changes when the wire is divided into individual Copper atoms (even more at the level of electrons, protons and neutrons). Significant property changes often start when we get down to the nanoscale.
They are nanoscale shells with submicroscopic colloidal drug carrying system. The typical size of the nanocapsule ranges from 10 mm-1000 nm. The specific size of nanocapsule depends on its use. Nanocapsule structure consists of a core and a shell which is made of polymeric material. These polymers are biodegradable as use in biological system. Nanocapsules can be used for a number of applications like cancer treatment, self-healing process, drug delivery, absorption of alcohol from bloodstream etc.
Marine brown algae produce an anionic biopolymer known as Alginate. It has been widely studied for particle formation in the size range of 100 nm to 2 mm for drug delivery.
Magnetic nanoparticles coated with the protective shells are widely used in technological applications such as in the transport of anticancer drugs, and in magnetic recording materials and have great potential in in-vivo biomedical applications such as in the contrast enhancement of magnetic resonance imaging (MRI). The carbon coating of metals presents an effective protection method against environmental degradation and has excellent adhesive bonding with the surface of the metal particles. Such carbon shells are airtight and protect the entrapped materials from oxidation, and they are generally known as carbon nanocapsules. Such nanocapsules are proposed as a new approach of the magnetic carriers for the administration of drugs and vaccines.
Nanoshell is a type of spherical nanoparticle containing dielectric core, covered by a thin metallic shell (usually gold). These nanoshells involve a quasi-particle in which the electrons simultaneously oscillate with respect to all the ions.
Nanoshells have a core of silica and a metallic outer layer. Nanoshells are used in nanomedicine as a tool for radiation therapy because of their ability to target tumors and they can be injected easily.
Nanowire is a nanostructure, with the diameter of the order of a nanometer. It is also the ratio of the length to width being greater than 1000. Nanowires can also be defined as structures that have a thickness or diameter constrained to tens of nanometers or less and an unconstrained length. Many different types of nanowires exist, including metallic (Ni, Pt, Au), semiconducting (silicon) and insulating silicon dioxide (SiO2). These light absorbing nanowires embedded in a flexible polymer film can be used to develop low cost flexible solar panels. Nanowires are potential candidates for sensor and biomedical applications.
It is composed of germanium sulfide (GeS), a semiconductor material. The layers of the flower allow a large amount of surface area to be created in a small area. Each sheet, petal of the flower, is only 20-30 nm thick and 100 µm long. The layering of the sheets can form different floral patterns. GeS is known its ability to absorb solar energy and convert it into a useable form of energy. It is also relatively cheap, which makes a difference between present technology and upcoming technology. The flower-like shape is perfect for improving energy storage cells: the more layers you work with, the greater the surface area and capacity to hold onto the energy.
It’s a tube like structure at nanoscale. Physically it appears as a black powder but when you observe this powder under electron microscope it looks like a tube. We can classify them according to material use in their production like carbon nanotube, boron nitride nanotube, silicon nanotube, inorganic nanotube and DNA nanotube etc.
Nanotubes, which are grown in a laboratory, are strong and exhibit many thermal and electrical properties that are desirable to chip makers. Carbon nanotubes have the potential to be used as semiconductors, for example, potentially replacing silicon in a wide variety of computing devices.
Nanotubes parameters like number of concentric cylinders, cylinder radius and cylinder length are calculated by using nanoscale in electron microscope. Some nanotubes have a property called chirality, an expression of longitudinal twisting. Multiple nanotubes can be assembled into microscopic mechanical systems called nanomachines.
A nanoring is a small ring like crystal. The nanoring was discovered by researchers at Georgia Institute of Technology and it was made by using zinc oxide, a semiconducting material.
Nanobelt is also a very thin & flat nanostructure in belt form. Nanobelts are pure, structurally uniform, and single-crystalline and mostly free of dislocations. Field-effect transistors, ultrasensitive nano-sized gas sensors, and nanocantilevers have been fabricated based on individual nanobelts.