Nano = Dwarf (from the greek word nanos). Nano as a prefix indicates a size scale of less than 100 nanometres (nm). One nanometre is the equivalent of one billionth of a metre (10-9 metres). To put it in perspective, comparisons are often made with the width of a human hair which is roughly 80 000 nm. The nanoscale is on the scale of the sizes of the atoms and molecules.
Nanoscience: is the study of atoms, molecules and objects whose size is on the nanometre scale (1 – 100 nanometres).
Nanotechnology: is the design, charactersation, production and application of structures, devices and systems by controlled manipulation of size and shape at the nanometre scale, to produce structures, devices and systems with at least one novel or superior characteristic that arises out of the nanometre scale.
Nanomaterials: refer to nanoscale materials or materials with structural features (particle size or grain size, for example) of at least one dimension in the range 1 – 100 nm.
Nanoparticles: are new nanoscale molecules with novel properties, which behave as a unit in terms of its properties. Nanoparticles are already incorporated in products such as paint, cosmetics, tennis rackets, clothing, glass and computers.
Nanocrystals: are aggregates of anywhere from a few hundred to tens of thousands of atoms that combine into a crystalline form of matter known as a “cluster”. Typically they have dimensions of around ten nanometres in diameter.
Nanocapsules: are any nanoparticles that consist of a shell and a space, in which desired substances may be placed. Nanocapsules are being developed for medical applications, as they may be an efficient vehicle for delivering drugs to targeted sites.
Nanofibres: are fibres that have diameters equal to or less than 100 nm. They have a wide range of applications from medical to industrial products and high-tech applications in aerospace, energy storage, fuel cells and information technology. They are produced by a process called “electrospinning”.
Nanowires: are extremely thin wires with a diameter of the order of a few nanometers. They can have multiple applications in electronics, but are also finding applications in medicine.
Nanomicelles: are tiny particles, often made from phospholipids, which can be broken down in the body. Micelles can contain drugs and be used in targeted drug delivery in medicine.
Nanoshells: are nanoparticles that consist of an inner core of one type of material and an outer layer of another material only a few nanometres thick. Nanoshells can be used in medicine, for example in imaging applications.
Nanotubes or Buckytubes (Cylindrical Fullerenes): are formed by a specific arrangement of carbon atoms in a long, narrow shape. Carbon nanotubes have the highest strength-to-weight ratio of any known material. They are used with other materials to build lightweight space-craft and other structures. They are also being used in medical research.
Bucky balls (Spherical Fullerenes): are hollow spherical arrangements of carbon atoms. They are finding applications in electronics, materials and medicine.
Nanomedicine: refers to the medical application of nanotechnology. This includes drug delivery, medical imaging, surgery, etc.
Nano-architecture: refers to the architectural applications of nanotechnology, for example the nanomaterials that can be used in building design. Nano-architecture is also used to describe the forms and structures of materials at the nanoscale.
Nanobiotechnology: refers to the application of nanotechnology to biotechnology – for example, using nanotechnology to monitor or control biological processes.
Nanocrystallline silicon: is a form of porous silicon. It is used in solar cells.
Nanosensors: are engineered nanostructures, often made with carbon nanotubes and nanowires, which detect information and signals in their environment. Nanosensors can be used in medicine, in agriculture, in environmental monitoring, in food quality assessment, etc.
Drug delivery system: refers to both the construct of the drug (its delivery vehicle) and its method of administration.
Bioavailability: is the rate and extent to which the active ingredient in a drug or medicine is absorbed from the dosage and becomes available at the site(s) of action.
Efficacy: the ability of a chemical to have an effect when it binds to a receptor, i.e. the ability of a drug to affect its target.
Toxicity: refers to the ability of the substance to induce harmful effects.
Nanotoxicology is the study of the toxicity of nanomaterials. Nanotoxicology is a branch of bionanoscience which deals with the study and application of toxicity of nanomaterials. Nanotoxicological studies are intended to determine whether and to what extent these properties may pose a threat to the environment and to human beings. For instance, diesel nanoparticles have been found to damage the cardiovascular system in a mouse model.
Nanofabrication: is the design and manufacture of devices on the nanoscale.
Solar photovoltaics: refers to the conversion of solar energy into voltage or electrical current through solar panels.
Quantum dots: are semiconductor crystals (conduct electricity due to electron flow) a few nanometres thick. Simply, they absorb light and transfer energy to electrons to generate electricity. They are being used to develop more efficient solar panels.