nanotechnology

Chemistry only

Nanotechnology

Nanochemistry is the study of structures between 1 and 100nm in size. A nanometre (1nm) is one billionth of a metre, 1x10-9m. Normally in a science lab you would be used to working with volumes of around 50 to 100 ml or masses of substances around 5-10 grams. Nanochemistry is different from "normal chemistry", these tiny nano objects have different properties from bulk materials we are normally used to using in everyday life. Nanoparticles are much much smaller than normal everyday particles. To give an idea just how small nanoparticles are consider that a human hair has a diameter of about 0.08mm or 80 000 nm, the table below gives some size comparisons.

Particle Diameter
atom 1 x 10-10 m
fine particles (also called PM2.5) 1x10-7 to 2.5x10-6m
course particles (also called PM10 or simply dust particles These particles have diameters in the range 2500-10 000nm

Nanoparticles have different properties from bulk materials due to their very high surface area to volume ratio. Consider the following example to further illustrate the point, this shows how to calculate the surface area of cubes and it then compares the surface area of large and small cubes with their volumes:

calculating surface area

Uses of nanotechnology

Research into the uses of nanoparticles is an area which is very active. It could include making lighter, stronger, stiffer, more durable, more conductive and stronger materials. Nanoparticles are already all around you in a variety of everyday objects from electronic devices to the very clothes you are wearing e.g.

Buckyballs can deliver drugs directly to cancer cells These are only a few of the uses and possible uses of nanoparticles. This is a field of chemistry which will only grow in the future as more research into the uses of these new materials is carried out.

Safety concerns

nanotechnology dangers Nanotechnology is a new and fast growing area of research and development. However many of the long term harmful side effects of nanoparticles are not fully known. Some scientists are worried about the possible side-effects of these tiny particles. This includes:

  1. Possible lung damage by breathing in these nanoparticles. Pollutants from cars and factories release small particles into the air which cause damage to the lungs. It is likely that nanoparticles will do the same. e.g. carbon nanotubes have a similar shape to asbestos fibres and they have been shown to cause extensive damage to the lungs in rats.
  2. Nanoparticles can pass into the body through skin, lungs and digestive system where they can cause damage to living cells e.g. some anti-aging creams contain fullerenes and these are potentially toxic if they penetrate the skin.
  3. The release of nanoparticles into the water, air or soil can cause environmental problems e.g. nanoparticles with anti-bacterial properties can enter the water system and kill bacteria in many ecosystems and even essential bacteria such as those in sewage treatment. Other nanoparticles can stick to air pollutants and be transported vast distances. These nanoparticles can have toxic effect on many living organisms.

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