Chapter 9: Nanoparticles

9.1-Nanoparticles

Nanoparticles are really tiny

• They have a diameter between 1nm(1x10-9) and 100nm(1x10-7)
• They have a large surface area to volume ration
  • The surface area to volume ratio is an important factor as it can affect the way that a particles behaves
  • Surface area to volume ratio = surface area / volume
  • As particles decrease in size, the size of their surface area increases in relation to their volume, which causes the surface area to volume ratio to increase
  • Nanoparticles have a very high surface area to volume ratio, this means the surface area is very large compared to the volume
  • This can cause the properties of a material to be different depending on whether it’s a nanoparticle or in bulk
  • For example, you’ll often need less of a material that’s made up of nanoparticles to work as an effective catalyst compared to a material made up of normal sized particles(containing billions of atoms rather than a few hundred)

9.2-Uses of Nanoparticles

Nanoparticles can be used in lots of things

• Finding new ways to use nanoparticles is a really important area of scientific research
• Here are some of the uses that have already been developed
  • They have a huge surface area to volume ratio so they could help make new catalysts
  • Nanomedicine is the idea that tiny particles, such as fullerenes, are absorbed more easily by the boy than most particles
  • This means they could deliver drugs right into the cells where they’re needed
  • Some nanoparticles have antibacterial properties
  • They can be added to polymers fibres that are then used to make surgical masks and wound dressings and they can also be added to deodorants
  • Nanoparticles are also being used in cosmetics
  • For examples, they’re used to improve moisturisers without making them really dry

The effects of nanoparticles on health aren’t fully understood

• Although nanoparticles are useful, the way they affect the body isn’t fully understood, so it’s important that any new products are tested thoroughly to minimise the risks
• Some people are worried that products containing nanoparticles have been made available before the effects on human health have been investigated properly, and that we don’t know what the long-term impacts on health will be
• As the long-term impacts aren’t known, many people believe that products containing nanoscale particles should be clearly labelled, so that consumers can choose whether or not to use them

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