nanoparticles

• Nanoparticles:


  Really tiny particles with the size of 1nm - 100nm

  • These particles only contain a FEW HUNDRED atoms

  
• Nanoparticles are used as catalysts to speed up the rate of a chemical reaction:


  As they have more surface area for their given volume:

  • only the exposed surface area that’s important
  • so much less of a material made of narrow particles is needed than a material made of bigger particles.

  Nanoparticles have a very high surface area to volume ratio. 

  
• Nanoscience:


  The field of research that focuses on the properties & applications of nanoparticles.

  
• As things get smaller, volume decreases more rapidly than their surface area does & so their surface area to volume ratio actually gets bigger.

  
• Nanomedicine:


  Nanoparticles in medicine like:

  • using fullerenes to deliver drugs around the body
  • as they’re tiny that they could deliver drugs directly to the inside of our cells.

  
• Nanoparticles in tiny electrical circuits:


  Some of them can conduct electricity, so we could make tiny computer chips.

  
• Nanoparticles containing the element silver:


  Known to have antibacterial properties

  • So we can insert them into surgical masks, wound dressings like plasters or deodorant to kill bacteria, to reduce the risk of infections & on the skin to prevent body odour

  
• The POTENTIAL harmful effects of nanoparticles:

  • They may enter cells & cause damage to our DNA
  • They may cause harm to oceanic environments
  • they're expensive

  
• Nanoscience is a relatively new field:

  Many of the benefits & risks of nanoparticles are not yet known to us.

  • So some products may not be released into the world until enough research has been carried out to ensure they are safe.

  
• Nanometres (nm)

  There's 1 BILLION nanometres in a metre

  • convert nm into m by MULTIPLYING by 1x10-9  & convert m into nm by DIVIDING by 1x10-9
• the 3 types of particles that exist:

  • coarse particles (PM10)
  • fine particles (PM2.5)
  • nanoparticles
• COARSE PARTICLES / dust (PM10):

  • Have diametres between 2.5x10-6 (2500nm) & 1x10-5 (10,000nm)

  FINE PARTICLES (PM2.5)

  • Have diametres between 1x10-7(100nm) & 2.5x10-6 (2500nm)  
• COSMETICS & SUNSCREEN:

  Nanoparticles can be added improve the quality of moisturisers without making them oily

  • Their HIGH SURFACE AREA TO VOLUME RATIO means that they can provide BETTER COVERAGE of the skin
  • so a SMALLER MASS of nanoparticles is needed to be effective
• • has a higher surface area to volume ratio
  • less material needed for the same effect
  • more light gets through

  
• pro:

  • stops unpleasant smells
  • can stop infections & kill bacteria

  Con:

  • expensive
  • can be harmful is breathed in