nanoparticles and their uses

What is the range of the diameter for course particles (dust)?

2500nm-10 000nm

What is the range of the diameter for fine particles?

100nm-2500nm

What is the range of the diameter for Nanoparticles?

1nm-100nm

How does the SA:V ratio affect nanoparticles?

As particles decrease in size, the size of their surface area increases in relation to their volume, causing the surface area to volume ratio to increase

This can cause the properties of a material to be different depending on whether its a nanoparticles or a bulk

E.g: You’ll need less of a material that’s made up of nanoparticles to work as an effective catalyst compared to a material made up of nor al sized particles

What can nanoparticles be used for?

• Catalysts: high Sa:V ratio

• Nano-medicine: absorbed easily into the body and can be used to deliver drugs

• Electrical circuits for computer chips: conduct electricity

• Added to polymer fibres → surgical masks, wound dressings, deodorants: antimicrobial properties of silver nanoparticles

• Cosmetics: used in moisturises to make them less oily

What are nano particles currently being used for?

• Sun creams: better at protecting skin from UV rays and provided better skin coverage

What are the risks and controversies of using nanoparticles?

• Affect of products on the human body hasn’t been tested long-term

• Unknown if it causes any damage to cells

• If washed away can be damaging to the environment