22. Nanoparticles: Uses & Risks

Size: Nanoparticles are extremely tiny particles with a diameter between 1 nanometer (nm) and 100 nm.
Scale: They are so small that they cannot be seen even with a light microscope.
Nanoscience: The field of science dedicated to researching these particles and creating new materials with useful properties.

Property: Nanoparticles have a very large surface area to volume ratio.
Why it happens: As particles get smaller, their volume decreases much faster than their surface area.
Significance: Many uses of nanoparticles depend on their surface area. For example, as catalysts, only the exposed surface is involved in the reaction. Using nanoparticles means you need much less material to achieve the same effect compared to larger particles.

Medicine (Nanomedicine): * Researchers are looking into using fullerenes (hollow carbon spheres) to deliver drugs directly into cells.
Electronics:
- Some nanoparticles can conduct electricity, allowing for the creation of incredibly tiny electrical circuits and computer chips.
Antibacterial Properties:
- Silver nanoparticles are used in surgical masks and wound dressings (like plasters) to kill bacteria and reduce infection risks.
Cosmetics (Sun Creams):
- Nanoparticles provide better coverage and protection against harmful UV rays compared to traditional sunscreens.

Unknown Long-term Effects: Because nanotechnology is relatively new, the effects on the human body aren't fully understood. There is a concern that they might be able to enter the body and damage cells.
Environmental Impact: It is unclear what happens to nanoparticles (like those from sun cream) once they are washed into the sea and whether they could harm the environment.
Regulation: Some people argue for stricter regulation and clearer labeling of products containing nanoparticles until more thorough testing is completed.