Nanotech & Materials

Question 1

Quantum Dots

Answer 1

semiconductors nanocrystals made from inorganic metals

2-10 nm in diameter.

Exhibit energy band gap that determines required wavelength of radiation absorption and emission spectra.

• The energy band gap increases with a decrease in size of the quantum dot.

Requisite absorption and resultant emission wavelengths dependent on dot size.

Question 2

Medical Imaging

Answer 2

• Qdots are much more resistant to degradation than other optical imaging probes such as organic dyes, allowing them to track cell processes for longer periods of time.
• Quantum dots offer a wide broadband absorption spectrum while maintaining a distinct, static emission wavelength.
  *

Question 3

Photostability

Answer 3

Regardless of which target was stained with QD-streptavidin, the fluorescent signal was very stable against photobleaching comparing with organic dyes

Question 4

Internalization of nanoparticles

Answer 4

Higher aspect ratio particles taken up faster

Rod-like taken up faster

Question 5

Carbon Nanotubes

Answer 5

• Carbon nanotube - tubes of carbon –as thin as one atom layer thick
• Very high strength
• Unusual electrical and thermal properties