Luminescence presentation
-
Upload
guestdebbbc -
Category
Documents
-
view
2.821 -
download
3
description
Transcript of Luminescence presentation
From The Deep Sea to the Crime Lab
Luminescence
Light
•Electrons are energized and photons are released to make light
•The electrons in higher orbitals emit a photon when they fall back to their original orbital
•Our eyes pick up the photons being emitted by the light source
•Chemoluminescence - light produced by a chemical reaction
•Bioluminescence - light produced by a living organism
•Fluorescence - when light is absorbed and re-emitted at a different wavelength
•Phosphorescence - when energy is absorbed and re-emitted but over along period of time
✴These are all examples of COLD light
Luminescence
Bioluminescence
•Used in 90% of deep sea organisms and a few terrestrial organisms
•Used to find prey, hide, and communicate
•Mostly blue and green but some red light as well -- Why?
Uses for Bioluminescence
Counterillumination Use of red light to see prey
Lure preyStun or confuse predators or prey
Attract a mateCommunication
How does it work?
Enzyme
Luciferins
So...
We have seen how organisms can use
luminescence...
How can we use luminescence?
Luminol• Used by crime scene
investigators to detect blood
• The iron in blood acts like a catalyst to activate luminol, producing light
• Helpful in finding blood that may have been cleaned up because traces are left behind
• Bleach will react with luminol, showing if cleaning product has been used
Green Fluorescent Protein
• Aequorea victoria
• Aequorin is the protein, which emits blue light when bound with calcium
• GFP absorbs the blue light and makes it green under UV light
• Osamu Shimomura, Marty Chalfie and Roger Tsien received the Nobel Prize in Chemistry in 2008 for their work with GFP
• Used so we can see where proteins are made and where they end up
• helpful in cancer, Alzheimer’s, and HIV research
Brainbow