STEM workshop
Illuminating Life: What's New and
Noteworthy in
Luminescence Spectroscopy and Imaging
Pat O’Hara
October 3, 2009
Emission of Light
YES
After heating?
Incandescence
NO
Luminescence
After excitation with sound?
After using mechanical forces?
YES
YES
Sonoluminescence
Triboluminescence
After excitation with light?
Immediately?
YES
fluorescence
YES
NO
Inanimate?
NO
phosphorescence
YES
chemiluminescence
NO
bioluminescence
What is fluorescence?
http://micro.magnet.fsu.edu/primer/
Fluorescence is the emission of a
photon by an excited state molecule.
What’s new in fluorescence?
• Fluorescence of gemstones used to detect
fake diamonds
• Fluorescence is key to spider sex in some
species
• Fireflies chemiluminescence
• Deep Sea Bioluminescence• Bananas that glow: Fluorescence of ripening
fruit is key to cellular processes
Beware jewel theives!
Real diamonds fluoresce
http://www.sciencemag.org/cgi/reprint/315/5811/481.pdf
http://www.sciencemag.org/cgi/reprint/315/5811/481.pdf
Fluorescence of Plants
• Ultraviolet fluorescence
of plants is detected by
bees, who have
photoreceptors in this
region of the spectrum
and can see what looks
to us like landing
patterns on the petals
directed towards pollen
Emission of Light
YES
After heating?
Incandescence
NO
Luminescence
After excitation with sound?
After using mechanical forces?
YES
YES
Sonoluminescence
Triboluminescence
After excitation with light?
Immediately?
YES
fluorescence
YES
NO
Inanimate?
NO
phosphorescence
YES
chemiluminescence
NO
bioluminescence
What is chemiluminescence?
• Chemical reaction results in an intermediate
that is in an excited state.
• Reaction goes to product after this
intermediate releases a photon
• Energy of the photon comes from chemical
energy due to the difference in energy of
reactants and products
What is Chemiluminescence?
Example 1: Chemistry of Lightsticks
Phenol + CO2 + Dye + Light
What is Chemiluminescence?
Example 2: Chemistry of the Luminol Reaction
Oxidants: Peroxide, bleach, hemoglobin
light
3-aminophthalhyrazide
Catalysts: sodium perborate, cupric chloride
Emission of Light
YES
After heating?
Incandescence
NO
Luminescence
After excitation with sound?
After using mechanical forces?
YES
YES
Sonoluminescence
Triboluminescence
After excitation with light?
Immediately?
YES
fluorescence
YES
NO
Inanimate?
NO
phosphorescence
YES
chemiluminescence
NO
bioluminescence
Firefly Bioluminescence
What is Bioluminescence?
Chemistry of the Luciferase Reaction
• In the dark cycle (quiescent) oxygen is consumed by mitochondria (green) and ATP
and luciferin are stored up in peroxisomes.
• In the flash cycle, (NO) is released, and prevents consumption of O2 by
mitocondria. Instead, O2 diffuses to peroxisome and voila! A flash!!
What is Bioluminescence?
Chemistry of the Luciferase Reaction
The luciferase catalyzes the oxidation of luciferin
Resulting in light and an inactive "oxyluciferin"
Luciferase
•
•
http://srv2.lycoming.edu/~newman/courses/bio43799/luciferase/index.html
luciferase
Bioluminescence from surface water
Animal------Jellyfish near surface
Small algae called milky sea
Bioluminescence from mid-water range
Let’s see video clip……….
Mid-water … 500-2000 ft deep
light intensity decreases
exponentially
250 ft 10% less than surface
500 ft 1% less than surface
Plants can not photosynthesize
Why do organisms emit this light?
1. defense against predators
2. camouflage
3. see things and find food
4. communicate
http://www.biolum.org/
Giant Squid- caught in action in 2007
•http://news.bbc.co.uk/2/hi/science/nature/6357005.stm
Bioluminescence from deep sea jellies
http://www.youtube.com/watch?v=ubIg-WtjUg0
Green Fluorescent Protein GFP
GFP is a small very fluorescent protein isolated from the
bioluminescent jellyfish, Aequorea victoria. This protein glows or
fluoresces green when it absorbs blue light emitted from another
protein in the jellyfish, aqueorin.
http://www.bio.davidson.edu/courses/genomics/method/GFP.html
Fluorescent Bomb Throwing
Marine Worm
“fast, agile swimmers with glistening, translucent
bodies sprouting rows of bristles that work like
paddles. When disturbed, they eject glowing,
green blobs that probably serve as decoys to
distract predators’”
http://www.bio.davidson.edu/courses/genomics/method/GFP.html
Pat’s Picks
• Bizarre deep ocean sea creatures:
• Deep sea luminescent animals:
– http://www.youtube.com/watch?v=wnStTpupI2s&mode=related&search
– http://www.youtube.com/watch?v=70c-g0j5Qcc
– http://www.ted.com/talks/lang/eng/david_gallo_shows_underwater_astonis
hments.html
• UCSB links:
http://www.lifesci.ucsb.edu/~biolum/organism/milkysea.html
Milky Sea Captured on Satellite Image
off coast of East Africa
Glowing bananas:
photo credit: Zina Deretsky, National Science Foundation
Glowing bananas:
photo credit: Zina Deretsky, National Science Foundation
Your Banana Challenge
• I’ve brought in two dozen bananas of various
stages of ripeness, some common solvents,
knives, jars, and a black light.
• I’d like us to explore this phenomenon and put
together some discovery lab questions that –
with a black light and a ripe banana, might be
useful to you in your lab.