INTRODUCTION TO FLUORESCENCE

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INTRODUCTION TO FLUORESCENCE (two-photon, three
steps, phase incoherent process)

• Einsteins coefficients, dipole transitions.
• Experimental setup
• T-configuration
• Jablonsky diagram
• Franck-Condon principle, reflection rule and
  Stokes shift
• Lifetime and quantum yield
• Fluorescence quenching (collisional)
• Londons theory of molecular forces
• RET resonant Energy Transfer
• FRAP (Fluorescence Recovery after Photo Bleaching

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Experimental setup
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Gregorio Webers T-configuration
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Stokes shift
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Protein Intrinsic Fluorophores
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stati di tripletto e di singoletto
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Kashas rule emission spectra are independent
of the excitation wavelength.
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Quantum yield Q and lifetime t
Gspectral emissivity, knr rate of non radiative
transitions
teoricamente
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Fluorescence Quenching
Collisional quenching
Stern-Volmer equation
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Fluorescence Anisotropy
anisotropy
polarization
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What is lost in steady state measurements?
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Green-fluorescent proteins GFP
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Non radiative energy transfer (RET)
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Center for fluorescence spectroscopy (J.
Lakowicz) http//cfs.umbi.umd.edu/ ISS
http//www.iss.com/ Fluorescence foundation
http//www.fluorescence-foundation.org/ Enrico
Grattons homepage http//www.lfd.uci.edu/gratton
/ Laboratory of fluorescence dynamics Gregorio
Weber http//www.lfd.uci.edu/weber/ CORSO DI
MICROSCOPIA OTTICA DI CLEGG http//online.physics.
uiuc.edu/courses/phys598om/spring12/