Hi all,
I was told once that there are no stupid questions, so let's test that 
assumption.

The question has to do with photobleaching vs. excitation energy.  To get X 
photons from a fluor, would there be less photobleaching using a single 
wavelength excitation source at peak excitation wavelength, or a broadband 
(20-30nm) light source centered on the peak excitation of the molecule, or 
would there be no difference?  My assumption is that lower "power" 
(brightness?) would be needed for the broadband source, but would the 
overall photon flux be greater to get equivalent output?

To take this one step farther, is there less or more bleaching from 
"inefficient" excitation, i.e. off-peak excitation, to get the same output? 
If a fluor is less efficiently excited, is it less efficiently bleached, 
even though more power may be needed to get equivalent output?

 Thanks,
Carl

Carl A. Boswell, Ph.D.
Molecular and Cellular Biology
University of Arizona
520-954-7053
FAX 520-621-3709