Chip,
 
My bet would be lipofucsins.  What kind of preparations are you using?
Perhaps a solvent extraction would remove them.  BTW, avian CNS has a few
neurons that autofluoresce very brightly at 568 nm, emitting >585 nm.
 
On Mon, 27 May 1996, Marshall (Chip) Montrose wrote:
 
> Hello colleagues.
>
>         Using the 543nm line of our Green HeNe laser, we have seen that our
> colonic tissue has a suprisingly bright autofluorescence at about 600-620nm.
> I am used to seeing autofluorescence in response to UV excitation (due
> to NADH and FADH), but this is the first time I have picked up
> autofluorescence at such red wavelengths. I have two items for discussion:
 
 
Regards,
 
Glen MacDonald
   Research Scientist
Hearing Research Laboratories of the
Virginia Merrill Bloedel Hearing Research Center
Box 35-7923
University of Washington
Seattle, WA  98195-7923
(206) 616-4156
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