Hi experts!

I'm looking for a way to deliberately bleach fluorophores (e.g. FITC, Alexa
488 and Cy3) completely in a sample.

I have some rather rare specimens that I have incubated with two different
primary antibodies (these were in turn labeled with corresponding secondary
antibodies). Now I'd like to label the same specimens a third and fourth
time with different primary antibodies. I don't really need simultaneous
labeling with the first two. Since I've run out of additional laser lines
and different fluorophores, I'd like to (1) bleach the fluorophores of the
first labeling completely but retain the possibility to incubate with new
markers afterwards and (2) perhaps block the remaining binding sites of
primary antibodies of the first incubation. Is there any way to do so except
by photobleaching?

Thanks in advance for any suggestions!

Rene




__________________________________________________
Dipl. Biol. Rene Hessling
Universitaet Osnabrueck
Spezielle Zoologie
Barbarastr. 11
D-49069 Osnabrueck
Germany

Tel. ++49-541-969-2859
Fax. ++49-541-969-2587
http://www.biologie.uni-osnabrueck.de/spezzoo/Hessling/index.html
__________________________________________________