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<P><FONT face=Arial><FONT size=2>In a message dated 10/24/2003 3:01:17 PM US
Mountain Standard Time, <SPAN class=489304604-29102003>
</SPAN></FONT></FONT><FONT face=Arial size=2><A
href="mailto:Bonnie.P.Whitaker@uth.tmc.edu">Bonnie.P.Whitaker@uth.tmc.edu</A>
writes:</FONT></P>
<P><FONT face=Arial><FONT size=2>> I have a question for you guys: A
researcher here in OB/GYN is doing<SPAN
class=489304604-29102003> </SPAN>rhodamine-labeled fluorescent work (he
didn't say what antibody) on mouse fallopian tube... he thought he was
having a staining problem, <SPAN class=489304604-29102003> </SPAN>but
has determined that his tissue is auto-fluorescing. The tissue is frozen
in<SPAN class=489304604-29102003> </SPAN>OCT<SPAN
class=489304604-29102003> </SPAN>and fixed in acetone/methanol. What can he
do to quench this<SPAN class=489304604-29102003>?</SPAN> <SPAN
class=489304604-29102003><</SPAN></FONT></FONT></P>
<P><FONT face=Arial><FONT size=2><SPAN class=489304604-29102003>A couple more
thoughts Bonnie... </SPAN></FONT></FONT></P>
<P><FONT face=Arial><FONT size=2>Rhodamine is excited with 488nm (blue light). I
am assuming the system used in this case employs such a light source. Most
organic material fluoresce under 488nm excitation. The best option is to use a
narrow bandpass filter (20-40nm bandwidth centered about the peak emission
wavelength of the dye). This will not completely eliminate autofluorescence but
it will greatly reduce it.<SPAN class=489304604-29102003> </SPAN>Another
possibility is to image the tissue before and after staining to see the
difference. Then could subtract one image from the other<SPAN
class=489304604-29102003>...</SPAN></FONT></FONT></P><FONT face=Arial size=2>
<DIV align=left><FONT face=Arial size=2>Glenn Smith, P.Eng.</FONT></DIV>
<DIV align=left><FONT face=Arial size=2>519.886.9013 x38</FONT></DIV>
<DIV align=left><FONT face=Arial size=2><A
href="mailto:gsmith@confocal.com">gsmith@confocal.com</A></FONT></DIV>
<DIV align=left><FONT face=Arial size=2></FONT> </DIV>
<DIV align=left><FONT face=Arial size=2>Biomedical Photometrics
Inc.</FONT></DIV>
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