Dear Confocalists,

      A colleague of mine is trying to label sperm (sea urchin)
with a fluorescent dye so as to label specific eggs that the
sperm have fertilized.  As such the dye would need to:
a) be non-toxic
b) cross membranes for loading via bath application
c) label the nucleus (since the sperm nucleus is what enters
     the oocyte)
d) be well retained once inside cells.
e) dual labeling at 2 different wavelengths would
     be great, but Steve would settle for one at this point.
He's already tried DAPI and acridine orange, which haven't
worked for different reasons.  I've suggested fluorescein
diacetate and oregon-green AM.  Any other suggestions
would be appreciated.   If you prefer to reply off line, you
can email me at: [log in to unmask]
or, if you'd like, you can email Steve Palumbi directly at
[log in to unmask]

Best Regards,
Don O'Malley
Northeastern University