> I am searching for some dyes in order to observe in vitro structures
> alive, and I dispose only of an Argon laser. I am thinking of the sytodyes
> generation of molecular probes for the nuclei. Does anyone have some
> experiency with them of with any other compatible with my purpose? And in
> that case, can you precise what is exactly its mechanism of action on
> the cell? (So how it maintains the biological structure alive?).

I started with Syto14 which very well peanatrated live cells and
bindes to DNA and RNA, so you clearly see the nucleus and most times
the RNA in the cytosol. However Syto14 was rather toxic to our cells
and two hours after using the dye all cells were dead. Then we
ordered the syto kit with dyes Syto11-16 and found out that our cells
only survived for 18h (our purpose) with Syto16, which can be used in
very low concentrations. Because we wanted to use this dye to follow
the process of apoptosis in time we needed such long working times.
However when you exite the dye with your laser or another light
source, than something is happening which can again cause cell death.
This is the point were we are now. I have done time measurements by
scanning one confocal section every 30 min. and sometimes my cells
servive, but most times my cells die by necrosis before the end of
the experiment.

Gert

 ========================================================================
Gert van Cappellen, [log in to unmask] Erasmus University,
Endocr.& Reprod., Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands
Fax: +31 10 4366832