Freezing cells in blocking buffer? Urgent! - (Jan/17/2007 )

Hi all,
I am performing immunofluoresce experiment. I fixed the cells in paraformaldehyde and pemeabilized the membrane with TritonX. Afterwards I continue with blocking the cells with PBS (2%BSA and 0.1%TritonX-100).
My question is: What will happen if I keep the cells overnight in this blocking buffer at -20. Can I continue next day or sth would happen to the cells.
I would be very glad for the answers.
Thank you very much
Cheers

I would leave the cells in blocking buffer in 4C. Some times for upto 10 days.

I have never left cells in blocking in -20C.

Crystals could form and might damage the cells such that the cellular morphology could b affected.

But honestly, I am not sure. IF u have the cells in -20C, just go ahead and complete it and observe how the cells looks like. might tell us something.

In my experience cell freezing leads to very high background fluorescent signal, I don't recomend you do it under PFA-fixation conditions. If you want to save your sample you can leave it at RT or 4 0C overnight and even longer without any troubles. Usually I stain cells overnight at 4 0C and have very law background

So here comes the result of the experiment.
The cells frozen in blocking buffer can be nicely processed afterwards and analyzed by immunofluorescence.
But one thing I did was to rapidly thawing them at 37C incubator so that no crystals form.
Thanks to all for the ideas.
Cheers

Good to know it worked.

enjoy !!!