Liquid nitrogen, mouse spleen Re: [Histonet] Freezing tissues

Gayle Callis gcallis <@t>
Thu Jan 4 10:27:19 CST 2007

Yes, your very last suggestion will work perfectly.  We place a plastic 
petri dish IN the liquid nitrogen, then you can set the OCT embedded spleen 
in the petri dish.  We have shattered spleen and if we do isopentane cooled 
by liquid nitrogen, or direct immersion into liquid nitrogen.  Just make 
sure the petri dish is supported so it does not tip over in the Liq N2, and 
do not allow Liq N2 into the dish.  You need to replenish the liq nitrogen 
as it is important to maintain the dish directly in the N2.  In other 
words, the dish goes canoeing in the Liq N2.

Good luck

At 03:08 AM 1/4/2007, you wrote:
>Hi there,
>I need to freeze some mouse spleens tomorrow for cryosectioning. Usually
>I cut the spleen in half and place it in OCT in a foil mould. I then
>place the foil mold in a petri dish of isopentane sitting on dry ice.
>This seems to work well and I dont have problems with ice crystals or
>freezing artifacts. However, after the holidays there is not a drop of
>dry ice to be found in our institute so I need some advice on another
>method - possibly using liquid nitrogen. I've read a number of methods
>whereby you immerse the tissue directly in the LN, hold the tissue in
>the LN vapours or do as I do with isopentane but have the petri dish
>floating on LN (is this possible?).
>Any suggestions greatly appreciated!
>Histonet mailing list
>Histonet <@t>

Gayle Callis
Research Histopathology Supervisor
Veterinary Molecular Biology
Montana State University - Bozeman
PO Box 173610
Bozeman MT 59717-3610
406 994-6367
406 994-4303 (FAX)

More information about the Histonet mailing list