Re: aliquoting 4% formaldehyde

Posted by Martin Wessendorf-2 on
URL: http://confocal-microscopy-list.275.s1.nabble.com/aliquoting-4-formaldehyde-tp7585663p7585664.html

***** To join, leave or search the confocal microscopy listserv, go to: http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy Post images on http://www.imgur.com and include the link in your posting. ***** Dear Doug--

My understanding is that if you cool solutions containing formaldehyde gas, you accelerate its re-conversion back to paraformaldehyde. 
However, I don't have a reference for this at my fingertips. 

--Did the solution freeze solid?  If so, the solubility of FA gas might've decreased when the phase changed and you might've lost some, but that's a guess. 

Good luck!

Martin Wessendorf

On 9/20/2016 9:34 AM, Cromey, Douglas W - (dcromey) wrote:

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I was talking with a student yesterday about their cells which did not look particularly good under the microscope. The discussion eventually came around to fixation. The student told me that he made up some 4% formaldehyde fixative and then froze back (20 deg C) aliquots for later use. This was something he had seem on an online research forum. In my fairly lengthy experience I have never heard of this being done and I am suspicious that this is NOT a good idea. Thoughts?

 

Doug

 

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