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Fixing the cells for FACS - Paraformaldehyde or Formaldehyde (Sep/24/2010 )

Hello All,

When I searched for purchasing the product Paraformaldehyde, I got several results with 'Formaldehyde'. What is the difference of using each of them?

My purpose id for fixing the cells for FACS. Can either of them be used?



This is a common issue about paraformaldehyde and formaldehyde. According to my own experience there is no difference. It doesn't matter which one. But if you want to do FACS then better use absolute or 70% ethanol. It should be freezing cold at about -20C. Most FACS methods use EtOH. I don't know why but I don't want to risk fixing with formaldehyde to find out.


Ethanol fixation is suitable ONLY for DNA content and intranuclear staining and not compartible with surface staining performed before the fixation is done.
Formost IC protocolthe best way is to use PF (or ready-to-use fix/perm kits from BD or eBioscience. Nice dotplots cost a lot :))

-Denis Baev-