how to post fix frozen brain sections - (Jan/13/2014 )

I have human brain tissue frozen at -80 C.

I will be sectioning it using OCT and a cryostat so tissue will stay frozen while sectioning.

How do I go about fixing the sections?

Should I use PFA or formalin?

How long should the sections be fixed for?

Any info would be helpful!

for all intents and purposes. pfa becomes formalin when solubilized (see this wikipedia page).

so, if that is what plan to use then use formalin to fix.