[Histonet] Fresh vs. frozen paraformaldehyde

[Barlow, Gillian]

Dear Histonetters

Please solve an ongoing debate for our perfusions!  I was always told that
4% paraformaldehyde should be made fresh each time before using, at max made
the evening before and stored at 4 degrees to use the following morning.
However, somebody from another lab says they make theirs in bulk and freeze
what they dont use, thawing and refreezing as necessary.  Is this ok to do?
They also say they use 10% neutral buffered formalin for their perfusions if
they dont have 4% PFA. 

Many thanks 
Gillian
Gillian Barlow, PhD
Postdoctoral Fellow
Laboratory of Julie Korenberg, PhD, MD
Cedars-Sinai Medical Center
Davis Bldg, Lab 2007
110 George Burns Rd
Los Angeles, CA 90048

Phone: (310) 423 7650
Fax: (310) 423 0302
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