> I have read the warnings to only use "fresh" parformaldehyde for fixation, but I
> don't recall ever hearing why.
> Could someone explain the sorts of artifacts that old paraformaldehyde will
> introduce? And what exactly IS old?
Good Question.
We make up a 2%pf solution in PBS and keep that in the dark, 4'C. When
needed, we make up the working (user) solution of a 1% pf in PBS - this
1% we make up fresh each time. HOwever, the 2% stock has been made and
stored for up to whenever we need to make it again. That has often been
as much as 6 months.
David
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+ David L. Haviland, Ph.D. Internet:"haviland@kids.wustl.edu" +
+ Washington Univ. School of Med. A.K.A : The Compiler +
+ Dept. of Peds./Pulm. Box 8116 ICBM-Net : Just hit St. Louis +
+ 400 S. Kingshighway &-6 <- User is Brain Dead... +
+ St. Louis, MO 63110 FAX: 314-454-2476 +
+ (314) 454-6076 +
+ ------------------------------------------------------------------- +
+ Will clone and sequence genes for food. +
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