antibody shelf life

<< Previous Message | Next Message >>
From:Gayle Callis <>
Date:Wed, 11 Aug 1999 14:27:04 -0600

Question:did she freeze, thaw, use, refreeze, thaw and use?  This damages
antibodies, and if you need to freeze down for future
use, aliquot antibody, store in a freezer (NO self defrost)  in
tight tubes, preferrably with o-ring caps.    We had 
aliquots dry out in flip top microcentrifuge tubes, switched to screw top.
This way you can take a tube out when you need it.  Never refreeze antibody.
Once thawed, you may want to centrifuge it a bit, to remove any protein 
aggregates that sometime show up after freeze/thaw. 

We also prefer  -80C storage, some antibodies can last for years.
You can also call tech services, and ask what they recommend for their 
products.  -27C storage is often approx a year.  Their spec sheets should
also give storage information.  We often exceed expiration dates on antibodies
never frozen.  (research area), they remain viable as long as they are stored
at 4C, and are handled with good clean technic (sterile pipette tips, kept
upright, pipetted and returned to refrig immediately.  They NEVER sit at
RT if so, put them on ice until you can pipette. We  have some that expired
3 years ago and still stain, were never frozen.  The small concentration of 
sodium azide helps if mfr uses it.  Know this sounds picky, but it also
keeps the cost of frequent replacement of antibodies to zero.    

Good luck and hope it helps
Gayle Callis 

<< Previous Message | Next Message >>