Dear Histonetters,

There are truly lots of rumours running around as to the best way to store
antibodies. In my experience, antibodies have proven to be actually very
stable, if you except monoclonal IgMs, which are really very difficult to
handle.

I store most of my antibodies at -20°C, but diluted 1/4 and containing 60%
glycerol. The glycerol prevents freezing, which allows taking small amounts
without having to thaw/freeze. Also, should your freezer have a bad day and
freeze down lower than -30°C (bad things happen in the real world !!), the
glycerol will protect the antibody during the freeze. I have stored
antibodies in this way for 15 years now without seeing any loss in the
efficiency of the antibodies.

The thing to avoid at all cost are freeze/thaw cycles. These will damage
your antibody antitime !!! Diluted antibodies stored at 4°C with sodium
azide often can be very stable. I have used an anti-ankyrin antiserum
diluted 1/200.000 for Western blotting. This diluted had already been used
several times when fungi appeared. As we had no further stock antiserum, we
sterilized the antiserum by filtration, and have used the diluted batch for
several more months. Now this was probably a very fortunate event, but I
think that if you avoid freeze/thaw cycles and have a good antiserum
(obtained after several boost and thus containing mostly IgG), you should
be able to store them glycerolized at -20°C for several years without
loosing activity, even for perox or alk-phos conjugates. With monoclonal
antibodies, the outcome depends on the isotype: IgGs are very stable, but
IgM .......

Paul
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Paul Klosen, PhD
CNRS UMR 7518 Neurobiologie des Fonctions Rythmiques et Saisonnieres
Universite Louis Pasteur
12, rue de l'Universite
F-67000 Strasbourg, FRANCE
Tel. 03.88.35.85.04
Fax. 03.88.24.04.61
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