I agree with Martin overall - we use a really big range of secondaries
(anti mouse / sheep / rabbit / rat conjugated to AMCA / Cy3 / Texas Red
/ Cy5 / FITC /biotin / Alexas etc). We have found consistently over many
years that you can get away with one freeze / thaw cycle as long as the
volume is small (eg up to about 5 microlitres), there is a bit of
glycerol in in the mix, and you use at least a -20C freezer.

IAN


Martin Wessendorf wrote:
>
> Tom Phillips wrote:
> >
> > The other big problem with -20 freezers is that they so often are
> > "frost-free" these days.  The auto defrost cycles on these types of
> > freezers are very tough on antibodies and sensitive enzymes.  I
> > believe Jackson recommends diluting their antibodies in 50% glycerol
> > if you want to store at -20 so that they don't "freeze" but yet are
> > kept cold.  I don't know if that limits the damage by a frost-free
> > freezer but do know that the molecular biology types all stress that
> > their enzymes diluted in glycerol are still very labile if stored in
> > a frost-free freezer.
>
> We typically store ours at -20 in glycerol and have no problems.  It's a
> good compromise, since you can pipette out just what you need.
>
> Martin
> --
> Martin Wessendorf, Ph.D.                        office: (612) 626 0145
> Associate Professor                             lab:    (612) 624 2991
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--
Professor Ian Gibbins
Anatomy & Histology
Flinders University of South Australia
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Australia

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