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Re: Freezing
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Dear Swami,
Yet another idea for freezing:
1. If your crystals are large enough, take a small loop and fish the
crystal such that the crystal is sitting on top of loop and _NO_
solution sticks to it anymore. I had such cases where I didn't need
any cryoprotectant at all simply because there is not water to freeze.
2. I just realized that very high salt concentrations also act as cryo-
protectants. I had saturated ammonium sulfate as precipitation agent
and for this crystallization condition I did not need any
cryoprotectant.
I do not know whether NaCl can be used in the same way, nor do I know
whether your crystals would stand a condition such as staturated NaCl
... but you can give it a try.
Good luck,
Pete
___________________________________________________________________________
Peter Burkhard
Abteilung Strukturbiologie
Klingelbergstr. 70
CH-4056 BASEL, Switzerland
Phone: ++41 61 267 20 91
Fax: ++41 61 267 21 09
E-mail: burkhardp@ubaclu.unibas.ch
> On Thu, 23 Sep 1999, Kunchithapadam Swaminathan wrote:
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>
> Dear :
>
> I have got a crystal and the condition is:
>
> 100 mM Tris-HCl, pH 7.5
> 150 mM Nacl
> 20 mM Ca Cl2
>
> (The crystal dissolves in conventional method of freezing, time course
> transfer in artificial mother liquor + 5%, 10%, 15%, 20%, 25% glycerol, MPD,
> PEG400). I am looking for suggestions/advice for freezing crystals grown in
> pure salt environment. Any tips?
>
> With regards,
> Swami
>
> ****************************************************************************
> Dr. Kunchithapadam Swaminathan Phone: (65) 873 2173 (H)
> Institute of Molecular Agrobiology (65) 872 7408 (W)
> The National University of Singapore Fax: (65) 872 7007 (W)
> 1 Research Link, Singapore 117604 Email: nathan@ima.org.sg
>
> Web: www.ima.org.sg/research/struct_bio/struct_bio.html
> ****************************************************************************
>
>