[ccp4bb] Freezing under oil

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Scientific programmer to work on iMosflm at MRC LMB, Cambridge UK
From: A Leslie andrew {- at -} MRC-LMB {- dot -} CAM {- dot -} AC {- dot -} UK
Date: 2010-02-04

Next message:
Subject: Re: Freezing under oil
From: Vellieux Frederic Frederic {- dot -} Vellieux {- at -} IBS {- dot -} FR
Date: 2010-02-04

Subject: Freezing under oil
From: Claudia Scotti claudiascotti {- at -} HOTMAIL {- dot -} COM
Date: 2010-02-04

Dear list,

I'm trying to freeze crystals in cryoconditions containing the following:

0.1 M Sodium acetate pH 4.4

2.15-2.3 M Ammonium sulphate

7% n-butanol

15% glycerol

The problem is that the crystals (beautiful hexagonal prisms) seem to shatter in a random fashion: some are unaffected, some, coming from the same drop, disgregate miserably. One even split into three parts, of which two disgregated and one survived perfectly well.

I've tried both by moving the crystals directly in the cryocondition and by progressively increasing the glycerol concentration to no avail.

Shall I just select those that survive?

I was wondering if anybody has ever had this same problem and if freezing under oil could be an alternative. If yes: any suggestions on how to fish the crystals? I tried it in the past, but I found it very difficult...

Experiences and suggestions are welcome.

Claudia

Claudia Scotti Dipartimento di Medicina Sperimentale Sezione di Patologia Generale Universita' di Pavia Piazza Botta, 10 27100 Pavia Italia Tel. 0039 0382 986335/8/1 Facs 0039 0382 303673

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CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Scientific programmer to work on iMosflm at MRC LMB, Cambridge UK
From: A Leslie andrew {- at -} MRC-LMB {- dot -} CAM {- dot -} AC {- dot -} UK
Date: 2010-02-04

Next message:
Subject: Re: Freezing under oil
From: Vellieux Frederic Frederic {- dot -} Vellieux {- at -} IBS {- dot -} FR
Date: 2010-02-04