You can try microseeding. It is really suitable for crystallization in high ammonium sulphate. I got a similar problem as well, before. Microseeding can supply nucleus. You can get more crystals and spend less time.
And for the salt crystallization, I think if you transfer quickly it can be fine. Or a high humidity might be useful. Liang On Tue, 4 Nov 2008 19:34:20 +0100, Sabine Schneider wrote > Hi everyone, > > We got crystals that grew in ~3.2M ammonium sulphate and some > tris-buffer at 18dgC. Unfortunately the crystals take a while to grow > (~4-5 weeks) and so far we only have 4-5 xtals. I tried to freeze > the crystals, but as soon as I broke though the skin of the drop the > ammonium sulphate started to crystallise. I got the crystals out, > froze them using sort of an artifical mother liquor with sodium > malonate as cryo and tested the diffraction. The freezing seems to > be OK and it is definitely a protein crystal. The crystal suffered > when the ammonium sulphate in the drop started to crystallise, but > didn't seem to deteriorate anymore in the cryo. Well the corners had > already more or less disappeared by the time I got them out of the drop... > Since we only have a few xtals at the moment and I can't try out a > lot of things, I was wondering if anyone has experienced and solved > a similar problem? My freezing attempt so far was in an > airconditioned room with 18dgC. I thought about higher humidity and > temperature in the room, and/or adding the cryo directly to the > drop.... Any ideas are very much appreciated! > > Sabine > > ------------------------------------------ > Dr. Sabine Schneider > Ludwig-Maximilians-University > Department of Chemistry and Pharmacy > Butenandtstrasse 5-13, Building F > 81377 Munich > Germany > Phone: +49 (0)89 2180 77846 > Fax: +49 (0)89 2180 77756 > http://www.carellgroup.de/ -- Open WebMail Project (http://openwebmail.org)
