Rajesh,
Why not try a soak-in-place by adding iodide and/or cryoprotectant
directly to the crystallization drop? Then you only have to fish out the
crystal once, minimizing handling. I usually do this by preparing an
artificial mother liquor solution that has 125% of the final desired
concentration of cryoprotectant and/or ligand. Add 4 volumes of this
solution to your crystallization drop all at once or in stages. (I
usually add 0.25, 0.25, 0.5, 1.0, and 2.0 drop volumes a few minutes
apart). The drop can be incubated over its reservoir well during this
procedure between additions to minimize evaporation. This often works
well for fragile crystals or crystals that are sensitive to evaporation
of the drop.
Cheers,
_______________________________________
Roger S. Rowlett
Gordon & Dorothy Kline Professor
Department of Chemistry
Colgate University
13 Oak Drive
Hamilton, NY 13346
tel: (315)-228-7245
ofc: (315)-228-7395
fax: (315)-228-7935
email: rrowl...@colgate.edu
On 5/3/2012 9:51 AM, Rajesh Kumar wrote:
Dear All,
I have very thin crystals but diffracting. I was not able to handle
them easily for iodide soak. I always lost the crystals during
manipulation and other big crystals obtained after
seeding doesn't even give any diffraction. I tried for
co-crystallizing with NaI. The crystals appear only up to 20 mM in 1:2
(3ul drop of 1 ul protein and 2ul reservoir).
Is this concentration of iodide is enough for SAD data ( if it had
good incorporation) ?
I appreciate your help.
Thanks
Rajesh
