Re: [ccp4bb]: Oils with Conventional Mounts

[Harry Powell <harry@mrc-lmb.cam.ac.uk>]

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> > 
> > On Tue, 30 Apr 2002, James Stroud wrote:
> > 
> > > Has anyone used oil to stabilize otherwise labile crystals for a
> > > conventional room temperature mount?
> >

I haven't tried the following with macromolecular crystals, but it struck
me that using oil for cryo-mounting is a technique borrowed from small
molecule (SM)  crystallography; for a room temperature mount for SM
crystals which won't take flash cooling but are air and moisture
sensitive, I have used epoxy resin glues (e.g. Araldite) in much the same
way as an oil (both for sticking the crystal into a loop and coating it); 
there are disadvantages (e.g. possible reaction between resin and crystal,
relatively slow setting times - I'm sure people can come up with other
ideas).

I guess you could also try "superglue" (polymethylmethacrylate?) which
sets more quickly, but my guess is that surface damage to a crystal coated
with it might prove the rule rather than the exception. 

ISTR that there is a whole section in one of the "old red" International
Tables on the subject - sorry, I don't remember which volume, and I don't
know if there's a similar section in the "new blue" ones.

Harry 
-- 
Dr Harry Powell, MRC Laboratory of Molecular Biology, MRC Centre, Hills
Road, Cambridge, CB2 2QH