It was my understanding that Mitegen plastic capillaries only work for
crystal evaluation, since they are permeable enough to cause crystal to
dry up within few hours - hopefully that is enoug time to get a complete
dataset, but one should be concerned about changes in unit cell
parameters as crystal shrinks upon progressive dehydration. But maybe
that changed.
I have successfully collected data on capillary-mounted crystals in
cryostream in the past - had no problems with ice formation on the
capillary itself. Maybe the warm flow is malfunctioning - do you have a
general problem of crystals ultimately icing up even when loop mounted?
You may want to bump up the cryoprotectant, as the cooling will be
definitely slowed down.
Good luck,
Ed.
On Thu, 2011-02-17 at 17:03 +0000, R Conners, Biochemistry wrote:
> Dear all,
>
> We are working on a Category 3 protein which must be contained so we have
> our crystals mounted in a loop and then covered with a plastic Mitegen
> cover which is glued in place. We're currently collecting at room
> temperature, but wondered if anyone has any experience of using a contained
> system at low temperatures? Any attempts I've had so far at freezing
> through either the plastic or a glass capillary have resulted in formation
> of ice on the surface so it is not even possible to see the crystal to
> centre it.
>
> Best wishes,
>
> Becky
>
> -------------------------------------------------
> Dr Becky Conners
> School of Biochemistry
> University of Bristol, UK
>
> http://www.bris.ac.uk/biochemistry/brady
> [log in to unmask]
> 0117 3312149
--
Edwin Pozharski, PhD, Assistant Professor
University of Maryland, Baltimore
----------------------------------------------
When the Way is forgotten duty and justice appear;
Then knowledge and wisdom are born along with hypocrisy.
When harmonious relationships dissolve then respect and devotion arise;
When a nation falls to chaos then loyalty and patriotism are born.
------------------------------ / Lao Tse /
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