[3dem] Ethane ice on Vitrobot frozen grids

[Paul Keller]

Hello All,

I was wondering if anyone on the list had any insight into something I  
observe regularly when using our Vitrobot (Mk II); the formation of a  
layer of ethane ice on the grid during transfer from the liquid ethane  
cup into the outer ring and grid storage box.  The grid cannot then be  
used until the ethane ice is removed.

The ethane layer almost always seems to dissipate if I leave the grid  
in LN2 storage at least overnight, but this is not always desirable.   
Does anyone on the list have any advice for removing the ethane ice  
without damaging the underlying sample, or preferably, techniques for  
avoiding the formation of an ethane ice layer entirely?

Thank you,

-Paul Keller
Laboratory of Structural Biology Research
NIAMS, NIH
Building 50, Room 1504
50 South Drive MSC 8025
Bethesda, MD 20892-8025
301-451-4939
kellerp at mail.nih.gov