[3dem] Virus on Carbon

[Ben Hankamer]

Hi Luiza
We have had similar problems with a number of proteins. What worked for us in some cases was to reduce the glow discharge time. It will depend on your set up but try down to 1 sec. 

The rational was to make the carbon sufficiently hydrophilic to allow the ice sheet to form properly in the holes of the holey carbon film, but to minimize electrostatic attraction of the proteins to the carbon. 

Ben

> On 13 Mar 2014, at 4:42 pm, "Luiza Mendonça" <luiza at caltech.edu> wrote:
> 
> Dear colleagues,
> 
> I work with HIV particles and (at least in my samples), they like the carbon film on the grids much better than the holes, but for me this is a big problem, as, even using high titer preps, they rarely go to the holes, resulting in less-than-perfect tomograms. Has anyone else had this problem? What did you do to solve it?
> My particles are resusspended in PBS (with gold fiducials) at the time of freezing.
> 
> Best,
> Luiza.
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