[3dem] Gatan 910 multi specimen cryo transfer holder-- not for the neophyte
Tomohiro Nishizawa
t-2438 at bs.s.u-tokyo.ac.jp
Wed Oct 3 04:19:00 PDT 2018
Dear Valorie,
Thank you so much for the information.
I also asked Gatan, and they say thy are also developing a new
multi-specimen holder based on the Elsa holder, though I am not sure how
good it will be.
Again, I appreciate for your kind response.
Tomohiro,
On 2018/10/02 21:03, Bowman, Valorie D wrote:
> Dear Tomohiro,
>
>
> Yes, that problem is corrected. They no longer sell the version I
> described.
>
>
> The only problem with the version they sell now is the potential to
> accumulate more frost during the time it takes to load 3 grids and the
> resulting longer wait for it to stabilize in the column prior to
> imaging. However, since it's often used for screening freezing
> conditions rather than data collection, it's well worth it.
>
>
> *Cheers,*
> /
> /
> /Valorie
> /
> /
> /
> /Valorie Bowman/
>
> vdb at purdue.edu
> 765-494-5643
> EM Facility Laboratory Manager/
> Senior Research Electron Microscopist
> Purdue Cryo EM Facility
> Purdue University
> ------------------------------------------------------------------------
> *From:* 3dem <3dem-bounces at ncmir.ucsd.edu> on behalf of Tomohiro
> Nishizawa <t-2438 at bs.s.u-tokyo.ac.jp>
> *Sent:* Tuesday, October 2, 2018 4:33 AM
> *Cc:* 3dem at ncmir.ucsd.edu
> *Subject:* Re: [3dem] Gatan 910 multi specimen cryo transfer holder--
> not for the neophyte
> Dear all,
>
> I found previous posts on Gatan multi-specimen cryo holder 910.
> We are now considering purchasing this holder and am curious about the
> current situation. Were all these problems already fixed?
> Any information is greatly appreciated.
>
> Best,
>
>
> Tomohiro Nishizawa
> University of Tokyo
>
>
>
>
> On 2017/11/01 0:17, Matthias Wolf wrote:
>> Dear Valorie,
>>
>> Thank you very much for your detailed reply. This is indeed very helpful.
>>
>> But I don’t fully understand the anatomy of he holder - When you talk
>> about the “cassette”, what exactly do you mean? From the brochure it
>> looks just like a 626 with 3 wells at the tip of the holder rod, into
>> which a naked grid is loaded directly and secured by split ring
>> (presumably a more “springy” version of the ring used in the 626).
>> This would be consistent with your “old design”. Does the entire tip
>> of the holder come off?
>>
>> Or are you loading assembled FEI cartridges (ring, grid, C-clip)
>> unsecured onto the holder and those can fall out?
>> Their height would probably be too thick for locking them down with
>> the split ring. I remember that silicon nitride grids, which are about
>> 0.4 micron thick, could barely be clipped in the 626.
>> If so, is there a dedicated version of the 910, which is designed to
>> take FEI cartridges (the “new design”)?
>>
>> Also, how many hours of working time do you get before refilling the
>> dewar?
>> Is a movie rate camera required for drift compensation at anything but
>> low mag?
>>
>> Thanks, Leo, for pointing out a newer model - I will inquire.
>>
>> Best regards,
>>
>> Matthias
>>
>> On Oct 31, 2017, at 21:37, Bowman, Valorie D <vdb at purdue.edu
>> <mailto:vdb at purdue.edu>> wrote:
>>
>>> Dear Matthias,
>>>
>>>
>>> We have one. It is both great and terrifying. I have used it to
>>> screen 6 cryo conditions in an afternoon. BUT, it has one awful
>>> design flaw- it is incredibly easy to drop the cassette into the
>>> column. If a person is looking at the 3rd grid and turns the grid
>>> selector the wrong direction, & plop! Gravity immediately pulls the
>>> left end of the cassette down off the edge of the stage, the right
>>> end pivots up off the ball on the end of the rod, and the whole
>>> thing falls out into the abyss.
>>>
>>>
>>> We have one of the older models, and that design was far superior.
>>> Loading was more difficult, but this risk does not exist with the
>>> grids mounted in wells in the sample rod itself.
>>>
>>>
>>> Both models take 15-20 minutes longer to stabilize in the microscope
>>> after insertion, and they take longer to cool down, but I count that
>>> a fair trade off for 3 samples at once. The split-ring clip rings
>>> are not too different from the 626 version; it's just easier to
>>> accidentally push through a grid.
>>>
>>>
>>> By far, the worst thing is the lack of a real "lock" onto
>>> the cartridges. This holder was tested by one of our best people,
>>> and he dropped the cartridge in the scope the very first time he used
>>> it! I know it is only a matter of time before it happens again-- and
>>> the cartridges are not cheap, plus potential scope down time if
>>> it blocks the beam, pole pieces, etc.
>>>
>>>
>>> It's a great holder, but if you have a wide range of levels of users,
>>> it might not be one for everyone.
>>>
>>>
>>> Valorie
>>>
>>>
>>> /Valorie Bowman/
>>>
>>> vdb at purdue.edu <mailto:vdb at purdue.edu>
>>> 494-5643
>>> EM Facility Laboratory Manager/
>>> Senior Research Electron Microscopist
>>> Purdue Cryo EM Facility
>>> Purdue University
>>> ------------------------------------------------------------------------
>>> *From:* 3dem <3dem-bounces at ncmir.ucsd.edu
>>> <mailto:3dem-bounces at ncmir.ucsd.edu>> on behalf of Matthias Wolf
>>> <matthias.wolf at oist.jp <mailto:matthias.wolf at oist.jp>>
>>> *Sent:* Monday, October 30, 2017 11:00 PM
>>> *To:* 3dem at ncmir.ucsd.edu <mailto:3dem at ncmir.ucsd.edu>
>>> *Subject:* [3dem] Gatan 910 multi specimen cryo transfer holder
>>>
>>> Hi all,
>>>
>>> We are considering the purchase of a Gatan 910 cryo transfer multi
>>> specimen side entry holder.
>>>
>>> Does anyone have experience with this holder?
>>>
>>> The specs with respect to stability are identical to the 626 (the
>>> alternative), but I don’t know how it will perform in practice. It
>>> can take 3 grids.
>>>
>>> The holder will be used for screening of a larger number of cryo
>>> samples. Cryo tomography is not a requirement. Due to possible
>>> contamination during unloading, the idea is not to reuse screened
>>> grids – once plunging conditions are established, a second grid
>>> frozen under identical conditions on a reproducible plunging bot will
>>> be used for data collection on a higher end cryo TEM with DED and
>>> autoloader. We hope to accelerate the cryo screening by loading 3
>>> grids at once instead of one at a time and to reduce frosting and ice
>>> contamination with less cryo transfers. This step aims at offloading
>>> screening from the expensive high end tools and to maximize their
>>> beam time for productive data collection. The holder will also be
>>> used at room temperature for negative stained samples before cryo
>>> screening, both of which will act as triage steps for samples of
>>> insufficient quality.
>>>
>>> Matthias
>>>
>>
>>
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