Re: CO2 grade for on-scope incubator?

Posted by Teng-Leong Chew-2 on
URL: http://confocal-microscopy-list.275.s1.nabble.com/CO2-grade-for-on-scope-incubator-tp7582397p7582415.html

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Hi Peter,

Kurt is right. You need humidity to minimize evaporation from
the culture medium or that will drastically alter the osmolarity
of the medium very quickly. That¹s why there is a tray of water
at the bottom of your regular cell culture incubator. Apparently
the effect from the carbonic acid level is miniscule.

You don¹t need the bone dry CO2.

Regards,
Leong

--
Teng-Leong Chew, PhD
Director, Advanced Imaging Center
Howard Hughes Medical Institute at Janelia
Ashburn, VA 20147







On 7/22/14, 7:42 PM, "Peter Werner" <[hidden email]> wrote:

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>
>At our facility, we have a spinning-disk confocal system, with an
>incubator that surrounds the entire stage and substage area. The
>question I have concerns the type of CO2 I should be using for the
>incubator. I was told by someone from the UC Berkeley Biological Imaging
>Facility that I should be careful about the grade of carbon dioxide that
>I use - apparently, it should be high purity and as low as possible in
>H2O. The reason is, even if the cell cultures themselves will be fine
>with a lower purity of CO2, CO2 forms carbonic acid in reaction with
>water, and the acidified water content in the chamber atmosphere can be
>damaging to the instrument over the long term, hence, the less H2O mixed
>in with the CO2, the better. If this is the case, that would imply that
>"Instrument Grade" or "Bone Dry" grades would be what I need to use.
>
>I was wondering if anybody else knew of this recommendation and followed
>this practice. It makes sense to me why one would want to minimize
>carbonic acid formation in environments the confocal system is exposed
>to. On the other hand, it does entail some expense, not so much in terms
>of the gas itself, but in terms of special cylinders for high-purity
>CO2, which must be rented, or purchased at $500+ per gas cylinder.
>
>Let me know,
>Peter G. Werner
>Instructional Assistant/Lab Technician, Microscopy, Merritt College
>SEM/AFM Lab Technician, Ohlone College
>[hidden email]