Re: fixable, dead cell nuclear counterstain.

Posted by Glen MacDonald-2 on
URL: http://confocal-microscopy-list.275.s1.nabble.com/fixable-dead-cell-nuclear-counterstain-tp7586389p7586394.html

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Dont’ know if they are aldehyde fixable, but the monomeric cyanine fluorophores from Molecular Probes survive dehydration and epoxy embedding.  they are generally membrane impermeant, but will pass through some cationic channels such as certain purinergic and mechanotransduction channels.  
Let us know what works.  

Regards,
Glen MacDonald
Digital Microscopy Center
Box 357923
University of Washington
Seattle, WA 98195-7923  USA
[phone]
[hidden email]

> On Feb 1, 2017, at 6:25 AM, Dave Johnston <[hidden email]> wrote:
>
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> To join, leave or search the confocal microscopy listserv, go to:
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> Can anyone recommend a non membrane permiable, fixable, nuclear counterstain, which neither fluoresces far red, nor requires hard UV excitation (so DAPI is out) which can then withstand wax embedding for histology? We have a user who wants to test a novel delivery system into which an aqueous phase dye can be incorporated, the test being that if the delivery system gets into a cell and is processed, the dye will be released and enter the nucleus to bind the DNA and stain the cell. The experiments will be in vivo, hence there is a need to fix and wax embed.
>
> I know that there are membrane impermeant, fixable cytosolic amine reactive dyes which would stain the cell if delivered this way but wondered about a nuclear stain.
>
> There seems relatively little literature on fixable DNA dyes or does one assume that aldehyde based fixation will cross-link any already incorporated dye.
>
> Thanks in advance,
>
> Dave Johnston,
> Biomedical Imaging Unit,
> Southampton.