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Non-fluorescent live/dead stains for prokaryotes - (Sep/18/2012 )

I will be researching in Antarctica at the end of the year and as such, I wont have an epifluroescence (only a compound) microscope available.
I need to conduct viability counts of prokaryotic bacteria, most likely using a haemocyctometer, and am looking for a stain which could be used for this purpose. I've looked into Trypan blue but have a few specific questions about it.
1) Can it be taken up by prokayotic cells?
2) Is there a counter stain available which I can use to for counting my live bacteria?
Any help in regards to trypan blue or alternative stains would be greatly appreciated.


This is a very good question. I am not sure how Trypan Blue would work on gram-positive bacteria. In order to differentiate living cells from dead ones we normally just grow them in broth and check OD. But that would need an incubator and a spectrophotometer, which you might not have in Antarctica. I searched the web just now, there are some commercial kits, but most of them use propidium iodide and that needs fluorescence microscope. Then I searched PubMed but couldn't find anything useful either. So I also want to know the answer. If anybody knows please let us know.


We will have an incubator and spectrophotometer down there. I've planned on measuring optical density to get some growth curves. How does OD differentiate between live and dead cells though?
I saw a few of those kits, like the live/dead BacLight and they looked pretty cool but as you said, all I could find were fluorescence stains.