In article <32D14DE4.6D81 at umich.edu>, pboucher at UMICH.EDU says...
>>I am interested in counting colonies that stably express GFP for
>cytotoxicity assessment studies. I want to be able to count colonies
>that lack and express GFP. Is there an easier way of doing this than
>counting the colonies under a fluorescent microscope? Perhaps some sort
>of fluorescent dish scanner. I would appreciate any input. Thank-you.
> Laura Zerbe Rubsam
Could you get away with lysing the plate of cells and then comparing
the fluorescence (in a fluorimeter) with protein or DNA concentration?
You could then relate this to the results of GFP-negative and GFP-fully-
expressing cells (measured in separate determinations).
This is clearly the quick'n'cheap way of doing it. For more
precise results you could use a FACS if you have one available.
Has anyone tried modifying a Coulter Counter...?
Bernard
Bernard Murray, Ph.D.
bernard at elsie.nci.nih.gov (National Cancer Institute, NIH, Bethesda MD, USA)