GFP tagged protein expression detection - (Dec/16/2011 )

I want to know whether it is possible to differentiate cell containing one GFP linked protein expressing plasmid from two GFP linked protein expressing plasmid just by FACS.
Thanx.

You mean if you have twice the signal intensity? Which is usually not the case, but that's a different story... I think it is rather difficult to do so. Usually you have a broad signal intensity peak, spanning half a log, due to differences in promoter activity between cells or copy number of plasmids taken up. A twofold increase would be masked by this. To differentiate two populations clearly, you'd need a 10fold difference in signal strength. There are ways however to get a more narrow peak.
I think if you have time, go ahead and try it out. And let us know how it worked.