I have been suspending my cells for flow cytometry in the regular medium I normally use sans FBS. I recently read that phenol red increases the background fluorescence for eGFP detection which is something I definitely don't want! I thought I could just go ahead and buy medium without phenol red in it but that also lacks glucose, glutamine-L and sodium pyruvate.
Are any of those needed for the cells to remain viable for about 90 minutes? How long are they okay in PBS? I just need them to not change in their spectral characteristics whilst they wait their turn on the flow cytometer. The fluorochromes in use are proteins expressed from genomic insertion and/or plasmids, fluorochrome-conjugated annexin V and a cell membrane-impermeant vitality stain (which I add 5-30 minutes prior to analysis).
If I go for one of the DMEMs, I think I might also add 1% FBS since I read that's tolerated by the cytometer and the cells remain viable for longer.
I've also been keeping my cells at room temperature and not on ice.
PBS (no calcium, no magnesium)
FluoroBrite™ DMEM for which the manufacturer suggests there is lower background than regular medium without phenol red - needs glutamine-L to be like my "normal" (I haven't done this long) cytometry medium.
DMEM, no glucose, no glutamine, no phenol red - needs glutamine-L, glucose and sodium pyruvate to be like my "normal" (I haven't done this long) cytometry medium.
Edited by seanspotatobusiness, 28 March 2014 - 02:59 PM.