Does the alamar blue dye need to be added to the cells after particular time periods independently to determine cell viability or can it be added once and then checked over a certain amount of time (say 2 days)? The problem is that I'm not sure when my drug is supposed to actually affect the proliferation of my cells so I'm hoping to add the alamar blue as soon as I add the drug and then just check its fluorescence over time. I'm assuming that once the drug takes effect, the proliferation of the cells treated with the drug drops (the drug is supposed to be a growth inhibitor) so that in comparison to the control cells with no drug, I get a lower fluorescence. The issue is that just ran this experiment and it's been 24 hours but my fluorescence for both the treated and untreated cells have been the same. I'm hoping, though, that in another 24 hours, once the drug goes into effect (assuming it takes 48 hours to take into effect), I'll have higher flourescence levels in the control cells and lower levels in the treated cells. Will/Should this be the case?
Also, a lot of studies add the alamar blue at particular time points. For example, they'll treat with a drug, wait 24 hours, then add alamar blue and read flourescence only after 4 hours (and no time after). My question is--- is there anything wrong with adding the alamar blue at the same time as the drug? Shouldn't you get higher flourescence in the controls at some point regardless of when you add the drug (assuming the drug has anti-proliferative effects). Also, if I do decide to wait 24 hrs, then add the alamar blue, how long does it take for the alamar blue to actually reflect the number of viable cells that I have? Some studies check after one hour, others after 4. Any help would be greatly appreciate it!
Thanks so much~
Edited by Yass1211, 03 November 2011 - 08:01 PM.