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Reliable cytotoxicity experiments - (Sep/25/2005 )

Hi all!

Has anyone used Promega´s CellTiter 96® AQueous One Solution Cell Proliferation Assay? I have tried to measure the cytotoxicity of my protein and I get the same level of absorbance in both control and transduced cells approx. 0.25. However, when I treated the cells with drugs (just to test the functionality of the kit), the absorbance was under 0.1. So, the kit seems to work, however what I wanted to ask..is the level of my absorbance high enough? And how do you present your results in general? As percentages or absorbances?

Thanks!

-Joana-

In my view the level of absorbance in very low, i generally incubate plate untill i get an OD of >0.5, and regarding the presentation, percent cytotoxicity is a ideal choice

-vilas-

Hi,

An absorbance of 0.25 is on the low end for the assay - I usually aimed for an Abs. of about 1 when I used MTS/PMS. What is your cell density? And how long are you incubating with the MTS? I reccomend going right up to the maximum suggested (4 hrs I believe).

Some cells just don't work very well in the MTS assay - the key rxn relies upon a dehydrogenase to form the formazan (brown stuff). I know one of my cells just wasn't very goood upon carrying out this reaction.

Anyway, MTS is a pain in the ... uh, well it's annoying. Have you tried Cell-Titer Blue? Also from Promega. If you have a fluorescent plate reader it's a bit less goofy in the results.

Good luck!

-chemist_guy-