I have used 50 uM to block capases. This concentration was successful to block apoptosis in the sub G1 analysis when it was oretreated one hour before my drug, however, I have detected also a cl. PARP1 band in western blot of the same sample.

I was planning to rise the amount of Z-VAD-FMK up to 100uM but I found that was not common in the literature.