The CaspACE™ Assay System, Colorimetric, provides reagents for measuring the activity of caspase-3. The system includes a colorimetric substrate and a cell-permeant inhibitor that allow quantitative measurement of caspase-3 (DEVDase) protease activity. The colorimetric substrate (Ac-DEVD-pNA) provided is labeled with the chromophore p-nitroaniline (pNA). pNA is released from the substrate upon cleavage by DEVDase. Free pNA produces a yellow color that is monitored by a spectrophotometer at 405nm. The amount of yellow color produced upon cleavage is proportional to the amount of DEVDase activity present in the sample.
The potent, irreversible and cell-permeant pan-caspase inhibitor Z-VAD-FMK is provided in the CaspACE™ Assay System, Colorimetric. The addition of the Z-VAD-FMK Inhibitor prior to the induction of apoptosis in cell culture inhibits the activation of the caspase cascade, including caspase-3.