Cell Meter(TM) Live Cell Caspase 3/7 Imaging Kit *Green Fluorescence*

Cell Meter(TM) Live Cell No Wash Caspase 3/7 Imaging Kit uses our recently developed cell-permeable fluorogenic caspase substrate, ApoSight(TM) Green Caspase 3/7, the first fluorogenic probe, for the direct detection of caspase activities in live cells. ApoSight(TM) Green Caspase 3/7 substrate consists of three moieties including a). a masked fluorophore, b). a caspase-selective peptide fragment (DEVD), and c). a cell-penetrating moiety. The cell-penetrating moiety carries the probe into live cells. Upon entering live cells, the caspase-selective peptide fragment is cleaved by a caspase to release the masked fluorophore. The intensity of recovered fluorescence is directly related to the activity of caspase to be measured. Compared to the existing caspase assays in live cells, ApoSight(TM) Green Caspase 3/7 substrate is much more robust, convenient, and accurate. ApoSight(TM) Green Caspase 3/7 substrate releases a fluorophore that has Ex/Em ~490/520 nm. It does not need a DNA interaction to be fluorescent as reported for NucView reagents. It does not inhibit caspase activity as reported for the FMK peptide probes. Although fluorescent FMK peptide inhibitors of caspases are widely used for detecting caspase activities in live cells, this technology has a few severe limitations: a). FMK caspase inhibitors have high cytotoxicity since FMK peptides bind covalently to active caspases, b). The irreversible covalent binding of FMK peptides to caspases inhibits caspase activities, causing false positive apoptosis, c). FMK assays have extremely high background, and require intensive washings, resulting in extremely low throughput, d). FMK peptides are not stable in aqueous solutions and must be used immediately. Cell Meter(TM) Live Cell No Wash Caspase 3/7 Imaging Kit provides an optimized fluorescence imaging assay for monitoring caspase3/7 activity. The assay can be performed in a convenient 96-well or 384-well microtiter-plate format and easily adapted to automation.