CellEvent™ Caspase-3/7 Green Detection Reagent is a novel fluorogenic substrate for activated caspase-3/7 that is compatible with both live cell and fixed imaging, with absorption/emission maxima of ∼502/530 nm. Activation of caspase-3 is an essential event during apoptosis, making this an optimized reagent for analysis of apoptotic cells.
• Optimized caspase-3/7 substrate for apoptosis analysis
• Easy to use—add and read; no cell lysis required
• Use for time course measurements; easily select the time point of interest
• Compatible with both live cell fluorescence-imaging and formaldehyde-based fixation methods
• Multiplex enabled—combine with other fluorescent reagents to confirm apoptosis in the same cell or cell population
CellEvent Caspase-3/7 Green Detection Reagent is a four-amino acid peptide (DEVD) conjugated to a nucleic acid-binding dye with absorption/emission maxima of ∼502/530 nm. The DEVD peptide sequence is a cleavage site for caspase-3/7, and the conjugated dye is non-fluorescent until cleaved from the peptide and bound to DNA.
Principles of action
CellEvent Caspase-3/7 Green Detection Reagent is intrinsically non-fluorescent as the DEVD peptide inhibits the ability of the dye to bind to DNA. However, after activation of caspase-3/7 in apoptotic cells, the DEVD peptide is cleaved, enabling the dye to bind to DNA and produce a bright, fluorogenic response. The fluorescent emission of the dye when bound to DNA is ∼530 nm and can be observed using a standard FITC filter set.
Simple three-step protocol
To use CellEvent Caspase 3/7 Detection Reagent, simply add it to cells, incubate 30 minutes, and visualize (see figure). Apoptotic cells with activated caspase-3/7 will have bright green nuclei, while cells without activated caspase 3/7 will have minimal fluorescent signal (see figure).
Assay versatility allows for live cell detection and fixation
This robust assay enables the examination of caspase-3/7 activation in live cells. Furthermore, since wash steps are not necessary for detection, fragile apoptotic cells typically lost during wash steps are preserved. Importantly, the fluorescent signal from CellEvent Caspase 3/7 Detection Reagent can survive fixation and permeabilization. This allows for the flexibility to perform end-point assays and probe for other proteins of interest using immunocytochemistry.