The Guava Caspase Assay Suite of fluorescent-based assays for Caspase 3/7, 8, 9 and multi-caspase employ the same protocol making it easier to perform multiple caspase assays in parallel. Further, Guava caspase reagents are membrane permeable allowing one to measure intracellular levels of the enzyme without using harsh lysis methods. The Guava Caspase Assays employ a FLICA (Fluorescent Labeled Inhibitor of Caspase) reagent that specifically identifies active caspases. Each FLICA is comprised of three subunits:
– an active site binding peptide to confer specifi city (DEVD for caspase 3/7, LETD for caspase 8, LEHD for caspase 9, and VAD for multi-caspase)
– a covalent crosslinking agent (FMK)
– a green (FAM) or orange-red fl uorescent probe (SR): SR is excited by blue or green lasers (PCA Systems or EasyCyte Systems), FAM by blue lasers only (EasyCyte Systems)
The Guava Caspase Assays also include the nuclear DNA stain, 7-AAD, to simultaneously evaluate membrane integrity and cell viability.