These kits contain a DyLight 690- or DyLight 747-conjugated in vivo polycaspase probe, which is a cell-permeable fluorescent detector of active caspases indicative of apoptosis. The probes are comprised of a polycaspase peptide sequence (VAD) and a fluoromethyl ketone (FMK) moiety, which facilitate irreversible binding of the probe to active caspases, and either DyLight 690 or DyLight 747 Dye for near-infrared detection with a range of in vivo instrumentation. These probes are valuable for in vivo drug determination studies, because changes in apoptosis from drug reactivity can be measured by fluorescence imaging in live animals. An increase in apoptosis produces a greater attachment of probes and, subsequently, an increase in fluorescence output. The in vivo technique is nondestructive, thus eliminating the need to remove cells and tissues from sacrificed animals prior to analysis (which induces further apoptosis). Additionally, apoptosis can be monitored in a single animal at multiple time points, reducing the number of animals required for a given study.
Nontoxic–not harmful to valuable research animals
Cell-permeable–readily diffuses through all cells as it circulates throughout the body
Selective for active caspases–eliminates high background and false-positive results common with other caspase detection methods