The Caspase-2 Colorimetric Assay Kit (Cat. No. L00294) provides a simple and convenient means of assaying the activity of caspase-2. Activation of ICE-family proteases and caspases initiates apoptosis in mammalian cells. The assay for caspase-2 is based on spectrophotometric detection of the chromophore pnitroanilide (pNA) after cleavage from the labeled substrate VDVAD-pNA. The pNA light emission can be quantified using a spectrophotometer or a microtiter plate reader at 400 or 405 nm. By comparing the absorbance of pNA from an apoptotic sample to an uninduced control, the relative increase of caspase-2 activity can be determined.