Our DQ gelatin is a fluorogenic substrate that can be used to detect protease activity in vitro with high sensitivity. This substrate, formerly available only in our popular EnzChek Gelatinase/Collagenase Assay Kit (E-12055), consists of highly quenched, fluorescein-labeled gelatin. Upon proteolytic digestion, its bright, green fluorescence is revealed and can be used to measure enzymatic activity. The fluorescence increase can be monitored with a fluorescence microplate reader or fluorometer.