Enzyme Assays

The PDQ Protease Assay™ is a colorimetric assay used to detect protease activity.  The proprietary substrate is susceptible to a wide range of proteases including serine, metallo, aspartate and cysteine proteases such as collagenase, proteinase K, papain, pepsin, bromelin, ficin, trypsin and chymotrypsin.  This substrate is a cross-linked matrix containing protein substrate and a dye-protein conjugate.  The matrix is supplied in plastic vials or 96-well microplates, ready-to-use.  Test samples containing putative protease activity are aliquoted into the vials which are then incubated at 37ºC.  Protease activity is detected spectrophotometrically with increasing optical density proportional to increasing enzyme activity.  Each kit is supplied with a trypsin control (BAEE equivalent units) for generating standard curves.

The PDQ Fluorescent Protease Assay™ employs the same matrix as the colorimetric protease assay except FITC is incorporated into the substrate as the tracer for enzymatic digestion of the substrate.  The fluorescent-based assays have the same broad spectrum susceptibility to proteases, but provide a more sensitive assay for detection of sub-nanogram amounts of protease.