Matrix metalloproteinases (MMPs) belong to a family of secreted or membrane-associated proteins capable of digesting extracellular matrix components. The importance of MMPs in tumor development and invasion as well as other diseases is well known. The SensoLyte® 570 Generic MMP Assay Kit is optimized to detect the activity of a variety of MMPs, including MMP-1, 2, 7, 8, 9, 10, 13, and 14. This kit is ideal for detecting generic MMP activity in biological samples or for high throughput screening of MMP inducers and inhibitors using purified MMPs. This kit uses a 5-TAMRA (fluorophore) and QXL® 570 (quencher) labeled FRET peptide substrate for continuous measurement of the enzyme activities. In an intact FRET peptide, the fluorescence of 5-TAMRA is quenched by QXL® 570. Upon the cleavage of the FRET peptide by MMPs, the fluorescence of 5-TAMRA is recovered, and can be continuously monitored at excitation/emission = 540 nm/575 nm. 5-TAMRA/QXL® 570 based FRET peptide is an ideal substrate for screening MMPs inhibitors since it is less interfered by the autofluorescence of test compounds due to longer emission wavelength. The assays are performed in a convenient 96-well format.