MMP-10 (stromelysin 2) cleaves extracellular matrix proteins, but is unable to cleave the triple-helical fibrillar collagens. This enzyme is involved in several pathological conditions, such as cancer, arthritis and wound healing. SensoLyte® 520 MMP-10 Assay Kit uses a 5-FAM (fluorophore) and QXL®520 (quencher) labeled FRET peptide substrates for continuous measurement of the enzyme activities. In an intact FRET peptide, the fluorescence of 5-FAM is quenched by QXL® 520. Upon the cleavage of the FRET peptide by MMP-10, the fluorescence of 5-FAM is recovered, and can be continuously monitored at excitation/emission = 490 nm/520 nm. With superior fluorescence quantum yield and longer emission wavelength, 5-FAM/QXL®520 based FRET peptide is less interfered by the autofluorescence of test compounds and cellular components and provides better assay sensitivity. The assays are performed in a convenient 96-well or 384-well microplate format.