Cathepsins are a class of globular lysosomal proteases playing a vital role in mammalian cellular turnover. They degrade polypeptides and are distinguished by their substrate specificities. Cathepsin K is the lysosomal cysteine protease involved in bone remodeling and resorption. It has potential as a drug target in autoimmune diseases and osteoporosis. The SensoLyte® Rh110 Cathepsin K Assay Kit provides a convenient assay for high throughput screening of enzyme inhibitors or for continuous assay of enzyme activity utilizing a fluorogenic peptide. Upon enzyme cleavage, the peptide releases the Rh110 fluorophore with bright green fluorescence that can be detected at Ex/Em=496/520 nm. The kit contains: • Rh110 based fluorogenic substrate (Ex/Em=490/520 nm upon cleavage) • Assay buffer • Procathepsin K • Activation buffer • Inhibitor • Fluorescence reference standard for calibration • A detailed protocol Kit size: 100 assays (96-well plate)