| abstract |
Embodiments of the invention provide cathepsin K osteosorbent fluorogenic substrates (or other proteases). Using a bisphosphonate targeting moiety, the fluorogenic substrates provide at least one effective bone-targeted protease sensor. In some embodiments, the "probes" include a cleavable fluorophore-quencher pair bound by a peptide substrate of cathepsin K (or other protease) and attached to a bisphosphonate. Unlike existing probes that are removed in a few days in vivo, the probes described here (eg OFS-1) can monitor resorption for longer periods with a single dose. |