| abstract |
The present invention provides active-based probe compounds for use in the labeling of cysteine proteases. The compound is targeted to the protease through a specific targeting element. The compound further comprises a detectable element, for example, a fluorescent label, a radioactive label, or a chelator. In some cases, the compound further comprises a clearing element that is released in the reaction with the protease. Also provided are compositions comprising compounds and methods of using the compounds to label proteases in animals and to visualize tumors in animals, for example. |