Cathepsin B-sensitive nanoprobe for in vivo tumor diagnosis

We developed a cathepsin B-sensitive nanoprobe (CB-NP) with a cathepsin B substrate peptide probe and tumor-targeting glycol chitosan nanoparticles. The CB-NP could accumulate in tumor tissues, enter into tumor cells, and generate fluorescent signals in cytosol in response to cathepsin B. The results of non-invasive fluorescence imaging in a tumor-bearing mouse model demonstrated the potential of CB-NP for tumor diagnosis in clinical fields.