Calcein, a fluorescein derivative, operates as a green fluorescent sensor for proteases in the presence of Cu(II). Activites of proteases, acylases and aminopeptidase are readily followed using this versatile sensor.

This work was carried out in the group of Prof. Jean-Louis Reymond.

References:

• K. E. S. Dean, G. Klein, O. Renaudet, J.-L. Reymond;
  "A green fluorescent chemosensor for amino acids provides a versatile high-throughput screening (HTS) assay for proteases"
  Bioorg. Med. Chem. Lett., 13, 1653-1656, (2003); doi:10.1016/S0960-894X(03)00280-4.
• J.-L. Reymond, G. Klein, H.-K. Nguyen;
  "Method for Detecting a Reaction by Measuring a pM Change"
  World Intellectual Property Organization, International Patent No. WO/2002/086150, 31.10.2002; http://patentscope.wipo.int/search/en/WO2002086150.