Flavonol-based fluorescent indicator for determination of β-glucosidase activity

A novel fluorescent probe, based on the excited-state intramolecular proton transfer (ESIPT) phenomenon, for evaluation of β-glucosidase activity was designed. The synthesis of the probe was optimized. The conditions for the monitoring of enzymatic cleavage of the probe were developed and discussed from the point of view of reaction kinetics and simplicity of the method.