Coumarin-hydrazone based high selective fluorescence sensor for copper(II) detection in aqueous solution

A new coumarin-hydrazone based fluorescent sensor (L2) for Cu2 + sensing has been developed. The sensor features a rapid and a linear response to Cu2 + with a 6-fold turn-off signal. UV-vis titration results indicate a 1:1 stoichiometry of L2/Cu2 + complex with a Ka of 0.1 μM.