A highly selective PET-based chemosensor for instant detecting of Zn2+

A simple Zn2+-selective chemosensor system based on acylhydrazone was designed and synthesized, which could detect Zn2+ ions in aqueous solution with high selectivity and sensitivity over a wide pH range by the mechanism of photo-induced electron transfer (PET). The obvious color changes and pronounced OFF-ON-type fluorescent signaling behavior can be seen by the naked eye. The detection limit of L2 for Zn2+ ion was as low as 0.13 mu M. In addition, L2-Zn2+ complex can be used as an ON-OFF chemosensor candidate for Cu2+, as the Zn2+-induced emission can be quenched upon addition of Cu2+. Moreover, test strips for Zn2+ based on L2 were also fabricated, which could be used as a convenient and efficient test kit for instantly detecting Zn2+ in aqueous solution.