A simple highly sensitive and selective turn-on fluorescent chemosensor for the recognition of Pb2+

Abstract A simple highly sensitive and selective turn-on fluorescent chemosensor L based on bis-Schiff-base for Pb 2+ ions was synthesized and characterized by spectroscopic techniques. L having high binding affinity towards Pb 2+ ions of 2.10 × 10 4  M −1 selectively detects Pb 2+ ions with almost no interference among various competitive ions by a 11-fold fluorescent enhancement in CH 3 CN/H 2 O (95:5, v/v) solution over a wide pH range. Moreover, sensor L displayed a lower detection limit of 3.80 × 10 −7  M, which is low enough for sensing sub-millimolar concentration of Pb 2+ encountered practically.