Selective fluorescent detection toluene in water by a novel and simple tetra-hydrazone-biphenol-based chemosensor

Detection of toluene (Tol) at a very low level in aqueous solution is significant in the chemical and industrial process. Herein, we were rationally employing a “synergistic effect” in the design of Tol sensor and synthesized a novel supramolecular fluorescent sensor (FB) based on a tetra-hydrazone-biphenol derivative. Interestingly, the sensor FB can selectively and sensitively detect Tol by distinguishing fluorescent change, and the detection limits (LOD) is 8.19 × 10−6 M. This Tol sensing process was achieved through the synergistic effect based on the collaboration of the tetra hydrazine and the hydroxyl groups. In addition, the sensing mechanism between FB and Tol was further investigated by experiments and density-functional theory (DFT) calculations. This work provides a feasible way to detect Tol by synergistic effect, and this recognition behavior makes FB a potential probe to detect Tol in environmental systems.