Highly selective fluorescent sensing for CN- in water: utilization of the supramolecular self-assembly.

A simple 4-amino-3-hydroxynaphthalene-1-sulfonic acid is demonstrated to fluorescently sense CN(-) in water based on the mechanism of supramolecular self-assembly. This work provides a novel approach for the selective recognition of CN(-) anions. The detection limit of the sensor towards CN(-) is 3.2 × 10(-7) M, and other anions, including F(-), Cl(-), Br(-), I(-), AcO(-), H2PO4(-), HSO4(-) and ClO4(-), had nearly no influence on the probing behavior. Notably, the test strips based on S4 were fabricated, which could act as convenient and efficient CN(-) test kits.