A new naphthopyran-based chemodosimeter with aggregation-induced emission: Selective dual-channel detection of cyanide ion in aqueous medium and test strips

Abstract

A novel green emissive AIE active probe, a naphthopyran-malononitrile conjugate (NPM), was utilized for selective dual channel (colorimetric and fluorimetric) sensing of CN− ions in DMSO-water (2/3, v/v, pH = 7.4) solution. The nucleophilic addition of CN− ion on the dicyano-vinyl group breaks the π-electron conjugation, thereby restricting intra-molecular charge transfer(ICT) process in the probe NPM and leading to a visual color change and observable spectral changes. NPM shows good selectivity for CN− ions with the LOD of 4.27 × 10−7 M, which renders it a candidate probe for cyanide detection in aqueous environments. For the practical applicability, NPM-coated paper strips were prepared for convenient, on-site detection of cyanide in aqueous medium.