Colorimetric and ratiometric fluorescent chemosensor for fluoride ion based on perylene diimide derivatives

Based on a perylene diimide derivatives(PDIs) platform, AM-PDIs was rationally designed and synthesized as a new colorimetric and ratiometric fluorescent sensor for naked-eye detection of fluoride ion with high selectivity over other halide ions. Addition of fluoride ion to a dichloromethane(DCM) solution of AM-PDIs resulted in an obvious color change (from red to blackish green) because of a large red shift (151 nm) in absorption. The recognition mechanism was attributed to the intermolecular proton transfer between a hydrogen atom on the amide N position of sensor and the fluoride anion. The detection limit was calculated to be 0.14 μM.

► It was the first time to report ratiometric chemsensor for F anion based on PDIs.
► This sensor showed a large red shift(151 nm) in absorption.
► The sensor had a low detection limit(0.14 μM).