A two-in-one dual channel chemosensor for Fe3+ and Cu2+ with nanomolar detection mimicking the IMPLICATION logic gate

A novel and easy-to-synthesize colorimetric and fluorescent chemosensor 1 was developed for the highly selective and sensitive recognition of Fe3+ and Cu2+. Receptor 1 showed a detectable color change from yellow to colorless with a blue-shift in the absorption spectra with Cu2+, while Fe3+ induced a color change from yellow to orange and a red-shift in the absorption spectra. In the emission study of 1, Fe3+ showed significant fluorescence enhancement with a slight red-shift while a selective fluorescence quenching was observed with Cu2+ over a wide range of tested metal ions. With Cu2+/Fe3+ as the chemical inputs, the 'on-off' emission profile of receptor 1 was developed as an IMPLICATION type logic gate at the molecular level.