Novel salicylaldehyde derivatives as fluorescence turn-on sensors for cyanide ion

- New fluorescent compounds used as a CN− fluorescence “turn on” sensor were synthesized.
- The compound with 1 salicylaldehyde and 2 fluorogenic units gave the highest “turn-on” signal.
- In the presence of Triton-X 100, the detection limit of CN− was 1.6 μM in water.
- A paper-based sensor was developed for naked eye detection of 5 nmol CN.