A novel fluorescent and colorimetric dual-channel sensor for the fast, reversible and simultaneous detection of Fe3+ and Cu2+ based on terthiophene derivative with high sensitivity and selectivity

A novel terthiophene-derived colorimetric and fluorescent dual-channel sensor termed TTA was designed and synthesized. The sensor TTA showed a significant fluorescence turn-on response to Fe3+ and obvious fluorescence turn-off response to Cu2+ with some good features including chromogenic reaction, high sensitivity and selectivity, ultrafast response time, high reversibility, wide pH working range along with low detection limits (1.09 x 10(-7) and 4.48 x 10(-7) M). The Fe3+/Cu2+-binding mode and recognition mechanism of the sensor were investigated by Job's plot, H-1 NMR titration, FTIR and HRMS spectra. Moreover, the sensor was employed to rapidly and visually determine Fe3+ and Cu2+ in water based on TTA-based paper test strips and solid silica gel with good results.