A novel dual-response triphenylamine-based fluorescence sensor for special detection of hydrazine in water

A novel-fluorescent sensor named TPAPI, is designed and constructed successfully. In DMSO/H 2 O (pH = 7.4) system, the TPAPI sensor demonstrates two different fluorescent responsive properties with the water volume fraction ( f w ): At 90%, the TPAPI shows an aggregation induced emission (AIE) effect around 670 nm, and can be used as a turn-off sensor; Meanwhile, at 10%, based on the fluorescent property of titration product, the aggregation caused quenching (ACQ) type fluorescent sensor can be constructed around 470 nm with LOD at 1.37 × 10 −7 mol·L −1 . The TPAPI sensor exhibits outstanding selectivity, anti-interference for hydrazine among thirty molecules and ions. The sensing mechanism is attributed to the formation of hydrazone (TPAP-N 2 H 4 ), confirmed by LC-MS. Theoretical calculations further confirm TPAPI molecules possess AIE property and TPAP-N 2 H 4 has the ACQ character. In addition, the TPAPI test strip can be prepared and applied successfully for the detection of N 2 H 4 .