Exploring the gelation and AIE properties of a tripodal acylhydrazone-based probe: turn-on Zn(ii) sensing in HEPES buffer

Abstract

Two C₃-symmetric acylhydrazone-based AIE active probes, TRI-QUI and TRI-NAP, were synthesized with different peripheral substituents. The probe containing a quinoline moiety in the periphery displayed a selective turn-on response towards Zn²⁺ in HEPES buffer, with a calculated detection limit of 6.45 μM. The probe TRI-QUI was also identified as a supergelator as it formed a gel in DMSO–H₂O (2 : 3, v/v) with a minimum gelation concentration of 0.5 mg mL⁻¹. The gelator could interact with various metal ions or anions in the gel phase. Furthermore, the gelator could encapsulate small molecules like methyl orange and bromophenol blue, making the probe a multifunctional smart material.