A Novel AIE-active Salicylaldehyde-Schiff Base Probe with Carbazole group for Al 3+ Detection in Aqueous Solution

Abstract

A donor-acceptor Schiff-base fluorescent probe BKS with chelation enhanced fluorescence (CHEF) mechanism was designed and synthesized via benzophenone(Acceptor), salicylaldehyde and carbazole(Donor) for Al 3+ detection, which exhibited typical aggregation-induced emission (AIE) characteristic. BKS probe could provide outstanding selectivity to Al 3+ with a prominent fluorescence “turn-on” at 545nm in a wide pH range of 2-11. Which was significantly lower than the standard of WHO [1-2] guidelines for drinking water. By the Job’s plot, the binding stoichiometry ratio of probe BKS to Al 3+ was determined 1:1. The proposed strategy offered a very low limit of detection at 1.486μM in THF/H20(V/V=1:4 HEPBS=10mM, pH=7.40) and a wider linear range of 0-500μM. Furthermore, the probe could hardly be interfered by other examined metal ions. The analysis of Al 3+ in real water samples with propriate recovery (100.72~102.85) with a relative standard deviation less than 2.82% indicated the accuracy and precision of BKS probe and the great potential in the environmental monitoring of Al 3+ .