Pillar[5]arene-based fluorescent polymer for selective detection and removal of mercury ions

Abstract

A novel pillar[5]arene-based thioacetohydrazone functionalized fluorescent polymer was designed and synthesized. This polymer not only contains pillar[5]arene units as the fluorophore (signal transducer) but also embedded the thioacetohydrazone group as the ionophore (cation receptor). Therefore, it displays specificity response for mercury ion over other common cations (Mg²⁺, Ca²⁺, Zn²⁺, Co²⁺, Fe³⁺, Pb²⁺, Cd²⁺, Ni²⁺, Tb³⁺, Cu²⁺, Eu³⁺, Fe²⁺, Cr³⁺, Ag⁺ and La³⁺) in DMSO/H₂O (1 : 1, v/v). Competitive cations did not show any significant changes in emission intensity and the fluorescence spectra detection limit was 8.12 × 10⁻⁷ M, indicating the high selectivity and sensitivity of the polymer towards Hg²⁺. Meanwhile, this polymer can efficiently remove Hg²⁺ from water.