A new dibenzothiophene-based dual-channel chemosensor for cyanide with aggregation induced emission

Abstract

A new dibenzothiophene-based barbituric acid derivative (DTB) with an aggregation induced emission (AIE) effect was synthesized as a naked-eye colorimetric and fluorescent probe for CN⁻. The UV-vis spectra and fluorescence spectra of DTB in a DMSO/H₂O mixture changed with different water fractions (f_w). Nano-aggregates of DTB were formed with the strongest fluorescence emission when f_w reached 99%. Furthermore, DTB expressed good selectivity and high sensitivity for CN⁻ in 99% aqueous DMSO solution. The sensing mechanism of DTB for CN⁻ was confirmed by ¹H NMR titration, HRMS spectra, Job's plot and DFT calculations. Furthermore, DTB detected CN⁻ with a low detection limit (21.6 nM), wide pH range (4–10), high anti-interference ability and fast response time (10 s). Moreover, DTB-based test strips were prepared for CN⁻ detection, and DTB could detect CN⁻ in real water samples.