Tailoring an HSO 4 - anion hybrid receptor based on a phenazine derivative.

A catechol-functionalized phenazine imidazole (PD) was tailored with 2,3-diaminophenazine and 3,4-dihydroxy benzaldehyde, and it served as a hybrid acceptor for capturing HSO ₄ ^- anions. The selectivity and sensitivity of the PD receptor for anion sensing were studied. It was found that the PD receptor could not only display a preferable sensitivity to HSO ₄ ^- ions with a "turn-off" fluorescence response, but also have a strong anti-interference ability toward other common anions, especially basic anions such as CH ₃ COO ^- , HPO ₄ ^2- , and H ₂ PO ₄ ^- . The anion recognition mechanism of PD towards HSO ₄ ^- is based on multiple hydrogen bond interactions. Finally, the strips for anion detection were prepared, which were verified to be a convenient and high-efficiency test kit for detecting HSO ₄ ^- ions with the naked eye.