Controllable and reversible sensing cyanide ion using dual-functional Cu (II)-based ensemble

摘要

In this work, a dual-functional Cu2+-based ensemble (2S.Cu2+) was well designed and characterized. Then, the successional and discriminating sensing for CN- over other competitive species (H2PO4- and biothiols) was achieved based on the disaggregation of 2S.Cu2+ ensemble and the deprotonation of imidazole NH of regenerated sensor S in aqueous solution, respectively. The visual sensing mechanism could be clearly demonstrated by H-1 NMR, HRMS and energy changes between the HOMO-LUMO band gaps. Furthermore, the reversibility and reusability of S and 2S.Cu2+ upon alternating addition of CN-/H+ and CN-/Cu2+ were studied. Interestingly, the sequential sensing for biothiols (cysteine, glutathione and homocysteine) and CN- was also realized through spectroscopic methodology and test paper strips. This work may provide a feasible strategy to discriminate CN- over H2PO4- and biothiols with high selectivity and sensitivity through Cu2+-based ensembles. (C) 2021 Elsevier B.V. All rights reserved.