Novel acridine-based thiosemicarbazones as 'turn-on' chemosensors for selective recognition of fluoride anion: a spectroscopic and theoretical study.

ABSTRACT: New thiosemicarbazide-linked acridines 3a-c were prepared and investigated as chemosensors for the detection of biologically and environmentally important anions. The compounds 3a-c were found selective for fluoride (F-) with no affinity for other anions, i.e. -OAc, Br-, I-, HSO4-, SO42-, PO43-, ClO3-, ClO4-, CN- and SCN-. Further, upon the gradual addition of a fluoride anion (F-) source (tetrabutylammonium fluoride), a well-defined change in colour of the solution of probes 3a-c was observed. The anion-sensing process was studied in detail via UV-visible absorption, fluorescence and 1H-NMR experiments. Moreover, during the synthesis of acridine probes 3a-c nickel fluoride (NiF2), a rarely explored transition metal fluoride salt, was used as the catalyst. Theoretical studies via density functional theory were also carried out to further investigate the sensing and anion (F-) selectivity pattern of these probes.

SUBMITTER: Isaac IO 

PROVIDER: S-EPMC6083729 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature