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New thiophene (TSC-1) and bipyridine (TSC-2) anchored thiosemicarbazones were synthesized for the recognition of biologically active and toxic analyte. Both the receptors TSC-1 and TSC-2 commonly exhibited strong sensitivity toward anions such as F–, AcO–, and CN– ions over other anions, whereas TSC-1 and TSC-2 recognized Cd2+ and Hg2+ ions, respectively. Both anion and cation recognition were clearly differentiated from colorimetric, absorption, and emission responses. A significant shift with remarkable fluorescence enhancement at 540 nm was observed for TSC-1-Cd2+, which describes an internal charge transfer (ICT) mechanism. In contrast, anion complexes of TSC-1 show fluorescence enhancement at 570 nm. TSC-2 acts as a photoinduced electron transfer (PET) sensor during both anion and cation sensing accompanied by fluorescence quenching. Furthermore, TSC-1/2 preferentially recognizes cations in the presence of competitive anions. Interestingly, selective detection of the CN– ion using the Hg2+-TSC-2 ensemble also achieved through a relay recognition method. Job’s plot analysis reveals that TSC-1/2 binds with the selective anions in 2:1 mode, and 1:1 mode was determined for Cd2+-TSC-1 and Hg2+-TSC-2, respectively. TSC-1 can be utilized for practical applications such as the recognition of targeted F– ions in daily used household toothpaste, and Cd2+ ion detection was achieved in living cells using bioimaging.

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