High toxicity and different applications of cyanide and fluoride ions in the chemical, biological, and medical fields encouraged attention for design and fabrication of new probes for their detection. Herein, a novel phenylthiosemicarbazide-based chemosensor (PTSCS) was synthesized by condensation reaction and applied for colorimetric detection of F− and CN− ions. Techniques including naked-eye test, paper test strips, UV–visible and 1H NMR spectroscopic techniques were used to confirm the interaction of PTSCS with F− and CN− ions. Addition of cyanide or fluoride ions to the solution of PTSCS results in color change from yellow to dark red with a large bathochromic shift (~ 174 nm) in absorption spectra. Probe PTSCS showed linear responses toward F− and CN− ions with detection limits (LOD) of 0.044 μM and 0.075 μM, respectively. It is interesting that no other tested ions caused any color change when these ions are added to the PTSCS solution. The interaction binding mode of PTSCS with F− and CN− was found to be 1:1 based on the Job’s plot analysis. Furthermore, the developed chemosensor was applied for the qualitative and quantitative analysis of F− and CN− in toothpaste, apple seeds oil and water samples. Test strips based on PTSCS were fabricated using the filter papers for possible commercialization.
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Keywords: Chemosensor; 4-Phenylthiosemicarbazide; Fluoride ion; Cyanide ion; Test strips