A new ionophore for chemical sensing of F−, CN− and Co2+ using voltammetric, colorimetric and spectrofluorimetric techniques†
The TPEI molecule with ether-imine functional groups was synthesized and characterized by spectroscopic techniques. The TPEI receptor was analyzed for its interaction with different cations and anions. TPEI showed instant visual color change on addition of fluoride, cyanide and cobalt ions, which led to a study of the interaction of TPEI with Co2+, F− and CN−. An obvious color change of TPEI from light yellow to colorless was observed for CN− through a nucleophilic addition mechanism, while F− was detected through a H-bonding mechanism with a distinct color change from light yellow to dark yellow. Co2+ was detected by pseudocavity formation of TPEI in the vicinity of cobalt ions causing a color change from yellow to blue. Paper strips of the TPEI receptor were also prepared, which can be used to detect the presence of Co2+, F− and CN−.