Azine Based Oligoesteric Chemosensors for Cu Ion Detection: Synthesis, Structural Characterization, and Theoretical Investigations.

Synthesized monomer and its three oligoesters were characterized by techniques such as H, C{H}, IR, UV, GPC and applied to chemosensor applications. A series of metal ions was studied with fluorophores to evaluate the sensitivity towards Cu ion. The fluorophores results exhibit the selective and sensitive "Turn off" fluorescence response with Cu ion in DMF/HO (1:1, pH: 7.4, fluorophore: 5 µM) solution. Binding stoichiometry and binding constant of fluorophores were calculated using Stern-Volmer equation and Benesi-Hildebrand plots, respectively. Structure of fluorophores were studied using DFT, B3LYP/6-311 +  + G(d,p) level basis set. Quenching mechanisms and electrical properties of fluorophores were explained with theoretical outcomes. Iodine doped and undoped oligoesters electrical conductivity were studied in solid-state and the conductivity was gradually increased with increase the contact time of iodine with oligoesters. At different frequencies and temperatures, the dielectric measurement was calculated using the two-probe method. Among all oligoesters, DMDAP exhibited high electrical conductivity and DMDMP has a higher dielectric constant value than other oligoesters.