Advanced Pathways for the Preparation of Sensitive Lead(II) Ion Sensor: Ion-Imprinted versus Acid-Assisted...

In this study, a sensing polymer film was obtained from the polymerization of two monomers3-thiopheneacetic acid and 1-vinylimidazole. The polymerization process occurred through two distinct methods: acid-assisted polymerization and the ion-imprinting technique, with simultaneous deposition of the sensing film onto carbon rods. The deposition method plays a significant role in the films' responses to Pb²⁺ ions. We detected Pb²⁺ ions in the absence and presence of interfering ions using square-wave voltammetry (SWV) and potentiometric detection. The sensing film obtained by acid-assisted polymerization (AS-P) demonstrated superior performance in comparison to the sensing film obtained by the ion-imprinting (II-P) technique. Specifically, films obtained by the AS-P process and measured using SWV techniques could detect Pb²⁺ ions in the presence of low (400 μM) and high (0.001 M) concentrations of interfering ions (Cu²⁺, Zn²⁺, and Co²⁺). Additionally, AS-P films can be used for the potentiometric detection of Pb²⁺ ions within a linear concentration range of 10 μM to 158 μM.