Sensitive Recognition of Acetamiprid with a Unique Electrochromic Molecular Imprinted Polymer Sensor

Abstract

The development of molecularly imprinted polymers (MIPs) and the applications for them have attracted a great deal of interest during the last two decades. MIPs are generally used in different fields, specially molecularly imprinted electrochemical sensors (MIECS), due to their particular design and specific detection abilities [1]. The advantages of an electrochemical MIP sensor include low cost, easy operation, rapid response time and excellent potential for miniaturization and construction for portable equipment applications [2]. In the scope of this work, we performed that electropolymerization of IrO2 as an electrochromic material on an indium tin oxide (ITO) glass substrate and electrosynthesis on this electrode using pyrrole as a functional monomer in the presence of acetamiprid as template were used to create the electrochromic molecular imprinted polymer sensor (MIP/IrO2/ITO). With the created electrochromic MIP sensor, it is intended to create a selective pesticide sensor by utilizing molecular imprinted polymer (MIP) technology, and to detect with the naked eye by color change depending on the acetamiprid concentration by using electrochromic material. The IrO2/ITO electrochromic film demonstrated magnificent cycle stability (100 cycles), high coloration efficiency (400 cm2 C-1 at 450 nm), and quick coloring/bleaching reaction time (8.60s/7.10s, respectively). By using in-situ spectroelectrochemical measurements, these optical properties of MIP/IrO2/ITO were obtained at various acetamiprid concentrations for quantitative analysis. By using differential pulse voltammetry between -0.2 V and +0.8 V (versus Ag/AgCl in 0.1 M PBS), the sensor performance of MIP/IrO2/ITO was assessed. In an acetamiprid concentration range of 4.29–38.6 nM, the MIP/IrO2/ITO electrode demonstrated linear response with a detection limit of 2.72 nM, sensitivity of 47.2 µA nM-1, and repeatability of 0.87%. Keywords: Electrochromism; Molecularly imprinted polymer (MIP); Pyrrole; IrO2;Acetamiprid; Electrochemical sensor; Spectroelectrochemistry. Acknowledgements This work was supported by The Scientific and Technological Research Council of Türkiye, TUBITAK (Project No:121Z784) as the financial.