Molecularly imprinted polymer based sensor for measuring of zileuton: Evaluation as a modifier for carbon paste electrode in electrochemically recognition

Abstract

For the first time, a modified carbon paste electrode by using molecularly imprinted polymer (MIP) was designed and prepared as a high performance selective sensor for Zileuton determination. The MIP was synthetized by noncovalent mechanism via bulk polymerization in presence of Zileuton as template molecule. The Polymer backbone was based on methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA). The Polymers was chemically characterized by Fourier Transform Infrared spectroscopy (FT-IR) analysis. Morphology of MIP particles was studied by Scanning Electron Microscopy (SEM) technique. Then the MIP and non-imprinted polymer (NIP) as blank one were used to modify bare carbon paste electrode. The modified electrodes were evaluated to study electrochemical behavior of Zileuton by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. Some factors such as pH of electrolyte and scan rate were optimized for current response of modified carbon paste electrode. Electrochemical response for Zileuton on the bare carbon paste electrode and modified electrodes were compared together. The designed methodology resulted the wide concentration linear range with the correlation coefficient of R2 ≥ 0.9920, limit of detection (LOD) = 0.189 μg mL−1 and RSD ≤ 2.65, suitable molecular recognition and high selectivity for Zileuton compared to the studied structurally similar compounds. The modified sensor, also presented high ability for Zileuton determination in spiked human plasma (11.8 μg mL-1) with recovery of 99.96%.