First electropolymerized carbidopa-based molecularly imprinted film: disposable electrochemical sensor for monitoring of anti-COVID-19 drug favipiravir in human plasma

Abstract

Real-world applications and point-of-care testing in real human samples render molecularly imprinted polymer (MIP)-based sensors particularly pertinent. The enormous progress in the field of MIPs has extended the exploration of new molecules as functional monomers for more effective recognition and binding with the target analyte. Herein, for the first time, carbidopa was utilized as a novel monomer in facile electropolymerization of molecularly imprinted film for monitoring of favipiravir (FAV) in biological fluids and pharmaceutical tablets. The disposable electrochemical sensor fabrication was based on an electropolymerized film of poly-carbidopa molecularly imprinted polymer coated on a pencil graphite electrode (PCD-MIP/PGE). Using cyclic voltammetry (CV), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM), the manufactured electrode was characterized. Under the optimum conditions, the proposed sensor showed good linearity over two concentration ranges 5.00 × 10-6 to 5.00 × 10-5 mol/L and 7.00 × 10-5 to 1.00 × 10-3 mol/L using differential pulse voltammetry (DPV). The lower limit of detection (LOD) was down to 1.67 µmol/L. Besides being disposable, cost-effective, and simple in manufacturing and handling, PCD-MIP/PGE is selective and stable. Therefore, PCD-MIP/PGE is considered an attractive analytical tool for point-of-care diagnostics and quality control of FAV.