Tunable poly(o-anisidine)/carbon nanotubes nanocomposites as an electrochemical sensor for the detection of an anthelmintic drug mebendazole

Abstract

The present work addresses the electrochemical detection of an anthelmintic drug mebendazole (MBZ) using glassy carbon electrode (GCE) modified with the hybrid nanocomposites of poly(o-anisidine) (POA) and multi-walled carbon nanotubes (CNTs). The POA/CNTs (PC) nanocomposites were synthesized with different concentrations of o-anisidine via chemical oxidative polymerization route. The formation of nanocomposites were characterized by field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy studies. The morphological analysis revealed a matrix transition on varying the o-anisidine concentration in the composites. The appropriate selection of polymer and the composite enabled the design of nanostructures with highly tunable charge transport properties. FTIR and Raman studies proposed the existence of interfacial interaction between POA and CNTs which enhanced the sensing efficiency. The electrochemical performance of MBZ on the modified electrode has been examined using cyclic voltammetry, differential pulse voltammetry and chronoamperometry techniques. The best composite ratio for effective determination of MBZ, the oxidation–reduction properties and the electrochemical parameters governing the performance of the modified electrodes were studied by electrochemical approaches. Under the optimized conditions, the oxidation peak current presented a linear relationship with the MBZ concentration in the range from 1.0 to 35.0 µM with a detection limit of 0.4 μM (S/N = 3) by DPV method. The modified electrode was also used for the determination of MBZ in pharmaceutical samples. With the advantages of simplicity and high sensitivity, the fabricated sensor would provide a promising platform for the detection of other such anthelmintic drugs.