Graphene Nanoribbons/Manganese Oxide Nanocomposite Modified Electrode for Detection of Antimicrobial Drug Nitrofurantoin

Abstract

The design and development of a new kind of cost-effective electrode material with excellent selectivity and stability are still a great challenge in the field of electrochemical sensors. Recently, researchers have paid more attention to the electrochemical reduction of nitro compounds due to their hazardous nature. Nitro compounds play a vital role in various industrial applications. However, the direct discharge of nitro compounds to the environment as industrial wastewater is harmful. In this study, a nanocomposite made of 1D graphene nanoribbons decorated with manganese dioxide (GNR-MnO2) was prepared to fabricate an electrochemical transducer for the determination of nitrofurantoin (NFT) in biofluids. First, 1D GNR was prepared by unzipping of multiwalled carbon nanotubes. Second, the GNR was decorated with MnO2 by the hydrothermal reduction method. As-prepared GNR-MnO2 nanocomposite was comprehensively characterized by field emission scanning electron microscopy with EDX, XRD, UV-visible, electrochemical impedance spectroscopy, and cyclic voltammetry. Moreover, GNR-MnO2-coated glassy carbon electrode (GCE) exhibited good electrocatalytic activity toward NFT. The electroreduction of NFT was found at -0.40 V which was 50 mV lower than bare GCE. GNR-MnO2 nanocomposite modified GCE showed a well-defined linear reduction peak current for NFT from 10 nM to 1,000 μM. The selectivity of the sensor was also analyzed in the presence of other nitro compounds which confirmed that NFT can be selectively detected at -0.4 V. The GNR-MnO2 modified electrode was also able to separate reduction peaks of other nitro compounds. In addition, the detection of NFT was carried out in human urine samples with a good recovery of 99.60%-98.60%.