Synthesis of oxygen vacancies rich CeO2-xNx/GCN hybrid nanostructure with great active interfaces for electrochemical detection of antiviral levofloxacin in pharmaceutical samples

Abstract

COVID-19 is an emerging viral infectious disease. Severe respiratory problems are considered an important syndrome of COVID-19 in humans. Levofloxacin (LEV), a promising fluoroquinolone antibacterial agent/therapeutic agent for influenza virus (H1N1)-induced pneumonia drug. These have been used as a potent antidote for acute respiratory tract infections. Owing to its excellent pharmacokinetic properties such as potential antiviral and scavenging activity, LEV has been used in controlling and treating COVID-19 during infectious emergencies. Even taking over the dosage of LEV and disposing of the embryonic toxic nature of LEV residues in the pharmaceutical research industry can cause adverse effects on the public health and environment. For this purpose, the development of great analytical tools is important to the detection of antiviral LEV for human health safety and environmental protection. In this work, we report a nitrogen (N) doped strategy to construct the enriched oxygen vacancies (OVs) on CeO2-xNx/GCN-2 hybrid nanostructure as an efficient electrocatalyst for the ultrasensitive detection of antiviral LEV. The effect of the N doping into the CeO2 (CeO2-xNx) lattice with increasing the large amount of OVs and boosted their redox properties (Ce4+→Ce3+), thus provided that a great electrochemically active site. Although the abundant OVs were conformed on the CeO2-xNx/GCN-2 from the peak-area ratio of Ce3+/Ce4+ and O2/O1 by X-ray photoelectron spectroscopy (XPS) assay. Owing to the strong electronic coupling between the OV-rich CeO2-xNx and the conductive GCN surface, thus CeO2-xNx/GCN-2 heterojunction achieved superior analytical performance for LEV oxidation with a good linear range from 0.01 μM to 710 μM, and detection limits of 5.6 nM (S/N = 3), and sensitivity 24.711μA μM−1 cm−2 at a very low working potential (0.7 V). The proposed hybrid sensor also exploited to the analysis of the pharmaceutical industry wastewater, pharmaceutical tablet and human urine samples with a satisfactory recovery rate.