Samarium tungstate anchored on graphitic carbon nitride composite: A novel electrocatalyst for the ultra-selective electrocatalytic detection of 8-hydroxy-5-nitroquinoline in river water and biological samples

Herein we report a rapid and sensitive electrochemical sensor for the detection of 8-Hydroxy-5-nitroquinoline (HN) based on a fabricated glassy carbon electrode (GCE) modified with samarium tungstate anchored on graphitic carbon nitride (SW/g-CN) composite. A simple ultrasonic approach was used to synthesis a SW/g-CN composite. The physicochemical properties of the as-prepared composite material were determined by using Xray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). Following that, the sample's morphology information was determined by using field emission scanning electron microscopy (FESEM) study. Additionally, the electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and differential pulse voltammetry (DPV) studies were used to determine the electrochemical activity of the as-prepared composite. The developed sensor has a low detection limit (LOD) and a high sensitivity of about 1.2 nM and 1.24 mu A mu M-1 cm(-2) for the detection of HN. Along with that, the SW/g-CN composite modified GCE exhibits exceptional reproducibility, long-term stability, and selectivity. The designed sensor showed acceptable recovery values for the determination of HN in human urine, human blood serum, and river water samples.

Automated summary

In this study, a rapid and sensitive electrochemical sensor based on SW/g-CN composite modified glassy carbon electrode was developed for the detection of 8-Hydroxy-5-nitroquinoline (HN). The sensor exhibited low detection limit and high sensitivity, along with exceptional reproducibility, stability, and selectivity. Acceptable recovery values were observed for the determination of HN in human urine, human blood serum, and river water samples.