Ionic liquid based high performance electrochemical sensor for ascorbic acid in various foods and pharmaceuticals

Abstract

In the present study, 1-butyl-3-methyl imidazolium tetra fluoroborate ionic liquid (IL), boron nitride (BN) and magnetite nanoparticles (Fe3O4NPs) based nanocomposite (IL-BN-Fe3O4NPs) was successfully synthesised and used to fabricate glassy carbon electrode (GCE) for the determination of ascorbic acid (AA). The nanocomposite was characterized by Fourier transformation infrared spectroscopy (FTIR), x-ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM), electron diffraction spectroscopy (EDS) and transmission electron microscopy (TEM) techniques to observe the surface morphology. Cyclic voltammetry (CV) was performed to assess the electrochemical performance of IL-BN-Fe3O4NPs/GCE towards ascorbic acid (AA) in 0.1M phosphate buffer solution (PBS) at pH7. The CV results obtained reveal that the significant enhancement of anodic peak current with increased sensitivity and conductivity. The differential pulse voltammetric results obtained indicates the linear increment of electrochemical signals with an increase in the concentration of AA in the range of 1–12μM. Based on the calibration plot, limit of detection and limit of quantification were calculated and found to be 0.042 and 0.139μM respectively. The electrochemical sensor showed outstanding sensitivity, selectivity, repeatability and stability. In addition to this IL-BN-Fe3O4NPs/GCE sensor was practically applied for the routine analysis of AA in various food and pharmaceutical samples.