A reliable alternative approach for the ultra-sensitive detection of l-glutathione with wet chemically synthesized Co3O4-doped SnO2 nanoparticles decorated on a glassy carbon electrode

Abstract

In this study, an electrochemical sensor was fabricated for the non-enzymatic detection of L-glutathione via an electrochemical approach using wet chemically prepared Co₃O₄-doped SnO₂ nanoparticles (NPs) decorated on a glassy carbon electrode (GCE). X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), UV/visible spectroscopy, Brunauer–Emmett–Teller (BET) analysis, and Fourier-transform infrared (FTIR) spectroscopy were carried out for the detailed characterization of the synthesized NPs. The Co₃O₄-doped SnO₂ NPs were deposited onto a GCE, resulting in the proposed L-glutathione sensor, and it was calibrated via plotting current versus the concentration of L-glutathione. The sensor sensitivity (20.9873 μA μM⁻¹ cm⁻²) is obtained from the slope of the calibration plot, considering the surface area (0.0316 cm²) of active NPs on the GCE. In the non-enzymatic detection of L-glutathione, the assembled sensor exhibits a broad linear dynamic range (0.1 mM–0.1 nM), a limit of detection (LOD) of 93.65 ± 4.68 pM, a limit of quantification (LOQ) of 936.5 ± 46.8 pM, appreciable reproducibility, outstanding working-electrode stability, and high efficiency. It is able to detect L-glutathione in real biological samples efficiently. Thus, this is an alternative approach for the reliable detection of chemicals and biochemicals in the environmental and healthcare sectors.