An enzyme free detection of L-Glutamic acid using deposited CuO.GdO nanospikes on a flat glassy carbon electrode

Abstract

Here, copper oxide doped gadolinium oxide nanospikes (CuO.GdO NSs) were prepared by hydrothermal process at low temperature in an alkaline phase. CuO.GdO NSs were characterized by conventional techniques, for example Fourier Transform Infrared Spectroscopy (FTIR), UV–visible Spectroscopy (UV–visible), powder X-ray diffraction (XRD), Field-Emission Scanning Electron Microscopy (FESEM) equipped with X-ray electron dispersive spectroscopy (XEDS), and X-ray photoelectron spectroscopy (XPS). A sensitive and selective L-Glutamic acid sensor was developed with deposition of a thin-layer of doped NSs onto a glassy carbon electrode (GCE, surface area = 0.0316 cm2) by using coating 5% Nafion binder. Enhanced electrochemical performances such as higher sensitivity, lower limit of detection, linear dynamic range, and long-term stability of fabricated L-Glutamic acid sensor were achieved by a reliable current-voltage system. Calibration curve was found linear (R2 = 0.9982) over a wide range of L-Glutamic acid concentration (100.0 pM ~100.0 mM). Based on SNR ~3, sensitivity and limit of detection of sensor were calculated as sensitivity (569.62 μAnM−1cm−2), and LOD (166.67 pM) respectively. This expected CuO.GdO NSs/Nafion/GCE sensor probe is used for the real sample analysis (Human and rabbit serum) and found acceptable results. This proposed electrochemical approach can be a pioneer sensor development in enzyme less sensor improvement for assessment of bio-molecules in health care and biomedical fields in broad scales.