Synthesis and electrochemical properties of environmental free L-glutathione grafted graphene oxide/ZnO nanocomposite for highly selective piroxicam sensing

A simple and reliable strategy was proposed to engineer the glutathione grafted graphene oxide/ZnO nanocomposite (glutathione-GO/ZnO) as electrode material for the high-performance piroxicam sensor. The prepared glutathione-GO/ZnO nanocomposite was well characterized by X-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). The novel nanocomposite modified electrode showed the highest electrocatalytic activity towards piroxicam (oxidation potential is 0.52 V). Under controlled experimental parameters, the proposed sensor exhibited good linear responses to piroxicam concentrations ranging from 0.1 to 500 mu M. The detection limit and sensitivity were calculated as 1.8 nM and 0.2 mu A/mu M.cm(2), respectively. Moreover, it offered excellent selectivity, reproducibility, and long-term stability and can effectively ignore the interfering candidates commonly existing in the pharmaceutical tablets and human fluids even at a higher concentration. Finally, the reported sensor was successfully employed to the direct determination of piroxicam in practical samples. (C) 2020 Xi'an Jiaotong University. Production and hosting by Elsevier B.V.

Automated summary

A simple and reliable strategy was proposed to engineer the glutathione grafted graphene oxide/ZnO nanocomposite as electrode material for the high-performance piroxicam sensor. The nanocomposite modified electrode exhibited the highest electrocatalytic activity towards piroxicam, with good linear responses, low detection limit, and high sensitivity. The sensor showed excellent selectivity, reproducibility, and long-term stability, effectively ignoring interfering candidates commonly existing in pharmaceutical tablets and human fluids even at higher concentrations.