Fabrication and optimization of polypyrrole/cerium oxide/glassy carbon sensing platform for the electrochemical detection of flupirtine

In spite of single nanomaterials, nanocomposites have come to be the superior modifying materials for electrochemical sensing. Herein, the highly sophisticated and sensitive voltammetric sensor of polypyrrole/cerium oxide/glassy carbon electrode (Ppyr/CeO2/GCE) has been fabricated for the electrochemical analysis of flupirtine maleate (FPM). Prior to the fabrication, the synthetic Ppyr/CeO2 material and its constituents viz., Ppyr and CeO2 were spectrally characterized by FTIR, XRD, and SEM to confirm the successful synthesis. After the fabrication of the Ppyr/CeO2/GCE sensor, it together with its corresponding forms i.e., CeO2/GCE and Ppyr/GCE including bare GCE was characterized by voltammetry and electrochemical impedance spectroscopy (EIS). The electrode characteristics such as charge transfer resistance, heterogeneous electron transfer (HET) rate constant, ($$k_{{{\text{eff}}}}^{0}$$) and surface area suggest that the designed electrochemical sensor has got the conductivity (sensitivity) par excellence as compared to CeO2/GCE, Ppyr/GCE and bare GCE. The fabricated probe after characterization was optimized for the detection of the FPM by voltammetry and found to show a direct correlation between the oxidation current and the FPM concentration varying from 100 ng mL−1 to 500 ng mL−1 having correlation coefficient (r2) of 0.9940. By measuring the calibration curve, the fabricated Ppyr/CeO2/GCE sensor was found to reach the minimum limit of detection (LOD) i.e., 26.76 ng mL−1 and minimum limit of quantification (LOQ) i.e., 89.20 ng mL−1, for FPM, thereby showing the sensitivity par excellence in terms of conductivity. Fabrication of Ppyr/CeO2/GCE voltammetric sensor