Deciphering Highly Sensitive Non-Enzymatic Glucose Sensor Based on Nanoscale CuO/PEDOT-MoS₂Electrodes in Chronoamperometry

Abstract

The present work demonstrates fabrication of a non-enzymatic glucose sensor based on CuO nanoparticles deposited over poly(3,4-ethylenedioxythiophene) (PEDOT) conducting polymer infiltrated with MoS2. Structural, morphological and elemental analysis of the fabricated sensor electrodes were performed via different characterization techniques like x-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), elemental dispersive x-ray spectroscopy (EDX), and Fourier transform infra-red spectroscopy (FTIR). The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) studies of the hybrid nanoelectrode (CuO/PEDOT-MoS2) exhibited better redox activity and electron transfer kinetics, as compared with the CuO/PEDOT and CuO only systems. Moreover, the electrochemical parameters of all the systems were determined and compared accordingly while CuO/PEDOT-MoS2 hybrid system offers a significant enhancement in the electroactive area (~1.47 cm- 2) and rate constant (0.76 s-1) towards oxidizing glucose into gluconic acid. In the CV responses, an augmented activity was monitored at +0.6 V which was considered as the dc bias potential in the chronoamperometric experiment for detecting glucose. The sensor electrode yielded a low LOD of 0.046 μM and with a sensitivity magnitude as high as 829 µA mM-1 cm-2 over a wide linear range, between 30 μM to 1.06 mM of glucose concentration.

Synthesis of Copper Nanostructures for Non-Enzymatic Glucose Sensors via Direct-Current Magnetron Sputtering

“…The diffusion coefficient of glucose was determined according to the Cottrell Equation (1): I = nFACD 1/2 π −1/2 t −1/2 where n is the number of transferred electrons, F is the faraday number, A is the area of the electrode, C is the concentration of the glucose, and D is the diffusion coefficient. From the slope of the resulting plots of I vs. t −1/2 (see Figure 9 B) at different glucose concentrations, the average diffusion coefficient was calculated to be 4.25 × 10 −4 cm 2 s −1 [ 37 ].…”

Precise detection of IgG molecules using AuNP anchored, PEDOT-MoS 2 based electrochemical sensor

“…Prior to deposition of AuNPs, rst the PEDOT-MoS 2 lm was deposited over ITO glass by electrochemical technique [25]. The synthesis procedure of electrodeposited PEDOT and PEDOT-MoS 2 lm, are discussed in the supplementary section.…”