Fabrication of Tetra-Substituted Copper(II) Phthalocyanine-Graphene Modified Pencil Graphite Electrode for Amperometric Detection of Hydrogen Peroxide

Abstract

In this study, tetra-substituted copper(II) phthalocyanine-graphene modified pencil graphite electrode (CuPc-Gr/PGE) was developed for the amperometric determination of hydrogen peroxide (H2O2) for the first time in the literature. The developed non-enzymatic electrode platform was electrochemically characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) methods. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) methods were also used for surface characterization of the modified electrode. The response to H2O2 at the working potential of −0.4 V is linear in the 0.1 μM to 100 μM concentration range in PBS pH 7.0. The limit of detection (LOD) and limit of quantitation (LOQ) are 0.045 and 0.15 μM, respectively. Good selectivity was observed within physiological interference species such as ascorbic acid, dopamine, uric acid, and glucose. Additionally, amount of H2O2 was determined using the novel produced non-enzymatic sensor with satisfactory results in beverage samples. These consequences imply that the CuPc-Gr/PGE displays effective electrocatalytic activity for the reduction of H2O2, indicating it has capability use for the detection of H2O2.

Cost‐effective and Facile Production of a Phosphorus‐doped Graphite Electrode for the Electrochemical Determination of Pyridoxine

“…Electrochemical impedance spectroscopy is known to be among the methods used to study the capacitive and surface properties of the constructed sensor [25, 26, 27]. 2.5 mmol L −1 [Fe(CN) 6 ] 3−/4− +0.1 mol L −1 KCl solution was used during EIS measurements.…”

“…We can also say that the decrease in peak current can be attributed to the forming of negatively charged functional groups on the surface of the P-doped/PGE and the electrostatic repulsion with Fe(CN) 6 3À /4À groups. Electrochemical impedance spectroscopy is known to be among the methods used to study the capacitive and surface properties of the constructed sensor [25,26,27]. 2.5 mmol L À 1 [Fe(CN) 6 ] 3À /4À + 0.1 mol L À 1 KCl solution was used during EIS measurements.…”

“…Lastly, time optimization (25,50,100,150,200, and 250 seconds) was performed at previously selected concentration and potential (0.1 M H 3 PO 4 , and + 2.0 V). As seen in the concentration and potential studies, while the peak current increased from 25 seconds to 100 seconds, the decrease in peak current was seen after 100 seconds and the peak shape was distorted (Figure S4c).…”

Sensitive Electrochemical Determination of NADH Using an Electrode Fabricated by Intercalation of Tetrabutylammonium Ions Into Graphite Electrode

“…Figure 2c shows the Nyquist plot of Bare/ PGE and TBA + /PGE measured in 0.1 M KCl solution containing 5.0 mM of [Fe(CN) 6 ] 3À /4 . The spectra were fitted to a known equivalent circuit model which was widely reported in the literature [44][45][46] as shown in Figure 2c inset. A large semicircle at high frequencies observed in the results recorded for Bare/PGE can be interpreted as the presence of a slow electron transfer rate on the unmodified surface.…”

“…Measurements (intra-day and inter-day) were recorded to examine the reproducibility and repeatability of the TBA + /PGE [46,60]. To examine intra-day reproducibility performance, amperometric current-time measurements of 100 μM NADH were conducted using ten different TBA + /PGEs prepared just prior to analysis.…”