The Mn‐zeolite/Graphite Modified Glassy Carbon Electrode: Fabrication, Characterization and Analytical Applications

Abstract

In this work, low‐cost and environmentally friendly natural zeolite exchanged with Mn2+ cations was used for the first time to modify the glassy carbon electrode with the aim to obtain a fast and simple sensor for voltammetric determination of paracetamol (PAR). The Mn‐zeolite/graphite modified glassy carbon electrode (MnZG−GCE) was prepared by evaporation of solvent from dispersion of the zeolite/graphite mixture with the polymer in acetone. The electrochemical characteristics of MnZG−GCE were conducted by electrochemical impedance spectroscopy and cyclic voltammetry. Compared with graphite modified GCE (G−GCE), MnZG−GCE exhibited better electrochemical parameters, which confirms the superiority of applying zeolite in the proposed sensor. The optimization of the pH‐value of supporting electrolyte and instrumental parameters were carried out. The peak current was proportional to the concentration of PAR in a phosphate buffer saline of pH 6.0 in the range from 0.029 to 0.69 mg L−1 (R=0.9997) with limit of detection of 8.8 μg L−1. Finally, the proposed electrode was successfully applied to determine the paracetamol in pharmaceutical formulation and certified reference materials. The satisfactory recoveries, which ranged from 89.2 to 102.7 %, were obtained for all studied samples. It confirmed the attractiveness of relatively inexpensive, easy to fabricate and non‐toxic MnZG−GCE in determination of PAR in complicated matrixes.

Direct Determination of Peroxide Explosives on Polycarbazole/Gold Nanoparticle-Modified Glassy Carbon Sensor Electrodes Imprinted for Molecular Recognition of TATP and HMTD

“…The three processes leading to the voltammetric background signal build-up are charging of the electrical double layer, faradaic reactions of impurities (e.g., of the electrolyte ions adsorbed in the pores of the electrode surface), and possible oxidation/reduction of the electrode surface. 38 Since an appreciable increase in background current is usually associated with a higher value of capacitive (non-Faradaic) current 39 and acetone may affect the characteristics of a double-layer capacitor by giving rise to a relatively low capacitance but high pore resistance of the electrode, 40 acetone gave the lowest and stable current response among some common solvents and was consequently selected as the optimal solvent for the square-wave voltammetric analysis of cosmetic products using a GC electrode. 41 In our case, the background peak in routine analyses was assumed to emerge from the baseline solution medium and did not significantly vary to affect measurements.…”

Graphene oxide quantum dots immobilized on mesoporous silica: preparation, characterization and electroanalytical application

“…The background was subtracted from each voltammogram, as recommended by convention. 51 The limit of detection (LOD) and limit of quantication (LOQ) were calculated as follows: LOD ¼ 3S b /b, and LOQ ¼ 10S b /b, where S b is the standard deviation of the blank (n ¼ 10) and b is the slope of the calibration curve. For organic analytes, the octane-water distribution coefficients (log P) were found from the PubChem database.…”

Sensitive and selective determination of paracetamol in antipyretic children's syrup with a polyglycine modified glassy carbon electrode

“…53 In voltammetry, the main element is the working electrode, where the depolarizer is reduced or oxidized. 54 A commonly used sensor in voltammetry for the determination of ACOP is modied glassy carbon. It has high chemical inertness, good electrochemical stability, extremely low gas permeability, an extremely low coefficient of thermal expansion, and good biocompatibility.…”

“…In voltammetry, the main element is the working electrode, where the depolarizer is reduced or oxidized. 54…”