Electrochemical Analysis of Endocrine Disrupting Chemicals over Carbon Electrode Modified with Cameroon's Clay

Abstract

A simple and sensitive electroanalytical method was developed to determine the Endocrine Disrupting chemical 4-tert-octylphenol on clay modified carbon paste electrode (Clay/CPE). The electrochemical response of the proposed electrode was studied by means of cyclic and square wave voltammetry. The structural morphology of the modified electrode was characterized by SEM/EDX and XRD techniques. It has been found that the oxidation of 4-tert-octylphenol on the clay/CPE displayed a well-defined oxidation peak. Factors influencing the detection processes were optimized. 4-tert-octylphenoloxidation occurred through a surface process involving its adsorption on the clay/CPE. Under these optimal conditions, a linear relation between concentrations of 4-tert-octylphenoland current response was obtained over the range of 7.26 × 10 −6 to 3.87 × 10 −7 with a detection limit and a quantification limit of 9.2 × 10 −7 M and 3.06 × 10 −6 M, respectively. The correlation coefficient is 0.9963. The modified electrode showed suitable sensitivity, high stability and an accurate detection of 4-tert-octylphenol.The modified electrode also relevant suitable selectivity for various phenolic estrogenic compounds such as 4-Nonylphenol and Bisphenol A.

Simple Voltammetric Method for Nano Estimation of Etilefrine Hydrochloride Based on Environmentally Friendly Montmorillonite Natural Clay

“…This may be due to the enhancement of the surface area of the modified electrodes and decrease interface electron transfer resistance, 3738 which could effectively increase the rate of electron transfer between electrode surface and K 4 Fe(CN) 6 species. 26,28,37,38 Linear dependence of the anodic peak currents (i pa ) to the square root of scan rate (v 1/2 ) was achieved for bare CPE and Na-MMT modified CPEs, (e.g., Fig. 4, Inset).…”

“…5, curve a). This indicates the electrocatalytic activity 21,28,37 and the higher adsorptive ability of MMT/CPE toward EF.HCl which may be attributed to its higher active surface area and increasing number of the catalytically active sites on its surface. 20 Very likely, the presence of permanent negatively charged sites within the clay yields a promoting effect toward EF.HCl as a result of favorable electrostatic interactions with the positively charged or protonated EF.HCl molecules.…”

“…Because of the specific properties of mineral clays viz., carries net charge, exchangeable cations and porosity, clay-modified electrodes have also been of interest for several decades and have been extensively studied up to date. [20][21][22][23][24][26][27][28] Montmorillonite is the most familiar and common member of the smectite group. The pore-like structure of MMT natural clay contains layers made up of two tetrahedral silica sheets fused to an edge-shared octahedral sheet of alumina.…”

“…Na-MMT toward oxidation of EF.HCl. 21,28,37 Increasing Na-MMT up to 7%(w/w) decreasing charge-transfer resistances and facilitate the charge-transfer rate between the electron surface and adsorbed electroactive species. 20,26,28,37,38 However, at 9%(w/w)Na-MMT/CPE, an obvious increase in charge transfer resistance of the electrode surface was again observed (250.54 ± 2.42 ) which may be due to low conductivity of Na-MMT clay (which can obstruct electron transfer at higher percentages).…”