Electrochemical Determination of Chlorpyrifos on a Nano-TiO₂/Cellulose Acetate Composite Modified Glassy Carbon Electrode

Abstract

A rapid and simple method of determination of chlorpyrifos is important in environmental monitoring and quality control. Electrochemical methods for the determination of pesticides are fast, sensitive, reproducible, and cost-effective. The key factor in electrochemical methods is the choice of suitable electrode materials. The electrode materials should have good stability, reproducibility, more sensitivity, and easy method of preparation. Mercury-based electrodes have been widely used for the determination of chlorpyrifos. From an environmental point of view mercury cannot be used. In this study a biocompatible nano-TiO2/cellulose acetate modified glassy carbon electrode was prepared by a simple method and used for the electrochemical sensing of chlorpyrifos in aqueous methanolic solution. Electroanalytical techniques such as cyclic voltammetry, differential pulse voltammetry, and amperometry were used in this work. This electrode showed very good stability, reproducibility, and sensitivity. A well-defined peak was obtained for the reduction of chlorpyrifos in cyclic voltammetry and differential pulse voltammetry. A smooth noise-free current response was obtained in amperometric analysis. The peak current obtained was proportional to the concentration of chlorpyrifos and was used to determine the unknown concentration of chlorpyrifos in the samples. Analytical parameters such as LOD, LOQ, and linear range were estimated. Analysis of real samples was also carried out. The results were validated through HPLC. This composite electrode can be used as an alternative to mercury electrodes reported in the literature.

Interfacial charge-transfer process across ZrO2-TiO2 heterojunction and its impact on photocatalytic activity

“…The bands at wavenumbers of 563 cm -1 and 559 cm -1 are related to the vibrations of Ti-O-Ti and Zr-O-Zr bonds [33][34]. Additionally, the band at 2300 cm -1 attributed to CO2 is associated with environmental conditions in which the measurements are carried out and the band at 2900 cm -1 could be assigned to stretching vibration of C-H provoked by residues of Zr and Ti precursors [35]. oxides [40][41][42][43].…”

A novel sensing layer based on metal–organic framework UiO-66 modified with TiO2–graphene oxide: application to rapid, sensitive and simultaneous determination of paraoxon and chlorpyrifos

“…Also, TiO 2 inserted on GO (TGO/GCE) could increase the response of the designed sensor towards the targets compared to GO/GCE and GO@UiO-66/GCE due to the high affinity of nano-TiO 2 for phosphate groups and carboxylic groups can bind on the TiO 2 nanoparticles and enhance the electron transfer processes in the electrochemical sensing for detection of organophosphate pesticides. 27 The effects of supporting electrolytes and pH were investigated using SWV of the peak potentials and peak currents of POX and CPF. TGO@UiO-66/GCE was used for POX (50.0 nM), and CPF (50.0 nM) reduction with different supporting electrolytes and the maximum response was obtained in 0.1 M BR buffer/acetonitrile (9/1).…”

“…25 In another study, significant electrocatalytic activity was obtained by TiO 2 /graphene for simultaneous detection of adenine and guanine. 26 By considering the high performance of each individual component, and taking the high affinity of nano TiO 2 for phosphate groups (such as in POX and CPF) into account, 27 the main aim of the present work is modification of a glassy carbon electrode with the TiO 2 @GO/UiO-66 nanocomposite which is prepared through a straightforward sonication method and this novel sensing platform has been employed for the simultaneous determination of POX and CPF in real samples.…”

Development of polyindole/tungsten carbide nanocomposite-modified electrodes for electrochemical quantification of chlorpyrifos

“…The nanocomposites employed for modification of GCE for OPs detection were zeolite [24], ZrO 2 [25], Au/Graphene [26,27], ZrO 2 [28], SWNT/GO [29], MWCNT [30], Au/Pt [31] and ZrO 2 /MWCNT [32]. The nanomaterials used for detection of CHL were graphene [17], MWCNT [33][34][35], with nano-TiO 2 [36], carbon nitride [37], ferrocene [38], CuO [39]. Conducting polymers have been used as such or in the form of their nanocomposites for detection of CHL through SWV [24,30].…”