Title :

Simultaneous Hydrolysis and Detection of Organophosphate by Benzimidazole Containing Ligand-Based Zinc(II) Complexes

Author(s) :

Mersal, Gaber [Auteur]
Taif University [TU]
El-Sheshtawy, Hamdy [Auteur]
Kafrelsheikh University
Amin, Mohammed [Auteur]
Taif University [TU]
Mostafa, Nasser [Auteur]
Suez Canal University
Mezni, Amine [Auteur]
Taif University [TU]
Faculté des Sciences de Bizerte [Université de Carthage]
Alharthi, Sarah [Auteur]
Taif University [TU]
Boukherroub, Rabah [Auteur]
NanoBioInterfaces - IEMN [NBI - IEMN]
Ibrahim, Mohamed [Auteur]
Taif University [TU]

Journal title :

Crystals

Pages :

714

Publisher :

MDPI

Publication date :

2021

ISSN :

2073-4352

English keyword(s) :

benzimidazole containing Zn(II) ligand
biomimetic
organophosphate hydrolysis
carbon paste electrode
electrochemical detection
fenitrothion
parathion

HAL domain(s) :

Chimie/Chimie de coordination
Chimie/Chimie analytique
Sciences de l'environnement/Ingénierie de l'environnement

English abstract : [en]

The agricultural use of organophosphorus pesticides is a widespread practice with significant advantages in crop health and product yield. An undesirable consequence is the contamination of soil and groundwater by these ...
Show more >The agricultural use of organophosphorus pesticides is a widespread practice with significant advantages in crop health and product yield. An undesirable consequence is the contamination of soil and groundwater by these neurotoxins resulting from over application and run-off. Here, we design and synthesize the mononuclear zinc(II) complexes, namely, [Zn(AMB)2Cl](ClO4) 1 and [Zn(AMB)2(OH)](ClO4) 2 (AMB = 2-aminomethylbenzimidazole), as artificial catalysts inspired by phosphotriesterase (PTE) for the hydrolysis of organophosphorus compounds (OPs) and simultaneously detect the organophosphate pesticides such as fenitrothion and parathion. Spectral and DFT (B3LYP/Lanl2DZ) calculations revealed that complexes 1 and 2 have a square-pyramidal environment around zinc(II) centers with coordination chromophores of ZnN4Cl and ZnN4O, respectively. Both 1 and 2 were used as a modifier in the construction of a biomimetic sensor for the determination of toxic OPs, fenitrothion and parathion, in phosphate buffer by square wave voltammetry. The hydrolysis of OPs using 1 or 2 generates p-nitrophenol, which is subsequently oxidized at the surface of the modified carbon past electrode. The catalytic activity of 2 was higher than 1, which is attributed to the higher electronegativity of the former. The oxidation peak potentials of p-nitrophenol were obtained at +0.97 V (vs. Ag/AgCl) using cyclic voltammetry (CV) and +0.88 V (vs. Ag/AgCl) using square wave voltammetry. Several parameters were investigated to evaluate the performance of the biomimetic sensor obtained after the incorporation of zinc(II) complex 1 and 2 on a carbon paste electrode (CPE). The calibration curve showed a linear response ranging between 1.0 μM (0.29 ppm) and 5.5 μM (1.6 ppm) for fenitrothion and 1.0 μM (0.28 ppm) and 0.1 μM (0.028 ppm) for parathion with a limit of detection (LOD) of 0.08 μM (0.022 ppm) and 0.51 μM (0.149 ppm) for fenitrothion and parathion, respectively. The obtained results clearly demonstrated that the CPE modified by 1 and 2 has a remarkable electrocatalytic activity towards the hydrolysis of OPs under optimal conditions.Show less >

Language :

Anglais

Popular science :

Non

Collections :

• Institut d'Électronique, de Microélectronique et de Nanotechnologie (IEMN) - UMR 8520

Source :

Harvested from HAL