Electrochemical application of cobalt nanoparticles-polypyrrole composite modified electrode for the determination of phoxim

Abstract

In this study, cobalt nanoparticles (CoNPs) were synthesized and cobalt nanoparticles modified glassy carbon electrode (CoNPs/GCE) was prepared by drop coating the nanoparticles on glassy carbon electrode. After preparing polypyrrole modified glassy carbon electrode (PPy/GCE) using electropolymerization of pyrrole in LiClO 4 solution, cobalt nanoparticles-polypyrrole composite modified glassy carbon electrode (CoNPs/PPy/GCE) was fabricated by drop coating the CoNPs on the PPy/GCE. Different characterization techniques such as scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, FTIR spectroscopy, electrochemical impedance spectroscopy and cyclic voltammetry were used to study the morphological structure and electrochemical behavior of the sensors. The results demonstrated that PPy chains interacted with CoNPs through donor-acceptor bonds. Among all the electrodes, CoNPs/PPy/GCE exhibited highest electroactive surface area and lowest electron transfer resistance towards phoxim. Under the optimal conditions, the sensor showed linear relationship between the reduction peak current and the concentration of phoxim in the range of 0.025 μM–12 μM with the detection limit as 4.5 nM. Besides, the composite electrode demonstrated excellent reproducibility, good stability and selectivity towards the possible interfering substances. All of these properties made CoNPs/PPy/GCE a suitable electrochemical sensor for the electrochemical determination of phoxim in water samples using square wave voltammetry.

Non-enzymatic electrochemical sensors based on nanomaterials for detection of organophosphorus pesticide residues

“…This involved modification of ferrocene–thiophene complexes on carbon nanotubes by click chemistry, with synergistic effects increasing the surface area, conductivity and catalytic properties of the electrodes, and the redox reaction of parathion at the electrode surface. Tefera et al 60 prepared a cobalt nanoparticle-polypyrrole modified glassy carbon electrode (CoNPs/PPy/GCE) for the detection of phoxim by drop-coating cobalt nanoparticles (CoNPs) onto polypyrrole modified glassy carbon electrodes (PPy/GCE) made by electrodeposition. Reduction of phoxim occurred at the electrode surface.…”

A portable acetylcholinesterase-based electrochemical sensor for field detection of organophosphorus

“…18 Compared with traditional instruments (gas chromatography mass spectrometry, 19,20 high performance liquid chromatography 21 spectrophotometry, 22 capillary electrophoresis 23 ), electrochemical biosensors are fast in analysis and do not require complex processing, special expertise or expensive equipment. As more and more nanomaterials with excellent properties are synthesized and introduced into the construction of electrochemical sensors, such as metal nanoparticles, [24][25][26] carbon-based nanomaterials, [27][28][29] composite materials [30][31][32][33][34][35][36] etc. Due to their large specic surface area, high reactivity, strong adsorption capacity, good biocompatibility and electrical conductivity, they have been used to stabilize and improve the biosensing interface and amplify the detection signal, which improved the detection performance of the sensors to a new level.…”

Novel Cytochrome P450-3A4 Enzymatic Nanobiosensor for Lapatinib (a Breast Cancer Drug) Developed on a Poly(anilino-co-4-aminobenzoic Acid-Green-Synthesised Indium Nanoparticle) Platform

“…The use of nanoparticles (NPs) in biosensors to identify cancer carries the promise of improving the survival rate of patients. Due to their various properties, nanoparticles have been widely used in sensing systems to detect and monitor different diseases and viruses [ 15 , 16 , 17 , 18 , 19 , 20 , 21 ]. Likewise, there are a variety of approaches that can be used to create these nanoparticles.…”