Detection Of Methyl Parathion Research Articles

AuNPs and graphdiyne nanocomposite as robust electrocatalyst for methyl parathion detection in real samples.

The present work describes a simple and rapid synthesis method of gold nanoparticles and graphdiyne (AuNPs@GDY) nanocomposites including porous structure. Moreover, the synthesized AuNPs@GDY material was decorated on the glassy carbon electrode (GCE) with a drop coating method to construct a non-enzymatic electrochemical pesticides sensor. The micro-morphology and elemental composition of the materials were characterized by transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). The electrocatalysis and conductivity of the material were studied with cyclic voltammetry (CV) and impedance method, respectively. The properties of the sensor were investigated by CV and differential pulse voltammetry (DPV). The results showed that AuNPs@GDY exhibited excellent electrocatalytic ability for methyl parathion in a wide linear range (from 0.25ng/mL to 24.43μg/mL) and low limit of detection value (6.2pg/mL). Furthermore, the DPV method used in this paper was accurate and sensitive, and could be used for routine quality control of methyl parathion in kiwi fruit and tomato samples.

Portable and durable sensor based on porous MOFs hybrid sponge for fluorescent-visual detection of organophosphorus pesticide

Pesticide residues have raised serious public concern towards agriculture, environment and food safety. Recently, metal-organic frameworks (MOFs) have been employed as promising recognition and signal generation elements in sensors for pesticide detection. However, the general format of tiny particles with poor dispersity brings obstacles to detection operation and the improvement of sensing performance. Here, we report a sensor based on porous MOFs hybrid sponge for fluorescent-visible detection of methyl parathion. Benefiting from the intermediate of adhesive and porous fibrin film, MOFs are loaded with good dispersion and accessibility, thereby endowing the sensor with a rapid response time of 10-min, a wide linear detection range of 50–2500 μg L-1, and a low limit of detection of 4.95 μg L-1. Moreover, the hybrid sensor presented superior durability and anti-interference ability to the detection in complex conditions, including organic solvents, acidic solution, high temperature, and even chemical interferences. This hybrid not only provides a new construction strategy for a nanomaterial-based sensor, but also permits a portable and durable route for the detection.

Functionalised multi-walled carbon nanotubes-based electrochemical sensor: synergistic effect of graphitisation and carboxylation on detection performance of methyl parathion

ABSTRACT Efficient and sensitive detection of methyl parathion (MP), an insecticide, is of great significance to food safety and healthy life. In this work, functionalised multi-walled carbon nanotubes after graphitisation and carboxylation (FCNTGC) were applied as a sensitising agent to fabricate the glassy carbon electrode (GCE). The obtained FCNTGC/GCE sensor was successfully used for the sensitive detection of MP. The graphitisation of carbon nanotubes contributes to enhancing the conductive property, and the carboxylation of carbon nanotubes contributes to improving the dispersibility of carbon material. The combination of graphitisation and carboxylation could effectively enhance the electrochemical sensing property towards MP. The fabricated FCNTGC/GCE sensor showed a low limit of detection of 0.00306 μM in a linear concentration range of 0.01–10 µM. In addition, good repeatability and reproducibility could be obtained for the MP detection with the fabricated sensor.

Electrochemical sensing platform based on graphitized and carboxylated multi-walled carbon nanotubes decorated with cerium oxide nanoparticles for sensitive detection of methyl parathion

We proposed a low-cost ultrasonic-assisted strategy to prepare the graphitized and carboxylated carbon nanotubes (GR-MWCNTs-COOH) and cerium oxide (CeO2) nanoparticles nanocomposite, which was applied to fabricate the GR-MWCNTs-COOH@CeO2/GCE sensor for the electrochemical detection of methyl parathion (MP). GR-MWCNTs-COOH with graphitization and carboxylation showed excellent conductivity property, large surface area, and gratifying hydrophilicity. Graphitization enhanced the electrical conductivity of MWCNTs, and carboxylation promoted the homogeneous dispersion of MWCNTs. The double-functionalization of MWCNTs helped form the interconnected carbon nanotubes conductive network. CeO2 nanoparticles with good catalytic ability possessed high enrichment capability of MP because of the good affinity between CeO2 and phosphate groups. Moreover, the double-functionalized GR-MWCNTs-COOH not only promoted the uniform dispersion of CeO2 nanoparticles but also compensated for the poor electrical conductivity of CeO2 nanoparticles. The GR-MWCNTs-COOH@CeO2/GCE sensor presented a low detection of limit of 0.0285 μM (MP concentration range: 0.01–10 μM). The satisfactory reproducibility, repeatability, and anti-interference were obtained at the fabricated nanohybrid sensor. When applied for the MP determination in spinach and cabbage samples, the low RSD values of 1.71–4.25% and satisfactory recoveries of 95.8–100.7% could be achieved at the GR-MWCNTs-COOH@CeO2/GCE sensor. This work provided an important reference for the design of high-performance MP sensor.

Application of Ni-Al Layered Double Hydroxides/Graphene Composites for Highly Efficient Electrochemical Detection of Methyl Parathion

Application of Ni-Al Layered Double Hydroxides/Graphene Composites for Highly Efficient Electrochemical Detection of Methyl Parathion

Electrochemical Studies of LbL Films With Dawson Type Heteropolyanion Glassy Carbon Electrode Sensor Modified for Methyl Parathion Detection

Rapid methyl parathion detection was measured using a fabricated glassy carbon electrode (GCE) sensor designed using the layer-by-layer (LBL) method. Multilayer assemblies were developed on the glassy carbon electrode by alternating depositions of anions and cations in which a Dawson Type Polyoxometalate β-K6[(P2W18O62·H2O)]·14H2O (∼P2W18 POM) and polyethyleneimine (PEI) stabilized silver nanoparticles (∼PEI-AgNPs) acted as anions and cations, respectively. The redox behavior of P2W18 POM within LBL assembly was carried out via cyclic voltammetry. This LBL assembly was thoroughly characterized by UV-Visible, FT-IR, XRD, AFM, and SEM techniques. The fabricate GCE sensor was investigated for the electrocatalytic activity to detect methyl parathion. The results clearly showed that the fabricated GCE sensor was successfully synthesized. More interestingly, the current response for detecting methyl parathion was found to be less than 1 ppm, proving that this fabricated GCE sensor may exhibit potential applications in the detection of targeted pesticide.

Wafer-Scale Fabrication and Transfer of Porous Silicon Films as Flexible Nanomaterials for Sensing Application.

Flexible sensors are highly advantageous for integration in portable and wearable devices. In this work, we propose and validate a simple strategy to achieve whole wafer-size flexible SERS substrate via a one-step metal-assisted chemical etching (MACE). A pre-patterning Si wafer allows for PSi structures to form in tens of microns areas, and thus enables easy detachment of PSi film pieces from bulk Si substrates. The morphology, porosity, and pore size of PS films can be precisely controlled by varying the etchant concentration, which shows obvious effects on film integrity and wettability. The cracks and self-peeling of Psi films can be achieved by the drying conditions after MACE, enabling transfer of Psi films from Si wafer to any substrates, while maintaining their original properties and vertical alignment. After coating with a thin layer of silver (Ag), the rigid and flexible PSi films before and after transfer both show obvious surface-enhanced Raman scattering (SERS) effect. Moreover, flexible PSi films SERS substrates have been demonstrated with high sensitivity (down to 2.6 × 10−9 g/cm2) for detection of methyl parathion (MPT) residues on a curved apple surface. Such a method provides us with quick and high throughput fabrication of nanostructured materials for sensing, catalysis, and electro-optical applications.

Rapid determination of methyl parathion in vegetables using electrochemical sensor fabricated from biomass-derived and β-cyclodextrin functionalized porous carbon spheres

Porous carbon spheres (PCS) derived from expired sugarcane juice (SJ) and modified with β-cyclodextrin (β-CD) were used for the fabrication of SJPCS@β-CD/GCE sensor with glassy carbon electrode (GCE) to detect methyl parathion (MP). SJPCS with interconnected porous structure exhibits excellent electrical conductivity, strong adsorption property, and high specific surface area, while β-CD with molecular recognition property achieves the uniform dispersion of SJPCS and promotes the recognition and adsorption of MP molecules. Thanks to the synergistic combination of SJPCS and β-CD, the SJPCS@β-CD/GCE sensor exhibited respectable MP determination performance with low limit of detection of 5.87 nM in the MP concentration range of 0.01–10 µM. For the MP detection in vegetables (onion, cabbage, spinach), the fabricated sensor showed good practicability with adequate relative standard deviation of 1.06% to 4.25% and satisfactory recoveries of 96.5 to 100.5%. A promising strategy for the rapid determination of methyl parathion in food products was developed.

Zirconia nanofibers-loaded reduced graphene oxide fabrication for specific electrochemical detection of methyl parathion

Yttrium-stabilized zirconia@reduced graphene oxide (YSZ@rGO) nanofibers with uniform porous structure were prepared by electrospinning and thermal reduction process. On this basis, PEDOT/YSZ@rGO electrode was fabricated via the electrodeposition for sensitive detection of methyl parathion (MP). Among this, YSZ exhibited outstanding adsorption, rGO improved electron mobility and PEDOT enhanced electrocatalytic properties. The electrochemical impedance spectroscopy (EIS), square wave voltammetry (SWV) and cyclic voltammetry (CV) demonstrated the successful preparation of the sensor. The pH value of the buffer, the pre-deposition time of the working electrode, and the adsorption time have been optimized. Under the optimum condition, the detection limit of the sensor is 1.57 ng·mL−1 (S/N = 3), and the linear detection ranges from 5 to 4000 ng·mL−1, which is superior to most related electrochemical sensors. Furthermore, the sensor exhibits good anti-interference, reproducibility, stability, and satisfactory recovery in real sample, indicating wide commercial applications in detecting food safety and monitoring wastewater emission.

Rational design of 3D N-doped graphene with a holey structure as a bifunctional electrode for sensitive methyl parathion detection and supercapacitors.

N-doped graphene with nano-sized holes possesses abundant electrochemically active sites at the exposed edge and an open porous structure, leading to a better electrochemical performance and faster electron and ion transport than the basal planes in graphene. In this study, three-dimensional graphene with a porous structure and abundant doped N (3d-NHG) were synthesized as bifunctional electrodes for methyl parathion (MP) detection and supercapacitors. The roles of N-doping and the holey construction in the electrochemical performance of the 3d-NHG were systematically investigated through a combined theory-experiment strategy. The 3d-NHG-based electrochemical sensor successfully detected methyl parathion in the range of 38 nm-380 μM with a low detection limit (2.27 nM) and superior sensitivity. Furthermore, the 3d-NHG also demonstrated potential for use in supercapacitors with a specific capacitance of 207 F g-1 at 1 A g-1 and excellent rate capability (76% capacitance retention at 10 A g-1). Density functional theory calculations revealed that the exposed carbon sites at the edge are the reactive sites for species adsorption. Moreover, the holey structure in 3d-NHG plays a dominating role in electrochemical processes and in the enhanced electrocatalysis. This work provides guidance for the rational design of high-performance bifunctional electrodes for MP detection and supercapacitors by defect engineering.

Graphene/g-carbon nitride (GO/g-C3N4) nanohybrids as a sensor material for the detection of methyl parathion and carbendazim

The widespread use of methyl parathion (MP) and carbendazim (CBZ) as pesticide molecules for controlling pests and protect crops has added pollution issues; excess usage of these can lead to atmospheric pollution through contaminating water and soil sources. In the present study, detection of these compounds at the trace level was achieved by employing graphene oxide (GO) and graphitic carbon nitride (g-C3N4) nanohybrid electrode assembly (GO/g-C3N4/GCE). The X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), and Atomic Force Microscopy (AFM) techniques were also used to characterize the materials developed to reveal their purity, crystal structure, and morphology. The complete voltammetric behavior of these analytes was investigated using cyclic voltammetic (CV) and square wave voltammetry (SWV) techniques. The influence of pH was studied and it was noticed that electrochemical response was the highest at pH 7.0 for MP and at pH 4.2 for CBZ. Density Functional Theory (DFT) calculations could help us to understand the adsorption behavior of MP and CBZ onto the GO and g-C3N4 before their degradation due to the electrochemical reactions. SWV technique was helpful in the trace level detection of MP and CBZ. Linearity plots were obtained in the range of concentration from 8.0 × 10−8 M to 1.0 × 10−4 M with a limit of detection 0.824 nM for MP and 1.0 × 10−8 M to 2.5 × 10−4 M for CBZ with the detection limit of 2.82 nM. Significance of the developed method in the field of agricultural and environmental domains was successfully investigated by monitoring MP and CBZ in water and soil samples, and the obtained results suggested the selectivity, stability, and reproducibility of the newly developed GO/g-C3N4/GCE electrode assembly.

A highly sensitive fluorescence probe for methyl parathion detection in vegetable and fruit samples based on N and S co-doped carbon dots

In this work, a highly sensitive fluorescence sensing system based on nitrogen and sulphur co-doped carbon dots (N,S-CDs) was for the first time developed for indirect measurement of methyl parathion (MP) with the aid of alkaline-induced hydrolysis. The N,S-CDs were prepared by using o-phenylenediamine and l-cysteine as precursors via hydrothermal heating. In a strong alkaline environment, MP was hydrolysed to p-NP which can suppress the fluorescence of N,S-CDs via a combination of IFE and dynamic interaction. The N,S-CDs exhibited high selectivity and sensitivity towards MP sensing, achieving a linear range of 0.01–15.0 μg/mL and a detection limit as low as 1.56 ng/mL. The proposed sensing platform was applied for MP detection in vegetable and fruit samples with satisfactory results. The recoveries were in a range of 96.4–104.4 %, and the relative standard deviations (RSDs) were less than 3.02 %.

A facile nonenzymatic electrochemical sensor based on copper oxide nanoparticles deposited on activated carbon for the highly sensitive detection of methyl parathion

A facile nonenzymatic electrochemical sensor based on copper oxide nanoparticles deposited on activated carbon for the highly sensitive detection of methyl parathion

Electrochemical sensing platform for the detection of methyl parathion applying highly biocompatible non-covalent functionalized phosphonium-based ionic liquid@MWCNTs hybrid to immobilize hemoglobin

A hydrophobic carboxyl functionalized phosphonium-based ionic liquid (IL) ((5-carboxypentyl) triphenylphosphonium bis (trifluoromethyl)sulfonyl) amide, TPP-HA[TFSI]) was synthesized through a simple hydrothermal approach. Based on the π-π and cation-π interactions with multi-wall carbon nanotubes (MWCNTs), a TPP-HA[TFSI]@MWCNTs hybrid was prepared to immobilize hemoglobin (Hb) to fabricate a simple and effective electrochemical sensing platform for the detection of methyl parathion (MP) in vegetables. Spectroscopic and electrochemical results show that TPP-HA[TFSI]@MWCNTs substrate synergistically provided a good biocompatible microenvironment for Hb, and the hydrophobicity of TPP-HA[TFSI] and the π-π interaction and hydrogen bonding between TPP-HA[TFSI]@MWCNTs, Hb and nafion (NF) were conducive to maintain the stability and integrity of the modified electrode interface. The TPP-HA[TFSI]@MWCNTs with large surface area and high conductivity promoted the exposure of the electroactive center of Hb and the direct electron transfer between Hb and the electrode, which effectively amplified the electrochemical signal and improved the sensitivity of MP detection. The constructed electrochemical sensing platform had a wider linear range (2–14 ng mL-1) and a lower detection limit (0.62 ng mL-1) for MP, and had acceptable repeatability, reproducibility, stability and anti-interference ability. This results indicated that the phosphonium-based ILs functionalized MWCNTs was an effective substrate for the immobilization of biological components, which have broad prospect in the construction of electrochemical sensing interfaces.

ZnO hollow spheres arrayed molecularly-printed-polymer based selective electrochemical sensor for methyl-parathion pesticide detection

A highly sensitive electrochemical-based detector was fabricated to selectively sense methyl-parathion (MP). A Glassy carbon electrode (GCE) was functionalized with zinc oxide (ZnO) hollow spheres (ZnOHS) and a molecularly imprinted polymer (MIP) to form the developed sensor. Cyclic voltammetry (CV) was performed to synthesize a molecularly imprinted polymeric film on the ZnOHS modified GCE (GCE/ZnOHS) by electropolymerization of functional monomer, l-arginine (L-Arg), and template molecule, MP. The differential pulse voltammetry (DPV) was utilized to evaluate the efficiency of the electrochemical detection of MP under optimal conditions by the proposed sensor. The developed sensor recorded a good performance for detecting MP in the linear range of 5 × 10 −9 to 0.1 × 10 −4 mol L −1 ( R 2 = 0 .985) with a detection limit (S/N = 3) of 0.5 × 10 −9 mol L −1 and sensitivity of 571 nA/ μ molL −1 cm −2 . This electrochemical sensing system effectively detects MP in real samples with satisfactory recoveries of 90.4%, 91.9%, 118%, and 96.3% for fresh green beans, strawberry, tomato, and cabbage, respectively. • Electrochemical biosensing platform helps to detect methyl parathion in environment. • ZnOHS arrayed MIP electrochemical sensor was developed for MP detection. • The developed GCE/ZnOHS/MIP sensor showed a sensitive and selective response to MP. • The proposed sensor showed good sensitivity, stability, and reproducibility.

Transparent and flexible AuNSs/PDMS-based SERS substrates for in-situ detection of pesticide residues

Herein, we developed a PDMS-based flexible SERS substrate modified with gold nanostars (AuNSs) for in-situ detection of pesticide residues on fruit surfaces. AuNSs with sharp branches were assembled on aminated PDMS membrane by chemical bonding effect. The AuNSs/PDMS substrate showed good signal uniformity, stability and sensitivity using the Raman signal molecule 4-MBA and the detection concentration of 4-MBA was as low as 10−8 mol/L. Then the AuNSs/PDMS substrate was used to detect methyl parathion (MP) standard solution. A good linear relationship between SERS intensity at 1342 cm−1 and MP concentration was established in the range of 4 μg/mL–100 μg/mL, and the limit of detection was down to 1.946 μg/mL. Moreover, the AuNSs/PDMS substrate was directly covered on the surface of MP contaminated apple, and the Raman laser was incident from the back of substrate to achieve in-situ detection of pesticide residues. The recovery ratio indicated that the fabricated SERS substrate was realized successfully in real sample detection. AuNSs/PDMS substrate eliminates the requirement for sample pre-processing steps before testing, which can be used as a method for rapid inspection of pesticide in agricultural products on site.

Combine etching-doping sedimentation strategy and carbonization to design double-deck petal-like NiO/CoO nanoporous carbon composite for methyl parathion detection

Designing efficient and rapid methods for detection of pesticide residue is one of the prerequisites to reduce its negative health influences. Herein, we constructed an electrochemical sensor for efficient detection of Methyl parathion (MP) using a double-deck petal-like NiO/CoO nanoporous carbon composite (Z-NiO/CoO@CC). The Z-NiO/CoO@CC was fabricated through etching-doping sedimentation strategy and carbonized conversion. The elaborate electrocatalyst not only created the structural advantages to offer more activities sites for the target analyte, but also had compositional virtues by combining the carbon nano-frame (originating from zeolitic imidazolate framework, ZIF-67) and bimetal oxides to enhance electrochemical performances. Besides, the electro-catalysis mechanism and detection performance of the prepared electrode were also detailly studied through different electrochemical techniques. Under optimized conditions, the prepared Z-NiO/CoO@CC showed favorable performance for MP detection with linear range from 10 ng/mL to 10 μg/mL, high sensitivity of 12.8 μA μM−1 cm−2 and low detection limit of 3.6 ng/mL (S/N = 3). Moreover, the practical feasibility of the Z-NiO/CoO@CC was also verified through monitoring MP in tap water and grape samples. This work has explored a novel method for construction of high-performance electrochemical MP sensors.

Non-Enzymatic Methyl Parathion Electrochemical Sensor Based on Hydroxyl Functionalized Ionic Liquid/Zeolitic Imidazolate Framework Composites Modified Glassy Carbon Electrode

A non-enzymatic methyl parathion (MP) electrochemical sensor was fabricated based on hydroxyl functionalized ionic liquid/zeolitic imidazolate framework composites modified glassy carbon electrode (IL-ZIF-67/GCE). Scanning electron microscopy (SEM) was used to study the surface morphologies of the modified electrodes. ZIF-67 could be well dispersed by hydroxyl functionalized ionic liquid. The structures of the modification materials were characterized using Fourier transform infrared spectroscopy (FT-IR). Square wave voltammetry (SWV) was employed to investigate the electrochemical behavior of MP. The factors affecting the performance of the proposed sensor were also optimized. The sensor makes full use of the high conductivity of hydroxyl functionalized IL and the superior electrocatalytic activity of ZIF-67, exhibiting excellent selectivity and stability. Under the optimal conditions, the IL-ZIF-67/GCE showed a good linear relationship for MP in the range of 1–20 ng l−1, and the detection limit was as low as 0.5 ng l−1 (S/N = 3). The sensor was applied for the detection of MP in river water samples, and the sample recoveries ranged from 96.6% to 101.2%.

Hierarchical nitrogen-doped holey graphene as sensitive electrochemical sensor for methyl parathion detection

Nitrogen-doped HG featuring a hierarchical macro- and nanoporous 3-D architecture with high pyrrolic-N content is a promising candidate for the construction of sensitive graphene-based electrochemical sensors for environmental and bioanalytical applications. • N-doped HG featuring a hierarchical macro- and nanoporous 3-D architecture for determination of MP was fabricated. • Pyrrolic-N in N-HG played a key role in enhanced electrocatalysis. • First principle calculations indicated that pyrrolic-N exhibited the strongest MP adsorption. • N-HG with a high pyrrolic-N content exhibited excellent sensing performance. • Ultra-low detection and excellent recovery in case of real samples were achieved. The determination of organophosphorus pesticide (OPS) residues is of great importance in reducing environmental pollution and ensuring food safety. A high-performance nitrogen-doped holey graphene (N-HG) electrochemical sensor for determination of methyl parathion (MP; one of the most commonly used OPS) based on a hierarchical macro- and nanoporous 3-D architecture has been successfully developed. The influence of various N-configurations on electron transfer kinetics and the sensing performance of the N-HG modified electrode was investigated systematically through combined practical and theoretical studies. Three N-bonding configurations were investigated in N-HG, namely, pyridinic N, pyrrolic N, and graphitic N. It was found that N-HG with a high pyrrolic-N content exhibited the largest electron transfer rate and the best sensing performance (ultralow detection limits: 3.5 pg·ml −1 ; wide linear range: 1 ng ml −1 –150 μg·ml −1 ), indicating that pyrrolic-N in the N-HG played a critical role in the electrochemical process and in enhanced electrocatalysis, as confirmed by first-principle calculations. Furthermore, the N-HG based sensor exhibited excellent selectivity and freedom from interference, good accuracy and satisfactory recoveries for real samples, confirming N-HG based electrochemical sensors have great scope for applications in environmental analysis and bio-sensing.

Graphene oxide@Ce-doped TiO2 nanoparticles as electrocatalyst materials for voltammetric detection of hazardous methyl parathion.

Asensitive voltammetric sensor has been developed for hazardous methyl parathion detection (MP) using graphene oxide@Ce-doped TiO2 nanoparticle (GO@Ce-doped TiO2 NP) electrocatalyst. The GO@Ce-doped TiO2 NPs were prepared through the sol-gel method and characterized by various physicochemical and electrochemical techniques. The GO@Ce-doped TiO2 NP-modified glassy carbon electrode (GCE) addresses excellent electrocatalytic activity towards MP detection for environmental safety and protection. The developed strategy of GO@Ce-doped TiO2 NPs at GCE surfaces for MP detection achieved excellent sensitivity (2.359μA μM-1 cm-2) and a low detection limit (LOD) 0.0016μM with a wide linear range (0.002 to 48.327μM). Moreover, the fabricated sensor shows high selectivity and long-term stability towards MP detection; this significant electrode further paves the way for real-time monitoring of environmental quantitative samples with satisfying recoveries.