Pesticides Methyl Parathion Research Articles

Performance evaluation of Zr(CUR)/NiCo2S4/CuCo2S4 and Zr(CUR)/CuCo2S4/Ag2S composites for photocatalytic degradation of the methyl parathion pesticide using a spiral-shaped photocatalytic reactor.

Zr(CUR)/NiCo2S4/CuCo2S4 and Zr(CUR)/CuCo2S4/Ag2S ternary composites were synthesized as efficient photocatalysts, and well characterized through XRD, FTIR, DRS, FE-SEM, EDS, and EDS mapping techniques. The potential of a spiral-shaped photocatalytic reactor was evaluated for degradation of the methyl parathion (MP) pesticide using synthesized photocatalysts under visible light irradiation. Computational fluid dynamics (CFD) was applied for analysis of the hydrodynamics behaviour and mass transport occurring inside the reactor. The experiments were performed based on a developed CCD-RSM model, while the desirability function (DF) was used for optimization of the process. Findings showed that the highest MP degradation percentage was 98.70% at optimal operating values including 20 mg L-1, 0.60 g L-1, 8 and 40 min for MP concentration, catalyst dosage, pH, and reaction time, respectively. This study clearly demonstrated that high degradation efficiency can be achieved using a spiral-shaped photocatalytic reactor rather than a traditional annular reactor at same conditions. The increase in reaction rate is related to the higher average turbulence kinetic energy in the spiral-shaped reactor over the traditional reactor, which results in the increased diffusivity and improves the mass and momentum transfer.

Effective removal of different species of organophosphorus pesticides (acephate, omthosate, and methyl parathion) using chitosan/Zeolite-A as multifunctional adsorbent

Chitosan/zeolite-A composite (CS/ZA) was synthesized and characterized as a multifunctional, eco-friendly, and enhanced adsorbent for three species of organophosphorus pesticides (acephate (AC), omthosate (OM), and methyl parathion (MP)). The CS/ZA composite achieved maximum capacities of 650.7 mg/g, 506.5 mg/g, and 560.8 mg/g for AC, OM, and MP, respectively. The kinetic and equilibrium inspection validate Pseudo-first order and Langmuir properties for the uptake of the pesticide by CS/ZA. Moreover, the thermodynamic parameters declared the nature of these reactions as spontaneous, favorable, and exothermic processes. The values of Gaussian energy, enthalpy, and free energy suggested a complex uptake mechanism involving chemical and physical reactions for the assessed pesticides. The CS/ZA composite showed promising affinities for the AC, OM, and MP pesticides even in the existence of other inorganic anions or metal ions. The adsorption properties of CS/ZA as a fixed bed (6 cm) in column systems achieved removal percentages of 78% (AC), 57.6% (OM), and 74.3% (MP) considering the selected flow rate (5 mL/min), concentration (25 mg/L), and pH (pH 8). The CS/ZA displayed considerable stability and recyclability during the removal of the three pesticides. • Chitosan/zeolite-A was used in the adsorption of organophosphorous pesticides. • The q max of acephate, omthosate, and methyl parathion are 650, 506, and 560 mg/g. • The uptake behavior of both ions follow Langmuir and Pseudo-First order models. • The uptake of the ions occurred by physical exothermic and spontaneous reactions. • The column tests showed promising removal of the pesticides by the composite bed.

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.

Engineering of highly Brachychiton populneus shells@polyaniline bio-sorbent for efficient removal of pesticides from wastewater: Optimization using BBD-RSM approach

New biocomposite based on polyaniline and Brachychiton populneus shells (BP@PANI) was successfully synthesized through in situ chemical polymerization. The prepared composite was characterized using different analytical techniques such as scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR) and Brunauer-Emmett-Teller (BET) analysis. The BP@PANI material was effectively used as an adsorbent to remove thiabendazole (TBZ) and methyl parathion (MP) pesticides from wastewater. The kinetic and equilibrium results indicated that the adsorption process followed the pseudo-second-order model and the Langmuir isotherm. The optimum adsorption amounts were 255.39 and 78.59 mg.g−1 for TBZ and MP, respectively. The biosorption mechanism of both pesticides was evaluated and assigned to electrostatic interactions, pi-pi interactions and hydrogen bonding. The desorption study proved the excellent recycling of BP@PANI biosorbent. Moreover, the biosorption process was optimized by the response surface methodology combined with the Box Behnken design (RSM-BBD). The optimal parameters were found to be : Dose = 0.88 g.L−1, Ci = 5 mg.L−1 and Time = 100 min for TBZ and Dose = 1 g.L−1, Ci = 5 mg.L−1 and Time = 120 min for MP. The predicted elimination efficiency was determined to be 85% for TBZ and 84% for MP. The experimental data obtained were in good agreement with that predicted by the model, which indicates the importance of the RSM approach in terms of modeling and optimization.

Effect of ozone application on the removal of pesticides from grapes and green bell peppers and changes in their nutraceutical quality

The present study evaluates the efficacy of ozonated water for the removal of pesticide residues in grapes and green bell peppers. Fruit fortified with pesticides (azoxystrobin, chlorothalonil, chlorpyrifos, cypermethrin, hexaconazole and methyl parathion) were subjected to 15 and 30 min aqueous ozone treatment. GC analysis of ozonated fruits showed a 48.67% to 96.95% decrease in pesticide residues of different pesticides. Methyl paraoxon, a toxic degradation product of methyl parathion, was detected in the ozonated water sample. To assess the effect of ozonation on the nutraceutical quality of fruits, the concentrations of eleven polyphenols and ascorbic acid were analyzed. The individual polyphenols showed different trend in 15 and 30 min treatment. Overall, there was an increase in the levels of all the polyphenols in grapes after 30 min ozonation treatment. In peppers, there was a net increase in quercetin, quercetin-3-O-glucoside, rutin and kaempferol in 30 min while other polyphenols were decreased. The ascorbic acid content of both the fruits was decreased by more than 70% upon ozonation. Thus, ozonation treatment was effective in pesticide removal. However, it changed the nutraceutical quality of grapes and green bell peppers.

Insight into carbohydrate polymers (chitosan and 2- hydroxyethyl methacrylate/methyl methacrylate) intercalated bentonite-based nanocomposites as multifunctional and environmental adsorbents for methyl parathion pesticide

Two-hybrid products of bentonite intercalated carbohydrate polymers (chitosan (BE.P.CH) and 2- hydroxyethyl methacrylate/methyl methacrylate copolymer (BE/P.HEMA/MMA)) were synthesized as enhanced adsorbents for methyl parathion pesticide (MPP). The intercalation processes induced the affinity and the capacity of bentonite achieving the best value at pH 8. The maximum MPP adsorption capacities of BE (287.3 mg/g), BE/P.CH (634.5 mg/g), and BE/P.HEMA-MMA (868.5 mg/g) obtained after 300 min, 240 min, and 360 min, respectively. The kinetic properties of BE follow the Pseudo-second order behavior (R2 = 0.93) while BE/P.CH and BE/P.HEMA-MMA are of Pseudo-First order behavior (R2 > 0.92). Based on the equilibrium studies, the three products are of Freundlich isotherm behavior (R2 > 0.9) and the uptake is of multilayer forms on heterogeneous surfaces. The Gaussian energies (>8 KJ/mol), Gibbs free energies (>20 to <40 KJ/mol), and enthalpies (>40 to <80 KJ/mol) give an indication about adsorption mechanism involved chemical and physical reactions. The thermodynamics of MPP uptake reactions by the three products are of endothermic and spontaneous behaviors. The MPP uptake in the presence of NH+4, PO4−3, Mn+2, and Pb+2 competitive ions reflects enhancement in the affinity of BE after the integration between it and the selected polymers.

Carbon Catabolite Repression of Methyl Parathion Degradation in a Bacterial Isolate Characterized as a Cupriavidus sp. LMGR1

Among the mixture of carbon compounds, bacteria have the ability to select energetically efficient substrate as a preferred carbon source. This specific behavior often limits the use of pollutants as a secondary carbon source by bacteria grown with preferred carbon source and the pollutants. Therefore, to develop an efficient bioremediation technology for removal/degradation of organophosphorus pesticide methyl parathion (MP) from agricultural soils, a soil bacterial strain (LMGR1) capable of degrading MP and p-nitrophenol was isolated and identified as a Cupriavidus oxalaticus based on biochemical (carbon utilization pattern) and molecular analysis (16S rRNA gene sequence), but the phylogenetic analysis revealed a distinct position, and the name was designated as Cupriavidus sp. LMGR1. The effect of preferred carbon source on degradation was also investigated. The bacterium assimilated the pesticide as a sole source of carbon and consumes about 100 mg L−1 of MP within 6 to 7 h of incubation. Furthermore, the methyl parathion hydrolase (MPH) enzyme (localized in the periplasm of bacterium) activity was induced by the carbon deficiency instead of substrate. Determination of kinetic parameters, i.e., Vmax and Km for MPH enzyme in the extracted periplasmic protein indicated significant higher affinity towards the substrate. The reduced MPH activity in the bacterium grown in presence of preferred carbon source indicated the role of carbon catabolite repression in regulation of pesticide degradation. Thus, the bacterium has prodigious capability to be used as a bioremediation agent, but the availability of preferred carbon source may affect its potential in field application.

Easy-to-use and reliable absorbance-based MPH-GST biosensor for the detection of methyl parathion pesticide

Due to high contamination of organophosphate (OP) insecticides in agricultural products and the environment, efficient and convenient devices for their monitoring are necessary. Here, a simple, inexpensive, efficient, and easy-to-use absorbance-based biosensor was fabricated utilizing recombinant methyl parathion hydrolase fused with glutathione-S-transferase (MPH-GST), covalently immobilized onto a chitosan film-coated polystyrene microplate, for the detection of methyl parathion (MP) as a representative of OPs. Having been connected to the transducer system designed to work through an Arduino microcontroller, the biosensor could detect MP as efficiently as the conventional methods, with the detection limit of 0.1 μM, the lowest value ever reported for this method. It was stable at 25 °C for 30 days, could function 100 rounds repetitively, and yielded high recovery with real samples. Hence, this simply designed MPH-GST biosensor could be an easy and inexpensive alternative for efficient OP screening at site to help control its contamination.

Quantitative Analysis of Methyl-Parathion Pesticide in Presence of Enzyme Substrate Using Tapered Fiber Optic Biosensor

Application of a non-adiabatic tapered fiber optic biosensor for real-time, label-free detection of methyl-parathion pesticide (MPT) in presence of acetylthiocholine iodide (ATCh) is presented. The limit of detection of MPT in the presence of 1 mM ATCh as an enzyme substrate is found to be as low as $23\times 10\,\,^{-{9}}$ M (S/N=3). The proposed sensor shows a dynamic range of 2.3 nm and a working range of 0.12 to $31~\mu \text{M}$ . More importantly, it has the capability of quantifying the binding constants of MPT to the enzyme acetylcholinesterase (AChE) by performing just a single experiment. This can be done through the kinetic analysis of the analyte-enzyme reaction in the presence/absence of ATCh. The results show an association rate of $3.835\times 10\,\,^{{4}}\,\,\text{M}^{-{1}}\text{s}^{-{1}}$ and a dissociation rate of 0.2745 s−1 for MPT-AChE binding in presence of ATCh which lead to a value of $1.4\times 10\,\,^{{5}}\,\,\text{M}^{-{1}}$ for equilibrium binding constant and $7.16~\mu \text{M}$ for dissociation constant. Detection of MPT in the tap and river water at low levels has been achieved and the sensor specificity examined against different substances. Based on the obtained results, our biosensor can pave the way toward low-cost, real-time, label-free, and quantitative determination of organophosphate pesticides in real samples.

Effect of magnetite transformations on degradation efficiency of cerium dioxide-magnetite composite

Present investigations are focused on synthesis of magnetite/cerium dioxide reactive sorbents in various weight ratios of components and their characterization of chemical and magnetic properties. The morphology and changes in magnetic transformations in dependence on composition are followed by electron microscopy, X-ray diffraction, Mössbauer spectroscopy and magnetic measurements at room and low temperatures. Degradation efficiency is evaluated from a decomposition of the organophosphorus pesticide parathion methyl using prepared reactive sorbents. The experimental results reveal that the degradation efficiency, expressed by rate constant (mol/h) in dependence on amount of cerium dioxide content (vol.%), is independent on kind of iron oxide but increases with cerium dioxide content. On the contrary, saturation and remanent magnetizations are highly sensitive to relative ratio of iron oxides; magnetite, maghemite and hematite, originating from the initial magnetite transformations in dependence on sample composition.

Fabrication of Pt-Pd@ITO grown heterogeneous nanocatalyst as efficient remediator for toxic methyl parathion in aqueous media.

In this study, nano-sized ITO supported Pt-Pd bimetallic catalyst was synthesized for the degradation of methyl parathion pesticide, a common extremely toxic contaminant in aqueous solution. On the characterization with different techniques, a beautiful scenario of honeycomb architecture composed of ultra-small nanoneedles or fine hairs was found. Average size of nanocatalyst also confirmed which was in the range of 3-5nm. High percent degradation (94%) was obtained in 30s using 1.5 × 10- 1mg of synthesized nanocatalyst, 0.5mM NaBH4, and 110W microwave radiations power. Recyclability of nanocatalyst was efficient till 4th cycle observed during study of reusability. The supported Pt-Pd bimetallic nanocatalyst on ITO displayed many advantages over conventional methods for degradation of methyl parathion pesticide, such as high percent degradation, short reaction time, small amount of nanocatalyst, and multitime reusability. Graphical abstract Schematic illustration of reaction for degradation of methyl parathion.

Effective oxidation of methyl parathion pesticide in water over recycled glass based-MCM-41 decorated by green Co3O4 nanoparticles

Pieces of glass as solid wastes were recycled in the synthesis of highly order MCM-41 that decorated by green fabricated Co3O4 nanoparticles using the green extract of green tea leaves forming novel green nano-composite. The synthetic Co3O4/MCM-41 exhibit high surface area, low bandgap energy (1.63 eV), and typical spherical morphology decorated by Co3O4 nanoparticles. The composite was evaluated as green photocatalyst in effective oxidation of methyl parathion pesticide in the presence of a visible light source. The degradation results revealed complete removal of 50 mg/L and 100 mg/L after 60 min and 90 min, respectively using 0.25 of the catalyst at pH 8. The detection of the TOC in the treated methyl parathion solution gives strong indications about the formation of organic intermediate compounds during the oxidation steps. The main detected intermediate compound are C6H5OH(NO2), C6H5OH, (CH3O)3P(S), C6H4(OH)2, C6H3(OH)3, C6H4(NH2)OP(O)(OCH3)2, (CH3O)2P(O)OH, (CH2)2C(OH)OH(CHO)OC(O), and HO2C(CH2)2C(O)CHO. The detected intermediate compounds converted into SO42−, PO43−, NO3−, and CO2 under the extensive photocatalytic of them over Co3O4/MCM-41. The oxidizing species trapping test verified the controlling of the methyl parathion degradation pathway by the hydroxyl radicals. Finally, the composite showed significant reusability properties and applied five times in the oxidation of methyl parathion with considerable degradation percentages.

Chemically-Activated Biochar from Ricinus communis L. Cake and Their Potential Applications for the Voltammetric Assessment of Some Relevant Environmental Pollutants

Biochar is a rich-carbon material highly functionalized, which allows the use as electrodes modifier for preconcentration and voltammetric determination of several species. This work describes a castor cake biochar production and chemical activation with different reaction conditions using HNO3 and/or H2O2. Biochar samples were characterized using scanning electron microscopy, energy dispersive spectroscopy, thermogravimetric analysis, Fourier-transform infrared spectroscopy, Raman and zeta potential. Carbon paste modified electrodes (CPME) have been constructed using different biochar samples to evaluate the adsorptive capacity for the spontaneous preconcentration and voltammetric determination of Pb2+, Cd2+, Cu2+ and Ni2+ ions, paraquat and methyl parathion pesticides. The activation treatments promoted modifications in the elemental, morphological and structural biochar characteristics. Activated biochar CPMEs showed increase in the current signal around 15 and 2.5 times higher than unmodified and precursor biochar electrode, respectively. N2 sample (HNO3, 60 °C for 3.0 h) presented the better response signals for all compounds. This was attributed to the more effective surface oxidation, promoting a high porosity, acid character and amount of acid functional groups. Besides that, this greater analytical response allows the CPME-N2 application as a passive sampler for the voltammetric determination of inorganic and organic contaminants for environmental management in aqueous matrices.

Room-temperature synthesis of nanoceria for degradation of organophosphate pesticides and its regeneration and reuse.

A simple low-temperature water-based and one-pot synthesis was developed for the preparation of nanocrystalline CeO2 that was used for degradation of the toxic organophosphate pesticide parathion methyl. By changing the reaction temperature in the range from 5 °C to 95 °C, several properties (i.e., crystallinity, grain size and surface area) of nanoceria can be easily controlled. The catalytic decomposition of parathion methyl to its degradation product 4-nitrophenol was highly dependent on the CeO2 preparation temperature. It was demonstrated that at low temperature (i.e. 5 °C), CeO2 with very small crystallites (<2 nm) and high surface area can be obtained. For practical use, it was demonstrated that highly crystalline CeO2 can be prepared at room-temperature (30 °C) in at least 100 g batches. It was shown that precipitated nanoceria had high thermal stability and its post-synthesis annealing up to 400 °C did not significantly alter the material properties and hence the catalytic activity. Furthermore, as shown by the reusability tests, the sorbent can be reactivated by simply washing with water which demonstrated its durability.

Chemical Wet Oxidation of Carbon Nanotubes for Electrochemical Determination of Methyl Parathion

Surface properties of carbon nanotubes in electrochemical sensors can be dramatically altered depending on chemical groups and structural defects present on the surface. The effect of oxidation on structural integrity of multiwalled carbon nanotubes through acidic (nitric/sulfuric acids) and basic (sodium hydroxide) agents has been studied. Chemical modifications of carbon nanotubes structures were evaluated by Raman, Fourier transform infrared spectroscopy and transmission electronic microscopy. Furthermore, these materials were used to construct sensors for electrochemical determination of pesticide methyl parathion (MP). Under optimized conditions, a calibration curve was obtained for MP determination employing a glassy carbon electrode modified with acidic treated and basic treated carbon nanotubes which showed a linear response ranging from 1.0 × 10–7 to 3.4 × 10–5 M with limits of detection of 3.3 × 10–8 and 3.5 ×10–8 M, respectively. Analytical performance of the electrodes showed similar voltammetric behavior providing good sensitivity for the determination of methyl parathion.

3D Sphere-like Nickel Tungstate Catalyst for Destroying of Organophosphate Pesticide Methyl Parathion

Recently, the appearance of pesticide residues into the environment poses serious risks to the living organisms. In this view, we explored a novel and superior photocatalyst based on nanostructured sphere-like nickel tungstate (NiWO4 NSs) for the degradation of organophosphate pesticide methyl parathion (MP) under visible light irradiation, for the first time. The NiWO4 NSs were tailored through simple precipitation technique and confirmed by several spectroscopic techniques. Fascinatingly, the NiWO4 NSs portrayed superior photodegradation performances towards MP degradation with superior stability.

Morphological influence of ZnO nanostructures and their Cu loaded composites for effective photodegradation of methyl parathion

This report signifies the synthesis of ZnO nanorods, cotton ball like structures, nanospheres and their Cu loaded counterparts for effective photocatalytic degradation of methyl parathion pesticide under UV light. Pesticides accumulation in ecosystem becomes major problem which affects health. Zinc oxide is a promising photocatalyst for degradation of pesticides and dyes because of its higher stability, low cost and non-toxic nature. Herein, the synthesized catalysts were characterised by diffused reflectance spectroscopy, X-ray diffraction, scanning electron microscopy techniques and transmission electron microscopy. ZnO nanorods (ZNR) proved to be better catalyst as compare to other synthesized nanostructures because of its elongated morphology. ZNR were nearly 1.4 times more efficient than ZnO cotton ball like structures. Moreover, photocatalytic activity was also enhanced by Cu loading due to low recombination rate of excitons. Cu loaded ZNR were found to degrade whole compound up to 99% in just 80 min whereas bare ZNR took 3 h under similar conditions. Thus, efficiency of Cu-ZNR had been increased nearly 6 folds as that of bare ZNR.

Reduced graphene oxide nanosheets modified with nickel disulfide and curcumin nanoparticles for non-enzymatic electrochemical sensing of methyl parathion and 4-nitrophenol.

A method was designed for simultaneous voltammetric determination of methyl parathion pesticide (MP) and 4-nitrophenol (4-NP). Curcumin nanoparticles were deposited on reduced graphene oxide nanosheets that were modified with nickel disulfide. The material was placed on a screen-printed carbon electrode and then displayed high electrocatalytic activities toward MP and 4-NP, with a peak potential near -0.9 and - 0.7V (vs. pseudo Ag/AgCl), respectively. Figures of merit include (a) good electrochemical sensitivities (7.165 and 6.252μA·μM-1·cm-2), (b) wide linear ranges (from 0.25 to 80μM), (c) low limits of detection (8.7 and 6.9nM at S/N = 3) for MP and 4-NP, respectively, and (d) good selectivity, repeatability, reproducibility, and storage stability. The method was applied in the determination of MP and 4-NP in tomato and apple juices and spiked river water. Graphical abstract A novel electrocatalysis platform based on reduced graphene oxide-nickel disulfide nanosheets decorated with curcumin nanoparticles for simultaneous quantification of methyl parathion and 4-nitrophenol in various vegetarian juices and water samples.

Large-area cost-effective lithography-free infrared metasurface absorbers for molecular detection

The implementation of metasurface absorbers for advanced sensing applications in the infrared spectral range is gaining prominence. Nevertheless, scale-up is challenging because their subwavelength features require complex fabrication techniques. Here, we present centimeter-sized nanostructured metasurface absorbers, prepared using the nanoporous anodic aluminum oxide template method, which exhibit a high and polarization-insensitive absorptivity at near-infrared wavelengths. Their sensing potential as surface-enhanced Raman spectroscopy substrates is demonstrated by analyzing Raman spectra of methyl parathion pesticides at concentrations as low as 100 ppb. Our results offer a stable, cost-effective, scalable, and uniform solution for metasurface-based molecular detection applications with a high sensitivity.

Rapid detection of multiple organophosphorus pesticides (triazophos and parathion-methyl) residues in peach by SERS based on core-shell bimetallic Au@Ag NPs

ABSTRACTIn this study, a surface-enhanced Raman scattering (SERS) approach based on silver-coated gold nanoparticles (Au@Ag NPs) was established for rapid detection of multiple organophosphorus pesticides (triazophos and methyl-parathion) in peach fruit. The Raman enhancement of Au@Ag NPs for detecting organophosphorus pesticides was stronger than those of single Ag and Au NPs. It was revealed that core size of Au NPs was a critical parameter affecting the enhancement of Raman signals by joining two plasma resonance absorptions. The Au@Ag NPs with 26 nm Au core size and 6 nm Ag shell thickness showed significant Raman enhancement, especially by the creation of hot spots through NPs aggregation induced by connection between Au@Ag NPs and target molecules. The detection limits of triazophos and methyl-parathion in peach were 0.001 mg/kg. Good recovery (93.36 to 123.6 %) and high selectivity of the SERS activity allowed excellent precision for the detection of the triazophos and methyl-parathion in peach. Compared to earlier studies, the current approach was rapid, inexpensive and simple without lengthy sample pre-treatment. This study revealed that the proposed method could be employed for the analysis of trace contaminants such as triazophos and methyl-parathion in many food matrices.