Reduced graphene oxide decorated NiCo2(OH)6 nanoflowers for vortexed assisted dispersive µ-solid-phase extraction of organophosphorus pesticides in baby food cereal, rice and wheat flour.

Food safety is an important issue to protect humane health and improve the life quality. Hence, analysis of the possible contaminants in food samples is essential. A rapid and efficient vortexed-assisted dispersive µ-solid-phase extraction coupled with gas chromatography-mass spectrometry was proposed for simultaneous separation/preconcentration and determination of five commonly used organophosphorus pesticides. Reduced graphene oxide decorated NiCo2(OH)6 nanoflowers as a novel nanostructure was synthetized and introduced for separation of the target pesticides from the wheat flour, rice flour, and baby food cereal samples. The characterization of the nanoflowers was accomplished by SEM-EDX, XRD, and FT-IR techniques. The main factors including pH, the amount of nanoflower, the volume of sample solution, salt concentration (ionic strength), desorption conditions (i.e. desorption solvent type and volume, and desorption time) on the pesticides extraction efficiencies were inquired using matrixed match method. Applying the optimum conditions, the linearity of 0.100-500.000 µg kg-1, LODs and LOQs in the range of 0.03-0.04 µg kg-1 and 0.1 µg kg-1 for the studied food samples were obtained. The repeatability (intra-day precision (n = 5)) of ≤ 2.0 % and reproducibility (inter-day precision, days = 5, n = 3) of ≤3.1 % and were appraise at three concentration levels (10, 50 and 100 µg kg-1 of each analyte). High relative recoveries of 90.0-99.3 % ascertained high potential of the presented method for complex matrix analysis.

NiFe-LDH/nylon 6 composite electrospun on polypropylene membrane: A new extractive device development for porous membrane protected micro-solid-phase extraction of organophosphate pesticides from fresh fruit juice samples coupled with liquid chromatography tandem mass analysis.

A unique strategy for developing porous membrane protected micro-solid phase extraction has been provided. An electrospun composite was fabricated on the sheet of membrane. To this end, NiFe-layered double hydroxide/Nylon 6 composite nanofibers were coated on a polypropylene membrane sheet followed by folding into a pocket shape, which were then utilized as a novel extractive device to extract of organophosphorus pesticides from fresh fruit juice samples prior to liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The fabricated hybrid composites were successfully characterized. The effective parameters on extraction performance were investigated. LODs were 0.020-0.065 ng mL-1. Excellent linearity (R2≥0.996) was observed between 0.05 and 100.0 ng mL-1. RSDs% were in the range of 3.1-5.8% (intra-day, n = 3) and 2.6-5.5% (inter-day, n = 3×3). Satisfactory related recovery values within the acceptable range of 90.7-111.2% with RSDs% below 6.7% were achieved for the analysis of real samples.

A novel honeycomb-like 3D-printed device for rotating-disk sorptive extraction of organochlorine and organophosphorus pesticides from environmental water samples.

In this study, 3D-printing based on fused-deposition modeling (FDM) was employed as simple and cost-effective strategy to fabricate a novel format of rotating-disk sorptive devices. As proof-of-concept, twenty organochlorine and organophosphorus pesticides were determined in water samples through rotating-disk sorptive extraction (RDSE) using honeycomb-like 3D-printed disks followed by gas chromatography coupled to mass spectrometry (GC-MS). The devices that exhibited the best performance were comprised of polyamide + 15 % carbon fiber (PA + 15 % C) with the morphology being evaluated through X-ray microtomography. The optimized extraction conditions consisted of 120 min of extraction using 20 mL of sample at stirring speed of 1100 rpm. Additionally, liquid desorption using 800 µL of acetonitrile for 25 min at stirring speed of 1100 rpm provided the best response. Importantly, the methodology also exhibited high throughput since an extraction/desorption platform that permitted up to fifteen simultaneous extractions was employed. The method was validated, providing coefficients of determination higher than 0.9706 for all analytes; limits of detection (LODs) and limits of quantification (LOQs) ranged from 0.15 to 3.03 µg L-1 and from 0.5 to 10.0 µg L-1, respectively. Intraday precision ranged from 4.01 to 18.73 %, and interday precision varied from 4.83 to 20.00 %. Accuracy was examined through relative recoveries and ranged from 73.29 to 121.51 %. This method was successfully applied to analyze nine groundwater samples from monitoring wells of gas stations in São Paulo. Moreover, the greenness was assessed through AGREEprep metrics, and an overall score of 0.69 was obtained indicating that the method proposed can be considered sustainable.

Phoslactomycins Revisited: Polyketide Tetrahydrofurans and Lactones from an Australian Wasp Nest-Derived Streptomyces sp. CMB-MW079.

Molecular network analysis of Streptomyces sp. CMB-MW079 detected rare phosphorylated natural products. Miniaturized cultivation profiling (MATRIX) established optimal conditions for the production, isolation, and identification of the polyketide δ-lactone phoslactomycin E (1) and new ester homologues, phoslactomycins J and K (2 and 3), as well as unprecedented heterocyclic analogues, the tetrahydrofuran cyclolactomycins A-D (4-7) and γ-lactone isocyclolactomycins A-C (8-10). We propose a biogenetic relationship linking these cometabolites with the known lactomycins A-C which were tentatively identified as minor cometabolites.

Synthesis of metal-organic framework @molecularly imprinted polymer adsorbents for solid phase extraction of organophosphorus pesticides from agricultural products.

The novel core-shell structural zeolitic imidazolate framework-8 @molecularly imprinted polymers were successfully synthesized by surface imprinting technique and used as adsorbents for solid-phase extraction of organophosphorus pesticides. The obtained hybrid composites were characterized by scanning electron microscopy, transmission electron microscopy and Fourier-transform infrared, and their adsorbing and recognition performance were evaluated by binding experiments. The results showed that zeolitic imidazolate framework-8 @molecularly imprinted polymers presented a typically core-shell structure with molecularly imprinted shell (about 50 nm) homogeneously polymerized on the surface of zeolitic imidazolate framework-8 core, and exhibited specific recognition towards organophosphorus pesticides with fast adsorption capacity. The adsorption and desorption conditions including sample loading solvent, sample pH, washing and elution solvent were optimized. Under optimum conditions, the solid-phase extraction based on zeolitic imidazolate framework-8 @molecularly imprinted polymers combined with high liquid chromatography-tandem mass spectrometry method for determining organophosphorus pesticides was established and exhibited good linearity (R2 ≥ 0.9927) in the range of 1-200 µg/L. With spiked at three different concentration levels in agricultural products (cauliflower, radish, pear, muskmelon), the recoveries ranged from 82.5% to 123.0% with relative standard deviations lower than 8.24%. The developed method was sensitive, convenient and efficient. More importantly, this study could provide a promising strategy for designing new adsorbents with extremely fast mass transfer rate for other potential trace contaminants.

Facile synthesis of covalent organic frameworks functionalized with graphene hydrogel for effectively extracting organophosphorus pesticides from vegetables.

A novel covalent organic framework material (3DGA@COFs), for use as a solid-phase dispersion sorbent, has been synthesized for extracting organophosphorus pesticides (OPs) from vegetables. The prepared 3DGA@COFs material exhibited many advantageous features, including a large specific surface area (127.95 m2/g) and high pore volume (0.0344 cm3/g), which made it an ideal sorbent for sample pretreatment. The experimental conditions affecting extraction performance (adsorbent type, adsorbent amount, reaction time, pH, ionic concentration, and eluent) were optimized systematically. The extracted analytes were detected by HPLC-MS/MS. Under optimized conditions, the proposed method exhibited a wide linear range (0.5-100 µg/L) and low limits of detection (0.01-0.14 µg/L). The recoveries (75.40%-102.13%) satisfied the requirements for a precise detection method. The proposed method was successfully used for determining malathion, triazophos, quinalphos in lettuce, tomato and cucumber samples, thus indicating the potential of using 3DGA@COFs materials for pretreating vegetable samples.

Solvent-assisted dispersive liquid-solid phase extraction of organophosphorus pesticides using a polypyrrole thin film-coated porous composite magnetic sorbent prior to their determination with GC-MS/MS.

A porous composite magnetic sorbent was developed and used as a solid phase for the solvent-assisted preconcentration of organophosphorus pesticides. The hierarchical porous composite sorbent was composed of polypyrrole thin film coated on the surface of porous alginate beads with embedded magnetite nanoparticles. The pores in the alginate hydrogel beads were produced by carbon dioxide bubbles from the reaction of incorporated calcium carbonate with hydrochloric acid. The porous network was filled with dichloromethane to assist extraction. The fabricated porous composite sorbent was characterized and sorbent fabrication and extraction conditions were optimized to obtain the best extraction performance. The developed sorbent was coupled with GC-MS/MS to determine organophosphorus pesticides in fruit juices and vegetable. Under optimized condition, the developed method provided good linear range of 0.03-200 µg L-1 for dichlorvos, malathion, and fenthion, and 0.075-200 µg L-1 for mevinphos, dimethoate, and parathion methyl, respectively. Limits of detection were in the range 0.010 to 0.025 µg L-1. This method exhibited good relative recoveries in the range 84 to 99% and RSDs lower than 8%. The good stability of the sorbent enabled up to eight cycles of reuse.Graphical abstract.

Effective extraction of organophosphorus pesticides using sol-gel based coated stainless steel mesh as novel solid-phase extraction sorbent.

In this study, for the first time, stainless steel meshes coated with poly(ethylene glycol) and carbon nanotubes (PEG-CNT) by sol-gel technique were used as the adsorbent for solid-phase extraction. The coated stainless steel is loaded onto a cartridge and used to isolate and extract organophosphorus pesticides (OPPs) from water and fruit juice samples. Effective extraction parameters such as sample volume, desorption solvent, and desorption solvent volume were studied and investigated. Under optimal conditions, the linearity of the method was obtained in the range of 0.03 to 80 ng mL-1 and also the limits of detection (LODs) of the method were ranged from 0.01 to 0.03 ng mL-1. The repeatability of the method was evaluated at three concentration levels (0.1, 1, and 50 ng mL-1), and the relative standard deviation (RSD%) of the method was obtained in the range of 3.8 to 4.8%. Finally, the proposed method was used to analysis of OPPs in real water and fruit juice samples, with relative recovery in the range of 94.3 to 99.8%.

Quantification of Trace Organophosphorus Pesticides in Environmental Water via Enrichment by Magnetic-Zirconia Nanocomposites and Online Extractive Electrospray Ionization Mass Spectrometry.

A total of 15 representative organophosphorus pesticides (OPPs), a class of water pollutants causing serious global concerns, have been sensitively quantified by internal extractive electrospray ionization mass spectrometry (iEESI-MS) after enrichment with Fe3O4-ZrO2 innovatively synthesized in our lab by a one step coprecipitation method. For the premium enrichment, the amounts of Fe3O4-ZrO2, pH value, adsorption time, type and volume of desorption solvent, and shaking time of desorption were systematically optimized. Under optimized conditions, the proposed method provided low limits of detection (LODs) of 0.14-16.39 ng L-1 with relative standard deviations (RSDs) of less than 8.7%. A wide linear response range of about 4 orders of magnitude was achieved with linear coefficients (R2) of 0.9921-0.9999 for all the analytes tested. The present method also provided good recoveries (85.4-105.9%) with acceptable precision (RSDs < 7.2%) in spiked environmental water samples. Furthermore, multiple analytes including dimethoate, omethoate, etc. were simultaneously detected in a single sample run, which was accomplished within 1 min, resulting in significantly improved analytical throughput for quantitative analysis of bulk amounts of samples. The experimental results demonstrated that Fe3O4-ZrO2-iEESI-MS provided advantages, including high sensitivity, high speed, and reasonable selectivity for the detection of OPPs, showing potential applications in environmental water sample analysis and environmental science.

Analysis of organophosphorus and pyrethroid pesticides in organic and conventional vegetables using QuEChERS combined with dispersive liquid-liquid microextraction based on the solidification of floating organic droplet.

A simple, sensitive and environmentally-friendly method for determining organophosphorus and pyrethroid pesticides in vegetables was developed to better evaluate the risk of consuming them. The pesticides in vegetables were extracted, purified and concentrated by using the QuEChERS (quick, easy, cheap, effective, rugged and safe method) combined DLLME-SFO (dispersive liquid-liquid microextraction based on solidification of floating organic droplet) techniques. The key parameters were optimized through orthogonal array experimental design and statistical analysis. The linearity of the calibration curves was satisfied in matrix-matched standard solution with R2 ≥ 0.99. The limits of detection and limits of quantification were 0.3-1.5 and 0.9-4.7 µg/kg, respectively. The average recoveries of pesticides were 61.6-119.4% with relative standard deviations <16.1%. Furthermore, the method was applied successfully to analyse the pesticides in 15 pairs of organic and conventional vegetables. These results reflect the efficiency, reliability and robustness of the developed method.

Multifiber solid-phase microextraction using different molecularly imprinted coatings for simultaneous selective extraction and sensitive determination of organophosphorus pesticides.

Three types of molecularly imprinted solid-phase microextraction fibers were fabricated through sol-gel method using diazinon, parathion-methyl, and isocarbophos as templates, respectively, and assembled together to construct a multifiber for analysis of organophosphorus pesticides in complex matrices. The multifiber provided large extraction capacity and high imprinting factor up to 3.89. In contrast, the imprinting factor of a single fiber was around 1.6, and the multi-template imprinted coating showed no selectivity. The multifiber was applied to analyze pesticides in fruits and vegetables. The limits of detection, which ranged from 0.0052 to 0.23 µg/kg, were lower than those obtained by a single molecularly imprinted fiber, and much lower than those reported by other methods. The recoveries of five analytes in spiked apple, cucumber, Chinese cabbage, and cherry tomato samples were 75.1-123.2%. The study shows that the molecularly imprinted multifiber could achieve simultaneous selective extraction and sensitive determination of multiple targets in complex matrices for high-throughput analysis.

Synthesized carbon nanodots for simultaneous extraction of personal care products and organophosphorus pesticides in wastewater samples prior to LC-MS/MS determination.

A simple, rapid and efficient solid-phase extraction method based on synthesized carbon nanodots was developed for the preconcentration and extraction of personal care products and organophosphorus pesticides in environmental matrices. Factorial (screening) and central composite designs were employed for the optimization of experimental conditions that could potentially influence the percentage recoveries of the target analytes. The experimental variables, including sample pH, mass of adsorbent, eluent volume and sample volume, were examined. Under the optimized conditions, the developed method was validated, and acceptable analytical results obtained showed good performance. The method accuracy carried out at two spiking levels (10 and 100 µg L-1) in different sample matrices ranged between 63 and 120%. The method precision based on relative standard deviation (% RSD) was < 10%. The linear range studied had a determination coefficient of (R2 > 0.995). The limits of detection (LOD) and limit of quantification (LOQ) established varied between 0.015-0.125 and 0.05-0.415 µg L-1 ,respectively. The ensuing method was applied successfully in the determination of the five multi-class organic compounds under study, in influent and effluent wastewater matrices, sampled from a municipal wastewater treatment plant located in Pretoria, South Africa.

Dispersive Solid-Phase Extraction Using Microporous Sorbent UiO-66 Coupled to Gas Chromatography-Tandem Mass Spectrometry: A QuEChERS-Type Method for the Determination of Organophosphorus Pesticide Residues in Edible Vegetable Oils without Matrix Interference.

A QuEChERS-type method without matrix interference was designed and developed to determine organophosphorus pesticide residues in edible vegetable oils, based on dispersive solid-phase extraction with cleanup using UiO-66 as sorbent. Microporous UiO-66 directly and selectively adsorbed organophosphorus pesticides and excluded interfering compounds. Clean analytes were obtained by elution and analyzed using gas chromatography-tandem mass spectrometry. The dispersive solid-phase extraction conditions (amount of adsorbent, extraction time, desorption solvent volume, and elution time) were optimized. The limits of detection of the pesticides in vegetable oils were 0.16-1.56 ng/g. Under optimized conditions, the average pesticide recoveries were 81.1-113.5%. The intraday and interday relative standard deviations for analyte recovery were <8.2 and <13.9%, respectively. Thus, the method is reliable and could detect organophosphorus pesticide residues in edible vegetable oils. Furthermore, UiO-66 can be easily recycled and reused at least 10 times, reducing the cost of analysis.

Synthesis and characterization of a poly(p-phenylenediamine)-based electrospun nanofiber for the micro-solid-phase extraction of organophosphorus pesticides from drinking water and lemon and orange juice samples.

A new micro-solid-phase extraction sorbent was synthesized by electrospinning poly(p-phenylenediamine)/poly(vinyl alcohol) in the presence of cetyltrimethylammonium bromide. The modified nanofiber was prepared by removing the majority of the poly(vinyl alcohol) from the nanofiber blend by exposing it to the hot water. Scanning electron microscopy and surface analysis were performed to study the homogeneity and porosity of the electrospun nanofiber. In addition, Fourier transform infrared spectroscopy was applied for more characterization. The capability of the new nanofiber was explored by applying it in the extraction and preconcentration of organophosphorus pesticides from aqueous medium. After solvent desorption, the extracted analytes were analyzed by high-performance liquid chromatography with diode array detection. Under the optimum conditions, the relative standard deviation values at the concentration level of 50 ng/mL were in the range of 4.8-8.3%. The calibration curve showed linearity in the range of 0.5-500 ng/mL, and the limits of detection (S/N = 3) for the studied compounds were 0.15 ng/mL. By analyzing Tehran drinking water, lemon juice, sour lemon juice, orange juice and sour orange juice, the applicability of the presented method was investigated and the relative recoveries were in the range of 76-102%.

Production of Antigen-Binding Fragment against O,O-Diethyl Organophosphorus Pesticides and Molecular Dynamics Simulations of Antibody Recognition.

Immunoassay for pesticides is an emerging analytical method since it is rapid, efficient, sensitive, and inexpensive. In this study, a recombinant antigen-binding fragment (Fab) against a broad set of O,O-diethyl organophosphorus pesticides (DOPs) was produced and characterized. The κ chain and Fd fragment were amplified via PCR and inserted into the vector pComb3XSS and the soluble Fab on phagemid pComb3XSS was induced by isopropyl β-d-thiogalactoside in E. coli TOP 10F’. SDS-PAGE, Western blotting, and indirect competitive ELISA results indicated that Fab maintained the good characteristics of the parental mAb. To better understand antibody recognition, the three-dimensional (3D) model of Fab was built via homologous modeling and the interaction between Fab and DOPs was studied via molecular docking and dynamics simulations. The model clearly explained the interaction manner of Fab and DOPs, and showed that the Arg-L96 and Arg-H52 were mainly responsible for antibody binding. This work provided a foundation for further mutagenesis of Fab to improve its characteristics.

Determination of Organophosphorous Pesticides in Blood Using Microextraction in Packed Sorbent and Gas Chromatography-Tandem Mass Spectrometry.

The aim of our work was to develop a method for the determination of six organophosphorous pesticides (Ops) (azynphos-ethyl (AZP), diazinon (DZN), chlorpyrifos (CLP), chlorfenvinfos (CLF), parathion-ethyl (PRT) and quinalphos (QLP)) in whole blood using microextraction by packed sorbent (MEPS) and analysis by gas chromatography-tandem mass spectrometry (GC-MS/MS). The optimization of the MEPS procedure was performed using a design of experiments (DOE) approach, assessing different factors that significantly affected the extraction efficiency. Ultimately, the number of sample strokes, wash volume, percentage of 2-propanol in the wash solvent and the number of elution strokes were successfully optimized using a response surface methodology (RSM). The developed and optimized method was fully validated according to international guidelines. Linearity was established from 2.5 to 50 µg/mL for AZP and from 0.5 to 50 µg/mL for the remaining compounds, with coefficients of determination (R2) higher than 0.99 in all cases. The lower limit of quantification were 2.5 µg/mL (AZP) and 0.5 µg/mL (remaining compounds). Recoveries ranged from 61% to 77%. Intra- and inter-day precision and accuracy were considered adequate according to the guidelines. This is the first method employing MEPS as a sample preparation procedure for the analysis of these OPs in whole blood.

Magnetic core micelles as a nanosorbent for the efficient removal and recovery of three organophosphorus pesticides from fruit juice and environmental water samples.

Sodium dodecyl sulfate coated amino-functionalized magnetic iron oxide nanoparticles were used as an efficient adsorbent for rapid removal and preconcentration of three important organophosphorus pesticides, chlorpyrifos, diazinon and phosalone, by ultrasound-assisted dispersive magnetic solid-phase microextraction. Fabrication of amino-functionalized magnetic nanoparticles was certified by characteristic analyses, including Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and transmission electron microscopy. Affecting parameters on the removal efficiency were investigated and optimized through half-fractional factorial design and Doehlert design, respectively. The analysis of analytes was performed by high-performance liquid chromatography with ultraviolet detection. Under the optimum conditions, extraction recoveries for 20 ng/mL of organophosphorus pesticides were in the range of 84-97% with preconcentration factors in the range of 134-155. Replicating the experiment in above condition for five times gave the relative standard deviations <6%. The calibration curves showed high linearity in the range of 0.2-700 ng/mL and the limits of detection were in the range of 0.08-0.13 ng/mL. The proposed method was successfully applied for both removal and trace determination of these three organophosphorus pesticides in environmental water and fruit juice samples.

In situ ionic liquid dispersive liquid-liquid microextraction coupled to gas chromatography-mass spectrometry for the determination of organophosphorus pesticides.

Nine organophosphorus pesticides (OPPs) were determined in environmental waters from different origins using in situ ionic liquid dispersive liquid microextraction (IL-DLLME). This preconcentration technique was coupled to gas chromatography-mass spectrometry (GC-MS) using microvial insert thermal desorption, an approach that uses a thermal desorption injector as sample introduction system. The parameters affecting both the microextraction and sample injection steps were optimized. The proposed method showed good precision, with RSD values ranging from 4.1 to 9.7%, accuracy with recoveries in the 85-118% range, and sensitivity with DLs ranging from 5 to 16 ng L-1.

Zero valent Fe-reduced graphene oxide quantum dots as a novel magnetic dispersive solid phase microextraction sorbent for extraction of organophosphorus pesticides in real water and fruit juice samples prior to analysis by gas chromatography-mass spectrometry.

A selective and sensitive magnetic dispersive solid-phase microextraction (MDSPME) coupled with gas chromatography-mass spectrometry was developed for extraction and determination of organophosphorus pesticides (Sevin, Fenitrothion, Malathion, Parathion, and Diazinon) in fruit juice and real water samples. Zero valent Fe-reduced graphene oxide quantum dots (rGOQDs@ Fe) as a new and effective sorbent were prepared and applied for extraction of organophosphorus pesticides using MDSPME method. In order to study the performance of this new sorbent, the ability of rGOQDs@ Fe was compared with graphene oxide and magnetic graphene oxide nanocomposite by recovery experiments of the organophosphorus pesticides. Several affecting parameters in the microextraction procedure, including pH of donor phase, donor phase volume, stirring rate, extraction time, and desorption conditions such as the type and volume of solvents and desorption time were thoroughly investigated and optimized. Under the optimal conditions, the method showed a wide linear dynamic range with R-square between 0.9959 and 0.9991. The limit of detections, the intraday and interday relative standard deviations (n = 5) were less than 0.07 ngmL-1, 4.7, and 8.6%, respectively. The method was successfully applied for extraction and determination of organophosphorus pesticides in real water samples (well, river and tap water) and fruit juice samples (apple and grape juice). The obtained relative recoveries were in the range of 82.9%-113.2% with RSD percentages of less than 5.8% for all the real samples.

A highly stable acetylcholinesterase biosensor based on chitosan-TiO2-graphene nanocomposites for detection of organophosphate pesticides.

A highly stable electrochemical acetylcholinesterase (AChE) biosensor for detection of organophosphorus pesticides (OPs) was developed simply by adsorption of AChE on chitosan (CS), TiO2 sol-gel, and reduced graphene oxide (rGO) based multi-layered immobilization matrix (denoted as CS@TiO2-CS/rGO). The biosensor fabrication conditions were optimized, and the fabrication process was probed and confirmed by scanning electron microscopy and electrochemical techniques. The matrix has a mesoporous nanostructure. Incorporation of CS and electrodeposition of a CS layer into/on the TiO2 sol-gel makes the gel become mechanically strong. The catalytic activity of the AChE immobilized CS@TiO2-CS/rGO/glassy carbon electrode to acetylthiocholine is significantly higher than those missing any one of the component in the matrix. The detection linear range of the biosensor to dichlorvos, a model OP compound, is from 0.036µM (7.9 ppb) to 22.6µM, with a limit of detection of 29nM (6.4 ppb) and a total detection time of about 25min. The biosensor is very reproducibly and stable both in detection and in storage, and can accurately detect the dichlorvos levels in cabbage juice samples, providing an efficient platform for immobilization of AChE, and a promisingly applicable OPs biosensor with high reliability, simplicity, and rapidness.