Organophosphorus Pesticides Research Articles

Covalent adduct formation of histone with organophosphorus pesticides in vitro

It is established that organophosphorus pesticide (OPP) toxicity results from modification of amino acids in active sites of target proteins. OPPs can also modify unrelated target proteins such as histones and such covalent histone modifications can alter DNA-binding properties and lead to aberrant gene expression. In the present study, we report on non-enzymatic covalent modifications of calf thymus histones adducted to selected OPPs and organophosphate flame retardants (OPFRs) in vitro using a bottom-up proteomics method approach. Histones were not found to form detectable adducts with the two tested OPFRs but were avidly modified by a few of the seven OPPs that were tested in vitro. Dimethyl phosphate (or diethyl phosphate) adducts were identified on Tyr, Lys and Ser residues. Most of the dialkyl phosphate adducts were identified on Tyr residues. Methyl and ethyl modified histones were also detected. Eleven amino residues in histones showed non-enzymatic covalent methylation by exposure of dichlorvos and malathion. Our bottom-up proteomics approach showing histone-OPP adduct formation warrants future studies on the underlying mechanism of chronic illness from exposure to OPPs.

Construction of phosphatase-like COF-OMe@Valine-CeO2 nanozymes for ultrasensitive electrochemical detection of organophosphorus pesticides

Construction of highly-active artificial nanozymes for pesticides detection has great significance of human health and ecological systems. Herein, we have successfully designed a two-step approach to synthesize the TAPB-DMTP-COF (hereafter denoted as COF-OMe, TAPB, 1,3,5-tris(4-aminophenyl)benzene; DMTP, 2,5-dimethoxyterephaldehyde; COF, covalent organic framework)@Valine integrated cerium oxide nanozymes (COF-OMe@Valine-CeO2) with phosphatase-like activities, which can cleave phosphate bonds (PO) of organophosphorus pesticides (OPs) for the formation of electroactive p-nitrophenol (p-NP). In detail, the Ce (IV)/Ce (III) species serve as the active sites to polarize and hydrolyze PO bond in OPs, and the excellent adsorption performance of porous COF-OMe toward OPs could promote the hydrolysis process of PO. Moreover, the efficient charge transfer at the covalent interface of COF-OMe@Valine-CeO2 also contributed to this excellent catalytic process. By virtue of those advantages, the COF-OMe@Valine-CeO2 electrochemical platform was successfully applied in methyl-paraoxon (MP) detection. The resulting electrochemical sensors displayed high sensitivity, a wide linear response range of 0.034–76 μmol/L, and low detection limits of 0.011 μmol/L for MP. The research not only provides a preparation method for COF with excellent nanozyme activity, but broadens some new insights for the design of highly efficient nanozymes for on-time detection for OPs.

Superior oxidase-mimetic activity of FeCo-NC dual-atom nanozyme for smartphone-based visually colorimetric assay of organophosphorus pesticides.

A colorimetric analysis platformhas been successfully developedbased on FeCo-NC dual-atom nanozyme (FeCo-NC DAzyme) for the detection of organophosphorus pesticides (OPPs). The FeCo-NC DAzyme exhibited exceptional oxidase-like activity (OXD), enabling the catalysis of colorless TMB to form blue oxidized TMB (oxTMB) without the need for H2O2 involvement. By combining acid phosphatase (ACP) hydrolase with FeCo-NC DAzyme, a "FeCo-NC DAzyme + TMB + ACP + SAP" colorimetric system was constructed, which facilitated the rapid detection of malathion. Thechromogenic system was appliedto detect malathion using a smartphone-based app and an auxiliary imaging interferogram device for colorimetric measurements, which have a linear range of 0.05-4.0 µM and a limit of detection (LOD) as low as 15 nM in real samples, comparable to UV-Vis and HPLC-DAD detection methods. Overall, these findings present a novel approach for convenient, rapid, and on-site monitoring of OPPs.

Time-series variation in the locomotor behavior and vocal traits of Japanese medaka (Oryzias latipes) acutely exposed to organophosphorus pesticide chlorpyrifos

Organophosphorus pesticides (OPs), such as chlorpyrifos (CPF), are the most commonly used pesticides worldwide. Considering that OPs will eventually enter aquatic ecosystems due to runoff from agricultural lands, accidental leakage, and other unforeseen emergencies, monitoring water pollution of those substances is crucial for environmental protection and public health. In this study, Japanese medaka (Oryzias latipes) were exposed to CPF (0.03, 0.06, and 0.12 mg/L) for 6 h, and the time-series variations in their locomotor behavior and vocal traits were investigated. Compared with that measured before exposure, significantly changed locomotor behavior and vocal traits in Japanese medaka exposed to CPF could be observed at 4 h after exposure and thereafter, and the pattern of behavioral changes depends on the CPF concentrations. Exposure to CPF also changed the frequency-sound pressure level curve of Japanese medaka at 6 h after exposure, especially at 0.12 mg/L. Moreover, CPF exposure could significantly inhibit the acetylcholinesterase (AChE) activity in the brains and eyes of medaka, which exhibited significant correlations with the variation of locomotor behavioral and vocal traits. Considering that inhibiting the AChE activity is the primary mechanism underlying the neurobehavioral toxicity of all OPs, our finding suggested that simultaneously monitoring changes in the locomotor behavioral and vocal traits has a high potential to reflect the pollution of organophosphorus substances.

N-DOPED POROUS CARBON DERIVED FROM A DEEP EUTECTIC SOLVENT AND ITS APPLICATION IN SOLID-PHASE EXTRACTION OF PROFENOFOS FROM FRUITS

Porous N-doped carbon materials with glucose and urea derived from a deep eutectic solvent, and their performance in determining pesticides were investigated. The carbon materials were characterized with nitrogen absorption, transmission electron microscopy, X-ray photoelectron spectroscopy, and the results showed that they had high specific surface areas, pore volumes and rich functional groups. Under optimized conditions, this method showed a good linearity (0.2–2.0 µg/mL) and high sensitivity (detection limit of 0.023 µg/mL, S/N = 3). The proposed method was successfully applied in an analysis of a fruit sample with recoveries ranging from 97.2 % to 103.3 %, and good reproducibility was achieved. This work revealed great potentials of a porous N-doped carbon material used as an excellent sorbent material in analyzing organophosphorus pesticides.

Biotransformation of Chlorpyrifos Shewanella oneidensis MR-1 in the Presence of Goethite: Experimental Optimization and Degradation Products.

In this study, the degradation system of Shewanella oneidensis MR-1 and goethite was constructed with chlorpyrifos as the target contaminant. The effects of initial pH, contaminant concentration, and temperature on the removal rate of chlorpyrifos during the degradation process were investigated. The experimental conditions were optimized by response surface methodology with a Box-Behnken design (BBD). The results show that the removal rate of chlorpyrifos is 75.71% at pH = 6.86, an initial concentration of 19.18 mg·L-1, and a temperature of 30.71 °C. LC-MS/MS analyses showed that the degradation products were C4H11O3PS, C7H7Cl3NO4P, C9H11Cl2NO3PS, C7H7Cl3NO3PS, C9H11Cl3NO4P, C4H11O2PS, and C5H2Cl3NO. Presumably, the degradation pathways involved are: enzymatic degradation, hydrolysis, dealkylation, desulfur hydrolysis, and dechlorination. The findings of this study demonstrate the efficacy of the goethite/S. oneidensis MR-1 complex system in the removal of chlorpyrifos from water. Consequently, this research contributes to the establishment of a theoretical framework for the microbial remediation of organophosphorus pesticides in aqueous environments.

Manganese-Doped Carbon Quantum Dots (CQDs) Prepared from Bovine Bone Powder and Their Application for the Fluorescent Determination of Chlorpyrifos

Employing a one-step hydrothermal method with bovine bone powder as the carbon source, Mn-doped fluorescent carbon quantum dots were synthesized. Experimental investigations were conducted on their morphology, structure, composition, and optical properties. The experiments were carried out at 280 °C, pH 7.0, and a reaction period of 12 h. A rapid residual method for organophosphorus pesticides (OPs) was developed based on the fluorescence quenching of quantum dots. A linear correlation between fluorescence quenching and OP concentration was established. Chlorpyrifos was chosen as the analyte for method evaluation. The findings showed that the fluorescence intensity of the Mn-BQDs decreased with the copper ion concentration. Furthermore, the influence of copper ions on the fluorescence quenching of carbon quantum dots varied with pH. At pH 7, copper ions exhibited optimal quenching with a detection limit of 5.8 × 10−4 mg/L. This method offers simplicity in operation and environmental friendliness, rendering it well-suited for the swift on-site screening of OPs.

TRPV4 modulation participates in paraoxon-induced brain injury via NMDA and NLRP3 regulation

ABSTRACT Background Organophosphorus pesticide poisoning can lead to severe brain damage, but the specific mechanisms involved are not fully understood. Our research aims to elucidate the function of the TRPV4 ion channel in the development of brain injury induced by paraoxon (POX). Methods In vivo, we examined the survival rate, behavioral seizures, histopathological alterations, NMDA receptor phosphorylation, as well as the expression of the NLRP3-ASC-caspase-1 complex and downstream inflammatory factors in the POX poisoning model following intervention with the TRPV4 antagonist GSK2193874. In vitro, we investigated the effects of GSK2193874 on NMDA-induced inward current, cell viability, cell death rate, and Ca2+ accumulation in primary hippocampal neurons. Results The treatment with the TRPV4 antagonist increased the survival rate, suppressed the status epilepticus, improved pathological damage, and reduced the phosphorylation level of NMDA receptors after POX exposure. Additionally, it inhibited the upregulation of NLRP3 inflammasome and inflammatory cytokines expression after POX exposure. Moreover, the TRPV4 antagonist corrected the NMDA-induced increase in inward current and cell death rate, decrease in cell viability, and Ca2+ accumulation. Conclusion TRPV4 participates in the mechanisms of brain injury induced by POX exposure through NMDA-mediated excitotoxicity and NLRP3-mediated inflammatory response.

A molecularly imprinted electrochemical sensor MIP/Cu-MOF/rGO/AuNPs/GCE for highly sensitive detection of electroneutral organophosphorus pesticide residues.

A novel electrochemical sensor, MIP/Cu-MOF/rGO/AuNPs/GCE, was developed by depositing gold nanoparticles, coating Cu-MOF/GO on the surface of glassy carbon electrode (GCE) before electroreducing graphene oxide (GO) to rGO and covering molecularly imprinted membrane by electropolymerization for highly sensitive detection of electroneutral organophosphorus pesticide residues in agricultural product. Cyclic voltammetry, differential pulse voltametry, scanning electron microscopy, energy-dispersive spectroscopy, and atomic force microscopy were used to characterize the imprinted sensor. Several key factors such as chitosan concentration, suspension volume, pH of polymerization solution, and polymerization scanning rate during preparation of the imprinted sensor were optimized in detail. When electroneutral phosmet was used as a template, the linear range of MIP/Cu-MOF/rGO/AuNPs/GCE for detecting phosmet was 1.00 × 10-14-5.00 × 10-7 mol/L with the limit of detection of 7.20 × 10-15 mol/L at working potentials of - 0.2 to 0.6 V. The selectivity, reproducibility, and repeatability of MIP/Cu-MOF/rGO/AuNPs/GCE were all acceptable. The recoveries of this method for determining phosmet in real samples ranged from 94.2 to 106.5%. The MIP/Cu-MOF/rGO/AuNPs/GCE sensor could be applied to detect electroneutral pesticide residues in organisms and agricultural products.

PH-responsive dual-emission carbon dots for the ratiometric detection of organophosphorus pesticides in Brassica chinensis and Hg2+ in water

Accurate and rapid monitoring of organophosphorus pesticides (OPs) residues is crucial for regulating food safety. Herein, dual-emission carbon dots (de-CDs) were fabricated for the ratiometric detection of OPs and Hg2+. The de-CDs exhibited two emission peaks at 678 and 485 nm when excited with visible light. Interestingly, the fluorescence at 678 nm was significantly quenched by Hg2+ mainly because of the static quenching effect, whereas that at 485 nm exhibited a slight change. More significantly, the quenched fluorescence of the de-CDs recovered remarkably after introducing omethoate, diazinon and malathion. Accordingly, the ratiometric detection of the three OPs and Hg2+ was achieved with high selectivity and robust performance. In addition, the OPs residues assay in Brassica chinensis was successfully performed with satisfactory results. This study not only provides an attractive tool for the simple and rapid assay of OPs but also offers new insights into the fabrication of multi-functional carbon dots.

Surface-Enhanced Raman Spectroscopy Detection for Fenthion Pesticides Based on Gold Molecularly Imprinted Polymer Solid-State Substrates.

Current label-free surface-enhanced Raman spectroscopy (SERS) assay for the detection and analysis of organophosphorus pesticides has achieved initial success, but the application still faces constraints of substrate portability and specificity. To this end, this paper demonstrates a method for portable, rapid, and specific detection of low concentrations of fenthion pesticides based on a solid substrate of gold nanoparticle monolayers combined with molecularly imprinted polymers (MIPs). The nano-monolayers were transferred to the surface of mercapto-silicon wafers by interfacial self-assembly technique to form a stable connection with S-Au bonds and, at the same time, prevent nanoparticles from dropping off during the surfactant removal process. Then, the fenthion MIPs were directly generated on the surface of the monolayer film by spin-coating with a pre-polymerization solution and ultraviolet-induced polymerization. Tests showed that the molecular imprint was able to accurately bind to fenthion, but not other molecules, in a mixture of structural analogs, achieving a low concentration detection of 10-8 mol/L. The composite substrate maintained a signal uniformity of a relative standard deviation (RSD) = 7.05% and a batch-to-batch reproducibility of RSD = 10.40%, making it a potential pathway for the extended application of SERS technology.

Upconversion-based hydrogel kit with Python-assisted analysis platform for sample-to-result detection of organophosphorus pesticide

On-site quantitative analysis of pesticide residues is crucial for monitoring environmental quality and ensuring food safety. Herein, we have developed a reliable hydrogel portable kit using NaYbF4@NaYF4: Yb, Tm upconversion nanoparticles (UCNPs) combined with MnO2 nanoflakes. This portable kit is integrated with a smartphone reader and Python-assisted analysis platform to enable sample-to-result analysis for chlorpyrifos. The novel UCNPs maximizes energy donation to MnO2 acceptor by employing 100 % of activator Yb3+ in the nucleus for NIR excitation energy collection and confining emitter Tm3+ to the surface layer to shorten energy transfer distance. Under NIR excitation, efficient quenching of upconversion blue-violet emission by MnO2 nanoflakes occurs, and the quenched emission is recovered with acetylcholinesterase-mediated reactions. This process allows for the determination of chlorpyrifos by inhibiting enzymatic activity. The UCNPs/MnO2 were embedded to fabricate a hydrogel portable kit, the blue-violet emission images captured by smartphone were converted into corresponding gray values by Python-assisted superiority chart algorithm which achieves a real-time rapid quantitative analysis of chlorpyrifos with a detection limit of 0.17 ng mL−1. At the same time, pseudo-color images were also added by Python in “one run” to distinguish images clearly. This sensor detection with Python-assisted analysis platform provides a new perspective on pesticide monitoring and broadens the application prospects in bioanalysis.

Determination of pesticide residues and heavy metals in Adhatoda Vasaka Linn.

Heavy metals and pesticide residue analysis plays an important role in the quality control of medicinal plants like Vasaka (Adhatoda vasica). Hence a study was conducted to determine heavy metals and pesticide residues in this medicinal herb, which is a highly useful commodity in the health system. The reliable, rapid and nontoxic sample preparation method like QuEChERS and analytical methods like GC-MS were proposed for the simultaneous determination of pesticide residues and Heavy metal detection was carried out by ICP-MS. In this study, the presence of organophosphorus and organochlorine pesticides like alachlor, heptachlor, heptachlor epoxide, aldrin, dieldrin, endrin, etc was checked but not detected. Heavy metals like Arsenic (As), Cadmium (Cd), Mercury (Hg) and Lead (Pb) are traced in samples about 2.3005 ppb, 0.799 ppb, 2.290 ppb and 10.204 ppb respectively in the present study.

CdTe@ZnS quantum dots for rapid detection of organophosphorus pesticide in agricultural products

Organophosphorus pesticides (OPPs) constitute the most widely employed class of pesticides. However, the prevalent use of OPPs, while advantageous, raises concerns due to their toxicity, posing serious threats to food safety. Chemical sensors utilizing quantum dots (QDs) demonstrate promising applications in rapidly detecting OPPs residues, thereby facilitating efficient inspection of agricultural products. In this study, we employ an aqueous synthesis approach to prepare low toxic CdTe@ZnS QDs with stable fluorescence properties. To mitigate the risk of imprecise measurements stemming from the inherent susceptibility of fluorescence to quenching, we have adopted the principle of fluorescence resonance energy transfer (FRET) for the construction of the turn-on quantum dot sensor. With a detection limit for chlorpyrifos as low as 10 ppb (10 μg/L), the QDs sensor exhibits notable resistance to interference from various pesticides. Application of this system to detect organophosphorothioate pesticides in apples produced results consistent with those obtained from high-performance liquid chromatography (HPLC) detection, affirming the promising application prospects of this sensing system for the rapid detection of OPPs residues.

Multifunctional 2D hemin-bridged MOF for the efficient removal and dual-mode detection of organophosphorus pesticides.

The high-residual and bioaccumulation property of organophosphorus pesticides (OPs) creates enormous risks towards the ecological environment and human health, promoting the research for smart adsorbents and detection methods. Herein, 2D hemin-bridged MOF nanozyme (2D-ZHM) was fabricated and applied tothe efficient removal and ultrasensitive dual-mode aptasensing of OPs. On the one hand, the prepared 2D-ZHM contained Zr-OH groups with high affinity for phosphate groups, endowing it with selective recognition and high adsorption capacity for OPs (285.7mgg-1 for glyphosate). On the other hand, the enhanced peroxidase-mimicking biocatalytic property of 2D-ZHM allowed rapid H2O2-directed transformation of 3,3',5,5'-tetramethylbenzidine to oxidic product, producing detectable colorimetric or photothermal signals. Using aptamers of specific recognition capacity, the rapid quantification of two typical OPs, glyphosate and omethoate, was realized with remarkable sensitivity and selectivity. The limit of detections (LODs) of glyphosate were 0.004nM and 0.02nM for colorimetric and photothermal methods, respectively, and the LODs of omethoate were 0.005nM and 0.04nM for colorimetric and photothermal methods, respectively. Theconstructed dual-mode aptasensing platform exhibited outstanding performance for monitoring OPs in water and fruit samples. This work provides a novel pathway to develop MOF-based artificial peroxidase and integrated platform for pollutant removal and multi-mode aptasensing.

Nanobodies-based colloidal gold immunochromatographic assay for specific detection of parathion

Parathion is one of organophosphorus pesticide, which has been prohibited in agricultural products due to its high toxicity to human beings. However, there are still abuse cases for profit in agricultural production. Hence, we established nanobodies-based colloidal gold immunochromatographic assay (GICA) in which nanobodies (Nbs) as an excellent recognition element, greatly improving the stability and sensitivity of ICA. Under the optimal conditions, the developed Nbs-based GICA showed a cut-off value of 50 ng/mL for visual judgment and a half-inhibitory concentration (IC50) of 2.39 ng/mL for quantitative detection. The limit of detection (LOD) was as low as 0.15 ng/mL which was significantly 50-fold higher sensitivity than the commercial mAb-ICA. Additionally, this method exhibited good recoveries for the detection of cabbage, cucumber, and orange samples and excellent correlation with the UPLC-MS/MS method. The results showed that this method developed in this work based on nanobody can be used in practical detection of parathion in foods and nanobody is novel prospective antibody resource for immunoassays of chemical contaminants.

A faster and more accessible method for the analysis of acephate and methamidophos in water samples by LC-MS/MS

ABSTRACT Pesticide pollution on environmental matrices has attracted increasing attention worldwide. Pesticide runoff from agricultural crops into surface waters may impact ecosystems and human health through drinking water consumption in pesticide-polluted areas. This study aims to develop and validate a simpler, faster, and more accessible methodology for the analysis of organophosphate pesticides, such as acephate and methamidophos, using HPLC-ESI-MS (QqQ). Acephate and methamidophos are two of the most common and efficient systemic pesticides in the organophosphate family, known for their high effectiveness against insects and pests. Firstly, different extractions were tested: liquid-liquid extraction (LLE), low-temperature partitioning extraction (LTPE) and solid-phase extraction (SPE) with a usual and accessible cartridge, C18. LLE and LTPE showed low sensitivities, probably because acephate and methamidophos are extremely hydrophilic compounds, like many organophosphorus pesticides. Thus, they have low interaction with the extractor solvent, resulting in low extraction rates. SPE with C18 cartridge led to the best extraction of acephate and methamidophos in water matrices and was chosen for the validated process. The selected method ensured acceptable recoveries, within the same range found in the scientific literature (9–49%) and within relative standard deviations below 20%. However, future efforts regarding other types of cartridges are encouraged. The limit of detection (LOD) and limit of quantification (LOQ) of the analytical method were 0.2 µg/L and 0.5 µg/L for acephate and methamidophos, values lower than those reported in the scientific literature. The developed method was used to quantify the levels of such organophosphate pesticides in samples from Brazilian surface water and none of the target pesticides were detected in these aquatic matrices.

Determination of Concentrations of Pesticide Residues in Chevon obtained from Abattoir of Jimeta, Adamawa State, Nigeria

The current work was aimed at determining levels of Organochlorine (OCP) and Organophosphorus pesticide (OPP) residues in goats obtained from the study area. This was to enable the public aware of the presence of hazardous pesticides residues in the food chain. Forty samples were collected from; Chevon, intestines, kidneys and livers of ten sampled goats. The sampled goats were represented by G1 = first goat, G2 = second goat, G3 = third goat, G4 = fourth goat, G5 = fifth goat, G6 = sixth goat, G7 = seventh goat, G8 = eighth goat, G9 = ninth goat and G10 = tenth goat. Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) was used in preparing the samples. Analysis was done with Gas chromatography – Mass spectrometer (GC/MS) Acqmethod pesticide. Results showed that OCP residues were not detected in all the samples. Anthracene, dichlorpyrifos, diazinon, dimethoate, primifos-methyl, and malathion were detected below the threshold value of 0.001 mg/Kg. Likewise, all pesticide residues in G7 and G9 samples were below the threshold limit (0.001) mg/Kg. Dichlorvos wasdetected in chevon of G1, G3 and G4 with range from 0.043 mg/Kg in G4 – 0.113 mg/Kg in G1. Chlorpyrifos was detected in intestine of G1, G2, G3, G4, G6, G8 and G10. The highest was 0.051 mg/Kg in G4 and lowest was 0.013 mg/Kg in G10. Kidney samples of GI, G2, G3 and G4 contained chlorpyrifos ranging from 0.011 mg/Kg in G8 – 0053 mg/Kg in G4. dichlovos was detected in kidney samples of G1, G2, G3, G4 and G8. Highest concentration of dichlovos in the kidney was; 0.069 00014 mg/Kg in G1 while the lowest was in G8 (0.011mg/Kg). Liver samples of G2, G4, G6 and G10 contained chlopyrifos ranging from 0,007 mg/Kg in G10 – 0.050 mg/Kg in G4. dichlovos was present in livers of G2, G4 and G6. Highest was in G4 (0.037 mg/Kg) and lowest value was in G6 (0.021 mg/Kg). Apart from in Kidney of G8, concentrations of chlorpyrifos in all the samples were above the maximum residue level (MRL) values of 0.01 mg/Kg. Consumption of which may pose health problem. Concentration of dichlorvos detected in the samples were below the MRL of 1.00mg/Kg, this may not pose immediate health issues but continuous intake may bring about accumulative health risk issues. Keywords: Chevon, chlorpyrifos, dimethoate, organophosphorus, malathion, dichlorvos, health, risk

De novo synthesis of a novel hapten and development of a monoclonal antibody–based immunoassay for the detection of dichlorvos and trichlorfon

The absence of high-affinity antibodies has hindered the development of satisfactory immunoassays for dichlorvos (DDVP) and trichlorfon (TCP), two highly toxic organophosphorus pesticides. Herein, the de novo synthesis of a novel anti-DDVP hapten was introduced. Subsequently, a specific anti-DDVP monoclonal antibody (Mab) was produced with satisfying affinity to DDVP (IC50: 12.4 ng mL−1). This Mab was highly specific to DDVP, and TCP could readily convert into DDVP under mild alkaline conditions. Leveraging this insight, an indirect competitive ELISA was successfully developed for simultaneous detection of DDVP and TCP. The limit of detection in rice, cabbage and apple for DDVP /TCP was found to be 12.1/14.6 μg kg−1, 7.3/8.8 μg kg−1 and 6.9/8.3 μg kg−1, respectively. This study not only provides an effective strategy for producing a high-quality anti-DDVP Mab but also affords a reliable and cost-effective tool suitable for high-throughput detection of DDVP and TCP in food samples.

Sustainable and efficient degradation of chlorpyrifos by the synergy mixed Fe–Al (ZVI@Almix) bimetallic particles: Performance and mechanism

Chlorpyrifos (CPF) is one of the most widely used pesticides in the world, and its improper use will cause serious pollution to ecological safety and water environment. There is an urgent need for an efficient, environmental-friendly, and cost-effective removal technology. ZVI@Almix (mixed zero-valent iron and aluminum) is a potential technology for degrading CPF by combining it with ZVI (zero-valent iron), ZVAl (zero-valent aluminum) and ZVI@Alsup (supported zero-valent iron and aluminum). This technology can efficiently degrade CPF, achieving a removal rate of 93.47% and a complete mineralization rate of 62.15% at the concentration of 10 mg/L, pH of 7.0, temperature of 25 °C, and ZVI@Almix dosage of 0.30 g/L, and can effectively alleviate the interference of anions and HA in actual wastewater. The elemental evolution and solution composition of ZVI@Almix indicates that the material has an activation effect on O2 in solution. The existence of •OH and O2−• in the reaction and the degradation of CPF were confirmed by quenching experiments and electron spin resonance. In addition, Al provides electronic output for ZVI, which prolongs the life of ZVI and guarantees the sustainable degradation ability of ZVI@Almix. The detection of pollutant degradation intermediates initially proposed two degradation pathways, the cleavage of C–O–P bonds, and the substitution of S and methyl groups. DFT calculation proves that pathway Ⅰ is more favorable in the reaction process, and the toxicity assessment also shows that the product toxicity of pathway Ⅰ is slightly lower than that of pathway Ⅱ. Finally, ZVI@Almix has strong reusability, the removal rate of CPF in the fourth reuse process can still reach 80.91%, and the material recovery in the fifth time can still reach 80.46%. This study proposed a mechanism to degrade CPF using cheap bimetallic particles and confirmed its feasibility through practice and theory. These findings not only provide an efficient, green, and economical pollution control technology for the removal of organophosphorus pesticides in the wastewater but also provide new ideas for the application of ZVI-based bimetallic materials in the field of environmental governance.