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At land-sea interface, mangroves are likely to be exposed to pesticides due to agricultural run-offs. In Mayotte Island (Comoros archipelago, Mozambique Channel), dimethoate (DMT) is found in high concentrations in tomatoes, but no data confirm its presence in mangroves. We aimed at screening the presence of DMT in three mangroves of Mayotte at different levels (highest point above crops, village, upstream mangrove, downstream mangrove) and assessing the impact of DMT coupled with reduced salinity on mangrove crab physiology. To do so, we performed 24-h exposures at sublethal concentrations (10 and 100 µg L−1) corresponding to 100 × and 1000 × the environmental standard (no data exist on environmental concentrations), in seawater (SW) and diluted SW (dSW). We exposed male fiddler crab Tubuca urvillei, one of the most common fiddler crabs living in mangrove areas regularly flooded and exposed to agricultural run-offs. Different physiological endpoints were considered: behaviour, acetylcholinesterase (AChE) activity, muscle energy metabolism, DNA oxidative damage and osmoregulatory capacity using hemolymph samples, posterior gills and claw muscle. We confirmed the presence of DMT in one mangrove and the effect of pesticide exposure at the different endpoints. Changes in behavioural and physiological parameters highlighted in this study could warn us of recent pesticide use upstream and help us understand past or future community-level changes in mangrove ecosystems affected by pesticide inputs. [ABSTRACT FROM AUTHOR]

In this study, amino functionalized cellulose nanocrystals–polyethersulfone nanocomposite membrane (A-CNC/PES) based on agricultural waste was used for the removal of diazinon (DZ) from aqueous solution. The fabricated membrane has been characterized via attenuated total reflectance-Fourier transform infrared (ATR-FTIR), scanning electron microscopy (SEM), dispersive X-ray spectrometer (EDX), X-ray diffractometer (XRD), thermal gravimetric analysis (TGA), water contact angel (WCA), porosity, and mean pore radius. The effect of variables, such as initial DZ concentration, pH, and A-CNC content, on the membrane performance was optimized using response surface methodology (RSM) through central composite design (CCD). The results indicated that the additive had the most significant effect on the hydrophilicity improvement, reducing surface roughness, and reducing fouling. The highest removal efficiency of A-CNC/PES membrane for DZ was about 99.3% (at A-CNC: 0.2 wt%), and more than three-fold water flux improvement (27.3 versus 8.3 kg/m2.h for unmodified membrane) was attained. The results of antifouling test confirmed that the A-CNC/PES membranes had a high-flux recovery (FRR: 90.05%). This study may provide promising insights for the development of next generation of agricultural waste-based nanocomposite membrane in the water and wastewater treatment. Highly efficient removal of diazinon pesticide from aqueous solutions by using grape branch-derived CNCs-PES nanocomposite membrane. [ABSTRACT FROM AUTHOR]

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). 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. 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. TRPV4 participates in the mechanisms of brain injury induced by POX exposure through NMDA-mediated excitotoxicity and NLRP3-mediated inflammatory response. [ABSTRACT FROM AUTHOR]

This study compares the properties of B12N12 and Si12C12 nanoclusters functionalized with tyrosine in the adsorption of organophosphorus pesticides, focusing on adsorption energy and electronic stability. The results indicate that B12N12/tyrosine exhibits more negative adsorption energies than Si12C12/tyrosine, suggesting stronger interactions and higher adsorption stability. Additionally, B12N12 demonstrates higher ionization energy and chemical hardness, enhancing its electronic stability during the adsorption process. In contrast, Si12C12 has higher electrophilicity and maximum electron transfer capacity, leading to greater variability in adsorption energy and more flexible electronic structure adjustments. These findings suggest that B12N12 nanoclusters have greater potential and application value as adsorption materials, particularly when modified with tyrosine. B12N12/tyrosine demonstrates higher stability and predictability in pesticide adsorption, making it more suitable for related applications. [ABSTRACT FROM AUTHOR]

Dates are rich in nutrients, making them popular all over the world as healthy fruits. Due to the use of pesticides by gardeners to control pests in date palm farms, date fruits may contain pesticides, which could potentially endanger the health of consumers. In this study, date fruit samples at three different growth stages (green fruit, unripe date, date) were collected from the groves of Khesht city. The residues of 15 organophosphorus pesticides in water-washed and unwashed samples were measured using gas chromatography-mass spectrometry (GC–MS). The results showed that the residue levels of all organophosphorus pesticides measured were below the maximum residue limits recommended by FAO and CODEX. Based on the data, washing date fruits with water can effectively reduce the residual amount of organophosphorus pesticides, thereby helping to reduce the intake of pesticides. Moreover, the results of the risk assessment showed that consumption of unripe and ripe dates from Khesht has no carcinogenic (

Extensive use of pesticides in agricultural production has been causing serious health threats to humans and animals. Among them, phorate is a highly toxic organophosphorus insecticide that has been widely used in planting. Due to its harmful effects on human and animal health, it has been restricted for use in many countries. Analytical methods for the rapid and sensitive detection of phorate residues in agricultural products are urgently needed. In this study, a new method was developed by combining surface-enhanced Raman spectroscopy (SERS) and immunochromatography assay (ICA). Hybrid magnetic Fe3O4@Au@DTNB-Ab nanoprobes were prepared by modifying and growing Au nanoseeds on an Fe3O4 core. SERS activity of the nanoprobe was optimized by adjusting the concentration of the Au precursor. A rapid and sensitive assay was established by replacing the traditional colloidal gold-based ICA with hybrid SERS nanoprobes for SERS-ICA. After optimizing parameters including coating antibody concentrations and the composition and pH of the buffer solution, the limit of detection (LOD) for phorate could reach 1 ng/mL, with a linear range of 5~100 ng/mL. This LOD is remarkably lower than the maximum residue limit in vegetables and fruits set by the Chinese government. The feasibility of this method was further examined by conducting a spiking test with celery as the real sample. The result demonstrated that this method could serve as a promising platform for rapid and sensitive detection of phorate in agricultural products. [ABSTRACT FROM AUTHOR]

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 to the 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 (285.7 mg g−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 0.004 nM and 0.02 nM for colorimetric and photothermal methods, respectively, and the LODs of omethoate were 0.005 nM and 0.04 nM for colorimetric and photothermal methods, respectively. The constructed 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. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Organophosphorus pesticides (OPPs) having a phosphate ester moiety, such as malathion (MA) and methidathion (DMTP), are widely used and have been detected in many fatal cases of accidental exposure or suicide in Japan. In forensic toxicology, the accurate determination of blood OPP concentration is mandatory to prove death by OPP poisoning. However, fatal pesticide concentration in blood at autopsy varies depending on the circumstances surrounding the dead body. In this study, we found that 16 OPPs were degraded by human serum albumin (HSA) in a temperature-dependent fashion. The mechanism underlying MA, DMTP, azinphos-methyl, etrimfos, fenthion (MPP), pirimiphos-methyl, (E)-dimethylvinphos, (Z)-dimethylvinphos, vamidothion, edifenphos (EDDP), fosthiazate, and pyraclofos degradation involves the formation of adducts with tyrosine residues in HSA. The mass spectra obtained by liquid chromatography quadrupole Orbitrap mass spectrometry revealed that phosphate ester amino acid adducts such as Y-adduct1, Y-adduct2, Y-adduct3, Y-adduct4, and Y-adduct5 were formed in HSA solution incubated with OPPs. These results indicate that the 16 OPPs are postmortem changed by HSA. The detection of phosphate ester amino acid adducts such as Y-adduct1, Y-adduct2, Y-adduct3, Y-adduct4, and Y-adduct5, instead of MA, DMTP, azinphos-methyl, etrimfos, MPP, pirimiphos-methyl, (E)-dimethylvinphos, (Z)-dimethylvinphos, vamidothion, EDDP, fosthiazate, and pyraclofos per se , may be used to determine death by these OPPs poisoning. [ABSTRACT FROM AUTHOR]

Organophosphorus pesticides rank among the most extensively used pesticides in agriculture, leading to widespread contamination of water bodies, soil, and vegetation, thereby disrupting ecosystems and posing health risks. Consequently, rapid and precise detection of organophosphorus pesticide residues is crucial for effective pesticide management. Conventional analytical methods such as chromatography and spectroscopy rely on sophisticated equipment and specialized personnel, incurring high costs and time consumption. In response, this study presents an innovative approach involving the development of aptamer-based colloidal gold lateral flow test strips for the swift and accurate detection of residual organophosphorus pesticides in fruits and vegetables. These test strips offer advantages such as sensitivity, portability, and ease of operation, enabling on-site application in real sample detection and demonstrating excellent applicability. Furthermore, the logical operation process of these test strips facilitates science popularization and education. Diverse experimental processes and schemes tailored for different audiences serve to stimulate interest in chemistry and science while enhancing awareness of food safety. [ABSTRACT FROM AUTHOR]

A simple and sensitive colorimetric method for organophosphorus pesticides (Ops) detection was proposed via a multi-enzyme cascade reaction. The coordination compound of wool keratin and Cu (WK-Cu) was synthesized by self-assembly and used as a key catalyst in the cascade reaction. The enzymatic kinetics curve was established to explore the catalytic property, and the obtained Km and Vmax proved that WK-Cu has a good peroxidase-like activity. Ops could inhibit acetylcholinesterase activity and trigger the multienzyme cascades process, resulting in an amplified response signal. The key conditions were optimized, such as enzyme-linked reaction time and the concentration of each reactant in Ops detection. The detection range of phoxim was 10-1000 µg/L with a detection limit of 2.31 µg/L. Compared with other colorimetric detections, the proposed method exhibited a wider detection range and a relatively lower detection limit. In addition, this colorimetric method showed good universality and anti-interference ability for the analysis of phoxim in apple, cabbage and cauliflower samples. Owing to these merits, the proposed method has a good application prospect in Ops detection. [ABSTRACT FROM AUTHOR]

While pesticides help prevent crop loss, overuse is damaging to the environment and can cause many health issues. The main intention of the present study was to detect and assess different pesticide residues on paddy field soils at Chittur Taluk in Palakkad, India. Approximately 72 soil samples were collected from different paddy fields at Chittur immediately after two weeks of the application of pesticides. The commonly used pesticides by farmers in Chittur include Almix, BACT 805, Emida, Chilli King, Ekalux, Fenval, Glycel, Karate, Nuvan, Sultan 505, and Takila. We screened for the presence of 38 pesticides using the QuEChERS-PRRAL/MOA-08 method, and chlorpyrifos and dichlorvos were detected. The results indicated the steps to be taken for controlling pesticide residues in paddy field soils for a healthy, sustainable ecosystem for long-term farming activities and biodiversity protection. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Herein, a deep eutectic solvent (DES)‐based miniaturized pressurized liquid extraction in combination with DES‐based dispersive liquid–liquid microextraction (DLLME) was developed for the extraction of organophosphorus pesticides (parathion–methyl, triazophos, parathion, diazinon, and phoxim) from egg powder samples prior to their analysis by a high‐performance liquid chromatography‐diode array detector. In this work, first, the analytes' extraction was done by a pressurized liquid phase extraction for effective extraction of the analytes from the solid matrix, and then they were concentrated on a DLLME for more concentration of the analytes to reach low limits of detections. The use of DESs was done in both steps to omit the use of toxic organic solvents. Satisfactory results including high extraction recoveries (74–90%), great repeatability (relative standard deviations equal or less than 4.3% and 5.3% for intra‐ and inter‐day precisions), and low limits of detection (0.11–0.29 ng/g) and quantification (0.38–0.98 ng/g) were attained under the optimum conditions. Lastly, the suggested approach was utilized for the determination of the studied pesticides in various egg powder samples marketed in Tabriz, Iran. [ABSTRACT FROM AUTHOR]

Dried corn was crushed to prepare samples, and the method of QuEChERS for extracting organophosphorus pesticides from corn was optimized, the economic and rapid extraction of organophosphorus pesticide residues in corn was realized, and gas chromatography triple quadrupole tandem mass spectrometry was established to qualitatively and quantitatively detect organophosphorus pesticides in samples. The results showed that the limit of detection(LOD) of seven organophosphorus pesticides was 0. 03-0. 49 μg / kg, limit of quantification(LOQ) was 0. 08-1. 62 μg / kg; the relative standard deviation (RSD) was 2. 2%-16. 7%, and the recovery rate was 63. 8%-122. 3%. This method had the characteristics of simplicity, fast response, high recovery rate, high sensitivity and strong resistance to matrix interference, and its suitable for the analysis and detection of organic phosphorus pesticides in corn crops. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, a flexible electrochemical sensor was developed for the detection of organophosphorus pesticides (OPs). To fabricate the sensor, graphene was generated in situ by laser-induced graphene (LIG) technology on a flexible substrate of polyimide (PI) film to form a three-electrode array, and pralidoxime (PAM) chloride was used as the probe molecule. CeO2 was used to modify the working electrode to improve the sensitivity of the sensor because of its electrocatalytic effect on the oxidation of PAM, and the Ag/AgCl reference electrode was prepared by the drop coating method. The effects of the laser power, laser scanning speed, and CeO2 modification on the electrochemical properties of the sensor were studied in detail. The results prove that the sensor has good repeatability, stability, and anti-interference ability, and it shows an excellent linear response in the chlorpyrifos concentration range from 1.4 × 10−8 M to 1.12 × 10−7 M with the detection limit of 7.01 × 10−10 M. [ABSTRACT FROM AUTHOR]

• Heterogeneous kinetics of fenthion and parathion toward OH radicals was studied. • OH radicals play an important role in their atmospheric degradation. • A negative RH and a positive temperature dependences of kinetics were observed. • Heterogeneous rate constants and atmospheric lifetimes were obtained. Fenthion and parathion are two representative kinds of organophosphorus pesticides and widely used in agriculture. They are directly or indirectly released into the atmosphere by spraying or volatilization processes. However, their heterogeneous reactivity toward OH radicals has not yet been well understood. Therefore, this work investigated the heterogeneous kinetics of the OH-initiated degradation of surface-bound fenthion and parathion using a flow reactor. The results showed that OH radicals played an important role in the atmospheric degradation of fenthion and parathion. Their average rate constants were (7.20 ± 0.77) × 10−12 and (10.40 ± 0.60) × 10−12 cm3/(mol· sec) at a relative humidity (RH) and temperature of 35% and 20 °C, respectively, suggesting that they have relatively short lifetimes in the atmosphere. In addition, a negative RH dependence and a positive temperature dependence of the rate constants were observed. The Arrhenius expressions of fenthion and parathion were k 2 = (1.34 ± 0.48) × 10−9exp[−(1432.59 ± 105.29)/T] and k 2 = (1.96 ± 1.38) × 10−9exp[−(1619.98 ± 222.02)/T], respectively, and their overall activation energy was estimated to be (11.88 ± 0.87) and (13.48 ± 1.83) kJ/mol. The experimental results will update the kinetic data of fenthion and parathion in the atmosphere and be helpful to further understand their atmospheric transportation processes. [Display omitted] [ABSTRACT FROM AUTHOR]

Objectives] To understand the quality safety of vegetables produced in vegetable planting bases around Lhasa City. [Methods] Four vegetable planting bases in the east, west, south, and north of Lhasa City were randomly selected for testing using rapid measuring instru- ment for agricultural residues and solid-phase microextraction-gas chromatography-mass spectrometer, with 120 vegetable samples selected. The testing samples included seven categories: green leafy vegetables, eggplants, melons, onions and garlic, root vegetables, beans, and fungi, totaling 29 types of vegetables. The samples were tested for 8 common prohibited and restricted pesticides in organic phosphorus and carbamate esters, including methamidophos, parathion, methyl parathion, monocrotophos, isocarbophos, methamidophos, aldicarb, and carbofuran. [Results] The pesticide inhibition rate of 6 kinds of vegetables detected by the rapid measuring instrument for agricultural residues was relatively high, with green leafy vegetables being the majority, reaching over 25%. By further establishing a solid-phase microextraction-gas chromatography-tandem mass spectrometry method, the accuracy of the data was verified experimentally. The experimental results indicated that the inhibition rate of vegetable samples in this experiment did not exceed 15%, and it was determined as a pollution-free vegetable. [Conclusions] According to the restriction standard of national pesticide use, the inhibition rate of vegetable samples was less than or equal to 40%, indicating that the quality of vegetables was qualified. [ABSTRACT FROM AUTHOR]

Methyl parathion (MP), an organophosphorus insecticide, is commonly used in agricultural products for food preservation and pest control. Due to the severe threat it poses to food safety and the environment, monitoring MP residues has attracted much attention. Traditional spectroscopic and chromatographic methods have been used successfully to analyze MP in a wide range of samples; however, these approaches have several drawbacks, such as requiring specialized equipment, trained technicians, and extensive sample preparation time. Due to these restrictions, there is a growing demand for analysis methods that can reliably and quickly detect MP at trace quantities while also being quick, sensitive, and selective. Electrochemical sensors have emerged over the past few decades as a viable alternative to more time-consuming and laborious analysis methods for detecting MP. However, the performance of electrochemical sensors has been dramatically improved thanks to recent breakthroughs in nanoscience. This study offers an overview of the creation and operation of carbon nanomaterial-based electrochemical sensors (including carbon nanotubes (CNTs), graphene (Gr), and other carbon nanomaterials) to identify MP residues in waters, fruits, and vegetables. A brief discussion of the potential benefits, drawbacks, and future research prospects of MP electrochemical sensors based on carbon nanomaterials is also offered. [ABSTRACT FROM AUTHOR]

This study compares the properties of B12N12 and Si12C12 nanoclusters functionalized with tyrosine in the adsorption of organophosphorus pesticides, focusing on adsorption energy and electronic stability. The results indicate that B12N12/tyrosine exhibits more negative adsorption energies than Si12C12/tyrosine, suggesting stronger interactions and higher adsorption stability. Additionally, B12N12 demonstrates higher ionization energy and chemical hardness, enhancing its electronic stability during the adsorption process. In contrast, Si12C12 has higher electrophilicity and maximum electron transfer capacity, leading to greater variability in adsorption energy and more flexible electronic structure adjustments. These findings suggest that B12N12 nanoclusters have greater potential and application value as adsorption materials, particularly when modified with tyrosine. B12N12/tyrosine demonstrates higher stability and predictability in pesticide adsorption, making it more suitable for related applications.

Extensive use of pesticides in agricultural production has been causing serious health threats to humans and animals. Among them, phorate is a highly toxic organophosphorus insecticide that has been widely used in planting. Due to its harmful effects on human and animal health, it has been restricted for use in many countries. Analytical methods for the rapid and sensitive detection of phorate residues in agricultural products are urgently needed. In this study, a new method was developed by combining surface-enhanced Raman spectroscopy (SERS) and immunochromatography assay (ICA). Hybrid magnetic Fe3O4@Au@DTNB-Ab nanoprobes were prepared by modifying and growing Au nanoseeds on an Fe3O4 core. SERS activity of the nanoprobe was optimized by adjusting the concentration of the Au precursor. A rapid and sensitive assay was established by replacing the traditional colloidal gold-based ICA with hybrid SERS nanoprobes for SERS-ICA. After optimizing parameters including coating antibody concentrations and the composition and pH of the buffer solution, the limit of detection (LOD) for phorate could reach 1 ng/mL, with a linear range of 5~100 ng/mL. This LOD is remarkably lower than the maximum residue limit in vegetables and fruits set by the Chinese government. The feasibility of this method was further examined by conducting a spiking test with celery as the real sample. The result demonstrated that this method could serve as a promising platform for rapid and sensitive detection of phorate in agricultural products.

The safety of aquatic system has been threatened due to extensive and inappropriate application of organophosphorus pesticide methidathion (MD). Hence, a 12-day stress trial was carried out to explore the impacts of waterborne MD on acetylcholinesterase (AChE) activity, histopathology, antioxidant status and stress-related genes expression in Nile tilapia (Oreochromis niloticus). Fish (initial mean weight 60 ± 2 g) were placed in 18 tanks (volume 460 L, 30 fish/tank), with triplicate treatment groups being exposed to diverse concentrations of MD (0, 0.8, 1.67, 5.34, 7.49 and 15.83 µg/L). The results showed that AChE activities in serum and liver were inhibited by MD. After the 12-day stress trial, malonaldehyde (MDA) content in serum and liver was higher than that of 0 µg/L group when MD concentration exceeded 0.8 and 5.34 µg/L, respectively. Catalase (CAT) and total superoxide dismutase (T-SOD) activity in serum and liver revealed irregular variations. In addition, MD (＞0.8 µg/L) caused lesions in gills and liver tissues. MD also down-regulated expression of cytochrome P450 1B1, heat shock protein 70 and cytochrome c oxidase subunit 7B, which contradicted the trend of phospholipase A2 and cytochrome P450 1 A (except in the 15.83 µg/L group). In a word, waterborne MD suppressed AChE activities, induced oxidative stress and harmed the liver and gills. Additionally, it may negatively influence resistance to stress, oxidative phosphorylation, detoxification and anti-inflammatory response in Nile tilapia.

Chronic occupational exposure to organophosphorus pesticides (OPs) is consistently associated with deficits on behavioral tests when compared to unexposed comparison groups. However, a dose-response relationship has yet to be established, leading some to doubt an association between occupational OP exposure and behavioral deficits. Pesticide application teams in Egypt who are primarily exposed to one OP, chlorpyrifos (CPF), were recruited into a field assessment. Trail Making A and the more challenging Trail Making B tests were administered to 54 engineers (who supervise the pesticide application process, usually from the side of the field), 59 technicians (who guide the pesticide applicators in the field), 31 applicators (who mix and apply pesticides using knapsack sprayers), and 150 controls (who did not work in the fields) at two different times during the OP application season as well as immediately after applications had ended and 1.5 months later. All participants were males since only males work on pesticide application teams in Egypt. Urinary levels of 3,5,6-trichloro-2-pyridinol (TCPy), a specific metabolite of CPF, confirmed the pattern of lower to higher CPF exposures from engineers to technicians to applicators, and these were all greater than urinary metabolite levels in controls. A consistent relationship between job title and performance speed on the behavioral task was observed: Controls had the best (fastest) performance on Trail Making A and B tests throughout the application season, and applicators had significantly slower performance than engineers on Trail Making A (p = 0.015) and B (p = 0.003). However, individual urinary TCPy, blood acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) levels did not predict individual performance. This study identifies a dose-related effect based on job title, which serves as a surrogate for chronic exposure in that differing job titles exhibit varying group exposure levels. The results establish that chronic occupational exposure to chlorpyrifos is neurotoxic and suggest that the classic biomarkers of recent CPF exposure are not predictive of chronic exposure effects.

Boron nitride nanotubes have been widely used as drug delivery vehicles and for the controlled release of targeted therapeutic drugs. In this study, we calculated the encapsulation efficiencies of three organophosphorus pesticides, parathion, chlorpyrifos, and coumaphous, using quantum chemical methods. The results show that the encapsulation energy of zigzag BNNT(20,0) is lower than that of armchair BNNT(12,12) to encapsulate parathion. Al doping helps to decrease the encapsulation energy and Al-doped zigzag BNNT(20,0) + parathion has the greatest binding affinity. In addition, the energy gap of armchair BNNT(12,12) encapsulating organophosphorus pesticides changed significantly. Al doping reduces the band gap of boron nitride nanotubes. Al-doped armchair BNNT(12,12) has the strongest electron-accepting ability and is a promising sensor material. [ABSTRACT FROM AUTHOR]

Organophosphorus Pesticides (OPPs) are among the extensively used pesticides throughout the world to boost agricultural production. However, persistent residues of these toxic pesticides in various vegetables, fruits, and drinking water poses detrimental health effects. Consequently, the rapid monitoring of these harmful chemicals through simple and cost-effective methods has become crucial. In such an instance, electrochemical methods offer simple, rapid, sensitive, reproducible, and affordable detection pathways. To overcome the limitations associated with electrochemical enzymatic sensors, non-enzymatic sensors have emerged as promising and simpler alternatives. The non-enzymatic sensors have demonstrated superior activity, reaching detection limit up to femto (10−15) molar concentration in recent years, leveraging higher selectivity obtained through the molecularly imprinted polymers, synergistic effects between carbonaceous nanomaterials and metals, metal oxide alloys, and other alternative approaches. Herein, this review paper provides an overview of the recent advancements in the development of non-enzymatic electrochemical sensors for the detection of commonly used OPPs, such as Chlorpyrifos (CHL), Diazinon (DZN), Malathion (MTN), Methyl parathion (MP) and Fenthion (FEN). The design method of the electrodes, electrode functioning mechanism, and their analytical performance metrics, such as limit of detection, sensitivity, selectivity, and linearity range, were reviewed and compared. Furthermore, the existing challenges within this rapidly growing field were discussed along with their potential solutions which will facilitate the fabrication of advanced and sustainable non-enzymatic sensors in the future.

Surface-enhanced Raman scattering (SERS) is considered an efficient technique providing high sensitivity and fingerprint specificity for the detection of pesticide residues. Recent developments in SERS-based detection aim to create flexible plasmonic substrates that meet the requirements for non-destructive analysis of contaminants on curved surfaces by simply wrapping or wiping. Herein, we reported a flexible SERS substrate based on cellulose fiber (CF) modified with silver nanostructures (AgNS). A silver film was fabricated on the membrane surface with an in situ silver mirror reaction leading to the formation of a AgNS–CF substrate. Then, the substrate was decorated through in situ synthesis of raspberry-like silver nanostructures (rAgNS). The SERS performance of the prepared substrate was tested using 4-mercaptobenzoic acid (4-MBA) as a Raman probe and compared with that of the CF-based plasmonic substrates. The sensitivity of the rAgNS/AgNS–CF substrate was evaluated by determining the detection limit of 4-MBA and an analytical enhancement factor, which were 10 nM and ~107, respectively. Further, the proposed flexible rAgNS/AgNS–CF substrate was applied for SERS detection of malathion. The detection limit for malathion reached 0.15 mg/L, which meets the requirements about its maximum residue level in food. Thus, the characteristics of the rAgNS/AgNS–CF substrate demonstrate the potential of its application as a label-free and ready-to-use sensing platform for the SERS detection of trace hazardous substances. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Diazinon (DZN) is a refractory organophosphorus pesticide (OP) in the surrounding environment due to its overuse in agriculture. The antioxidant activity of Epigallocatechin gallate (EGCG) from green tea is at least 100 times greater than that of vitamin C. This study aimed to study the effects of DZN on the meiotic maturation of porcine oocytes, as well as the protective roles of EGCG. Firstly, the effects of DZN and EGCG on meiotic nuclear maturation of porcine oocytes were detected, and then embryonic development was investigated by chemical parthenogenetic activation. Next, the spindle assembly, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), DNA damage, and finally the early apoptosis of oocytes were examined by immunofluorescence staining. The results revealed that DZN exposure significantly reduced the quality of porcine oocytes, such as failure of nuclear and cytoplasmic maturation, evidenced by abnormal spindle assembly, disordered chromosome alignment, low MMP, observably increased ROS, severe DNA damage, and early apoptosis. Appropriate EGCG could significantly reduce all these defects caused by DZN. In conclusion, EGCG can help prevent the harm that DZN exposure can do. These findings offer convincing support for enhancing the oocyte quality from EGCG through daily ordinary beverages. • Effects of DZN and EGCG on the meiotic maturation of porcine oocytes. • EGCG protects the mitochondrial function of DZN-exposed oocytes. • EGCG reduces DNA damage and inhibits early apoptosis of DZN-exposed oocytes. [ABSTRACT FROM AUTHOR]

In the present study, β-cyclodextrin/Allyl Glycidyl Ether (AGE)/thermo-sensitive polymer was grafted onto modified Fe3O4@SiO2 to be utilised as a possible adsorbent for diazinon removal from an aqueous solution. The modified magnetite Nano-Particles (NPs) were examined by using several techniques, including X-Ray Diffraction (XRD), Fourier Transform Infra-Red (FTIR) spectroscopy, Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Elemental Analysis (EA), Vibrating Sample Magnetometry (VSM), and Thermo-Gravimetric Analysis (TGA). The effects of different parameters, such as pH, contact time, adsorption isotherm, reaction temperature, ultrasonic desorption, and reusability was evaluated. The results demonstrated that the best adsorption of diazinon on the modified magnetite nano-sorbent occurred at 20°C at the optimum pH of 6. The initial concentration and adsorbent dosage were 100 mg L−1 and 0.01 g, respectively. The kinetic study showed that the best time for the pesticide sorption was 2 min. Also, the Pseudo-Second-Order (PSO) model employed fitted the adsorption kinetics well, thus exhibiting high correlation coefficients. Diazinon adsorption capacity was found to be 34 mg g−1. The equilibrium data of diazinon modified by the magnetite nano-sorbent were suitably shown by Langmuir, Freundlich, Redlich-Peterson, and Temkin models. The data fitted well to Langmuir equation, thus indicating the monolayer adsorption. The reusability experiments revealed excellent removal capabilities of at least 10 times. The results demonstrated that the proposed method had the significant advantages of simplicity and efficiency for diazinon determination from real water samples. [ABSTRACT FROM AUTHOR]

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A method for the determination of 14 pesticide residues in tea was developed by QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) pretreatment combined with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The tea samples were extracted with acetonitrile (with 1% acetic acid), purified using QuEChERS purification columns and then analyzed by UPLC-MS/MS. The effects of four purification columns on tea extracts and the recoveries of pesticide residues were compared. The column with better purification effect and recovery was selected to further investigate the matrix effect, linear relationship, and recovery of the method. The results showed that the detection limit of the method was 0.001~2.000 μg/L, and the limit of quantification was 0.003~5.000 μg/L. Reliable linear relationship within the corresponding concentration range were observed for 14 pesticides, with coefficient of determination between 0.9926 and 0.9989. The average recoveries were 71.2%~117.4% at the spiking levels of 100, 500, and 800 μg/kg with RSDs at the range of 1.1%~14.2%. This method showed its advantages of simple and fast operation, sensitivity and recovery rate, meeting the requirements for determination of multi pesticide residues in tea.

The widespread application of organophosphorus pesticides (OPs) has inflicted significant damage on human well-being and food security. Hence, it is imperative to develop a friendly and accessible biosensor for the detection of OPs. Herein, apple polysaccharide (AP) stabilized palladium nanoparticles (AP-Pd n NPs) with a particle size of 2.75–5.95 nm were prepared using AP as a stabilizer and reducing agent. AP-Pd 30 NPs exhibited good peroxidase-like activity and effectively decomposed H 2 O 2 to ·OH, which catalyzed the 3,3′,5,5′-tetramethylbenzidine system to become blue. The catalytic kinetics of AP-Pd 30 NPs conformed to the typical Michelis-Menten equation. Furthermore, OPs directly inhibited the peroxidase-like activity of AP-Pd 30 NPs. Thus, a highly effective colorimetric biosensor was developed for the detection of OPs. The detection range of the biosensor was 0.050 μg/L - 200 mg/L, and the limit of detection was extremely low to 0.010 μg/L. Compared with other nanomaterials, the detection platform based on AP-Pd 30 NPs can effectively detect organophosphorus pesticides without coupling natural enzymes；this method is more economical and practical. Therefore, this established method explores good perspective for the detection of OPs. [Display omitted] • Apple polysaccharide stabilized palladium nanoparticles (AP-Pd n NPs) were prepared for the first time. • AP-Pd n NPs were spherical with a particle size of 2.75–5.95 nm and had good stability in solution. • AP-Pd n NPs exhibited an excellent peroxidase-like activity. • A new and simple method using AP-Pd 30 NPs was developed for sensitive colorimetric detection of organophosphorus pesticides. [ABSTRACT FROM AUTHOR]

Profenofos (PFF) is a commonly used organophosphorus insecticide that requires strict monitoring due to its potential environmental, ecological, and human health risks originating from residues in soil and water systems, as well as accumulation in crops. In this study, a novel monoclonal antibody (mAb) specific to PFF was prepared for the first time and the recognition mechanism was investigated through molecular simulation. Subsequently, a mAb-based colloidal gold immunochromatographic assay (GICA) was developed for the rapid screening of PFF in fruit and vegetable samples. The mAb exhibited an IC 50 value of 12.9 ng/mL, and limit of detection (LOD) of 4.6 ng/mL, respectively in indirect competitive immunosorbent enzyme-linked immunosorbent assay (ic-ELISA). After optimization, the developed GICA exhibited a visual limit of detection (vLOD) of 20 ng/mL and a quantitative of detection (qLOD) of 5.2 ng/mL, with a linear range from 10.0 to 83.8 ng/mL. Good correlation was observed between the results of GICA and standard Gas Chromatography-Tandem Mass Spectrometry (GC-MS/MS) in matrix and recovery test. The developed GICA can be used for rapid sample detection within 15 min, which is an excellent tool for screening PFF in foods and environmental samples. [Display omitted] • Monoclonal antibody with good sensitivity and specificity to profenofos was produced. • Computer simulation was performed to study the interaction between antibody and profenofos. • Rapid and simple colloidal gold immunochromatographic assay was developed for visual detection of profenofos. [ABSTRACT FROM AUTHOR]

In this work, a flexible electrochemical sensor was developed for the detection of organophosphorus pesticides (OPs). To fabricate the sensor, graphene was generated in situ by laser-induced graphene (LIG) technology on a flexible substrate of polyimide (PI) film to form a three-electrode array, and pralidoxime (PAM) chloride was used as the probe molecule. CeO2 was used to modify the working electrode to improve the sensitivity of the sensor because of its electrocatalytic effect on the oxidation of PAM, and the Ag/AgCl reference electrode was prepared by the drop coating method. The effects of the laser power, laser scanning speed, and CeO2 modification on the electrochemical properties of the sensor were studied in detail. The results prove that the sensor has good repeatability, stability, and anti-interference ability, and it shows an excellent linear response in the chlorpyrifos concentration range from 1.4 × 10−8 M to 1.12 × 10−7 M with the detection limit of 7.01 × 10−10 M.

In the present study, a molecularly imprinted solid-phase extraction (MISPE) technique coupled with high-performance liquid chromatography was applied for selective extraction and recognition of fenthion insecticide in the biological sample. The nanoparticles of fenthion imprinted polymer were prepared by precipitation polymerisation using methacrylic acid (MAA) as functional monomer, ethylene glycol dimethacrylate (EGDMA) as cross-linker, and 70 mL of chloroform. Morphological and structural characterisation was achieved by scanning electron microscopy and infrared spectrometry. The optimisation of parameters being effective on extraction yield was carried out by employing the central composite design (CCD). The empirical models were developed to link the output response and input variables and the proposed models were tested for significance through analysis of variance (ANOVA). The optimum conditions leading to the maximum efficiency of MISPE were sorbent mass of 8.61 mg, sample pH 4.93, sample flow rate of 2.07 mLmin−1, as well as 1.94 mL of methanol/acetic acid (95.7:4.3, v/v) at the flow rate of 1 mLmin−1 as elution solvent. Under the optimised conditions, a linear range of 20–120 μgL−1 was obtained and the limit of detection was found to be 4.58 μgL−1. Analysis of spiked urine samples demonstrated the satisfactory efficiency of the designed protocol ranging from 92.69 to 95.64% and the relative standard deviation (RSD) was calculated to be lower than 3.75%. [ABSTRACT FROM AUTHOR]

Plasmonic nanoparticles can provide great utility for the construction of advanced optical and electrical sensors. Herein, we present a versatile sensing strategy that can perform triple-mode detection of organophosphorus pesticides (OPPs) based on carbon dots (CDs)-participated silver deposition on gold nanoparticles (AuNPs). Simply, a hybrid system composed of AuNPs, CDs, and silver ions in phosphate-buffered saline (AuNPs/Ag+/CDs) is designed, and alkaline phosphatase (ALP) is used to catalytically produce l-ascorbic acid, which reduces silver ions to metallic silver on the surface of AuNPs. OPPs can simultaneously modulate triple optical signals, including light absorption, fluorescence, and Rayleigh scattering of the AuNPs/Ag+/CDs hybrid, by inhibiting the activity of ALP, and thus colorimetry, fluorescence, and resonance Rayleigh scattering methods for OPPs are established. Meanwhile, the mechanism of spectral change involved in the three optical signals is investigated in detail. In addition, the proposed detection system is used for the determination of OPPs in vegetables with satisfactory results. The nanohybrid-platform-integrated triple-signal readout provides not only approaches for OPPs detection but also insight for the development of optical sensors. [ABSTRACT FROM AUTHOR]

Chlorpyrifos pesticide is widely used to control harmful pesticides and insecticides. This well-known organophosphorus pesticidepossesses toxicity to its users. In the current study, we have evaluated the toxic effect of repeated exposure tochlorpyrifos in Wistar rats. The toxic effect of the chlorpyrifos at different dose levels i.e. low dose (10 mg/kg b.wt.), intermediate dose (30 mg/kg b.wt.), and high dose groups (60 mg/kg b.wt.) have been investigated. Various biochemical parameterssuch as glucose, total protein, ALT, AST, ALP, AChE, urea, creatinine, sodium, potassium, and chloride have been assessed. No toxic sign was observed in the treated group animals when compared with the control group animals. Under the condition of this study, the high dose animal body weight was found slightly reduce as compared with the control and other treated animal group. The study showed the various changes in the biochemical parameters in rats after repeated exposure to chlorpyrifos by the oral route. Under the condition of this study, the repeated oral administration of Chlorpyrifos in Wistar rats at the dose level of 60 mg/kg. b.wt. for 28 consecutive days, showed an alteration in the biochemical enzyme like ALT, AST, and AChe when compared with the control group respectively. The level of ALT and AST were found to increase and the level of AChe was found to decrease as compared with the control, low dose, and intermediate-dose group animals. Other parameters which were estimated, were found comparative with the control group. The use of chlorpyrifos in domestic and agricultural platforms provides a great help in minimizing the damages caused by insects, but on the other hand, its long-term exposure is harmful tothe animal as well as the human population. [ABSTRACT FROM AUTHOR]

Accurate determination of pesticide residues is crucial for food safety. A self-calibration method was developed for dual-signal "naked-eye" detection of organophosphorus pesticides (OPs) using bifunctional gold nanozymes (AuNEs). OPs inhibit the cascade reaction of acetylcholinesterase/choline oxidase (AChE/CHO) to reduce hydrogen peroxide (H 2 O 2 ) production, which affects the AuNE-catalyzed color reaction and quenches the fluorescence of AuNEs with the assistance of Fe 2+ . The multi-enzyme cascade system can be integrated into hydrogel sheets for smartphone-assisted digital, quantitative, and onsite detection of OPs in real food samples by analyzing the linear changes in colorimetric and fluorometric signals, which closely match liquid chromatography-mass spectrometry (LC-MS) results. This method displays a lowest 'naked-eye' detection concentration of 7 ppb, a wide linear range (0-2000 ng/mL), and particularly the advantage of anti-interference via self-calibration when one of the signals is abnormal., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Constructing stable, portable sensors and revealing their mechanisms is challenging. Ion metal-organic frameworks (IMOFs) are poised to serve as highly effective electrochemical sensors for detecting organophosphorus pesticides (OPs), leveraging their unique charge properties. In this work, an amino-modified IMOF was constructed and combined with near-field communication (NFC) technology to develop a portable, touchless, and battery-free electrochemical biosensor NH 2 -IMOF@CS@AChE . -NH 2 in NH 2 -IMOF gives the framework a higher electropositivity compared to IMOF , enhancing the electrostatic attraction with acetylcholinesterase (AChE), which is beneficial for immobilizing AChE. Furthermore, the uncoordinated O atoms and the (CH 3 ) 2 NH 2 + groups in NH 2 -IMOF help to form stronger bonds with AChE through hydrogen bonds. The results showed a wide linear response range of 1 × 10 -15 to 1 × 10 -9 M and a low detection limit of 1.24 × 10 -13 M for glyphosate (Gly) in the practical detection of OPs. Additionally, electrochemical biosensor arrays were constructed to effectively identify and distinguish multiple OPs on the basis of their unique differential pulse voltammetry (DPV) electrochemical signals. This work provides a simple and effective solution for on-site OP analysis and can be widely applied in food safety and water quality monitoring.

In the present study, four materials based on boron nitride nanotubes—namely pristine BNNT, C-doped BNNT, tetrapeptide/BNNT, and tetrapeptide/C-doped BNNT—were examined to evaluate adsorption of the organophosphorus pesticides chlorpyrifos and fenitrothion. Through a quantum chemical approach to the molecular and electronic structures, the impacts of C doping and tetrapeptide modification on boron nitride nanotubes are clarified. The results reveal that the tetrapeptide decoration does have the potential for differential sensing of chlorpyrifos and fenitrothion, but the improvement in the adsorption characteristics is slightly inferior to that of the C doping method. Nanosensors, such as C-doped BNNT and tetrapeptide/C-doped BNNT, are used to monitor chlorpyrifos and fenitrothion in solution phase, respectively. This quantum chemistry investigation has paved the way for the design of differential sensing devices for organophosphorus pesticides. [ABSTRACT FROM AUTHOR]

In this work, we reported a rapid and sensitive fluorescence assay in homogenous solution for detecting organophosphorus pesticides by using tetramethylrhodamine (TAMRA)-labeled aptamer and its complementary DNA (cDNA) with extended guanine (G) bases. The hybridization of cDNA and aptamer drew TAMRA close to repeated G bases, then the fluorescence of TAMRA was quenched by G bases due to the photoinduced electron transfer (PET). Upon introducing the pesticide target, the aptamer bound to pesticide instead of cDNA because of the competition between pesticide and cDNA. Thus, the TAMRA departed from G bases, resulting in fluorescence recovery of TAMRA. Under optimal conditions, the limits of detection for phorate, profenofos, isocarbophos, and omethoate were 0.333, 0.167, 0.267, and 0.333 µg/L, respectively. The method was also used in the analysis of profenofos in vegetables. Our fluorescence design was simple, rapid, and highly sensitive, which provided a means for monitoring the safety of agricultural products. [ABSTRACT FROM AUTHOR]

Organophosphorus pesticides are currently extensively applied on the control of agricultural and forestry pests. The number of poisonings and deaths caused by organophosphorus pesticides are increasing year by year. Because of the complex matrix, numerous interfering substances, and low poison content, pretreatment methods are crucial for the detection and analysis of such cases. As an adsorbent used for pretreatment, magnetic nanoparticles have the advantages of simple preparation, convenient modification, superparamagnetism, and hydrophilicity. Microextraction can be performed with small amount of magnetic nanoparticles in a short time, and the target substances can be separated with an external magnetic field. In this paper, the latest research achievements are reviewed. Based on the introduced characteristics and preparation methods of magnetic nanoparticles, this paper outlines the applications of different functionalized magnetic nanoparticles for the pretreatment of organophosphorus pesticides and predict the potential research prospects.

One of the greatest challenges for the future is represented by the conservation of global agricultural production: it is necessary to implement early monitoring of the health conditions of crops through innovative technologies that allow a sustainable development. To reach this goal, the development of portable biosensors might represent a robust strategy for monitoring agricultural sites in agreement with the requirement of precision agriculture. In this work, an electrochemical inhibition biosensor has been engineered onto a glove to quantify organophosphorus pesticides directly on fruits peels. The biosensor was obtained through modification with a bio-hybrid probe which included Prussian blue, Carbon black and butyrylcholinesterase enzyme. The detection concept is based on the inhibition of the enzyme in presence of the pesticide, namely dichlorvos. The experimental setup has been characterized and the ultimate on-glove configuration has been applied towards the detection of dichlorvos directly on fruit peels, namely apples and oranges. The only task required for the end-user was to scrub the surface of the fruit with the strip and performing the electrochemical reading. The portable system was characterized by a low detection limit in the nanomolar range (high ppt) and a satisfactory repeatability lower than 10 %. It represents the starting point towards the design of on-glove biosensors in many fields of application, including the precision agriculture. [Display omitted] • An enzymatic-based electrochemical biosensor has been integrated onto a glove. • Glove-based biosensors offer a valuable tool for decentralized analysis. • Pesticides are directly sampled and analyzed onto fruit peels. • The detection limit for dichlorvos is lower than the limit established by EU regulations. • Portable and miniaturized application for the use of non-specialists. [ABSTRACT FROM AUTHOR]

Rapid and precise detection of organophosphorus pesticides (OPs) is of great importance for life health. Herein, a new sensing platform is developed through a dual signal amplification approach for sensitive quantification of OPs, with a bimetallic metal organic framework (UiO-66(Zr/Fe)-NH 2) as peroxide-like nanozyme and fluorescent indicator. In the presence of thiocholine (TCh), the hydrolyzate of acetylthiocholine iodide catalyzed by acetylcholinesterase, the catalytic oxidization of o-phenylenediamine by UiO-66(Fe/Zr)-NH 2 to strong fluorescent 2,3-diaminophenazine (λ em 555 nm) is significantly inhibited. OPs-triggered acetylcholinesterase inactivation enables the renaturation of UiO-66(Fe/Zr)-NH 2. Interestingly, the introduction of 1,4-dioxane further boosts the amplification of fluorescence signals. By virtue of the recovered fluorescence at 555 nm and MOF fluorescence (λ em 446 nm), the dual signal amplification-based ratiometric fluorescent platform is successfully employed for the selective recognition and sensitive detection of OPs. This work is expected to provide a facile and sensitive method for accurate OPs assay, and make a positive contribution to food safety. [Display omitted] • UiO-66(Zr/Fe)-NH 2 acts as fluorescence indicator and bionic nanozyme. • Signal enhancement upon addition of 1,4-dioxane improves detection sensitivity. • This sensing platform exhibits favorable selectivity and sensitivity for OPs assay. • Sensitive detection of OPs in food samples is effectively achieved by the platform. [ABSTRACT FROM AUTHOR]

Organophosphorus pesticides (OPPs) present in tea infusions pose a serious threat to human health. In this study, a sensitive method for the determination of OPPs was developed based on a direct-immersion solid-phase microextraction (DI-SPME) probe. By fine adjustment of the ratio and one-step polymerization of dihydroxy-functionalized zirconium-based metal-organic framework UiO-66-(OH) 2 and divinylbenzene- N -vinyl pyrrolidone (DVB-NVP) microspheres, the DVB-NVP@ UiO-66-(OH) 2 (D-N@U) composite with an optimal hydrophilic-lipophilic balance (HLB) was achieved. Furthermore, D-N@U was adhesively bonded to stainless-steel wires to fabricate a DI-SPME probe. OPPs, especially those with nonpolar properties characterized by a high octanol-water partition coefficient (log K OW), were selectively and efficiently enriched on the D-N@U-coated DI-SPME probe from tea infusions. Coupled with a gas chromatography-flame photometric detector, the as-fabricated D-N@U-coated DI-SPME probe achieved good performance for OPPs analysis with a wide linear dynamic range of 0.10–500.00 μg/L and low detection limits of 1.96–6.69 ng/L. Moreover, in spiked samples, the recoveries and relative standard deviations were in the ranges of 73.12%–101.20 % and 1.03%–6.56 %, respectively. Owing to its simple operation, high extraction efficiency, and high sensitivity, this approach has great potential for the rapid determination of multiple pesticide trace-level residues in food. Fig. 1. Schematic of the preparation and application of D-N@U-coated DI-SPME for OPPs. [Display omitted] • First composite of DVB-NVP and UiO-66-(OH) 2 for rapid analysis of trace OPPs. • The D-N@U-coated probe was optimized to achieve the best HLB in tea infusions. • Selective DI-SPME of a range of nonpolar OPPs with D-N@U-coated probe. • Higher sensitivity and extraction efficiency compared to commercial SPME probes. [ABSTRACT FROM AUTHOR]

Bu çalışmada, insan serum albümin nanopartiküller (HSA NP) ve elektrobiriktirilmiş yüzey aktif polisetiltrimetil amonyum bromür p(CTAB) film kaplı grafit elektrotlar (PGE) tehlikeli bir çevresel kirletici olan metil paratiyonun (MP) hassas ve seçici tespiti için elektrokimyasal sensör olarak kullanıldı. Elde edilen HSA NP/p(CTAB)/PGE mikroskopik ve elektrokimyasal olarak karakterize edildi. Diferansiyel puls voltametri (DPV) tekniği ile MP için elde edilen doğrusal çalışma aralığı 0,01-0,1 µM ve gözlenebilme sınırı ise 6 nM olarak tespit edildi. MP tespiti için geliştirilen enzim kullanımı gerektirmeyen ve basit hazırlama stratejisine sahip HSA NP/p(CTAB) tabanlı elektrokimyasal sensör, çevre koruma ve gıda güvenliği açısından izleme sürecini de basitleştirme potansiyeline sahiptir.

Environmental protection has always been a hot topic, and the irresponsible use of organophosphorus pesticides has caused severe damage to the environment. The advantages of immunoassays for the detection of pesticides has allowed more researchers to develop and improve methods, in particular the performance of the assay, with few researchers considering the environmental impact of the method. The 12 principles of Green Analytical Chemistry (GAC) represent a guide for the development of environmentally friendly analytical methods. Eco-Scale and Green Analytical Procedure Index (GAPI) are assessment metrics based on GAC, where GAPI is used to assess the green characteristics of the entire analytical method from sample collection to final determination, and the difference in color gives an evaluation of the environmental impact involved in each step. In this paper, we modified GAPI to make it more suitable for the assessment of immunoassays, and combined it with Eco-Scale penalty rules to give scores for the sample preparation and assay steps, and finally to obtain the assessment results intuitively for the method so that researchers and users can choose. We used this tool for the immunoassay evaluation of chlorpyrifos in vegetables, and the method showed good reliability and consistency with scoring. • The modified GAPI is suitable for the assessment of immunoassays. • The assessment results were used for the immunoassay evaluation of chlorpyrifos. • This method showed good reliability and consistency with scoring. [ABSTRACT FROM AUTHOR]