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Analytica Chimica Acta Nov 2023The residues of pesticides and antibiotics have always been a major concern in agriculture and food safety. In order to provide a new method for the rapid detection of...
Sensitive fluorescent detection of phosmet and chlortetracycline in animal-derived food samples based on a water-stable Cd(II) chain-based zwitterionic metal-organic framework.
The residues of pesticides and antibiotics have always been a major concern in agriculture and food safety. In order to provide a new method for the rapid detection of organophosphorus pesticides and antibiotics, a novel Cd(II) chain-based zwitterionic metal-organic framework MOF 1 with high sensitivity fluorescence sensing performance was successfully synthesized. A series of researches showed that the water- and pH-stable bifunctional MOF 1 has a great ability to detect phosmet (PSM) and chlortetracycline (CTC) in water through fluorescence quenching effect, with high detection sensitivity, low detection limits (0.0124 μM and 0.0131 μM), short response time (40 s) and reusability. Practical application results revealed that MOF 1 could detect PSM and CTC in milk, beef, chicken and egg samples, with satisfactory recoveries (95.2%-103.7%). As a novel fluorescence probe, MOF 1, is known the first case that can detect PSM in animal-derived samples, and the first dual-function material capable of detecting PSM and CTC. Mechanism studies displayed that competitive absorption and photoinduced electron transfer clearly authenticate the high quenching performance of the material.
Topics: Animals; Cattle; Chlortetracycline; Metal-Organic Frameworks; Phosmet; Cadmium; Water; Organophosphorus Compounds; Pesticides; Anti-Bacterial Agents
PubMed: 37858547
DOI: 10.1016/j.aca.2023.341850 -
Environmental Science. Processes &... Dec 2023Phosmet is an organophosphorus insecticide widely used in agriculture to control a range of insects; recently, it was banned by the European Union in 2022 due to its...
Phosmet is an organophosphorus insecticide widely used in agriculture to control a range of insects; recently, it was banned by the European Union in 2022 due to its harmful effects. However, its environmental degradation and fate have not yet been evident. Thus, phosmet oxidation by HO˙ radicals was theoretically studied in this work using the DFT approach at the M06-2X/6-311++G(3df,3pd)//M06-2X/6-31+G(d,p) level of theory. Three different mechanisms were considered, including formal hydrogen transfer (FHT), radical adduct formation (RAF), and single electron transfer (SET). The mechanisms, kinetics, and lifetime were studied in the gas and aqueous phases, in addition to its ecotoxicity evaluation. The results show that FHT reactions were dominant in the gas phase, while RAF was more favourable in the aqueous phase at 298 K, while SET was negligible. The branching ratio indicated that H-abstractions at the methyl and the methylene groups were the most predominant, while the most favourable HO˙-addition was observed at the phosphorus atom of the dithiophosphate group. The overall rate constant values varied from 1.2 × 10 (at 283 K) to 1.40 × 10 M s (at 323 K) in the aqueous phase and from 6.29 × 10 (at 253 K) to 1.32 × 10 M s (at 323 K) in the gas phase. The atmospheric lifetime of phosmet is about 6 hours at 287 K, while it can persist from a few seconds to several years depending on the temperature and [HO˙] concentration in the aqueous environment. The QSAR-based ecotoxicity evaluation indicates that phosmet and its degradation products are all dangerous to aquatic organisms, although the products are less toxic than phosmet. However, they are generally developmental toxicants and mutagenicity-negative compounds.
Topics: Insecticides; Phosmet; Water; Organophosphorus Compounds; Oxidation-Reduction; Kinetics; Models, Theoretical; Hydroxyl Radical
PubMed: 37850503
DOI: 10.1039/d3em00325f -
Ophthalmic & Physiological Optics : the... Jan 2024This study used three-dimensional (3D) modelling to investigate scleral profiles in myopic eyes and compare them with emmetropic eyes. (Observational Study)
Observational Study
PURPOSE
This study used three-dimensional (3D) modelling to investigate scleral profiles in myopic eyes and compare them with emmetropic eyes.
METHODS
In this prospective observational study, the eyes of 151 participants were analysed using the corneoscleral profile module (CSP) of the Pentacam HR. Non-rotationally symmetrical ellipsoids were fitted to the anterior scleral sagittal height. Three radii were analysed, namely the nasal-temporal (Rx), superior-inferior (Ry) and anterior-posterior (Rz) orientations. Additionally, the area index (AI) and aspherical parameters (Qxy, Qxz and Qyz) of the anterior sclera-fitted ellipsoid (ASFE) were quantified.
RESULTS
The findings showed an increase in Rx (-0.349 mm/D), Ry (-0.373 mm/D), Rz (-1.232 mm/D) and AI (-36.165 mm /D) with increasing myopia. From emmetropia to high myopia, the vertical and horizontal planes of the anterior sclera became increasingly prolate (emmetropia, Qxz: 0.02, Qyz: 0.01; low myopia, Qxz: -0.28, Qyz: -0.28; high myopia, Qxz: -0.41, Qyz: -0.43). There were no significant differences in the coronal plane across the three groups (H = 2.65, p = 0.27). The anterior scleral shape of high myopes in the horizontal and vertical planes was more prolate than that of emmetropes and low myopes (Qxz, high myopes vs. low myopes: p = 0.03, high myopes vs. emmetropes: p < 0.001; Qyz, high myopes vs. low myopes: p = 0.04, high myopes vs. emmetropes: p < 0.001).
CONCLUSIONS
As the degree of myopia increased, non-uniform anterior scleral enlargement was observed. These findings provide a better understanding of the anterior segment with varying degrees of myopia.
Topics: Humans; Sclera; Phosmet; Myopia; Emmetropia; Prospective Studies
PubMed: 37811684
DOI: 10.1111/opo.13235 -
Journal of Materials Chemistry. B Oct 2023Conventional nanozyme-based pesticide detection often requires the assistance of acetylcholinesterase. In this work, a CuCeTA nanozyme was successfully designed for the...
Conventional nanozyme-based pesticide detection often requires the assistance of acetylcholinesterase. In this work, a CuCeTA nanozyme was successfully designed for the direct colorimetric detection of glyphosate. Direct detection can effectively avoid the problems caused by cascading with natural enzymes such as acetylcholinesterase. By assembling tannic acid, copper sulfate pentahydrate and cerium(III) nitrate hexahydrate, CuCeTA nanoflowers were prepared. The obtained CuCeTA possessed excellent peroxidase-like activity that could catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to blue oxidized TMB in the presence of hydrogen peroxide. Glyphosate could effectively inhibit the peroxidase-like activity of CuCeTA while other pesticides (fenthion, chlorpyrifos, profenofos, phosmet, bromoxynil and dichlorophen) did not show significant inhibitory effects on the catalytic activity of CuCeTA. In this way, CuCeTA could be used for the colorimetric detection of glyphosate with a low detection limit of 0.025 ppm. Combined with a smartphone and imageJ software, a glyphosate test paper was designed with a detection limit of 3.09 ppm. Fourier transform infrared spectroscopy demonstrated that glyphosate and CuCeTA might be bound by coordination, which could affect the catalytic activity of CuCeTA. Our CuCeTA-based nanozyme system exhibited unique selectivity and sensitivity for glyphosate detection and this work may provide a new strategy for rapid and convenient detection of pesticides.
Topics: Peroxidase; Acetylcholinesterase; Colorimetry; Peroxidases; Coloring Agents; Pesticides; Glyphosate
PubMed: 37750214
DOI: 10.1039/d3tb01455j -
The International Journal of... Oct 2022Abnormal Left ventricular mass (LVM) prognosticates adverse cardiovascular events. Conventionally, LVM measured by echo assumes a prolate ellipsoid (PE) shape; however,...
Abnormal Left ventricular mass (LVM) prognosticates adverse cardiovascular events. Conventionally, LVM measured by echo assumes a prolate ellipsoid (PE) shape; however, it poorly correlates with reference standard of cardiac magnetic resonance imaging (CMR) derived LVM. PE model assumes LVL = 2 × LVID. We developed a new echo LVM formula based on LV length and tested for accuracy against CMR. A retrospective study of consecutive patients with an echocardiogram and CMR within 3 months. Derivation (n = 170) and validation cohorts (n = 54) were used to test the new formula. Following analysis of correlation of interventricular septum (IVS), LV internal dimension (LVID), posterior wall (PW) and LVL between echo and CMR, a novel paraboloid-shape linear regression (PLR) model was derived. LVM by both models were compared to CMR. Poor correlation observed between actual and assumed LVL (0.52 with CMR; 0.44 with echo). Strong correlation was noted between echo and CMR measured LVL, LVID, IVS (r > 0.80) and a moderate correlation with PW (r = 0.62). Strong correlation of LVL was harnessed to develop PLR model, which significantly decreased paired error in derivation cohort (from 64 ± 42 to 22 ± 21 gm) and validation cohort (from 63 ± 46 to 25 ± 18 gm). Furthermore, it demonstrates significant reduction in absolute, relative errors and variability along with superior correlation in both cohorts. Between echo and CMR, LVL demonstrates one of the best correlation among LV dimensions. The assumption, LVL = 2 × LVID appears inaccurate. PLR model incorporates LVL and significantly improves accuracy, reduces variability of LVM.
Topics: Humans; Retrospective Studies; Predictive Value of Tests; Echocardiography; Ventricular Septum; Linear Models; Phosmet
PubMed: 37726463
DOI: 10.1007/s10554-022-02627-7 -
Foods (Basel, Switzerland) Sep 2023In modern agricultural practices, organophosphorus pesticides or insecticides (OPs) are regularly used to restrain pests. Their limits are closely monitored since their...
A Multi-Enzyme Cascade Response for the Colorimetric Recognition of Organophosphorus Pesticides Utilizing Core-Shell Pd@Pt Nanoparticles with High Peroxidase-like Activity.
In modern agricultural practices, organophosphorus pesticides or insecticides (OPs) are regularly used to restrain pests. Their limits are closely monitored since their residual hinders the capability of acetylcholinesterase (AChE) and brings out a threatening accumulation of the neurotransmitter acetylcholine (ACh), which affects human well-being. Therefore, spotting OPs in food and the environment is compulsory to prevent human health. Several techniques are available to identify OPs but encounter shortcomings like time-consuming, operating costs, and slow results achievement, which calls for further solutions. Herein, we present a rapid colorimetric sensor for quantifying OPs in foods using TMB as a substrate, a multi-enzyme cascade system, and the synergistic property of core-shell Palladinum@Platinum (Pd@Pt) nanoparticles. The multi-enzyme cascade response framework is a straightforward and effective strategy for OPs recognition and can resolve the previously mentioned concerns. Numerous OPs, including Carbofuran, Malathion, Parathion, Phoxim, Rojor, and Phosmet, were successfully quantified at different concentrations. The cascade method established using Pd@Pt had a simple and easy operation, a lower detection limit range of (1-2.5 ng/mL), and a short detection time of about 50 min. With an R value of over 0.93, OPs showed a linear range of 10-200 ng/mL, portraying its achievement in quantifying pesticide residue. Lastly, the approach was utilized in food samples and recovered more than 80% of the residual OPs.
PubMed: 37685251
DOI: 10.3390/foods12173319 -
Micromachines Mar 2023Here, a molecular imprinting technique was employed to create an SPR-based nanosensor for the selective and sensitive detection of organophosphate-based coumaphos, a...
Here, a molecular imprinting technique was employed to create an SPR-based nanosensor for the selective and sensitive detection of organophosphate-based coumaphos, a toxic insecticide/veterinary drug often used. To achieve this, UV polymerization was used to create polymeric nanofilms using -methacryloyl-l-cysteine methyl ester, ethylene glycol dimethacrylate, and 2-hydroxyethyl methacrylate, which are functional monomers, cross-linkers, and hydrophilicity enabling agents, respectively. Several methods, including scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle (CA) analyses, were used to characterize the nanofilms. Using coumaphos-imprinted SPR (CIP-SPR) and non-imprinted SPR (NIP-SPR) nanosensor chips, the kinetic evaluations of coumaphos sensing were investigated. The created CIP-SPR nanosensor demonstrated high selectivity to the coumaphos molecule compared to similar competitor molecules, including diazinon, pirimiphos-methyl, pyridaphenthion, phosalone, -2,4(dimethylphenyl) formamide, 2,4-dimethylaniline, dimethoate, and phosmet. Additionally, there is a magnificent linear relationship for the concentration range of 0.1-250 ppb, with a low limit of detection (LOD) and limit of quantification (LOQ) of 0.001 and 0.003 ppb, respectively, and a high imprinting factor (I.F.4.4) for coumaphos. The Langmuir adsorption model is the best appropriate thermodynamic approach for the nanosensor. Intraday trials were performed three times with five repetitions to statistically evaluate the CIP-SPR nanosensor's reusability. Reusability investigations for the two weeks of interday analyses also indicated the three-dimensional stability of the CIP-SPR nanosensor. The remarkable reusability and reproducibility of the procedure are indicated by an RSD% result of less than 1.5. Therefore, it has been determined that the generated CIP-SPR nanosensors are highly selective, rapidly responsive, simple to use, reusable, and sensitive for coumaphos detection in an aqueous solution. An amino acid, which was used to detect coumaphos, included a CIP-SPR nanosensor manufactured without complicated coupling methods and labelling processes. Liquid chromatography with tandem mass spectrometry (LC/MS-MS) studies was performed for the validation studies of the SPR.
PubMed: 37420940
DOI: 10.3390/mi14040707 -
Biosensors & Bioelectronics Oct 2023Conventional rapid detection methods are difficult to identify or distinguish various pesticide residues at the same time. And sensor arrays are also limited by the...
Conventional rapid detection methods are difficult to identify or distinguish various pesticide residues at the same time. And sensor arrays are also limited by the complexity of preparing multiple receptors and high cost. To address this challenge, a single material with multiple properties is considered. Herein, we first found that different categories of pesticides have diverse regulatory behaviors on the multiple catalytic activities of Asp-Cu nanozyme. Thus, a three-channel sensor array based on the laccase-like, peroxidase-like, and superoxide dismutase-like activities of Asp-Cu nanozyme was constructed and successfully used for the discrimination of eight kinds of pesticides (glyphosate, phosmet, isocarbophos, carbaryl, pentachloronitrobenzene, metsulfuron-methyl, etoxazole, and 2-methyl-4-chlorophenoxyacetic acid). In addition, a concentration-independent model for qualitative identification of pesticides has been established, and 100% correctness was achieved in the recognition of unknown samples. Then, the sensor array also exhibited excellent interference immunity and was reliable for real sample analysis. It provided a reference for pesticide efficient detection and food quality supervision.
Topics: Pesticides; Biosensing Techniques; Pesticide Residues; Peroxidase; Phosmet
PubMed: 37311405
DOI: 10.1016/j.bios.2023.115458 -
Spectrochimica Acta. Part A, Molecular... Nov 2023Pesticide active ingredients (AIs) are often applied with adjuvants to facilitate the stability and functionality of AIs in agricultural practice. The objective of this...
Pesticide active ingredients (AIs) are often applied with adjuvants to facilitate the stability and functionality of AIs in agricultural practice. The objective of this study is to investigate the role of a common non-ionic surfactant, alkylphenol ethoxylate (APEO), on the surface-enhanced Raman spectroscopic (SERS) analysis of pesticides as well as its impact on pesticide persistence on apple surfaces, as a model fresh produce surface. The wetted areas of two AIs (thiabendazole and phosmet) mixed with APEO were determined respectively to correct the unit concentration applied on apple surfaces for a fair comparison. SERS with gold nanoparticle (AuNP) mirror substrates was applied to measure the signal intensity of AIs with and without APEO on apple surfaces after a short-term (45 min) and a long-term (5 days) exposure. The limit of detection (LOD) of thiabendazole and phosmet using this SERS-based method were 0.861 ppm and 2.883 ppm, respectively. The result showed that APEO decreased the SERS signal for non-systemic phosmet, while increased SERS intensity of systemic thiabendazole on apple surfaces after 45 min pesticide exposure. After 5 days, the SERS intensity of thiabendazole with APEO was higher than thiabendazole alone, and there was no significant difference between phosmet with and without APEO. Possible mechanisms were discussed. Furthermore, a 1% sodium bicarbonate (NaHCO) washing method was applied to test the impact of APEO on the persistence of the residues on apple surfaces after short-term and long-term exposures. The results indicated that APEO significantly enhanced the persistence of thiabendazole on plant surfaces after a 5-day exposure, while there was no significant impact on phosmet. The information obtained facilitates a better understanding of the impact of the non-ionic surfactant on SERS analysis of pesticide behavior on and in plants and helps further develop the SERS method for studying complex pesticide formulations in plant systems.
Topics: Pesticides; Malus; Phosmet; Surface-Active Agents; Gold; Thiabendazole; Metal Nanoparticles; Lipoproteins
PubMed: 37270975
DOI: 10.1016/j.saa.2023.122954 -
Journal of Economic Entomology Jun 2023The use of toxic baits has become one of the main methods of management of fruit flies in Brazil. The application of toxic baits may cause side effects on the native...
The use of toxic baits has become one of the main methods of management of fruit flies in Brazil. The application of toxic baits may cause side effects on the native parasitoid Doryctobracon areolatus (Hymenoptera: Braconidae). Based on the results, formulations made from the food attractants 3% Biofruit, 1.5% Ceratrap, 1.25% Flyral, 3% Isca Samaritá, 3% Isca Samaritá Tradicional, and 7% sugarcane molasses associated with the Malathion 1000 EC and the ready-to-use toxic bait Gelsura (containing the active ingredient alpha-cypermethrin) were classified as harmful (class 4) to D. areolatus (mortality > 85% at 96 HAE). In contrast, for toxic baits formulated with insecticide phosmet, the mortality ranged from 38% to 72%, classified as slightly harmful or moderately harmful. However, when phosmet was added to the 3% Samaritá Tradicional bait, the mortality was only 3.9% (class 1-harmless), similar to the toxicity observed for the Success 0.02 CB ready-to-use bait (0.24 g a.i. spinosad/l) (<5% mortality). Although toxic baits were formulated with spinosyn-based insecticides, all toxic bait formulations were classified as harmless or slightly harmful (<50% mortality) to D. areolatus, with the exception of 1.5% Ceratrap + spinetoram and 7% Sugarcane molasses + spinosad (≈ 60% mortality-moderately harmful). In addition, these formulations did not show sublethal effects in reducing the parasitism and emergence rate of the F1 generation of D. areolatus in A. fraterculus larvae. The results serve as a basis for the correct use of toxic food baits without affecting the biological control.
Topics: Animals; Hymenoptera; Phosmet; Tephritidae; Insecticides; Malathion; Drosophila; Edible Grain
PubMed: 37032527
DOI: 10.1093/jee/toad069