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1.
Molecules ; 29(18)2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39339428

RESUMO

The fungicide pyraclostrobin is the main measure used to control apple alternaria blotch in production. To evaluate the potential dietary risks for consumers, the dissipation and terminal residues of pyraclostrobin were investigated using ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS/MS). Pyraclostrobin in apples was extracted by acetonitrile with 2% ammonia and then purified using primary secondary amine (PSA) and graphitized carbon black (GCB). The method showed good linearity within the concentration range of 0.005-0.1 mg L-1, with a coefficient of determination (R2) ≥ 0.9958. The recoveries ranged from 96.0% to 103.8%, with relative standard deviations (RSDs) between 0.8% and 2.3%. The limit of quantification (LOQ) was 0.01 mg kg-1. Pyraclostrobin dispersible oil suspension was applied in 12 apple fields across China according to good agricultural practices (GAPs). In Beijing and Shandong, the dissipation of pyraclostrobin followed first-order kinetic equations, with a half-life of 11 days. The terminal residues ranged from <0.01 to 0.09 mg kg-1. The national estimated daily intake (NEDI) of pyraclostrobin was compared with the acceptable daily intake (ADI), resulting in risk quotient (RQc) of 80.8%. These results suggest that pyraclostrobin poses a low health risk to consumers under GAP conditions and according to recommended dosages.


Assuntos
Fungicidas Industriais , Malus , Estrobilurinas , Espectrometria de Massas em Tandem , Estrobilurinas/análise , Malus/química , Fungicidas Industriais/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Medição de Risco , Carbamatos/análise , Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , Espectrometria de Massa com Cromatografia Líquida
2.
Mikrochim Acta ; 191(9): 540, 2024 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-39150580

RESUMO

For the first time the sensitive determination of carbendatim (CRB) is reported utilizing a well-designed sensing architecture based on vanadium diselenide-multiwalled carbon nanotube (VSMC). FTIR, XRD, FESEM, EDS, and EIS were employed to evaluate the sensor's structural integrity, and the results demonstrated the successful integration of nanomaterials, resulting in a robust and sensitive electrochemical sensor. Cyclic voltammetry (CV) and chronoamperometric (CA) investigations showed that the sensor best performed at pH 8.0 (BRB) with an excellent detection limit of 9.80 nM with a wide linear range of 0.1 to 10.0 µM. A more thermodynamically viable oxidation of CRB was observed at the VSMC/GCE, with a shift of 200 mV in peak potential towards the less positive side compared with the unmodified GCE. In addition, the sensor demonstrated facile heterogeneous electron transfer, favorable anti-fouling traits in the presence of a wide range of interferents, good stability, and reproducible analytical performance. Finally, the developed sensor was validated for real-time quantification of CRB from spiked water, food, and bio-samples, which depicted acceptable recoveries (98.6 to 101.5%) with RSD values between 0.35 and 2.23%. Further, to derive the possible sensing mechanism, the valence orbitals projected density of states (PDOS) for C, H, and N atoms of an isolated CRB molecule, VSe2 + CNT and VSe2 + CNT + CRB were calculated using density functional theory (DFT) calculations. The dominant charge transfer from the valence 2p-orbitals of the C and N atoms of CRB to CNT is responsible for the electrochemical sensing of CRB molecules.


Assuntos
Benzimidazóis , Carbamatos , Técnicas Eletroquímicas , Limite de Detecção , Nanotubos de Carbono , Nanotubos de Carbono/química , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Carbamatos/análise , Carbamatos/química , Benzimidazóis/química , Benzimidazóis/análise , Contaminação de Alimentos/análise , Eletrodos , Poluentes Químicos da Água/análise , Animais
3.
Environ Monit Assess ; 196(9): 783, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39098866

RESUMO

Cucumber (Cucumis sativus L.) is the world's most widely consumed salad vegetable, and it is frequently treated with pesticides to prevent pest and disease outbreaks. Pesticide residues in food commodities impede trade and pose a major health risk. Prior to residue estimation, the QuEChERS approach was validated utilising criteria such as limit of detection, limit of quantitation, linearity, accuracy, and precision. The residues of carbendazim, cypermethrin, ethion, profenofos, quinalphos, and triazophos were examined using a Gas Chromatograph equipped with an Electron Capture Detector or a Flame Photometric Detector and a high-performance liquid chromatography coupled to a photo diode array. The initial deposits of carbendazim, cypermethrin, ethion, profenofos, quinalphos, and triazophos at the prescribed dose were 1.235, 0.407, 0.817, 0.960, 0.628, and 0.985 mg/kg, respectively, with a pre-harvest interval of 5.58-11.30 days. According to the consumer risk evaluation data, the Hazard Quotient is less than one, and the Theoretical Maximum Dietary Intake is less than the Maximum Permissible Intake and Maximum Residue Limit, both of which are considered safe for human consumption at the authorised dose.


Assuntos
Cucumis sativus , Contaminação de Alimentos , Organotiofosfatos , Resíduos de Praguicidas , Cucumis sativus/química , Resíduos de Praguicidas/análise , Contaminação de Alimentos/análise , Medição de Risco , Organotiofosfatos/análise , Triazóis/análise , Carbamatos/análise , Piretrinas/análise , Praguicidas/análise , Humanos , Exposição Dietética/estatística & dados numéricos , Monitoramento Ambiental/métodos , Benzimidazóis , Compostos Organotiofosforados
4.
Food Chem ; 461: 140892, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39178540

RESUMO

Carbendazim (CBZ) insecticides have been widely employed, raising serious concerns about their impacts on human health and the environment. A facile hydrothermal technique was used to prepare a zinc ferrite (ZnFe2O4) combined with porous graphene oxide (PGO) as a nanocomposite for selective CBZ detection. The ZnFe2O4/PGO nanocomposite was then used to modify a glassy carbon electrode (GCE), an affordable platform for CBZ detection. Various spectroscopic techniques were employed to confirm the nanomaterial. The electrochemical properties were further investigated using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). The ZnFe2O4/PGO nanocomposite modified the glassy carbon electrode surface for CBZ detection. A broad linear response range of 0.0039 to 200 µM, high sensitivity (2.184 µAµM-1 cm-2), a low detection limit of 0.0013 µM, outstanding stability, repeatability, and practical applicability are the intriguing qualities of the ZnFe2O4/PGO-modified electrode for CBZ detection.


Assuntos
Benzimidazóis , Carbamatos , Técnicas Eletroquímicas , Compostos Férricos , Grafite , Zinco , Grafite/química , Carbamatos/análise , Carbamatos/química , Compostos Férricos/química , Zinco/química , Técnicas Eletroquímicas/instrumentação , Benzimidazóis/química , Catálise , Eletrodos , Porosidade , Limite de Detecção , Nanocompostos/química
5.
Sci Total Environ ; 948: 174578, 2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-38981541

RESUMO

Pesticide active ingredients are frequently detected in the rivers, creeks, wetlands, estuaries, and marine waters of the Great Barrier Reef (GBR) region and are one of the main contributors to poor water quality. Pesticide concentrations detected in the environment through water quality monitoring programs can be compared against estimates of ecologically "safe" concentrations (i.e., water quality guidelines) to assess the potential hazard and risk posed to aquatic ecosystems. Water quality guidelines are also required to estimate the aquatic risk posed by pesticide mixtures, which is used for the Reef 2050 Water Quality Improvement Plan pesticide target. Seventy-four pesticide active ingredients and their degradates are frequently detected in GBR catchment waterways, however many do not have water quality guidelines in the Australian and New Zealand Guidelines for Fresh and Marine Water Quality. The current study derives ecotoxicity threshold values (ETVs) as unendorsed guideline values for active ingredients in two fungicides (4-hydroxychlorothalonil (fungicide degradate) and carbendazim) and two insecticides (dimethoate and methoxyfenozide) that are commonly detected in GBR catchment waterways. The proposed ETVs have been derived using species sensitivity distributions, as recommended in the Australian and New Zealand nationally endorsed method for deriving water quality guidelines for aquatic ecosystem protection. Four ETVs were derived for each chemical with values that should theoretically protect 99, 95, 90 and 80 % of species (i.e., PC99, PC95, PC90, PC80, respectively). The PC99 and PC95 values for 4-hydroxychlorothalonil, carbendazim, dimethoate and methoxyfenozide were 0.49 µg/L and 4 µg/L, 0.029 µg/L and 0.45 µg/L, 0.11 µg/L and 5.8 µg/L and 0.19 µg/L and 2 µg/L, respectively. The ETVs will be used in an ecological hazard and risk assessment across GBR waterways in part two of this study. The ETVs can also be used to assess potential risk across Australia and internationally where monitoring data are available.


Assuntos
Carbamatos , Monitoramento Ambiental , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Carbamatos/toxicidade , Carbamatos/análise , Água do Mar/química , Água Doce/química , Austrália , Inseticidas/análise , Inseticidas/toxicidade , Fungicidas Industriais/análise , Fungicidas Industriais/toxicidade , Nova Zelândia , Praguicidas/análise , Praguicidas/toxicidade , Medição de Risco , Hidrazinas/toxicidade , Hidrazinas/análise , Benzimidazóis
6.
Food Chem ; 459: 140338, 2024 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38996633

RESUMO

It is highly desirable to develop a low-cost and rapid detection method for trace levels of carbendazim fungicide residues, which would be beneficial for improving human health and mitigating environmental issues. Herein, isolated single tungsten atoms were implanted onto well-organized metal-organic framework (MOF)-derived N-doped carbons to form W-N-C single-site heterojunctions with ultrahigh electrocatalytic activity. The coupling of W-N-C with Cu3(HHTP)2, an electronically conductive MOF with a large surface area and porous structure, exhibited enhanced electrocatalytic performance for the oxidation of carbendazim (CBZ) when they were used for decorating graphene nanoplatelet flexible electrode arrays fabricated via template-assisted scalable filtration. A wide linear range (3.0 nM-50 µM) with an ultra-low detection limit of 0.97 nM and fast response was achieved for CBZ analysis. Moreover, the sensing platform has been utilised to monitor CBZ levels in vegetable samples with satisfactory recovery rates of 97.2-102% and a low relative standard deviation of 1.9%.


Assuntos
Benzimidazóis , Carbamatos , Cobre , Eletrodos , Contaminação de Alimentos , Fungicidas Industriais , Grafite , Estruturas Metalorgânicas , Verduras , Carbamatos/análise , Carbamatos/química , Grafite/química , Verduras/química , Catálise , Estruturas Metalorgânicas/química , Benzimidazóis/química , Benzimidazóis/análise , Cobre/química , Fungicidas Industriais/análise , Fungicidas Industriais/química , Contaminação de Alimentos/análise , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Tungstênio/química , Limite de Detecção , Oxirredução
7.
PLoS One ; 19(7): e0308112, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39083518

RESUMO

The widespread use of organophosphate (OP) and carbamate (CM) pesticides requires efficient and cost-effective detection methods. This study introduces a micro-electrometric method using cricket cholinesterase (ChE) to detect OP and CM residues, providing a rapid and economical alternative to conventional chromatographic techniques. The parameters of the method, including the substrate concentration, incubation temperature, and incubation time, were optimized. By leveraging the sensitivity of cricket ChE to OP and CM inhibition, this approach translates enzyme inhibition into an electrical signal to quantify pesticide levels, achieving an impressive limit of detection (LOD) from 0.036 to 0.086 parts per million (ppm). This method demonstrated reproducibility and stability, making it suitable for field applications and on-site testing across various environmental matrices. This research represents a significant advancement in pesticide residue analysis with potential applications in the development of portable biosensor devices for real-time environmental monitoring and public health protection.


Assuntos
Carbamatos , Colinesterases , Gryllidae , Resíduos de Praguicidas , Carbamatos/análise , Animais , Gryllidae/enzimologia , Colinesterases/metabolismo , Colinesterases/análise , Resíduos de Praguicidas/análise , Organofosfatos/análise , Limite de Detecção , Monitoramento Ambiental/métodos , Monitoramento Ambiental/instrumentação , Técnicas Biossensoriais/métodos , Reprodutibilidade dos Testes
8.
Rapid Commun Mass Spectrom ; 38(19): e9875, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39049483

RESUMO

RATIONALE: 5α-Androstane-3α,17ß-diol (3α,5α-Adiol) is a testosterone-derived neurosteroid and has anxiolytic and analgesic effects via γ-aminobutyric acid type A receptors as with the progesterone-derived neurosteroid, allopregnanolone (AP). Although the psychotropic drug-evoked changes in the brain AP concentration have been intensively studied, those in the brain 3α,5α-Adiol concentration remain poorly understood. One of the causes for this is the limited availability of a validated method for quantifying the brain 3α,5α-Adiol with a sufficient sensitivity and specificity, which is described in this study. METHODS: To enhance the detectability of 3α,5α-Adiol by electrospray ionization-tandem mass spectrometry (ESI-MS/MS), derivatization with 4-dimethylaminobenzoyl azide was employed. The brain sample was purified by solid-phase extraction and the recovered 3α,5α-Adiol and the deuterated internal standard were derivatized, then measured by liquid chromatography (LC)/ESI-MS/MS with selected reaction monitoring. RESULTS: The derivatized 3α,5α-Adiol, i.e., the bis[(4-dimethylamino)phenyl carbamate] derivative, provided the intense doubly-protonated molecule as the precursor ion, then the specific product ion containing the 3α,5α-Adiol-skeleton by collision-induced dissociation. The detectability of 3α,5α-Adiol was eventually increased 1000-fold by derivatization. Separation of the derivatized 3α,5α-Adiol from its stereoisomers and interfering brain components was achieved using a SunShell Biphenyl column with an isopropyl alcohol-containing mobile phase. A good linearity in the sufficient concentration range, acceptable precision and accuracy, and negligible matrix effect were demonstrated by the validation tests. The animal (rat) study using this method revealed that the brain 3α,5α-Adiol levels were unaffected by the administration of fluoxetine (FLX) and clozapine (CLZ), in contrast to the significant increase of the AP levels. CONCLUSION: An LC/ESI-MS/MS method capable of quantifying 3α,5α-Adiol in the rat brain using a 20-mg tissue was developed and validated. The brain levels of 3α,5α-Adiol had an entirely different behavior from those of AP due to FLX and CLZ administration.


Assuntos
Ratos Sprague-Dawley , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Animais , Espectrometria de Massas em Tandem/métodos , Ratos , Espectrometria de Massas por Ionização por Electrospray/métodos , Masculino , Química Encefálica , Cromatografia Líquida/métodos , Limite de Detecção , Androstano-3,17-diol/química , Androstano-3,17-diol/análise , Encéfalo/metabolismo , Reprodutibilidade dos Testes , Carbamatos/química , Carbamatos/análise , Sensibilidade e Especificidade , Cromatografia Líquida de Alta Pressão/métodos
9.
Food Addit Contam Part B Surveill ; 17(3): 230-240, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38835106

RESUMO

This study evaluated the presence of the three pesticides methomyl (MET), carbendazim (CBZ) and chlorpyrifos-ethyl (CPE), as well as the degradation product of CPE (3,5,6-trichloro-2-pyridinol; TCP), in 44 honey samples from all 12 regions of Morocco. With a validated HPLC-UV method occurrence frequencies of 63.6% for MET, 54.5% for CBZ, 95.1% for CPE and 34.1% for TCP were obtained, even at concentrations higher than the maximum residue limits for MET, CPE and TCP. Based on the predominant pesticide, principal component analysis separated sampling regions into three groups. Risk assessment indicated that ingestion of these pesticides, alone or in combination, in honey did not pose a risk to consumers (HQ and HI < 1).


Assuntos
Contaminação de Alimentos , Mel , Resíduos de Praguicidas , Mel/análise , Marrocos , Resíduos de Praguicidas/análise , Contaminação de Alimentos/análise , Humanos , Medição de Risco , Cromatografia Líquida de Alta Pressão , Análise de Componente Principal , Carbamatos/análise , Clorpirifos/análise , Benzimidazóis
10.
Food Chem ; 456: 140063, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38878547

RESUMO

Precisely detecting trace pesticides and their residues in food products is crucial for ensuring food safety. Herein, a high-performance electrochemical sensing platform was developed for the detection of carbendazim (CBZ) using Co,N co-doped hollow carbon nanocage@carbon nanotubes (Co,N-HC@CNTs) obtained from core-shell ZIF-8@ZIF-67 combined with a poly(3,4-ethylenedioxythiophene) (PEDOT) molecularly imprinted polymer (MIP). The Co,N-HC@CNTs exhibited excellent electrocatalytic performance, benefitting from the synergistic effect of CNTs that provide a large specific surface area and excellent electrical conductivity, Co,N co-doped carbon nanocages that offer high electrocatalytic activity and hollow nanocage structures that ensure rapid diffusion kinetics. The conductive PEDOT-MIP provided specific binding sites for CBZ detection and significantly amplified the detection signal. The sensor showed superior selectivity for CBZ with an extremely low detection limit of 1.67 pmol L-1. Moreover, the method was successfully applied to detect CBZ in tomato, orange and apple samples, achieving satisfactory recovery and accuracy, thus demonstrating its practical feasibility.


Assuntos
Benzimidazóis , Compostos Bicíclicos Heterocíclicos com Pontes , Carbamatos , Técnicas Eletroquímicas , Eletrodos , Contaminação de Alimentos , Nanotubos de Carbono , Polímeros , Compostos Bicíclicos Heterocíclicos com Pontes/química , Técnicas Eletroquímicas/instrumentação , Nanotubos de Carbono/química , Carbamatos/análise , Carbamatos/química , Polímeros/química , Contaminação de Alimentos/análise , Benzimidazóis/química , Benzimidazóis/análise , Polímeros Molecularmente Impressos/química , Limite de Detecção , Impressão Molecular , Malus/química , Solanum lycopersicum/química , Citrus sinensis/química
11.
Biosensors (Basel) ; 14(6)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38920608

RESUMO

Agricultural products are vitally important for sustaining life on earth and their production has notably grown over the years worldwide in general and in Brazil particularly. Elevating agricultural practices consequently leads to a proportionate increase in the usage of pesticides that are crucially important for enhanced crop yield and protection. These compounds have been employed excessively in alarming concentrations, causing the contamination of soil, water, and air. Additionally, they pose serious threats to human health. The current study introduces an innovative tool for producing appropriate materials coupled with an electrochemical sensor designed to measure carbendazim levels. The sensor is developed using a molecularly imprinted polymer (MIP) mounted on a glassy carbon electrode. This electrode is equipped with multi-walled carbon nanotubes (MWCNTs) for improved performance. The combined system demonstrates promising potential for accurately quantifying carbendazim. The morphological characteristics of the synthesized materials were investigated using field emission scanning electron microscopy (FESEM) and the Fourier-transform infrared (FTIR) technique. The analytical curve was drawn using the electrochemical method in the range of 2 to 20 ppm while for HPLC 2-12 ppm; the results are presented as the maximum adsorption capacity of the MIP (82.4%) when compared with NIP (41%) using the HPLC method. The analysis conducted using differential pulse voltammetry (DPV) yielded a limit of detection (LOD) of 1.0 ppm and a repeatability of 5.08% (n = 10). The results obtained from the analysis of selectivity demonstrated that the proposed electrochemical sensor is remarkably efficient for the quantitative assessment of carbendazim, even in the presence of another interferent. The sensor was successfully tested for river water samples for carbendazim detection, and recovery rates ranging from 94 to 101% were obtained for HPLC and 94 to 104% for the electrochemical method. The results obtained show that the proposed electrochemical technique is viable for the application and quantitative determination of carbendazim in any medium.


Assuntos
Benzimidazóis , Carbamatos , Técnicas Eletroquímicas , Nanotubos de Carbono , Praguicidas , Carbamatos/análise , Benzimidazóis/análise , Praguicidas/análise , Nanotubos de Carbono/química , Técnicas Biossensoriais , Eletrodos , Materiais Biomiméticos/química , Limite de Detecção
12.
Anal Methods ; 16(25): 4093-4103, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38855904

RESUMO

The performance of the QuEChERS method in this study, as indicated by a high percentage (>90%) of recovery observations falling within the range of 60-140% and a sample replicate deviation (% RSD) of <20%, for the routine analysis of isoprocarb and carbaryl pesticides, has been evaluated over a 14-month period for the export of Indonesian coffee. Following a seven-day observation of the stability of these pesticides in coffee extract, it was found that the added standard calibration solution remained stable and useable for seven days when stored at 4 °C and -20 °C. This validated method, with high sensitivity (a LOQ of 0.001 mg kg-1 for isoprocarb and carbaryl), has been employed to monitor residues in Indonesian coffee exports to comply with maximum residue limits (MRLs). The samples with higher contamination levels were predominantly from robusta coffee (57.76%), followed by arabica coffee (6.17%). The detection rates for residues decreased by more than 90% in the last two months of the method's application. In the observation of coffee processing, it was found that isoprocarb residues in contaminated samples could be transferred to the processed coffee (roasted and its infusion) to a limited extent, while residues from the carcinogenic carbaryl were not detected due to evaporation. Additionally, chronic dietary risk assessment showed that contaminated samples of robusta and arabica coffees should not be considered a significant public health concern (hazard index HI < 1). However, continuous monitoring of pesticide residues in Indonesian coffee is still recommended, not only to conform to the MRLs of importing countries but also to ensure food trade.


Assuntos
Carbaril , Café , Resíduos de Praguicidas , Espectrometria de Massas em Tandem , Café/química , Resíduos de Praguicidas/análise , Indonésia , Carbaril/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Contaminação de Alimentos/análise , Limite de Detecção , Carbamatos/análise
13.
Sci Rep ; 14(1): 13064, 2024 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844596

RESUMO

This study aimed to investigate carbamate pesticide residues in different varieties of date palm fruits in the UAE, utilizing UHPLC-MS/MS. For sample preparation and clean-up, the efficiency and performance of different QuEChERS dispersive solid-phase extraction kits were compared. Precision and recovery were assessed at 10 µg kg-1 for the three kits, revealing that Kit 2 demonstrated the best performance. The selected QuEChERS method was validated to detect 14 carbamate residues in 55 date samples. The method exhibited strong linearity with R2 > 0.999 and low LOD (0.01-0.005 µg kg-1) and LOQ (0.003-0.04 µg kg-1). Excellent accuracy (recovery: 88-106%) and precision (RSD: 1-11%) were observed, with negligible matrix effect (- 4.98-13.26%). All samples contained at least one carbamate residue. While most detected residues were below their MRLs, carbosulfan was found in 21 samples, propoxur in 2 samples, and carbofuran in 1 sample above their MRLs. The hazard index (HI) was calculated for carbosulfan, phenmedipham, carbaryl, propoxur, carbofuran, and methomyl to assess potential health risks for date consumers. All HI values were below the safety limit of 1.0, indicating that the consumption of dates does not pose a non-carcinogenic health risk for adults and children.


Assuntos
Carbamatos , Frutas , Resíduos de Praguicidas , Phoeniceae , Espectrometria de Massas em Tandem , Phoeniceae/química , Resíduos de Praguicidas/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Carbamatos/análise , Frutas/química , Humanos , Medição de Risco , Extração em Fase Sólida/métodos , Contaminação de Alimentos/análise
14.
Sci Rep ; 14(1): 10293, 2024 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704412

RESUMO

In this study, a sensitive and selective fluorescent chemosensor was developed for the determination of pirimicarb pesticide by adopting the surface molecular imprinting approach. The magnetic molecularly imprinted polymer (MIP) nanocomposite was prepared using pirimicarb as the template molecule, CuFe2O4 nanoparticles, and graphene quantum dots as a fluorophore (MIP-CuFe2O4/GQDs). It was then characterized using X-ray diffraction (XRD) technique, Fourier transforms infrared (FT-IR) spectroscopy, scanning electron microscope (SEM), and transmission electron microscopy (TEM). The response surface methodology (RSM) was also employed to optimize and estimate the effective parameters of pirimicarb adsorption by this polymer. According to the experimental results, the average particle size and imprinting factor (IF) of this polymer are 53.61 nm and 2.48, respectively. Moreover, this polymer has an excellent ability to adsorb pirimicarb with a removal percentage of 99.92 at pH = 7.54, initial pirimicarb concentration = 10.17 mg/L, polymer dosage = 840 mg/L, and contact time = 6.15 min. The detection of pirimicarb was performed by fluorescence spectroscopy at a concentration range of 0-50 mg/L, and a sensitivity of 15.808 a.u/mg and a limit of detection of 1.79 mg/L were obtained. Real samples with RSD less than 2 were measured using this chemosensor. Besides, the proposed chemosensor demonstrated remarkable selectivity by checking some other insecticides with similar and different molecular structures to pirimicarb, such as diazinon, deltamethrin, and chlorpyrifos.


Assuntos
Praguicidas , Pirimidinas , Praguicidas/análise , Carbamatos/análise , Carbamatos/química , Pontos Quânticos/química , Polímeros Molecularmente Impressos/química , Polímeros/química , Espectrometria de Fluorescência/métodos , Grafite/química , Impressão Molecular/métodos , Adsorção , Limite de Detecção , Espectroscopia de Infravermelho com Transformada de Fourier , Nanocompostos/química , Nanocompostos/ultraestrutura
15.
Mikrochim Acta ; 191(6): 348, 2024 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-38805077

RESUMO

A novel aptamer-based sensor was developed using the signal amplification strategy of ring-opening metathesis polymerization (ROMP) and polyethyleneimine modified graphene oxide to achieve trace detection of carbendazim (CBZ). The dual identification of aptamer and antibody was used to avoid false positive results and improve the selectivity. Polyethyleneimine modified graphene oxide (GO-PEI), as a substrate material with excellent conductivity, was modified on the surface of a glassy carbon electrode (GCE) to increase the grafting amount of aptamer on the electrode surface. Moreover, a large number of cyclopentenyl ferrocene (CFc) was aggregated to form long polymer chains through ring-opening metathesis polymerization (ROMP), so as to significantly improve the detection sensitivity of the biosensor. The linear range of this sensor was 1 pg/mL-100 ng/mL with a detection limit as low as 7.80 fg/mL. The sensor exhibited excellent reproducibility and stability, and also achieved satisfactory results in actual sample detection. The design principle of such a sensor could provide innovative ideas for sensors in the detection of other types of targets.


Assuntos
Aptâmeros de Nucleotídeos , Benzimidazóis , Técnicas Biossensoriais , Carbamatos , Técnicas Eletroquímicas , Grafite , Limite de Detecção , Polietilenoimina , Polimerização , Grafite/química , Carbamatos/química , Carbamatos/análise , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Polietilenoimina/química , Técnicas Biossensoriais/métodos , Benzimidazóis/química , Aptâmeros de Nucleotídeos/química , Eletrodos , Reprodutibilidade dos Testes
16.
Food Chem ; 450: 139260, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38626714

RESUMO

High fluorescence intensity microspheres such as aggregation-induced emission fluorescence microspheres (AIEFM) have improved the sensitivity of lateral flow immunoassay (LFIA). The preparation of immune probes in LFIA usually adopts the chemical coupling strategy with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide for antibody coupling, which has the problems of low coupling efficiency, tedious coupling process, and poor repeatability. A biocompatible metal-phenolic network (MPN), which contains large amounts of phenols and galloyl groups, could easily, quickly, and stably couple with antibodies. Herein, we proposed a strategy based on MPN modification on ultrabright AIEFM surface as a novel label for the rapid detection of carbendazim. The limit of detection of AIEFM@MPN-LFIA was 0.019 ng/mL, which was 4.9 times lower than that of AIEFM-LFIA. In spiked samples, the average recoveries of AIEFM@MPN-LFIA ranged from 80% to 118% (coefficient of variation <13.45%). Therefore, AIEFM@MPN was a promising signal label that could improve the detection performance of LFIA.


Assuntos
Benzimidazóis , Carbamatos , Microesferas , Imunoensaio/métodos , Imunoensaio/instrumentação , Benzimidazóis/química , Benzimidazóis/análise , Carbamatos/análise , Carbamatos/química , Fenóis/análise , Fenóis/química , Limite de Detecção , Contaminação de Alimentos/análise , Fluorescência , Metais/química , Corantes Fluorescentes/química , Materiais Biocompatíveis/química
17.
Chemosphere ; 357: 142075, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38648985

RESUMO

Pesticides are considered one of the main sources of contamination of surface waters, especially in rural areas highly influenced by traditional agricultural practices. The objective of this work was to evaluate the impact caused by pesticides and their transformation products (TPs) related to olive groves in surface waters with strong agricultural pressure. 11 streams were monitored during four sampling campaigns over 2 years. A solid-phase extraction, followed by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) analysis was used in the quantitative target approach, with more than 70 validated compounds. Target method was combined with a suspect screening strategy involving more than 500 pesticides and TPs, using ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS) to identify additional pesticides and TPs out of the scope of analysis. A total of 43 different compounds were detected with the target method. The herbicide MCPA was present in all samples and at the highest concentration (1260 ng L-1), followed by the fungicide carbendazim (1110 ng L-1), and the herbicide chlorotoluron (706 ng L-1). The suspect screening strategy revealed the presence of 7 compounds out of the target analysis (1 pesticide and 6 TPs). 6 analytes were confirmed with the analytical standards. Semi-quantification results revealed that TPs exhibited higher concentrations than their corresponding parent compounds, indicating higher persistency. Some small streams showed a comparable number of pesticides and concentrations to the most polluted large river. The determined pesticide and TPs concentrations represented an estimated environmental hazard in almost all sampling sites under study. This work underscores the importance of including pesticide TPs and small streams impacted by extensive agricultural activities in water quality monitoring programs.


Assuntos
Agricultura , Monitoramento Ambiental , Olea , Praguicidas , Rios , Espectrometria de Massas em Tandem , Poluentes Químicos da Água , Rios/química , Poluentes Químicos da Água/análise , Praguicidas/análise , Medição de Risco , Olea/química , Extração em Fase Sólida , Carbamatos/análise , Cromatografia Líquida de Alta Pressão , Herbicidas/análise , Benzimidazóis/análise , Compostos de Fenilureia
18.
Environ Sci Pollut Res Int ; 31(19): 27749-27769, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38517634

RESUMO

Currently, pesticide production and use are on the rise globally. This trend is certain to continue in the coming decades with residues posing risks to the environment and human health even at low levels. Although various aspects of pesticides and their possible implications have widely been studied, such studies have mostly been carried out in developed countries leaving the rest of the world with little scientific information. We present here the results of a study on the occurrences, concentrations, and ecological risks of 30 pesticide residues (PRs) in water and sediment samples from a tropical freshwater Lake Hawassa in the Ethiopian Rift Valley. A total of 54 composite samples of water and sediment were collected from three sampling sites on three occasions. The samples were prepared by quick, easy, cheap, effective, rugged, and safe (QuEChERS) technique, and analyzed using GC-MS at Bless Agri Food Laboratory Service located in Addis Ababa, Ethiopia. The study applied the risk quotient (RQ) method to scrutinize the risks posed to aquatic biota by the detected PRs. The results showed occurrences of 18 and 20 PRs in the water and sediment samples, respectively. The majority, 78 and 75% of the detected PRs in water and sediment samples, respectively represent the organochlorine chemical class. Concentrations of heptachlor epoxide were significantly (p ≤ 0.001) higher than those of the remaining pesticides in both matrices. Of the pesticides detected, 77% were present in water and 83% in sediment samples and pose a serious risk (RQ ≥ 1) to the Lake Hawassa biota. This calls for further research to investigate the risks to human health posed by the PRs. The findings of this study can contribute to the development of global protocols, as they support the concerns raised about the ecological and public health impacts of PRs on a global level.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Clorados , Lagos , Resíduos de Praguicidas , Poluentes Químicos da Água , Lagos/química , Etiópia , Resíduos de Praguicidas/análise , Poluentes Químicos da Água/análise , Hidrocarbonetos Clorados/análise , Carbamatos/análise , Compostos Organofosforados/análise , Medição de Risco , Praguicidas/análise
19.
J Dairy Sci ; 107(4): 1916-1927, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37923201

RESUMO

This study aimed to use ultra-high-performance liquid chromatography coupled to a triple-quadrupole mass spectrometer to detect 11 carbamate pesticide residues in raw and pasteurized camel milk samples collected from the United Arab Emirates. A method was developed and validated by evaluating limits of detection, limits of quantitation, linearity, extraction recovery, repeatability, intermediate precision, and matrix effect. Due to the high protein and fat content in camel milk, a sample preparation step was necessary to avoid potential interference during analysis. For this purpose, 5 different liquid-liquid extraction techniques were evaluated to determine their efficiency in extracting carbamate pesticides from camel milk. The established method demonstrated high accuracy and precision. The matrix effect for all carbamate pesticides was observed to fall within the soft range, indicating its negligible effect. Remarkably, detection limits for all carbamates were as low as 0.01 µg/kg. Additionally, the coefficients of determination were >0.998, demonstrating excellent linearity. A total of 17 camel milk samples were analyzed, and only one sample was found to be free from any carbamate residues. The remaining 16 samples contained at least one carbamate residue, yet all detected concentrations were below the recommended maximum residue limits set by Codex Alimentarius and the European Union pesticide databases. Nonetheless, it is worth noting that the detected levels of ethiofencarb in 3 samples were close to the borderline of the maximum residue limit. To assess the health risk for consumers of camel milk, the hazard index values of carbofuran, carbaryl, and propoxur were calculated. The hazard index values for these 3 carbamate pesticides were all below 1, indicating that camel milk consumers are not at risk from these residues.


Assuntos
Resíduos de Praguicidas , Animais , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massas em Tandem/veterinária , Camelus , Leite/química , Cromatografia Líquida/métodos , Cromatografia Líquida/veterinária , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida de Alta Pressão/veterinária , Carbamatos/análise , Medição de Risco
20.
Anal Methods ; 15(37): 4811-4826, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37721714

RESUMO

Carbendazim is a broad-spectrum systemic fungicide that is used to control various fungal diseases in agriculture, horticulture, and forestry. Carbendazim is also used in post-harvest applications to prevent fungal growth on fruits and vegetables during storage and transportation. Carbendazim is regulated in many countries and banned in others, thus, there is a need for the sensing of carbendazim to ensure that high levels are avoided which can result in potential health risks. One approach is the use of electroanalytical sensors which present a rapid, but highly selective and sensitive output, whilst being economical and providing portable sensing platforms to support on-site analysis. In this minireview, we report on the electroanalytical sensing of carbendazim overviewing recent advances, helping to elucidate the electrochemical mechanism and provide conclusions and future perspectives of this field.


Assuntos
Benzimidazóis , Carbamatos , Benzimidazóis/análise , Carbamatos/análise , Verduras , Frutas/química
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