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1.
Adv Mater ; : e2108327, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35015320

RESUMO

xxxx. This article is protected by copyright. All rights reserved.

2.
Artigo em Inglês | MEDLINE | ID: mdl-35042337

RESUMO

Carbonaceous materials featuring both ordered graphitic structure and disordered defects hold great promise for high-performance K-ion batteries (KIBs) due to the concurrent advantages of high electronic conductivity, fast and reversible K+ intercalation/deintercalation, and abundant active K+ storage sites. However, it has been a lingering problem and remains a big challenge because graphitization and defects are intrinsic trade-off properties of carbonaceous materials. Herein, for the first time, we propose a cobalt-catalyzed carbonization strategy to fabricate porous carbon nanofibers that incorporate disordered defects in graphitic domain layers (PCNFs-DG) for fast and durable K+ storage. The Co catalyst not only ensures the formation of highly graphitized carbon shells around the Co particles but also introduces nanopores and doping defects in the following catalyst removal process. This idea of architecting defected-ordered graphitic carbon engineering guarantees fast reaction kinetics as well as structural stability with negligible interlayer expansion/contraction owing to the uncompromised electronic conductivity, expanded interlayer spacing, and regulated K+ storage mechanism. These appealing features translate to a high reversible capacity of 318.5 mAh g-1 at 100 mA g-1 and ultrahigh stability with almost 100% capacity retention over 2000 cycles in KIBs. This work puts in perspective that defected and ordered carbonaceous materials could be simultaneously achieved, advancing their performance for next-generation energy storage systems.

3.
Environ Pollut ; 292(Pt A): 118283, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34619177

RESUMO

A passive sampler in the soil environment is a relatively novel technique and has had quite limited applications, especially for pesticides. Oleic acid-embedded cellulose acetate membranes (OECAMs) were developed to evaluate the bioavailability of epoxiconazole (EPO) to earthworms (Eisenia fetida). The uptake of EPO by OECAMs (R2 = 0.975) and earthworms (R2 = 0.938) was compared and found to follow a two-compartment kinetic model. EPO sampling by OECAMs reached equilibrium (94%) within 2 d. OECAM could be used to determine the concentration of EPO in soil porewater. Furthermore, a significant linear relationship (R2 = 0.990) was observed between the EPO concentrations in earthworms and the OECAMs. The EPO concentrations in the porewater and OECAMs were lower in soils with a higher organic matter (OM) content. The EPO concentrations in the porewater, earthworms, and OECAMs decreased by 64.4, 49.0, and 56.1%, respectively, in the presence of 0.5% biochar, compared with the control. Furthermore, the use of OECAMs versus earthworms for soil testing also allows you to avoid factors that increase variance in organisms, such as avoidance behaviors or feeding. Therefore, OECAMs show good potential for use as a passive sampler to evaluate the bioavailability of EPO.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Disponibilidade Biológica , Celulose/análogos & derivados , Compostos de Epóxi , Ácido Oleico , Solo , Poluentes do Solo/análise , Triazóis
4.
J Hazard Mater ; 422: 126787, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34399219

RESUMO

Epoxiconazole is an effective pesticide to control Fusarium head blight (FHB), and the application will increase. To investigate the ecotoxicity of epoxiconazole to soil microbiome, we carried out an indoor experiment in which soils from two main regions of wheat production in China (Nanjing and Anyang) were treated with epoxiconazole (0, 0.0625, 0.625, or 6.25 mg kg-1) and incubated for 90 days. Under epoxiconazole stress, for bacteria and fungi, the abundance was increased and the diversity and community were impacted. In Anyang soil, the half-life of epoxiconazole was short with more increased species (linear discriminant analysis effect size biomarkers) and more increased xenobiotics biodegradation pathways in epoxiconazole treatments. The increased species mostly due to high abundance in initial state and more positive connections of the species. Co-occurrences revealed that epoxiconazole tightened bacterial connection, and increased positive correlations in Anyang soil. The N transformation was influenced with increased nifH and amoA; and the contents of NH4+-N and NO3--N were also increased. The functions of C, S, and manganese metabolisms were also impacted by epoxiconazole. This work expands our understanding about epoxiconazole degradation and help us to properly assess the risk of epoxiconazole in soil.


Assuntos
Solo , Triazóis , Biodegradação Ambiental , Compostos de Epóxi/toxicidade , Triazóis/análise , Triazóis/toxicidade
5.
Sci Total Environ ; 803: 149929, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34478900

RESUMO

Nitrous acid (HONO) is a major source of hydroxyl radicals in the troposphere through its photolysis, and can significantly influence ozone (O3) levels, thereby causing considerable crop yield losses. Previous studies have assessed relative crop yield losses by using exposure-response equations with observed or simulated O3, however, the contribution of enhanced O3 due to potential HONO sources to the crop yield losses has never been quantified. In this study, for the first time, we evaluated the crop yield losses caused by potential HONO sources in the North China Plain (NCP), which is one of the major grain-producing areas in China suffering from heavy O3 pollution, by using the Weather Research and Forecasting/Chemistry (WRF-Chem) model during the wheat and maize growing seasons of 2016. HONO simulations were significantly improved after including six potential HONO sources in the WRF-Chem model. The potential HONO sources produced a daily maximum 8-h O3 enhancement of 8.1/8.2 ppb during the wheat/maize growing seasons, respectively, and led to ~11.4%/3.3% relative yield losses for wheat/maize, respectively, corresponding to approximately US$3.78/0.66 billion losses, respectively, in NCP in 2016. The above results suggest that potential HONO sources play a significant role in O3 formation and could induce high crop yield losses globally.


Assuntos
Poluentes Atmosféricos , Ozônio , Poluentes Atmosféricos/análise , China , Ácido Nitroso , Ozônio/análise , Estações do Ano
6.
Sci Total Environ ; 806(Pt 1): 150247, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34562762

RESUMO

Observations of volatile organic compounds (VOCs) are a prerequisite for evaluating the effectiveness of government efforts targeting VOC pollution. Here, based on the one-year online VOC measurement in 2018 in Beijing, systematic analyses and model simulation were conducted to illuminate VOC characteristics, emission sources, regional hotspots and behaviours in response to O3 formation. The observed mean VOC concentration in 2018 was 29.12 ± 17.64 ppbv declined distinctly compared to that in 2015 and 2016. Vehicle exhaust (39.95%), natural gas/liquefied petroleum gas (22.04%) and industrial sources (20.64%) were the main contributors to VOCs in Beijing. Regional transport, mainly from the south-south-east (SSE) and south-south-west (SSW), quantitatively contributed 36.65%-55.06% to VOCs based on our developed method. O3 sensitivity tended to be in the transition regime in summer identified by ground-based and satellite observations. Strong solar radiation along with high temperature and low humidity aggravated O3 pollution that was further intensified by regional transport from southern polluted regions. The model simulation determined that turning off CH3CHO related reactions brought about the most predominantly short-term and long-run O3 reduction, indicating that control policies in VOC species should be tailored, instead of one-size-fits-all. Overall, region-collaborated and active VOC-species-focused strategies on VOC controls are imperative.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Pequim , China , Monitoramento Ambiental , Ozônio/análise , Compostos Orgânicos Voláteis/análise
7.
J Hazard Mater ; 424(Pt A): 127223, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34600378

RESUMO

Pyrisoxazole, an isoxazoline-class fungicide, has been registered and used for approximately 19 years. However, its environmental transformation products (TPs) and corresponding ecotoxicological effects remain ambiguous. In this study, the photolysis, hydrolysis, and soil transformation behavior of pyrisoxazole were systematically investigated by indoor simulation experiments and analyzed by liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) and UNIFI software. Transformation products in different environemnts were effectively identfied by a proposed workflow, which organically combined suspect and non-target screening strategies. In total, 17 TPs were screened out. Eight TPs were confirmed using the corresponding reference standards. Structures of another 9 compounds were tentatively proposed based on diagnostic evidence. Among them, 14 products were reported for the first time. The transformation pathways of pyrisoxazole in soil and water were proposed. Pathway analysis demonstrated that the different pH of aqueous solutions had little effect on the pathways, while the influence of different soil types and oxygen conditions was evident. Finally, the toxicity of the proposed TPs to fish and daphnids was predicted using ECOSAR software. These proposed TPs in soil and water, transformation pathways, and predicted ecotoxicity information could provide systematic insight into the fate and environmental risks of pyrisoxazole.


Assuntos
Solo , Poluentes Químicos da Água , Animais , Cromatografia Líquida , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Fluxo de Trabalho
8.
Nanomaterials (Basel) ; 11(12)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34947802

RESUMO

Silicon (Si) is expected to be a high-energy anode for the next generation of lithium-ion batteries (LIBs). However, the large volume change along with the severe capacity degradation during the cycling process is still a barrier for its practical application. Herein, we successfully construct flexible silicon/carbon nanofibers with a core-shell structure via a facile coaxial electrospinning technique. The resultant Si@C nanofibers (Si@C NFs) are composed of a hard carbon shell and the Si-embedded amorphous carbon core framework demonstrates an initial reversible capacity of 1162.8 mAh g-1 at 0.1 A g-1 with a retained capacity of 762.0 mAh g-1 after 100 cycles. In addition, flexible LIBs assembled with Si@C NFs were hardly impacted under an extreme bending state, illustrating excellent electrochemical performance. The impressive performances are attributed to the high electric conductivity and structural stability of the porous carbon fibers with a hierarchical porous structure, indicating that the novel Si@C NFs fabricated using this electrospinning technique have great potential for advanced flexible energy storage.

9.
Food Chem ; 376: 131883, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34971887

RESUMO

A fast, effective, and environmental-friendly method was developed for enantioseparation and analysis of mefentrifluconazole in vegetables based on supercritical fluid chromatography tandem mass spectrometry. The enantioselective behaviors of mefentrifluconazole enantiomers in tomato, cucumber, and pepper in the greenhouse, and pickled cucumber and pepper during processing were investigated. Mefentrifluconazole enantiomers could obtain baseline separation within 2 min. The average recoveries of all matrices ranged from 78.4% to 119.0%, with relative standard deviations less than 16.8% for two enantiomers. S-(+)-mefentrifluconazole was preferentially degraded in pepper, while there was no enantioselectivity in tomato and cucumber under field conditions. During processing, S-(+)-mefentrifluconazole was reduced preferentially than R-(-)-mefentrifluconazole in pickled cucumber and cucumber brine. Inversely, R-(-)-mefentrifluconazole degraded faster than S-(+)-mefentrifluconazole in pepper brine. But, no obvious enantioselectivity was observed in pickled pepper. The result of this study could contribute to a more accurate dietary risk assessment of mefentrifluconazole in vegetables and processed products.

10.
Adv Mater ; : e2106885, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34798686

RESUMO

Improving the enrichment of drugs or theranostic agents within tumors is vital to achieve effective cancer diagnosis and therapy with reduced dosage and damage to normal tissues. In this work, we describe an enzyme-mediated AIEgen intracellular polymerization strategy that can simultaneously promote the accumulation and retention of the AIEgen in the tumor for prolonged imaging and enhanced tumor growth inhibition. We rationally designed an AIEgen-peptide conjugate (D2P1) and cyanobenzothiazole-cysteine (3CBT) that can undergo rapid condensation reaction to form nanoaggregates in tumor cells. Upon tumor-specific cathepsin protease reaction, the cleavage of peptides induces condensate polymerization between the exposed cysteine and 2-cyanobenzothiazole on 3CBT, triggering accumulation of D2P1 into the tumor site, leading to fluorescence light-up. Such enzyme-mediated polymerization of D2P1 and 3CBT alters cellular motility via disrupting actin organization and in turn inhibiting cell proliferation. In addition, due to the built-in intrinsic photosensitization property of the AIEgen, the accumulation of D2P1 could remarkably promote the tumor photodynamic therapy effect in vivo under light irradiation. This study thus represents the enzyme-mediated intracellular polymerization system with high potential to improve the diagnostic and therapeutic outcomes of tumors in vivo. This article is protected by copyright. All rights reserved.

11.
Mater Horiz ; 8(5): 1454-1460, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34846453

RESUMO

A living therapeutic system based on attenuated Salmonella was developed via metabolic engineering using an aggregation-induced emission (AIE) photosensitizer MA. The engineered bacteria could localize in the tumor tissues and continue to colonize and express exogenous genes. Under light irradiation, the encoded VEGFR2 gene was released and expressed in tumor tissues, which can suppress angiogenesis induced by a T cell-mediated autoimmune response and inhibit tumor growth.

12.
Nucleic Acids Res ; 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34747471

RESUMO

The structural variability data of drug transporter (DT) are key for research on precision medicine and rational drug use. However, these valuable data are not sufficiently covered by the available databases. In this study, a major update of VARIDT (a database previously constructed to provide DTs' variability data) was thus described. First, the experimentally resolved structures of all DTs reported in the original VARIDT were discovered from PubMed and Protein Data Bank. Second, the structural variability data of each DT were collected by literature review, which included: (a) mutation-induced spatial variations in folded state, (b) difference among DT structures of human and model organisms, (c) outward/inward-facing DT conformations and (d) xenobiotics-driven alterations in the 3D complexes. Third, for those DTs without experimentally resolved structural variabilities, homology modeling was further applied as well-established protocol to enrich such valuable data. As a result, 145 mutation-induced spatial variations of 42 DTs, 1622 inter-species structures originating from 292 DTs, 118 outward/inward-facing conformations belonging to 59 DTs, and 822 xenobiotics-regulated structures in complex with 57 DTs were updated to VARIDT (https://idrblab.org/varidt/ and http://varidt.idrblab.net/). All in all, the newly collected structural variabilities will be indispensable for explaining drug sensitivity/selectivity, bridging preclinical research with clinical trial, revealing the mechanism underlying drug-drug interaction, and so on.

13.
Angew Chem Int Ed Engl ; 60(50): 26218-26225, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34549498

RESUMO

We propose an in situ template method to directionally induce the construction of germanium phosphide nanobar (GeP-nb) corals with an adjustable aspect ratio. The GeP nanobars grown onto conductive matrix with high aspect ratio expose more quickest electron-ion transportation facets for fast reaction dynamics. The customized GeP-nb electrode delivers a self-healable homeostatic behavior by reversibly stabilizing GeP crystalline structure through multi-phase reactions to maintain structural integrity and cycling stability (850 mAh g-1 at 1 A g-1 after 500 cycles). As a result, the GeP-nb presents the highest Li+ diffusion coefficient (6.21×10-11  cm2 s-1 ) among all the Ge-based anode materials studied so far, rendering an excellent rate performance (620 mAh g-1 at 5 A g-1 ) as a lithium-ion battery (LIB) anode.

14.
Sci Total Environ ; 795: 148777, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34229239

RESUMO

The combination effects of triazole fungicides on aquatic organisms remain largely unknown. In current study, an integrated histological, transcriptome, metabonomics and microbiology was applied to investigate the mixture effects and risk of tebuconazole (TEB) and difenoconazole (DIF) co-exposure on zebrafish liver and gonad at aquatic life benchmark. TEB and DIF mixture showed additive effect on the acute toxicity to adult zebrafish, the combined toxicity on liver was less than the additive effect of individual TEB and DIF, and TEB and DIF mixture also reduced the toxic effects on gonad and intestinal microflora. Transcriptomics and metabolomics further showed TEB and DIF mixture could induce more differentially expressed genes (DEGs) to regulate the metabolic pathways involved in energy metabolism, steroid hormone biosynthesis, retinol metabolism and microbial metabolism, to balance the energy metabolism and supplies, and maintain the steroid hormone and RA level, further reduced the toxic effect on liver and gonad caused by TEB and DIF. Our results showed the different responses and patterns on transcriptional and metabolic profiles mediated in the diverse toxicity and combination effects of TEB and DIF. The present results provided a deep mechanistic understanding of the combined effects and mode of action of DIF and TEB mixture on aquatic organisms, suggesting the concept of additive effects might sufficiently protective when evaluated the combination effects and ecological risk of TEB and DIF at aquatic life benchmarks.


Assuntos
Dioxolanos , Fungicidas Industriais , Animais , Fungicidas Industriais/toxicidade , Triazóis/toxicidade , Peixe-Zebra
15.
Talanta ; 233: 122587, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215077

RESUMO

Phosphopeptides were of great significance in disease diagnosis and monitoring its dynamic changes. In this article, we proposed a more efficient method to synthesize a kind of bimetallic mesoporous silica nanomaterials (Fe3O4@mSiO2-PO3-Ti4+/Zr4+) and applied it to the analysis of phosphopeptides in human saliva samples based on IMAC technology. The chelation group was introduced into mesopores at the same time as the formation of mesoporous silica which significantly reduced the synthesis procedure and improved the synthesis efficiency. The as-prepared materials showed great sensitivity, selectivity and size-exclusion performance for phosphopeptides in standard ß-casein digests. More importantly, the materials identified 85 phosphopeptides in disease saliva samples which provided a candidate choice in future clinical examination.


Assuntos
Fosfopeptídeos , Saliva , Humanos , Íons , Dióxido de Silício , Titânio
16.
J Agric Food Chem ; 69(30): 8530-8535, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34313440

RESUMO

In this study, the stereoselective bioactivity, acute toxicity, and environmental fate for famoxadone enantiomers were reported for the first time. Five representative pathogens (e.g., Alternaria solani) were used to investigate enantioselective activity, and three non-target organisms (e.g., Selenastrum bibraianum) were used to evaluate acute toxicity. S-Famoxadone was 3.00-6.59 times more effective than R-famoxadone. R-Famoxadone also showed 1.80-6.40 times more toxicity than S-famoxadone toward S. bibraianum and Daphnia magna. The toxicity of R-famoxadone was 100 times more toxic than S-famoxadone toward Danio rerio. Under aerobic conditions, the half-life (t1/2) for famoxadone enantiomer degradation was 46.2-126 days in different soils and the enantiomeric fraction (EF) ranged from 0.435 to 0.470 after 120 days. R-Famoxadone preferentially degraded in three soils, resulting in an enrichment of S-famoxadone. Under anaerobic conditions, t1/2 of famoxadone enantiomers was 62.4-147 days in different soils and the EF ranged from 0.489 to 0.495, indicating that famoxadone enantiomers were not enantioselective. This study will be useful for the environmental and health risk assessments for famoxadone enantiomers.


Assuntos
Fungicidas Industriais , Alternaria , Fungicidas Industriais/toxicidade , Solo , Estereoisomerismo , Estrobilurinas
17.
J Hazard Mater ; 418: 126303, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34329017

RESUMO

Difenoconazole is a widely used triazole fungicide that has been frequently detected in the environment, but comprehensive study about its environmental fate and toxicity of potential transformation products (TPs) is still lacking. Here, laboratory experiments were conducted to investigate the degradation kinetics, pathways, and toxicity of transformation products of difenoconazole. 12, 4 and 4 TPs generated by photolysis, hydrolysis and soil degradation were identified via UHPLC-QTOF/MS and the UNIFI software. Four intermediates TP295, TP295A, TP354A and TP387A reported for the first time were confirmed by purchase or synthesis of their standards, and they were further quantified using UHPLC-MS/MS in all tested samples. The main transformation reactions observed for difenoconazole were oxidation, dechlorination and hydroxylation in the environment. ECOSAR prediction and laboratory tests showed that the acute toxicities of four novel TPs on Brachydanio rerio, Daphnia magna and Selenastrum capricornutum are substantially lower than that of difenoconazole, while all the TPs except for TP277C were predicted chronically very toxic to fish, which may pose a potential threat to aquatic ecosystems. The results are important for elucidating the environmental fate of difenoconazole and assessing the environmental risks, and further provide guidance for scientific and reasonable use.


Assuntos
Solo , Poluentes Químicos da Água , Animais , Dioxolanos , Ecossistema , Cinética , Fotólise , Espectrometria de Massas em Tandem , Triazóis/toxicidade , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
18.
Ecotoxicol Environ Saf ; 220: 112388, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34091183

RESUMO

Given the key role of bees as indicators for environmental assessment, residues in bees and bee products have attracted great interest. In this regard, an improved, highly sensitive method for quantifying the insecticide pyriproxyfen and its four metabolites (4'-OH-Pyr, DPH-Pyr, 2-OH-PY, 4'-OH-POP) in honeybees, larvae, and bee products (honey, pollen, royal jelly and wax) should be established. For this purpose, we used ultra-performance liquid chromatography coupled with triple-quadrupole mass spectrometry for rapid quantification (≤5 min). Recoveries for various matrices ranged from 73.77% to 114.97%, with satisfactory intra-day and inter-day precision (relative standard deviations of 0.03-8.61% and 0.10-7.25%, respectively). The results demonstrated excellent linearity (R2 > 0.9903) with a limit of quantification of 1 µg/kg for six different matrices. We collected and analyzed 597 samples (honey, bees and wax) from four major beekeeping areas in China. Only 47 of these samples contained residues of pyriproxyfen and two of its metabolites (2-OH-PY, 4'-OH-Pyr), and high levels of contamination were found in bee samples (2-739 µg/kg), with substantive accumulation in wax (levels were 9.49% higher than in other samples). The result demonstrate that the method provides a reliable and convenient means of monitoring pyriproxyfen and its metabolites in bee products for better product quality, human health, and international commercial competition and also lays a foundation for risk assessment of potential pyriproxyfen contamination in China.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Mel/análise , Resíduos de Praguicidas/química , Piridinas/química , Espectrometria de Massas em Tandem/métodos , Animais , Abelhas , China , Cromatografia Líquida/métodos , Ácidos Graxos/química , Inseticidas/química , Pólen/química
19.
Front Pharmacol ; 12: 647591, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34122069

RESUMO

According to the classical pharmacophore fusion strategy, a series of 6-arylureido-4-anilinoquinazoline derivatives ( Compounds 7a - t ) were designed, synthesized, and biologically evaluated by the standard CCK-8 method and enzyme inhibition assay. Among the title compounds, Compounds 7a , 7c , 7d , 7f , 7i , 7o , 7p , and 7q exhibited promising anti-proliferative bioactivities, especially Compound 7i , which had excellent antitumor activity against the A549, HT-29, and MCF-7 cell lines (IC50 = 2.25, 1.72, and 2.81 µM, respectively) compared with gefitinib, erlotinib, and sorafenib. In addition, the enzyme activity inhibition assay indicated that the synthesized compounds had sub-micromolar inhibitory levels (IC50, 11.66-867.1 nM), which was consistent with the results of the tumor cell line growth inhibition tests. By comparing the binding mechanisms of Compound 7i (17.32 nM), gefitinib (25.42 nM), and erlotinib (33.25 nM) to the EGFR, it was found that Compound 7i could extend into the effective region with a similar action conformation to that of gefitinib and interact with residues L85, D86, and R127, increasing the binding affinity of Compound 7i to the EGFR. Based on the molecular hybridization strategy, 14 compounds with EGFR inhibitory activity were designed and synthesized, and the action mechanism was explored through computational approaches, providing valuable clues for the research of antitumor agents based on EGFR inhibitors.

20.
J Agric Food Chem ; 69(25): 7199-7208, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34142545

RESUMO

A robust isotope-labeled internal standard method was established for the detection of 22 pesticides and metabolite residues in four kinds of fish; two were from freshwater fish, and two were from marine fish. Pesticides with wide application possibilities in rice in China, strong leaching to water, or high bioconcentration factors (BCF) in fish were selected. The samples were extracted with 1% acetic acid-99% acetonitrile. The extracts were first purified by solid-phase extraction (PEP-plus), cleaned with dispersive-solid-phase extraction (PSA and C18), and finally analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The results showed that good linearities for the target compounds were observed in the range of 0.1-100 ng/mL, and the correlation coefficient (R2) of each compound was greater than 0.99. The recoveries of the method were within 70-120% with RSDs <20% at three different spiked concentration levels (0.5, 5, and 100 ng/g). The quantitative limit of the method was 0.5-5 ng/g. The method is shown to be sensitive and accurate and can meet the demands for the quantitative analysis of pesticides in fish.


Assuntos
Resíduos de Praguicidas , Praguicidas , Animais , China , Cromatografia Líquida , Resíduos de Praguicidas/análise , Extração em Fase Sólida , Espectrometria de Massas em Tandem
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